VOLUME FIFTEEN NUMBER SIX

 

 

December 2020

Greetings AASPT Members and IJSPT Subscribers:
 
The IJSPT editorial staff would like to announce that the December issue of The International Journal of Sports Physical Therapy is available. We are pleased to provide you with 37 international articles in various categories to assist in your quest for evidence-based information that will promote excellence in your clinial practice.  
 
This month is bittersweet as we part ways with the AASPT under whose auspices we have been publishing for 15 years. We now pledge to continue to work toward our mission of providing practicing sports physical therapists and rehabilitation professionals with high-quality, relevant, peer-reviewed research. We hope that each and every one of you will join us in the next chapter of our journey.  
 
Beginning in 2021, look for a new website (www.ijspt.org), enhanced features such as “on-line first” publication capability, new submission subsections to include international perspective commentary and technical notes where authors are able to share clinical pearls, as well as additional media content such as blogs, podcasts, and social media, to encourage the exchange of current, thought-provoking information.
 
The International Journal of Sports Physical Therapy will remain available to all AASPT and IFSPT members moving forward. If you have not already done so, please sign up here (https://nasmi.org/ijspt-sign-up-2021/ ) to receive access to the IJSPT first and stay up to date on all news related to the IJSPT.
 
We hope each and every one of you will sign up to continue to receiving the journal as we grow in 2021.
 
Sincerely,
 
Ashley Campbell
Barb Hoogenboom
Mike Voight
Mary Wilkinson

 

SYSTEMATIC REVIEW/META-ANALYSIS
Dual-Task Assessment Implications for Anterior Cruciate Ligament Injury: A Systematic Review.
Authors: Ness BM, Zimney K, Schweinle WE, Cleland JA

Several systematic reviews have evaluated the role of dual-task assessment in individuals with concussion. However, no systematic reviews to date have investigated dual-task protocols with implications for individuals with anterior cruciate ligament (ACL) injury or ACL reconstruction (ACLR). The purpose of this manuscript was to systematically review the evidence on dual-task assessment practices applicable to those with ACL deficiency/ACLR, specifically with the aim to identify motor-cognitive performance costs.  Ten studies were included for analysis, all of which were published within the prior ten years. Performance deficits were identified in those with either ACL deficiency or ACLR while dual-tasking, such as prioritization of postural control at the expense of cognitive performance, impaired postural control In single limb stance, greater number of cognitive errors, and increased step width coefficient of variation while walking. No studies examined those with prior ACL injury or ACLR during tasks that mimicked ACL injury mechanisms such as jump-landing or single-leg cutting. The results of the current systematic review suggests that postural control, gait, and/or cognitive deficits exist when evaluated under a dual-task paradigm in those with ACL deficiency or ACLR. This systematic review highlights the need for future research on dual-task assessment for individuals who have sustained an ACL injury or undergone ACLR, specifically utilizing more complex athletic movements.

Abstract  |  IJSPT-15_6-01-Ness

A Systematic Review and Meta-Analysis of Common Therapeutic Exercises That Generate Highest Muscle Activity in the Gluteus Medius and Gluteus Minimus Segments.
Authors: Moore D, Semciw AI, Pizzari T

The gluteus medius (GMed) and gluteus minimus (GMin) muscle segments demonstrate different responses to pathology and aging, hence it is important in rehabilitation that prescribed therapeutic exercises can effectively target the individual segments with adequate exercise intensity for strengthening. The purpose of this systematic review was to evaluate whether common therapeutic exercises generate at least high (> 40% maximum voluntary isometric contraction (MVIC)) electromyographic (EMG) activity in the GMed (anterior, middle and posterior) and GMin (anterior and posterior) segments. Seven databases (MEDLINE, EMBASE, CINAHL, AusSPORT, PEDro, SPORTdiscus and Cochrane Library) were searched from inception to May 2018 for terms relating to gluteal muscle, exercise, and EMG. The search yielded 6918 records with 56 suitable for inclusion. Quality assessment, data extraction and data analysis were then undertaken with exercise data pooled into a meta-analysis where two or more studies were available for an exercise and muscle segment. For the GMed, different variations of the hip hitch/ pelvic drop exercise generated at least high activity in all segments.  The dip test, and isometric standing hip abduction are other options to target the anterior GMed segment, while isometric standing hip abduction can be used for the posterior GMed segment. For the middle GMed segment, the single leg bridge; side-lying hip abduction with hip internal rotation; lateral step-up; standing hip abduction on stance or swing leg with added resistance; and resisted side-step were the best options for generating at least high activity. Standing isometric hip abduction and different variations of the hip hitch/ pelvic drop exercise generated at least high activity in all GMin segments, while side-lying hip abduction, the dip test, single leg bridge and single leg squat can also be used for targeting the posterior GMin segment. The findings from this review provide the clinician with confidence in exercise prescription for targeting individual GMed and GMin segments for potential strengthening following injury or aging.

Abstract  |  IJSPT-15_6-02-Moore

A Systematic Review of the Effects of Blood Flow Restriction Training on Quadriceps Muscle Atrophy and Circumference Post ACL Reconstruction.
Authors: Charles D, White R, Reyes C, Palmer D

ACL reconstruction often results in an extended period of muscle atrophy and weakness. Blood flow restriction (BFR) training is a technique that has been shown to decrease muscle atrophy in a variety of populations. The purpose of this systematic review was to analyze the research presented on the effect of blood flow restriction training on quadriceps muscle atrophy and circumference post ACL reconstruction. Articles were reviewed using the databases Google Scholar, PubMed, and EBSCO. Keywords included blood flow restriction training, ACL reconstruction, and quadriceps.  Four studies met the selection criteria and were assessed using the GRADE scale, which analyzes the strength of a study based on study limitations, precision, consistency, directness, and publication bias. After a GRADE designation was assigned, the following information was extracted from and compared across the studies: participant demographics, cuff used, graft used during ACL reconstruction, tool used to assess muscle atrophy, protocol used, and conclusions. Three out of the four included studies showed some amount of an increase in femoral muscle cross sectional area after the use of BFR combined with low-intensity resistance training (LIRT). The strength of all four studies was moderate when assessed using the GRADE scale. This review of the available evidence yields promising results regarding the use of BFR and LIRT in the remediation of femoral muscle atrophy after an ACL reconstruction. Further research is necessary before BFR can be recommended for use in clinical settings.

Abstract  |  IJSPT-15_6-03-Charles

ORIGINAL RESEARCH
Effect of Blood Flow Restriction Training On Muscular Performance, Pain and Vascular Function.
Authors:  Early KS, Rockhill M, Bryan A, Tyo B, Buuck D, McGinty J

Blood flow restriction (BFR) training enhances muscular strength and hypertrophy in several populations including older adults and injured athletes. However, the efficacy of emerging BFR technologies on muscular adaptations, vascular health, and pain is unclear. The purpose of this study was to examine muscular performance, pain and vascular function in response to eight weeks of BFR compared to traditional resistance training and a control group. Thirty-one overtly healthy participants underwent eight weeks of supervised high load resistance training (RES), low load resistance training with BFR (BFR) or no training (control, CON). RES and BFR (with pneumatic bands) performed seven upper and lower body exercises, two to three sessions per week at 60% and 30% of one-repetition maximum (1RM), respectively. Twenty-four hours post-exercise, general muscle soreness was assessed via a visual analog scale (VAS) and present pain intensity (PPI) of the McGill Pain Questionnaire. At baseline and after eight weeks, participants underwent one-repetition maximum (1RM), and flow-mediated dilation (FMD) testing. At baseline all groups exhibited similar muscle strength and endurance and vascular function. At the end of training, RES and BFR groups significantly increased muscle strength (1RM) to a similar magnitude as compared to the CON group (p<0.0001), but did not alter body composition. FMD significantly increased in RES and BFR groups compared to CON group (p=0.006). VAS and PPI were similar between RES and BFR groups throughout the exercise sessions until VAS decreased in the BFR group after the last session compared to the RES group (p=0.02). Compared to RES, BFR with resulted in similar muscular performance (strength and endurance) and vascular improvements at a lower exercise intensity, suggesting BFR is an effective alternative to high load resistance training. Further longitudinal studies may gain greater understanding general muscle pain and soreness pain of using BFR.

