The Nature of Rehabilitation Programs to Improve Musculoskeletal, Biomechanical, Functional, and Patient-Reported Outcomes in Athletes With ACL Reconstruction: A Scoping Review

Context: After anterior cruciate ligament (ACL) reconstruction (ACLR), athletes commonly undergo prolonged rehabilitation (eg, 9-12 months), but few actually return to preinjury sports activities. The nature (composition, configuration) of an ACL rehabilitation program (ACL-RP) is an important factor in determining rehabilitation outcomes; however, details about the nature of ACL-RPs are reported inconsistently in research studies. To guide future research reporting to support clinical translation and implementation of ACL-RPs, it is necessary to describe the nature, reporting, and outcomes of ACL-RPs in the current literature. Objective: The purpose of this scoping review was to understand the nature and reporting of various ACL-RPs that address musculoskeletal, biomechanical, functional, or patient-reported outcome measures in adult and pediatric athletes with ACLR. Data Sources: Articles were selected from searches in 5 electronic databases (PubMed, EbscoHost [MEDLINE, SportDiscus, CINAHL Plus], PROQuest, Cochrane, and Embase). Study Selection: Studies were included if they evaluated a post-ACL-RP that implemented strength, balance, plyometric, change of direction running, and/or agility running and included self-reported physical function, quality of life, or pain outcomes. Study Design: Scoping review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews (PRISMA-ScR) guidelines. Level of Evidence: Level 4. Data Extraction: Data were extracted and synthesized to evaluate the reporting of acute program variables (APVs) and exercise descriptors (EDs); 17 studies were included in the final synthesis. Results: Studies reported between 0% and 67% of the APVs and EDs combined. Only 2 studies were considered to have adequate reporting of both APVs and EDs. Conclusion: Inadequate reporting of APVs and EDs in past studies restricts the translation and implementation of existing research-based ACL-RPs to present-day clinical contexts.


Term Definition Exercise Interventions
Muscle Strength

Muscle Strength Training
The ability of a muscle to produce force. 11y form of exercise primarily directed at increasing the ability of a muscle or muscle group to produce force. 13

Balance Balance Training
The ability to maintain the body's center of mass and center of pressure within its baseline of support via internal moments countering external moments that act to destabilize the body and its joints. 26y form of exercise primarily directed at increasing the ability to maintain the body's center of-mass and center-of-pressure within its base-ofsupport. 26

Plyometrics Plyometric Training
Movements that include a rapid stretch-shortening cycle and enable a muscle to generate high levels of force in as short a time as possible. 10y form of exercise that includes a rapid stretchshortening cycle and is primarily directed at increasing the ability of a muscle to generate high levels of force in as short a time as possible. 10ange of Direction

Change of Direction Training
The ability to change the velocity and direction of body movement rapidly in pre-planned contexts. 47y form of exercise primarily directed at increasing the ability to change the velocity and direction of body movement rapidly in pre-planned contexts. 47

Agility Training
The ability to change the direction or velocity of body movement rapidly in response to an external stimulus in unplanned contexts and without loss of balance. 8 Any form of exercise primarily directed at increasing the ability to change the direction or velocity of body movement rapidly in response to an external stimulus and without loss of balance. 47Metabolic Training Any form of exercise primarily directed at developing both aerobic and anaerobic energy systems and producing metabolic adaptation in athletes. 19,46

Sports Level
Recreational Individuals with a low level of commitment, little time involvement, and who merely play at the game; dabblers. 16Amateur Individuals are not paid to perform.Individuals are defined by a high level of commitment to excellence coupled with pursuit of activity for pleasure. 16Professional Individuals are paid to perform.Individuals are defined by being the most specialized and highly trained coupled with pursuit of activity for employment. 16   This study demonstrated that progressive eccentric resistance exercise implemented three weeks after reconstruction of the anterior cruciate ligament can induce changes in the structure of the quadriceps and gluteus maximus that greatly exceed (by more than twofold) those changes following an institutional standard rehabilitation program.These structural increases were observed in both the involved and the uninvolved thighs and with both the semitendinosus-gracilis and the bone-patellar tendon-bone grafts.

Figure A1 :
Figure A1: Timeline of the included studies based on publication year.

Figure A2 :
Figure A2: Total Reporting Frequencies of APVs and EDs Combined Per Study

Table A3 :
Acute Program Variables and Exercise Descriptors

:
Reporting Frequency of Acute Program Variables by Exercise Type.Frequency is calculated by the number of acute program variables reported out of the total possible number of acute program variables that could have been reported across all studies analyzed in this scoping review for each exercise type.
Figure A3: Reporting Frequencies of APVs and EDs Figure A4: Reporting Frequency of Acute Program Variables.Frequency is calculated by the number of acute program variables reported out of the total possible number of acute program variables that could have been reported across all studies analyzed in this scoping review.

:
Reporting Frequency of Exercise Descriptors by Exercise Type.Frequency is calculated by the number of exercise descriptors reported out of the total possible number of exercise descriptors that could have been reported across all studies analyzed in this scoping review.
% of ED reported out of total number of exercises Single-or double-leg exercise loading method total duration of program unsupervised/supervised progression Figure A7: Reporting Frequency of Exercise Descriptors by Exercise Type.Frequency is calculated by the number of exercise descriptors reported out of the total possible number of exercise descriptors that could have been reported across all studies analyzed in this scoping review for each exercise type.