Abstract  |  IJSPT-15_6-04-Early

Effects of Blood Flow Restriction Training on Handgrip Strength and Muscular Volume of Young Women.
Authors: Fernandes DZ, Weber VMR, da Silva MPA, Stavinski NG, de Oliveira LEC, Tracz EHC, Ferreira SA, da Silva DF, Queiroga MR

High-intensity training methods are generally recommended to increase muscle mass and strength, with training loads of 60-70% 1RM for novice and 80-100% 1RM for advanced individuals. Blood flow restriction training, despite using lower intensities (30-50% 1RM), can provide similar improvements in muscle mass and strength. However, studies commonly investigate the effects of blood flow restriction training in large muscular groups, whereas there are few studies that investigated those effects in smaller muscle groups, such as the muscles involved in grasping (e.g, wrist flexors; finger flexors). Clinically, smaller muscular groups should also be considered in intervention programs, given that repetitive stress, such as repeated strain injuries, affects upper limbs and may lead to chronic pain and incapacity for work. The purpose of the present study was to examine the effects of blood flow restriction training in strength and anthropometric indicators of muscular volume in young women. Twenty-eight university students, 18 to 25 years of age, were randomly assigned into two groups, blood flow restriction training (BFR, n=14) and traditional training (TRAD, n=14). The anthropometric measures and maximum handgrip strength (MHGS) test were performed before and after the intervention. The participants did three weekly sessions of dynamic concentric contraction exercises on a dynamometer for four weeks (12 sessions). Each session had a time length of five minutes and the intensity was established from a percentage of MHGS at 30-35% in the first week, 40-45% in the second and 50-55% in third/fourth weeks. Three sets of 15-25 handgrip repetitions were performed until a failure with a 30 seconds rest for BFR training and three sets of 8-12 repetitions with one-minute rest for TRAD training. A significant increase was found in the arm muscle circumference (20.6±2.2 vs 21.6±1.7cm) and right MHGS (32.7± 4.5 vs 34.3±4.1 kgf) and left MHGS (28.0±5.5 vs 30.9±4.1 kgf) for the BFR training, and the left MHGS (27.6 ± 5.0 vs 31.0±6.1 kgf) for the TRAD training.  The authors concluded that dynamometer training with blood flow restriction, performed with low to moderate loads, was more effective than the traditional training in increasing HGS and muscle volume in young women.

Abstract  |  IJSPT-15_6-05-Fernandes

Validity and Reliability of Video-Based Analysis of Upper Trunk Rotation During Running.
Authors: Weber CF, McClinton S

Two-dimensional (2D) video analysis is a practical tool for assessing biomechanical factors that may contribute to running-related injury. Asymmetrical or altered coordination of transverse plane trunk movement has been associated with low back pain, increased vertical and horizontal ground reaction forces, and altered hip abduction torque and strength. However, the reliability and validity of 2D transverse plane upper trunk rotation (UTR) has not been assessed. The purpose of this study was to determine the validity and reliability of 2D video-based, transverse plane UTR measurement during running.  Sixteen runners ran at self-selected speed on a treadmill while three-dimensional (3D) and 2D motion capture occurred synchronously. Two raters measured peak UTR for five consecutive strides on two occasions. Interrater and intrarater reliability and the minimum detectable change was calculated for right and left peak 2D UTR measurement. Concurrent validity and agreement between 2D and 3D measures were determined by calculating Pearson Product Correlation Coefficients (r) and Bland-Altman plots, respectively. Using a single UTR measure per runner, intrarater and interrater reliability (ICC2,1) was excellent (intrarater ICC2,1 range: 0.989-0.999; interrater ICC2,1 range: 0.990-0.995) and the minimum detectable change was 0.39-1.4 degrees. Measurements in 2D and 3D were significantly correlated for peak UTR (all r ≥ 0.986; all p-values < 0.001) and showed good agreement in Bland-Altman plots.  The authors concluded that two-dimensional video-based measurement of transverse plane peak UTR is valid and reliable. Furthermore, UTR measurement may provide clinical insight into gait deviations in the transverse plane that alter angular momentum and increase risk for running-related injury.

Abstract  |  IJSPT-15_6-06-Weber

Effects of Surface on Triple Hop Distance and Kinematics.
Authors: Brewer AB, Nguyen AD, Taylor JB, Ford KR

The single leg triple hop (SLTH) test is often utilized by rehabilitation practitioners as a functional performance measure in a variety of patient groups. Accuracy and consistency are important when measuring the patient progress and recovery. Administering the SLTH test on different surfaces, consistent with the patient’s sport, may affect the hop distances and movement biomechanics. The purpose of this study was to examine the effects of court and turf surfaces on the hop distance, limb symmetry index (LSI), and lower extremity kinematics of a SLTH test.  Recreationally active female participants (n=11, height 163.8±7.1cm, mass 63.1±7.1kg, age 18.9±0.9yrs), without injury, volunteered to participate in the study. Three maximal effort SLTH test trials on two different surfaces (court, synthetic turf) were collected and analyzed using 3D motion analysis techniques. Outcome variables included SLTH test distances and LSI values and sagittal plane kinematics including trunk, hip, knee and ankle range of motion (ROM) during the last two landings of each SLTH test trial. The second landing involves an absorption phase and propulsion phase in contrast to the final landing which involves absorption and final balance on the single leg. Paired t-tests were used to determine differences between surfaces in hop distance and LSI values. Two-way repeated measures ANOVA were used to determine differences between surfaces in kinematic variables. The total SLTH test distance was not statistically different between the court (4.11±0.47m) and turf (4.03±0.42m, p=0.47) surfaces. LSI for the court surface was 100.8±3.0% compared to 99.7±3.0% for turf surface, which was not statistically different (p=0.30). Knee flexion ROM was significantly less (p=0.04) on the turf compared to the court surface during the second landing. Ankle flexion range of motion was also significantly less (p=0.03) during the second landing on turf compared to court. The authors concluded that the type of surface influenced landing kinematics but not total SLTH test distance. When evaluating the quality of landings during a SLTH test, it may be warranted to observe each type of landing and the type of surface used during single leg tests.

Abstract  |  IJSPT-15_6-07-Ford

Biomechanical Measures During Two Sport-Specific Tasks Differentiate Between Soccer Players Who Go on To Anterior Cruciate Ligament Injury and Those Who Do Not: A Prospective Cohort Analysis.
Authors:  Dix C, Arundale A, Silvers-Granelli H, Marmon A, Zarzycki R, Snyder-Mackler L

Decelerating and cutting are two common movements during which non-contact anterior cruciate ligament (ACL) injuries occur in soccer players. Retrospective video analysis of ACL injuries has demonstrated that players are often in knee valgus at the time of injury. The purpose of this study was to determine whether prospectively measured components of valgus collapse during a deceleration and 90 degree cut can differentiate between collegiate women’s soccer players who go on to non-contact ACL injury. Fifty-one NCAA women’s soccer players completed motion analysis of a deceleration and 90 degree cut before the competitive season. Players were classified as Injured (noncontact ACL injury during the season) or Uninjured at the end of the season. Differences between groups for peak hip adduction, internal rotation, and knee abduction angles, and knee valgus collapse were analyzed with a MANOVA. Four non-contact ACL injuries were reported at the end of the season. There was a significant difference between groups for hip adduction angle during the 90 degree cut (p=0.02) and deceleration (p=0.03). Players who went on to ACL injury were in more hip adduction. The authors concluded that the hip adduction angle is larger in players who go on to ACL injury than those who do not during two sport-specific tasks. The components of knee injury prevention programs that address proximal control and strength are likely crucial for preventing ACL injuries.

Abstract  |  IJSPT-15_6-08-Dix

Validity of an MRI-Compatible Motion Capture System For Use With Lower Extremity Neuroimaging Paradigms.
Authors: Anand M, Dickfuss JA, Bonnette S, Short I, Hurn M, Grooms DR, Myer GD

Emergent linkages between musculoskeletal injury and the nervous system have increased interest to evaluate brain activity during functional movements associated with injury risk. Functional magnetic resonance imaging (fMRI) is a sophisticated modality that can be used to study brain activity during functional sensorimotor control tasks. However, technical limitations have precluded the precise quantification of lower-extremity joint kinematics during active brain scanning. The purpose of this study was to determine the validity of a new, MRI-compatible motion tracking system relative to a traditional multi-camera 3D motion capture system for measuring lower extremity joint kinematics. Fifteen subjects (9 females, 6 males) performed knee flexion-extension and leg press movements against guided resistance while laying supine. Motion tracking data were collected simultaneously using the MRI-compatible and traditional multi camera 3D motion systems. Participants’ sagittal and frontal plane knee angles were calculated from data acquired by both systems. Resultant range of angular movement in both measurement planes were compared between both systems. Instrument agreement was assessed using Bland-Altman plots and intraclass correlation coefficients (ICC). The system demonstrated excellent validity in the sagittal plane (ICCs>0.99) and good to excellent validity in the frontal plane (0.84<ICCs<0.92). Mean differences between corresponding range of angular movement measurements ranged from 0.186° to 0.295°. The present data indicate that this new, MRI-compatible system is valid for measuring lower extremity movements when compared to the gold standard 3D motion analysis system. As there is growing interest regarding the neural substrates of lower extremity movement, particularly in relation to injury and pathology, this system can now be integrated into neuroimaging paradigms to investigate movement biomechanics and its relation to brain activity.

Abstract  |  IJSPT-15_6-09-Anand

Sprint Performance in Football (Soccer) Players With and Without A Previous Hamstring Strain Injury: An Explorative Cross-Sectional Study.
Authors: Ishoi L, Thorborg K, Holmich P, Krommes K

Hamstring strain injuries are common in many sports. Following a hamstring injury, deficits in peak and explosive strength may persist after return to sport potentially affecting sprint performance. Assessment of repeated-sprint ability is recognized as an important part of the return to sport evaluation after a hamstring injury. The purpose of this exploratory cross-sectional study was to compare sprinting performance obtained during a repeated-sprint test between football players with and without a previous hamstring strain injury. Forty-four fully active sub-elite football players, 11 with a previous hamstring strain injury during the preceding 12 months (cases; mean age, SD: 25.6 ± 4.4) and 33 demographically similar controls (mean age, SD: 23.2 ± 3.7), were included from six clubs. All players underwent a repeated-sprint test, consisting of six 30-meter maximal sprints with 90 seconds of recovery between sprints. Sprint performance was captured using high-speed video-recording and subsequently assessed by a blinded tester to calculate maximal sprint velocity, maximal horizontal force, maximal horizontal power, and mechanical effectiveness. For maximal sprint velocity, a significant between-group difference was seen with players having a previous hamstring injury showing highest values over six sprints (mean difference: 0.457 m/s, 95% CI: -0.059-0.849, p=0.025). No other differences were observed for the remaining sprint variables. The authors found that repeated-sprint performance was not impaired in football players with a previous hamstring strain injury; in fact, higher mean maximal sprinting velocity was found in players with compared to without a previous hamstring injury. The higher sprinting velocity, which likely increases biomechanical load on the hamstring muscles, in previously injured players may increase the risk of recurrent injuries.

Abstract  |  IJSPT-15_6-10-Ishol

Iliotibial Band Syndrome in Cycling: A Combined Experimental-Simulation Approach For Assessing The Effect of Saddle Setback.
Authors: Menard M, Lacouture P, Domalain M

Despite abundant literature, the treatment of iliotibial band syndrome (ITBS) in cyclists remains complicated as it lacks evidence-based recommendations. The aim of this study was to develop a musculoskeletal modelling approach that investigates three potential biomechanical determinants of ITBS (strain, strain rate, and compression force) and to use this approach to investigate the effect of saddle setback. An existing 3D lower-body musculoskeletal model was adapted to cycling and to the computation of three putative pathomechanisms responsible for ITBS: ITB strain, ITB strain rate, and compression force between ITB and the lateral femoral epicondyle (LFE). Lower limb kinematics recorded from ten well-trained healthy cyclists served as input data of the model. Cyclists pedalled at a steady state (90rpm and 200W) on an ergometer, and three different saddle setback conditions were tested. The theoretical combined influence of hip and knee joint angles on ITBS was investigated and analysed through the lens of individual pedalling technique. ITB-LFE compression force was the only parameter significantly affected by saddle setback and supports the hypothesis that compression force is likely to be a determinant factor in ITBS etiology. Furthermore, results showed that ITB-LFE compression force increases in individuals whose pedalling technique exacerbates hip extension-adduction and/or knee extension-internal rotation. This approach has the potential to be advantageously implemented as an additional tool to help diagnose/correct potentially harmful sport techniques and optimize equipment setup/design.

Abstract  |  IJSPT-15_6-11-Menard

Strength and Fatigue Measurements of the Hip Flexor and Hip Extensor Muscles: Test-Retest Reliability and Limb Dominance Effect.
Authors: Krantz MM, Astrom M, Drake AM

Standardized testing of hip muscle strength and fatigue in the sagittal plane is important for assessing, treating and preventing a number of trunk and lower extremity pathologies. Furthermore, individuals displaying asymmetries of muscle strength between limbs are more likely to sustain an injury.  The purpose of this article was to evaluate the test-retest reliability of isometric strength and isokinetic fatigue measurements of the hip flexor and hip extensor muscles, and to examine whether there is a significant limb dominance effect on strength, fatigue and flexor-extensor ratios. To evaluate reliability, 30 healthy individuals (33.2 +/¬- 13.1 years) were included. On a separate occasion, 24 healthy individuals (29.0 +/- 10.3 years) participated to assess between-limb differences. Reliability was established using intraclass correlation coefficients (ICCs), standard error of measurements (SEM) and minimal detectable change (MDC). Isometric strength (best peak torque of three maximal contractions; Nm/kg), isokinetic fatigue (total work of 20 consecutive maximal concentric flexor-extensor contractions at 120°/s; Joule/kg), and flexor-extensor ratios, were recorded using a Biodex dynamometer. Reliability was good-to-excellent (ICCs>0.83) and measurement errors were acceptable (SEM<13.6% and MDC%<37.8%). No significant between-limb differences in strength, fatigue and flexor-extensor ratios were detected. The authors concluded that isometric strength and isokinetic fatigue of the hip flexor and hip extensor muscles can be reliably assessed in healthy individuals using the Biodex dynamometer. Limb dominance did not significantly affect strength, fatigue, or flexor-extensor ratios.

Abstract  |  IJSPT-15_6-12-Drake

Balance Training: Does Anticipated Balance Confidence Correlate with Actual Balance Confidence for Different Unstable Objects?
Authors: Cheatham SW, Chaparro G, Kolber M

Sports rehabilitation professionals often prescribe unstable objects for balance training. Unfortunately, there is a lack of measurement of balance confidence when incorporating these objects. Currently, there is no consensus on the optimal balance confidence measure or proposed progression of unstable objects. Understanding the influence of balance confidence on task performance using unstable objects may help professionals better prescribe a balance training program. The primary purpose of this investigation was to explore the correlation between anticipated and actual balance confidence on different unstable objects during static double leg and single leg stance. The secondary purpose was to explore the correlation between anticipated and actual unstable object difficulty rankings. Sixty-five active, healthy adults (M=35, F=30) (mean age=24.38 ± 3.56) underwent two testing sessions. During session one, participants took an online survey, rating their anticipated balance confidence after observing images of different unstable objects. During session two, participants stood on each unstable object under two conditions (static double leg stance and single leg stance) and rated their actual balance confidence. The main outcome measure was an ordinal balance confidence score adapted from the activities-specific balance confidence scale. Statistical analysis included subject demographic calculations and appropriate non-parametric tests. For the double leg stance and single leg stance conditions, there was a very strong correlation between anticipated and actual balance confidence scores on the stable surface (ρ =1.0, p= <.001). There was a weak correlation between scores for foam pad, air-filled discs, Bosu® (dome up), Bosu® (dome down), and wobble board for both conditions. For unstable object rankings, there was a very strong correlation between scores (ρ=1.0, p= <.001). The objects were ranked by perceived difficulty as follows: Level 1 (easy)- ground, Level 2- foam pad, Level 3- air-filled discs, Level 4- Bosu®, and Level 5 (difficult)- wobble board. The study findings suggest that actual measures of balance confidence may provide insight into a patient’s confidence level and may help with prescribing and progressing their program. The suggested unstable object difficulty rankings may help professionals better match the objects to their patients to produce optimal outcomes.

Abstract  |  IJSPT-15_6-13-Cheatham

Consistency of Dynamic Knee Valgus Kinematics And Pain Across Functional Tasks In Females With patellofemoral Pain: A Cross-Sectional Study.
Authors: Scholtes SA, Salsich GB

Dynamic knee valgus has been associated with patellofemoral pain during high-level tasks, however, repeated lower-level stresses may be an alternative pain mechanism. The primary purpose of the current study was to examine the consistency of dynamic knee valgus and task-elicited pain demonstrated by females with PFP across four common functional tasks (stair ascent, stair descent, sit-to-stand, and stand-to-sit). A secondary purpose was to assess the correlation between the clinical test of single-limb squat and functional tasks. The author hypothesis was that females with patellofemoral pain will demonstrate a positive relationship in magnitude of dynamic knee valgus and task-elicited pain across functional tasks. Individuals who demonstrated greater dynamic knee valgus and task-elicited pain during the clinical test of single-limb squat would demonstrate greater dynamic knee valgus and task elicited pain during stair ascent/descent and sit-to-stand/stand-to-sit tasks. Twenty-three women with patellofemoral pain (age: 21.8 SD 3.7 years; BMI: 22.2 SD 2.0 kg/m2) participated. Three-dimensional kinematic data were captured during task completion. Hip and knee frontal and transverse plane angles at 45° of knee flexion, and pain using a visual analog scale, were assessed during single-limb squat, stair ascent/descent, and sit-to-stand. Pearson product-moment correlation coefficients were calculated to examine between-task relationships for each variable at the pre-intervention assessment. Correlation coefficients between tasks ranged from 0.23-0.76 for hip frontal plane measures (7/10 significant relationships, p<0.02), 0.31-0.90 for hip transverse plane measures (7/10 significant, p<0.01), 0.87-0.95 for knee frontal plane measures (10/10 significant, p<0.01), and 0.54-0.86 for knee transverse plane measures (10/10 significant, p<0.01). Correlations spanned 0.59-0.85 for pain during tasks (10/10 significant, p<0.01). The authors concluded that females with patellofemoral pain demonstrated positive correlations in dynamic knee valgus kinematics and task-elicited pain across five tasks. Movement and pain during the clinical test of single-limb squat test also was correlated with movement and pain during the functional tasks of stair ascent/descent and sit-to-stand.

Abstract  |  IJSPT-15_6-14-Scholtes

Timeline of Gains in Quadriceps Strength Symmetry and Patient-Reported Function Early after ACL Reconstruction.
Authors: Pottkotter K, DiStasi S, Schmitt L, Magnussen R, Paterno M, Flanigan D, Kaeding C, Hewett T

Quadriceps weakness is a predictor of long-term knee function and strength recovery can vary from months to years after anterior cruciate ligament reconstruction (ACLR). However, few studies evaluate quadriceps strength and self-reported function within the first several weeks after ACLR.  The purpose of this study was to examine changes over time in quadriceps strength symmetry, quadriceps peak torque, and self-reported knee function prior to and at six, 12, and 24 weeks post-ACLR. The hypotheses were 1) quadriceps strength symmetry, bilateral quadriceps peak torque, and patient-reported function would improve over time from pre-ACLR to 24 weeks post-ACLR and 2) significant improvements in patient-reported function, but not strength symmetry, would occur between time points. Thirty participants completed four testing sessions: pre-surgery and six, 12, and 24 weeks post-ACLR. Isometric quadriceps strength testing was performed at six weeks and isokinetic quadriceps strength was measured at all other testing points. Quadriceps index was calculated to evaluate between limb quadriceps strength symmetry. The Knee injury and Osteoarthritis Outcome Score (KOOS) and International Knee Documentation Committee Subjective Knee Evaluation Form (IKDC) were administered at each time point. A repeated-measures analysis of variance evaluated changes over time, with post-hoc comparisons to determine at which time-point significant changes occurred. Quadriceps strength symmetry, involved limb quadriceps peak torque, and all patient-reported outcome scores increased over time (p<0.02). Post-hoc tests showed that neither self-reported outcomes, nor quadriceps index improved between pre-surgery and six-weeks post-ACLR. From six to 12 weeks post-ACLR, scores on IKDC and KOOS Pain, Symptoms, Quality of Life, and Sport subscales improved (p≤0.003). From 12 to 24 weeks post-ACLR, quadriceps strength symmetry, involved limb quadriceps peak torque, KOOS-Symptoms, Quality of Life, and Sport subscales and the IKDC improved (p≤0.01). Uninvolved limb quadriceps peak torque did not change across any time point (p≥0.18). The authors found that patient-reported knee function increased between six and 24 weeks post-ACLR, while increases in involved limb quadriceps strength and quadriceps strength symmetry were not noted until 12-24 weeks post-ACLR.

Abstract  |  IJSPT-15_6-15-Pottkotter

Less Than Half of ACL-Reconstructed Athletes Are Cleared For Return To Play Based On Practice Guideline Criteria: Results From A Prospective Cohort Study.
Authors:  van Melick N, Hoogeboom TJ, Pronk Y, Rutten B, van Tienen TG, Nijhuis-van der Sanden MWG, van Cingel REH

A recently published Dutch practice guideline emphasizes criterion-based rehabilitation after anterior cruciate ligament reconstruction (ACLR) instead of time-based. As a consequence of this criterion-based rehabilitation, return to play is only suggested when athletes meet specific return to play (RTP) criteria. The goal of this prospective observational study was to analyze if physical therapists adhere to ACLR practice guideline RTP criteria for testing and return to sport decisions, and to explore whether there is a difference in adherence between physical therapists specialized in sports versus those who are not. When the treating physical therapist cleared an athlete for RTP after ACLR, the primary researcher performed RTP measurements according to the ACLR practice guideline to investigate if all nine quantitative and qualitative RTP criteria were met. Of the 158 athletes (54 females and 104 males, mean age 24±6 years, 12±3 months after surgery), 69 (44%) had performed the RTP measurements with their primary physical therapist. Of the athletes tested by their primary physical therapist 23% met all RTP criteria compared to 10% of the athletes who were not tested at all by their primary physical therapist (p=0.026). Of the athletes rehabilitating with a sports physical therapist, 52% had been tested by their primary physical therapist compared to 34% of the athletes rehabilitating with a non-sports physical therapist (p=0.024). Only 44% of the athletes were tested according to the guideline RTP criteria and only 23% of them were given an RTP advice consistent with the ACLR guideline. Although sports physical therapists adhered to the guideline more often than non-sports physical therapists, the adherence is still alarmingly low. More attention for the implementation of ACLR guidelines and RTP criteria is needed.

Abstract  |  IJSPT-15_6-16-van Melick

Electromyographic Analysis of Gluteal Recruitment: An Exploration of Activation During Jumping Tasks.
Authors: Heick JD, Talkington M, Jain T

Inability to maintain proper alignment of the pelvis and femur due to gluteal muscle weakness has been associated with numerous lower extremity pathologies. Therefore, many lower extremity rehabilitation and injury prevention programs employ exercises that target gluteal muscle strength and activation. While information regarding muscle activation during exercises that are typically done in the beginning stages of rehabilitation is available, evidence regarding the gluteal muscle activity during more functional and advanced exercises used during later stages of rehabilitation is sparse. The purpose of this study was to explore the recruitment of the gluteal muscles during jumping tasks in healthy participants to determine which jumping exercise best elicits gluteal muscle activation. Eighteen healthy recreational athletes (23.5±3.8 years, 8M/10F, 67.56±3.2 inches, 66.73±9.5 kg) completed three trials of four jumping tasks: hurdle jump, split jump, V2 lateral jump, and cross-over jump in random order. Surface EMG electrodes were placed on each participant’s bilateral gluteus medius (GMed) and maximus (GMax) to measure muscle activity during the jumping tasks. Maximal voluntary isometric muscle contraction (MVIC) was established for each muscle group in order to express each jumping task as a percentage of MVIC and allow standardized comparison across participants. EMG data were analyzed for all jumps using a root-mean-square algorithm and smoothed with a 62.5 millisecond time reference. Rank ordering of muscle activation during jumping tasks was performed utilizing the peak percent MVIC recorded during each jumping task. Three of the jumping tasks produced greater than 70% MVIC of the GMed muscle. In rank order from highest EMG value to lowest, these jumping tasks were: crossover jump (103% MVIC), hurdle jump (93.2% MVIC), and V2 lateral jump (84.7% MVIC). Two of the exercises recruited GMax with values greater than 70% MVIC. In rank order from highest EMG value to lowest, these jumping tasks were: hurdle jump (76.8% MVIC) and split jump (73.1% MVIC). Only the hurdle jump produced greater than 70% MVIC for both GMed and GMax muscles. The jumping task that resulted in greatest activation of the GMed was the crossover jump, while hurdle jump led to the greatest activation of the GMax. The high %MVIC for the GMed during the crossover jump may be attributed to lack of maximal effort or lack of motivation during performance of maximal contractions during the manual muscle testing. Alternatively, substantial co-contraction of core muscles during the crossover jumping task may have led to higher values.

Abstract  | IJSPT-15_6-17-Heick

Functional Movement Screen (FMS) Scores Do Not Predict Overall or Lower Extremity Injury Risk in Collegiate Dancers.
Authors: Coogan SM, Schock CS, Hansen-Honeycutt J, Caswell S, Cortes N, Ambegaonkar JP

Dance is a physically demanding activity, with 50-85% of dancers suffering injury during a single performance season. The majority of dancers’ injuries are in the lower extremity (LE) and chronic in nature. These injuries often arise when causal factors are not identified early and addressed before they ultimately result in an injury. Practitioners often use movement screens such as the Functional Movement Screen™ (FMS™) to detect and quantify kinetic chain dysfunction. Prior researchers have suggested that these screens can stratify at-risk individuals and allow practitioners to devise targeted interventions to reduce their injury risk. However, whether the FMS™ can identify at-risk dancers remains unclear. Thus, the purpose of this study was to examine whether FMS™ scores predicted injury risk in collegiate dancers. In this prospective study, 43 collegiate dance majors (34 female, 9 male; 18.3+0.7yrs; 163.9+7.3cm; 60.8+8.1kg) in a program which emphasizes modern dance at the start of the academic year were scored on the seven FMS™ movements as described in prior literature. Separate Receiver Operator Characteristic (ROC) curve analyses examined whether composite FMS™ score predicted (1) Overall or (2) LE injury status. The subjects FMS scores were 16.2+1.7 (range=11–19). Twenty dancers were injured, whereas 23 remained injury-free. Injured dancers had 55 overall (1.28 injuries/dancer) and 44 LE injuries (1.02 LE injuries/dancer). FMS score did not predict overall (AUC=.28, SE=.08, p=.02, 95%CI=.13-.43) or LE injury risk (AUC=.38, SE=.1, p=.21, 95% CI=.21-.56). While nearly half of the dancers in this group suffered from injury over the year, composite FMS™ scores did not predict overall or LE injury risk in collegiate dancers. Dancers face unique and challenging physical demands that distinguish them from traditional sport-athletes including greater ranges of movement during performance. Thus, the FMS™ may not be sensitive enough to distinguish ‘appropriate’ from ‘excessive’ mobility and adequately identify injury risk in dancers. Overall, it is suggested that practitioners should use caution before using the FMS™ as a primary screening mechanism to identify collegiate dancers at overall or LE injury risk.

Abstract  |  IJSPT-15_6-18-Coogan

Reliability of Center of Pressure-Based Measures during Dual-Task Postural Control Testing in a Youth Population.
Authors: Campolettano ET, Madigan ML, Rowson S

Dual-task assessments can identify changes in postural control during recovery from a concussion. However, developing postural control in children presents a challenge when using adult balance assessments to examine children. The purpose of this study was to investigate the reliability of a cognitive dual-task postural control testing protocol among a youth sample with no history of concussion or exposure to head impacts. Testing comprised nine 120 second trials of standing on a force plate collecting data at 250 Hz. Test conditions included no dual-task, counting backwards by 2, counting backwards by 3, listening, and the Stroop test. Subjects completed each test with open and closed eyes, except for the Stroop test. The force plate was used to measure the subjects’ center of pressure (COP) trajectory.  Nine healthy, youth subjects (average age: 11.6 ± 0.5 years) with no history of concussion or exposure to head impacts participated. Reliability was good (>0.6) or excellent (>0.75) for COP speed, sway, and sample entropy measures for several test conditions. The eyes open, no task condition produced the lowest COP measures. No differences were observed between the other dual-task conditions. The authors concluded that given its high measures of reliability, this dual-task protocol might be able to detect postural control changes in concussed youth athletes.

Abstract  |  IJSPT-15_6-19-Campolettano

Deep Neck Flexors Impact Rectus Abdominis Muscle Activity During Active Straight Leg Raising.
Authors:  Takasaki H, Okubo Y

Active straight leg raising (ASLR) is commonly performed to test fundamental movement competency. Head control or positioning can affect the abdominal muscle activity during movements. The purpose of this study was to investigate whether abdominal muscle activity differs when the head is extended or when deep neck flexor (DNF) muscles are selectively activated during the ASLR. Participants were included based on the following criteria: 1) age>17 years; 2) no spinal or lower extremity pain in the prior month; 3) the vertical line of the malleolus in an elevated the lower limb resides below the knee joint line of a non-moving lower limb during ASLR and above during a passive straight leg raising in each lower limb; and 4) no history of diagnosed spinal deformities or central nervous system disorders. Participants with >39% reference voluntary contraction in the sternocleidomastoid muscle during the craniocervical flexion test (CCFT) of 24 mmHg target were excluded from the analyses. Right ASLR was repeated in each of the following three head conditions in a random order: 1) neutral head position, 2) head extended by 25°, and 3) CCFT maintained with a 24 mmHg target. Among the three head conditions, the relative latency for the onset of the right rectus femoris (RF) muscle during the right ASLR and the muscle activity amplitude for 50ms were compared after the onset of RF muscular activity in the following muscles: left rectus abdominis (RA), bilateral external obliques, bilateral internal obliques, and left gluteus maximus muscles. Data from 31 participants (21 women and 10 men, mean age=22.5 years) were analyzed. The relative latency of the left RA (Hedges’ g=0.39, p=.038) was higher in the CCFT condition (mean±SD=112.1ms±86.0ms) than that in the neutral head condition (82.9ms±58.6ms). However, no difference (all p>.05) was observed in other measures between the groups. In people with impaired movement competency in ASLR, head extension did not alter the abdominal muscle activities in ASLR. However, selective activation of the DNF muscles delayed the onset of RA muscle activity during the ASLR.

Abstract  |  IJSPT-15_6-20-Takasaki

Core Stability Muscle Activity During Standing Lower Body Twisting Exercises.
Authors: Tsuruike M, Munson M, Hirose N, Nishime RS

Little is known about the activity of the abdominal internal oblique (IO) and lumbar multifidus (LM) muscles relative to kinetic chain exercises performed in a standing position. The purpose of this study was to identify the activity of the IO and the LM muscles during weight-bearing exercises. The authors hypothesized that IO and LM muscle activity would vary with lower body positions during the kinetic chain exercises. Nineteen healthy, young, active subjects volunteered to participate. The electromyographic (EMG) activity (via surface EMG) of the abdominal external oblique (EO), IO, and LM muscles on both sides and the rectus femoris and semitendinosus muscles on the dominant side was determined during rhythmical lower body twisting exercise with three lower body positions: straight leg (SL), athletic position (AP), dynamic knee extension (DE) at two exercise speeds: 150 and 90 beats per min. These were reported as % maximum voluntary contraction. Mean EO, IO, and LM muscle activities were also compared with those of common core stability exercises. IO EMG activity was significantly greater in SL than that of AP (p < 0.05). In contrast, LM EMG activity was significantly greater in the DE position than that of both SL and AP positions (p < 0.05). The authors concluded that IO muscle activity could be attenuated by the contraction of lower body extensor muscles during the standing position.

Abstract  |  IJSPT-15_6-21-Tsuruike

Can Proximal Hip Strength and Dynamic Control Differentiate Functional Ankle Stability Classifications?
Authors: Mulligan EP, DeVahl J

Ankle instability can be problematic in an active population with multiple risk factors associated with recurrence. The aim of this study was to determine if deficits in weight-bearing and non-weight bearing assessment of hip strength or dynamic balance in lower extremity reaching tasks from flat and inclined surfaces can differentiate subjects classified as controls, ankle sprain copers, or those with chronic, recurrent ankle sprains. A convenience sample of 60 subjects was classified into control, coper, or chronic ankle sprain groups based on the results of the Identification of Functional Ankle Instability Questionnaire. Subjects were tested for peak force production of their hip extensors, hip abductors, and a composite of hip extension and external rotation while in a standing position using a hand-held dynamometer. Additionally, each subject performed a modified Star Excursion Balance Test in anterior, posterolateral, and posteromedial directions from both a flat and 15 degrees inverted stance position. One-way analysis of variance was calculated for between group differences of hip strength and balance reach ability and ankle stability classification. Pearson product-moment correlation coefficients were derived to evaluate relationships between hip strength and dynamic balance tests. Twenty-one subjects were assigned to the control group, 23 to the coper group, and 16 to the chronic group. There were no significant differences between groups in self-report of Foot and Ankle Ability Measures or Tegner activity levels. Mean hip strength was not significantly different between ankle sprain classification groups (p = 0.66 – 0.82). The mean limb symmetry index for hip strength comparing injured and uninjured ankles was nearly symmetrical in all ankle stability groups (p = 0.34 – 0.97). The same symmetry was present when comparing injured and uninjured abilities for all dynamic balance reach tasks from both flat and inclined surfaces. (p = 0.16 – 0.62). There was a fair relationship between hip extension and weight-bearing hip extension/external rotation strength and the posteromedial and posterolateral reach tasks with correlation coefficients in the range of 0.33 – 0.43. The authors concluded that performance measures of tri-planar, static, isometric hip strength and lower extremity reach in dynamic balance tasks could not differentiate subjects without a history of injury from those subjects with one or more lateral ligamentous ankle sprains.

Abstract |  IJSPT-15_6-22-Mulligan

Assessment of Humeral Torsion By Palpation In Baseball Pitchers: A Validation Study.
Authors: Yaari LS, Mullaney MJ, Fukunaga T, Thein R, McHugh MP, Nicholas SJ

Greater humeral retroversion has been associated with shoulder and elbow injuries. Methods for measuring torsion include radiography, computed tomography (CT) and sonography (US) which may be costly or unavailable. A palpation method might be a reliable alternative to imaging techniques. The purpose of the current study was to examine the construct validity of the palpation technique for humeral torsion by (1) determining if a side-to-side difference in HT could be detected in a cohort of baseball pitchers using the palpation technique and (2) compare the side-to-side difference in HT obtained through the palpation method to the US method. The authors hypothesized that the clinical assessment of humeral torsion (HT) by palpation is reliable and is as accurate as sonographic HT measurements among overhead athletes. Twenty collegiate and high school pitchers were assessed. Bilateral shoulder passive external rotation (ER) and internal rotation (IR) range of motion were measured. Humeral torsion was indirectly measured using sonographic and palpatory methods. Paired t-tests were used to determine HT side-to-side difference measured by US versus palpation. Pearson’s correlation coefficient (r) was used to determine the relationship between HT side-to-side difference detected by palpation and US, and relationships among IR and ER of the shoulder and HT side to-side difference measurements. There was significantly greater HT in dominant versus nondominant arm assessed by both palpation (5°±5, p=0.0004) and ultrasound (9°±11, p=0.0007). There was a positive correlation between both methods of HT measurement (r = 0.522, p=0.018). Palpation significantly underestimated HT as compared to US measurements (difference 4°±9, p=0.048). Difference in IR between shoulders correlated with HT measured by palpation (r=-0.651, p=0.002) and US (r=0.569, p=0.009). Increased ER in the dominant versus nondominant arm correlated with the side-to-side difference in HT measured by both palpation (r= 0.509, p=0.02) and US (r= 0.602, p=0.005). The authors found greater HT on the dominant versus nondominant shoulder via palpation indicated this method can be used to assess HT in pitchers. HT assessed by palpation correlated with HT assessed by US. However, the magnitude of side-to-side difference in HT was smaller with palpation compared to US, and the two techniques should not be used interchangeably. Nevertheless, assessment of HT via palpation is a reliable and practical method and its use should be encouraged.

Abstract  |  IJSPT-15_6-23-Yaari

Correlation Between the Kerlan-Jobe Orthopadic Clinic Screen and Subacromial Impingement Test-Item Cluster in Collegiate Baseball Pitchers: A Pilot Study.
Authors: Rich A, Stickley L

Shoulder injuries in baseball related to throwing account for 60% of all baseball injuries and 75% of those throwing injuries occur in pitchers. Impingement is the beginning of a continuum of rotator cuff pathology that can result in pain and disability in pitchers. Identification of self-reported measures and clinical tests that can indicate early pathology of shoulder impingement is needed for overhead athletes. Early identification of shoulder impingement is important to the long-term health and function of these athletes. The purpose of this study was to determine if a correlation exists between self-reported pain and disability using the Kerlan-Jobe Orthopedic Clinic (KJOC) score and the Park Test-Item Cluster (TIC) for subacromial impingement in college baseball pitchers. The authors hypothosized that there will be a correlation 1) between the KJOC score and the TIC by Park and 2) between the KJOC and the Hawkins-Kennedy impingement, the painful arc, and the infraspinatus muscle strength tests individually. Twenty-one collegiate baseball pitchers completed the KJOC and then were tested using the Park test-item cluster. Kruskal-Wallis was used to test the relationship of individual demographics with KJOC scores. Spearman rho correlation was used to determine if the number of positive clinical tests in the Park TIC or with the individual tests within the TIC correlated with scores on the KJOC. No significant relationships between KJOC scores and demographics were found. A significant moderate-to-good relationship was found between the painful arc test and the KJOC (r = -.601, p= 0.00) and a significant fair correlation was found between the number of positive tests within the Park TIC and KJOC (r = -.426, p = 0.05). No significant relationships were found between the Hawkins-Kennedy and KJOC (r = -.348, p= 0.12) or between the infraspinatus strength test and KJOC (r = -.040, p= 0.86). The correlations between the painful arc test and the number of positive impingement tests with the composite score on the KJOC suggests a relationship between these two outcome measures, shoulder irritability, and decreased function in collegiate baseball pitchers. Of the three tests included in the Park TIC, the painful arc test was the only one with an independent significant correlation to the KJOC. The combination of impairment-specific cluster testing and an activity-focused self-assessment tool could be utilized to identify potential pathology and alert the medical professional that assessment and intervention are necessary.

Abstract  |  IJSPT-15_6-24-Rich

Descriptive Profile of Shoulder Range of Motion and Strength in Youth Athletes Participating in Overhead Sports.
Authors: Oliver GD, Downs J, Barbosa GM, Camargo PR

The unilateral and repetitive nature of overhead sports, often result in a biomechanical overload of the upper extremity. Understanding the musculoskeletal shoulder range of motion (ROM) and strength patterns in the youth sports of baseball, softball, and tennis could assist injury prevention screening and further the development of conditioning and rehabilitation programs. The purpose of this study was to generate a descriptive profile of shoulder musculoskeletal characteristics and determine whether bilateral differences in shoulder ROM exist in youth baseball, softball, and tennis athletes. A secondary aim was to determine whether shoulder rotational adaptations are correlated with playing position, sport, or years of experience. A total of 136 competitive youth overhead athletes (baseball: n=51: softball: n=63; and tennis: n=22) participated. Bilateral shoulder passive internal (IR) and external (ER) passive ROM and external rotation strength were measured using inclinometer and handheld dynamometer. Significant differences (p<.001) in bilateral shoulder ROM and ER strength was found between the athletes in the three sports. Post-hoc test revealed tennis athletes had greater bilateral shoulder ROM than both the baseball and softball athletes, but baseball and softball athletes had greater bilateral ER strength than tennis athletes. There were no differences between baseball and softball athletes. Additionally, tennis athletes had greater bilateral internal rotation and total ROM but less ER strength than baseball pitchers, baseball positional athletes, softball pitchers, and softball positional athletes. There were no significant differences between positions and baseball and softball athletes. There were no significant correlations between playing position, sport, or years of experience. Therefore, the results of this study showed differences in shoulder passive ROM and strength adaptations between youth tennis, baseball, and softball athletes. The descriptive nature of this study is impactful as it presents specific ROM adaptions seen in this population. Future research is needed to further evaluate if the “at risk” ROM identified in older populations holds true in the youth population.

Abstract  |  IJSPT-15_6-25-Oliver

An Assessment of the Contractile Properties of the Shoulder Musculature in Elite Volleyball Players Using Tensiomyography.
Authors: Parmar A, Scott M, Brand C, Jones TW

In volleyball, offensive (Hitters) and defensive players (Non-Hitters) perform differing actions that vary both kinematically and in terms of intensity. This may impose contrasting demands on the musculature involved in performing these actions. Previous research has identified differences in the muscle activation and contractile properties of the lower-body musculature between positions. Additionally, asymmetries between dominant and non-dominant limbs of the upper-body musculature has been observed in athletes performing overhead movements. The aim of this study was to use Tensiomyography (TMG) to examine the contractile properties of the shoulder musculature in elite volleyball players. Thirty-one elite volleyball players participated in this study (Age: 23 ± 2 yrs, Body Mass: 76.5 ± 9.8 kg, Stature: 181 ± 9.3 cm), 26 of which displayed right-limb dominance and five displayed left-limb dominance. Contractile properties of the shoulder musculature including the anterior deltoid (AD), biceps brachii (BB), posterior deltoid (PD), and the upper trapezius (UT) were assessed bilaterally using TMG measures on one occasion prior to any training or exercise. The contractile measures provided by TMG included the maximal displacement (Dm), contraction time (Tc), delay time (Td), sustain time (Ts), and the relaxation time (Tr). No statistically significant differences were observed between positions or limbs, except that Hitters displayed a significantly lower Ts of the left AD compared to Non-hitters (p = 0.01, ES = 1.02), and significant differences between dominant and non-dominant sides in the Td of the UT in Non-hitters were present (p = 0.05, ES = 0.8). These data suggest that irrespective of playing position and limb dominance, contractile properties of the shoulder musculature in elite volleyball players, as measured using TMG, display few significant differences.

Abstract  |  IJSPT-15_6-26-Parmer

Forearm Position Matters During Eccentric Shoulder Exercises: An EMG Recruitment Study With Implications for Rehabilitation.
Authors: Hedt C, Lambert BS, Daum J, Pearson JM, McCulloch PC

Eccentric exercise has demonstrated great utility in the rehabilitation of various shoulder pathologies. Research on the electromyographic (EMG) activity of the shoulder musculature during these activities is limited, however. Furthermore, no studies have observed how forearm positioning during exercise affects EMG output. The purpose of this study was to examine the degree of specific muscle recruitment among commonly used eccentric exercises in rehabilitation of the upper extremity and shoulder. Secondarily, the authors hypothesized that different hand/forearm positions would alter EMG activity within the targeted musculature during a given exercise. This study analyzed surface EMG data obtained from 10 healthy individuals during five eccentric exercises of the dominant extremity, performed in a randomized order: side-lying eccentric horizontal abduction (SL ER), half-kneeling weighted ball decelerations (BALL DC), seated eccentric external rotation in scaption (STD ER), standing eccentric external rotation at 0deg (STND ER), supine eccentric external rotation at 90deg (SUP ER). Each exercise was performed with two to three forearm position variants commonly used in clinical environments: neutral, pronation, and/or supination. EMG data were collected from the upper trapezius, infraspinatus, teres minor, latissimus dorsi, and anterior/middle/posterior deltoid. Data were analyzed for each individual exercise and within each muscle using a mixed-model ANOVA repeated across forearm position. Significant interactions were followed by a Bonferroni post-hoc test for pairwise comparisons. Effect size was calculated for all significant pairwise comparisons using a Cohen’s d statistic. Significant differences in EMG activity for the selected musculature exist between forearm positions for four of the five exercises and Cohen’s d effect sizes 0.178 – 1.159. The authors found that specific eccentric shoulder exercises activate muscles of the shoulder complex differently based on forearm positioning.

Abstract  |  IJSPT-15_6-27-Hedt

The Relationship of Range of Motion, Hip Shoulder Separation, and Pitching Kinematics.
Authors: Bullock GS, Strahm J, Hulburt TC, Beck EC, Waterman BR, Nicholson KF

When pitching a baseball, pelvic and trunk pitching kinematics play an integral role in momentum transfer from the lower extremity to the upper extremity. However, it is unknown how hip and trunk ROM and hip shoulder separation interplay with pelvic and trunk pitching kinematics. The purpose of this study was to determine the relationship between clinical trunk and hip range of motion (ROM) and pitching biomechanical pelvis and trunk kinematics, and kinematic sequencing. High school pitchers were assessed for trunk rotation via motion capture and hip ROM via a goniometer prior to pitching. Trunk rotation was designated as dominant and non-dominant sides, and hips as stance and lead limbs. Pitchers threw four fastballs during three dimensional biomechanical assessment. Spearman’s Rho correlations were performed between trunk and hip ROM, and trunk and hip biomechanical kinematics, and kinematic pitching sequence. Thirty-two pitchers (mean age: 16.3 + 1.2 years, height = 184.0 + 6.9 cm, mass = 76.8 + 20.8 kg) were included in this study. Their mean pitch velocity was 34.7 + 2.3 m/s, peak pelvis rotation velocity: 669.1 + 95.5 deg/s, and peak trunk rotation velocity: 1084.7 + 93.0 deg/s. There were no differences between dominant and non-dominant side trunk rotation, or between stance and lead hip ROM. There were no significant relationships between trunk or hip ROM and pitching kinematics. There was a significant relationship between hip shoulder separation and peak trunk rotation velocity (r = 0.390, p=0.027). There was a significant relationship between pitch velocity and peak trunk rotation velocity (r = 0.478, p = 0.006). There were no other significant relationships between pitching kinematics or kinematic sequencing.  The authors found that hip and shoulder separation is related to trunk rotation velocity, and ultimately pitch velocity. These ROM measurements can be used as normative values for hip shoulder separation in high school pitchers.

Abstract  |  IJSPT-15_6-28-Bullock

Influence of Limb Dominance and Shoulder Injury on Strength and Explosive Force in US Marines.
Authors: Poploski KM, Picha KJ, Winters JD, Royer SD, Heebner NR, Lambert B, Lephart SM, Abt JP

The specialized roles of many military personnel require specific skills and high physical demands, placing unique stresses on the shoulders and increasing risk of injury. As normal dominant/nondominant shoulder asymmetries have been established in military personnel, bilateral strength comparisons must be understood in context of daily physical demands to monitor patients’ progress or readiness to return to duty. This study aims to assess bilateral differences in strength and explosive force in United States Marines with a history of dominant or nondominant shoulder pathology. A total of 52 full-duty, male US Marines with a shoulder injury within the prior year participated. Bilateral isokinetic shoulder internal (IR) and external (ER) rotation strength, and peak force (Peak Force) and average rate of force production (Avg Rate) during an explosive push-up were collected. Dominant versus nondominant side data were independently examined within each group (DOM: dominant injury, NOND: nondominant injury). Comparison between DOM and NOND, as well as previously published CON (no history of shoulder injury) was also completed. NOND (n = 26) demonstrated significantly less IR (p < 0.001) and ER (p = 0.003) strength and Peak Force (p = 0.001) and Avg Rate (p = 0.047) on the injured side, while DOM (n = 26) demonstrated no bilateral differences in strength or push-up performance. Comparison between the three groups showed that NOND demonstrated significantly less ER strength than CON (p = 0.022). Military personnel demonstrate asymmetric strength patterns likely due to increased demand of the dominant shoulder. US Marines with a history of injury to the nondominant shoulder performed differently than those with a dominant side injury, presenting with both strength and push-up asymmetries. They also demonstrated significant ER strength deficits compared to CON. Common clinical practice and previous literature often compare injured and uninjured limbs or injured individuals to healthy controls, but further distinction of dominant or nondominant side may provide more accurate information needed to develop targeted treatment strategies. Recognizing unique occupational demands and how patients may present differently with dominant versus nondominant side shoulder injuries are important considerations for ensuring accurate assessment and effective individualized rehabilitation.

Abstract  |  IJSPT-15_6-29-Poploski

CASE SERIES / REPORTS
Use of an Upper Extremity Functional Testing Algorithm to Determine Return to Play Readiness in Collegiate Football Players: A Case Series.
Authors: Pontillo M, Sennett BJ, Bellm E

Return to play decision making for upper extremity injuries is challenging due to a lack of evidence-based protocols and testing. Current guidelines utilize tests and measures with minimal evidence on re-injury risks and prediction. The purpose of this case series is to highlight a functional testing algorithm for upper extremities injuries and the outcomes for the patients that followed it.  Six subjects (18-21 years old) who underwent shoulder capsulolabral repair secondary to recurrent instability and/or unyielding pain were included. All subjects underwent a criterion-based rehabilitation program before being assessed with the authors’ upper extremity functional testing algorithm. The upper extremity functional testing algorithm consists of measures of active range of motion (AROM), passive range of motion (PROM), peak isometric force, a fatigue battery testing, and the closed kinetic chain upper extremity stability test (CKCUEST) to assess readiness for return to sport. All athletes achieved > 90% symmetry on at least two out of three tests during a fatigue testing protocol and at least 25 touches on the CKCUEST. All of the athletes returned to unrestricted football the season following surgical intervention. None of the athletes sustained an additional glenohumeral subluxation, dislocation, or upper extremity injury requiring surgical intervention for the remainder of their athletic careers (six years). The presented cases help to illustrate the effectiveness of the upper extremity functional testing algorithm to assess return to sport readiness for male collegiate football athletes. The algorithm included testing of AROM/PROM and strength that is typically used, but also included the CKCUEST and fatigue testing to further challenge and assess the upper extremity prior to returning to sports.

Abstract  |  IJSPT-15_6-30-Pontillo

Criterion-Based Rehabilitation Program with Return to Sport Testing Following ACL Reconstruction: A Case Series.
Authors: Joreitz R, Lynch A, Popchak A, Irrgang J

Less than 50% of those sustaining an anterior cruciate ligament (ACL) injury return to their preinjury level of sports participation or participate in competitive sport at two to seven years post ACL reconstruction (ACLR). After ACLR, it has been reported that frequency of subsequent ACL tears has reached as high as 31%. The purpose of this case series was to evaluate return to sport and reinjury rates following the use of a criterion-based rehabilitation protocol with a final return to sport test that utilizes minimal equipment following ACL reconstruction. Following ACL reconstruction, participants were included if they had a goal of returning to their pre-injury sport or level of activity, were between 16 and 50 years of age at the time of evaluation, had at least 25 physical therapy visits covered by insurance, and planned to complete physical therapy until clearance for return to sport. Forty-three participants met the inclusion criteria and enrolled in the study. Twenty-one participants completed the full course of rehabilitation including passing their return to sport test and nineteen participants completed the two-year follow-up. Data obtained at two years indicated that 84% were able to return to their preinjury level of sports competition. A smaller percentage (16%) were able to return to a reduced level of sport and only one participant reported a second ACL injury. Participants that completed the full course of rehabilitation and passed return to sport testing had a larger percentage that were able to return to preinjury participation levels than currently reported in the literature. This case series did not exclude participants based on graft type, single vs double bundle procedure, ACL revision surgeries, nor concomitant procedures or injuries.

Abstract  |  IJSPT-15_6-31-Joreitz

Hip and Pelvic Stability and Gait Retraining in the Management of Athletic Pubalgia and Hip Labral Pathology in a Female Runner: A Case Report.
Authors: Moran MW, Rogowski KR

Athletic pubalgia is a prevalent injury in athletes who kick, pivot, and cut, however it is poorly described in the literature. Many athletes with this diagnosis fail conservative management secondary to continued pain with activity and require surgical intervention for return to sport. The purpose of this case report is to describe an intervention strategy focusing on gait retraining and hip and lumbopelvic stability for a female runner diagnosed with athletic pubalgia and a labral tear of the hip. This case report involved a 45-year-old female runner who was seen for 14 visits, from examination to return to sport, with a follow up at 12 months post discharge. Interventions included hip, pelvic, and lumbar stability exercises, and gait retraining. Outcomes measurements included: pain on the numeric pain rating scale, the Lower Extremity Functional Scale (LEFS), gait mechanics, strength, and participation in sport. At discharge the subject demonstrated improved strength of all muscle groups and changes in lower extremity running biomechanics. Changes in running mechanics included increased cadence, decreased pelvic drop, diminished over striding, and improved knee control with less valgus movement during stance phase of gait. The subject reported no pain with running or recreational activities at discharge and follow up at 12 months post discharge.  Most of the literature on conservative rehabilitation for athletic pubalgia focuses on athletes whose sports require pivoting and kicking. The literature provides little information on gait analysis and retraining for runners with a diagnosis of athletic pubalgia and/or hip labrum tears. The program used in this case report including gait retraining and hip, pelvic, and lumbar stability training allowed for full return to running in a 45-year-old female with a diagnosis of hip labrum tear and athletic pubalgia. Further research is needed to discern best conservative treatment for runners with athletic pubalgia and/or hip labral tears.

Abstract  |  IJSPT-15_6-32-Moran

In-Season Rehabilitation Program using Blood Flow Restriction Therapy for Two Decathletes with Patellar Tendinopathy: A Case Report.
Authors: Cuddeford T, Brumitt J

Patellar tendinopathy is an overuse injury experienced primarily by athletes; especially athletes who participate in sports that involve frequent jumping. Therapeutic exercise is the primary conservative treatment for patients with this condition. However, some patients with patellar tendinopathy may be unable to tolerate the loading that occurs during exercise. The use of blood flow restriction (BFR) therapy for patients with patellar tendinopathy may allow the athlete to exercise with a lower load while still experiencing the physiological benefits associated with training at a higher intensity. The purpose of this case report was to detail the outcomes from a rehabilitation program utilizing BFR for two collegiate decathletes with patellar tendinopathy. Two NCAA Division III freshmen collegiate decathletes with a history of left knee pain prior to college and had been complaining of increasing pain during the initial month of track practices. Findings from the musculoskeletal examinations included left sided lower extremity weakness, pain during functional testing, pain when palpating the left patellar tendon, and VISA-P scores less than 80. Ultrasound imaging at baseline revealed thickened tendons on the left with hypoechoic regions.  Both athletes participated in 20 therapy sessions consisting of therapeutic exercises performed with BFR. Both athletes experienced improvements in pain scores, increases in lower extremity strength, improved functional test performance, higher VISA-P scores, and improvements in tendon size and appearance as measured by diagnostic ultrasound. Both athletes experienced improvements with the BFR-based therapeutic exercise program and were able to compete throughout the track season. The use of BFR may allow patients who are unable to tolerate exercise due to a pain an alternative approach during rehabilitation. Future research should compare therapeutic exercise programs for this condition with and without BFR.

Abstract  |  IJSPT-15_6-33-Cuddeford

Consideration of Sport Demands for an 18-year-old Lacrosse Player With Recalcitrant Symptomatic Spondylolysis: A Case Report.
Authors: Murray MK, Maxwell J

Spondylolysis is an anatomical defect or fracture of the pars interarticularis and encompasses almost half of all cases of low back pain in adolescent athletes. Most athletes return to sport with conservative treatment, but it is possible that consideration of sport demands may further improve rate of successful return. When surgery is performed, complication rate is high, so all conservative measures should be explored before considering surgical intervention. The purpose of this case report is to present a program where demands of sport were considered and allowed successful return to sport for a subject with recalcitrant symptomatic spondylolysis that had failed to respond to prior treatment. The subject was an 18-year-old lacrosse player with a history of recalcitrant symptomatic spondylolysis that failed three courses of conservative treatment and had been unsuccessful in returning to sport. A multi-phase program with a focus on multi-planar and full kinetic chain activities that addressed the nature of the sport demands is described, along with improvements in pain level, strength, range of motion, and subjective outcome scores. The subject was able to successfully return to sport after 10 weeks of physical therapy and complete the remaining few months of his lacrosse season without reinjury. Range of motion and strength testing was markedly improved upon discharge. The subject’s Modified Oswestry Disability Index improved from 16% to 0% and his pain level did not rise above 2/10 with any sport activity upon return. Although return to sport rates following spondylolysis in young athletes is high, this case report demonstrates that a consideration of sport demands may increase return to sport rates in athletes that do not respond to standard care and prevent surgical intervention.

Abstract  |  IJSPT-15_6-34-Murray

The Non-operative Rehabilitation of a Traumatic Complete Ulnar Collateral Ligament Tear of the Elbow in a High School Wrestler: A Case Report.
Authors: Stahl RA, Eckenrode BJ

Injuries frequently occur in competitive wrestling, with the elbow joint representing about 25% of all injuries. Specific to the elbow, the ulnar collateral ligament (UCL) can be injured traumatically from takedowns in wrestling. In athletes with complete UCL tears, surgical management is often recommended with nonoperative management resulting in less favorable outcomes. The purpose of this case report is to present a nonoperative criterion-based rehabilitation program for a high school wrestler with a complete UCL tear of the elbow. A 17-year-old male wrestler presented to physical therapy with a complete UCL tear sustained from falling on an outstretched hand during a wrestling match. He presented with limited elbow range of motion (ROM), medial elbow instability, and weakness of the involved shoulder and forearm musculature. A three staged criterion-based rehabilitation protocol was developed for this subject based on specific criteria, including pain, elbow ROM, arm strength, and functional outcomes. The subject was treated for nine visits over six weeks, and demonstrated improvements in all strength tests of the involved upper extremity, with elbow flexion strength improving the most by 58%. Return to sport tests were used to assess the subject’s ability to return to practice. At approximately eight weeks after initial injury, the subject was able to return to full participation in competitive wrestling with no reports of elbow pain or instability. Through the utilization of a criterion-based rehabilitation protocol for the nonoperative management of an UCL injury, this high school wrestler was able to safely progress back to wrestling without pain or instability in an accelerated time frame. Previously, no detailed rehabilitation guidelines for nonoperative management of UCL injuries in contact sports have been described. Additionally, few studies exist which report on the inclusion of RTS testing following an injury to the UCL of the elbow, as RTS testing is optimal for determining readiness for sport.

Abstract  |  IJSPT-15_6-35-Stahl

CLINICAL COMMENTARY
Gluteal Inhibition After Hip Arthroscopy: A Role for Neuromuscular Electrical Stimulation.
Authors: Mumbleau AM, Schilaty ND, Hewett TE

The number of hip arthroscopies (HAs) performed in the United States is increasing exponentially. Previous authors have shown improvements in short- and mid-term functional outcomes after HA. Despite established overall improvements, functional and objective impairments may persist. In particular, preliminary work demonstrates differences in hip strength between patients who undergo HA when compared to healthy controls at 12- and 24-months post-operative. The purpose of this clinical commentary is to highlight the persistent hip muscle strength and neuromuscular deficits that occur after HA, as well as propose the utilization of neuromuscular electrical stimulation (NMES) as an adjunct to strengthening exercises in early post-operative rehabilitation to address deficits.

Abstract  |  IJSPT-15_6-36-Mumbleau

The Gap Between Research and Clinical Practice for Injury Prevention in Elite Sport: A Clinical Commentary.
Authors: Short S, Tuttle M

As clinicians strive to apply evidence-based principles, team-based practitioners have identified a large gap as it relates to published research, ideal applications of evidence-based practice, and actual clinical practice related to injury prevention in elite sport within the United States. For rehabilitation professionals, especially those intimately involved in the research of injury prevention, the solution often seems quite clear and defined. However, preventing injury by implementing the latest recommendation from the most recent prospective study on the using the FIFA 11+ warm-up, a Copenhagen Adduction exercise, or a plyometric drill with elite athletes may not be as effective as was seen among the cohort used in the study. In addition to extrapolating research, clinicians face additional challenges such as variance among professions, schedule density, and off-season contacts with athletes. There is an inherent difficulty in the application of research to practice in elite sport as it relies on the teamwork of not only the practitioner and athlete, but the entire sporting organizational structure and those involved in athlete participation. The purpose of this clinical commentary is to explore the difficulty with application of research in clinical practice and to discuss potential strategies for improving carry over from research to clinical practice.

Abstract  |  IJSPT-15_6-37-Short