Screening on Collect Students: Postural Risk Factors of Spinal Musculoskeletal Problems and Scoliosis

Background: Overuse of electronic products and decrease in levels of physical activity may lead to an increased incidence of spinal health problems in college students. This study aims to 1) identify the incidence of spinal health problems in college students, 2) to explore the key postural factors in development of spinal musculoskeletal dysfunction and scoliosis, and 3) to clarify new strategies for early identication and prevention of scoliosis. Methods: A cross-sectional screening by static posture assessment, selective functional movement assessment (SFMA) and Adam's Forward Bend Test, was conducted to 306 college students from October to December 2019. Descriptive analysis, Spearman correlation analysis and binomial logistic regression analysis were performed on the collected data. Results: Static postural assessment was completed among 306 college students, 53% of students’ external auditory meatus and acromioclavicular joint were not in the same gravitational line, 45% had forward-head posture, 42% had uneven shoulders. When performing SFMA, we found spinal musculoskeletal dysfunctions, including abnormalities of multi-segment spine exion (32%), cervical rotation to right (18%), cervical rotation to left (16%), etc. In Adam's Forward Bend Test, 10.78% had a positive result, which suggested structural or functional scoliosis. Correlation analysis showed that the top three postural factors related to spinal musculoskeletal dysfunctions included uneven shoulders, forward-head, position of thorax and pelvis rotated. And top three postural factors related to scoliosis were spinous processes line deviating from midline, winged scapula and head rotation off midline. Logistic regression analysis displayed that there are two high risk factors for scoliosis, including external auditory meatus and acromioclavicular joint not in the same vertical line (OR = 6.314), and deviation of spinous processes line (OR = 12.743). Conclusions: Poor posture, spinal musculoskeletal dysfunction and scoliosis affect a signicant proportion of college students. While their spinal musculoskeletal dysfunction and are closely related to poor posture.


Background
Wireless network has been available in wide areas in this world [1]. As an important tool for education, most educational institutes in China provide network services to students [2]. At the meantime, increase numbers of students have smart phones or personal digital devices [3].
Overuse of smart phone or personal digital device will induce decreasing of physical or outdoor activities [4]. Reading message from electronic products required students maintain their posture in an unnatural way, such as sitting with round back, forward head, or crossed legs (one leg on top of the other) for a long period of time. The lack of movement and prolonged unnatural position contribute to the increased occurrence of poor posture and spinal deformities [5]. College students are among the worst group of users in reading messages from smart phones or personal digital devices for longer time with poor posture [6,7].
It was reported that prolonged time in poor posture is associated with asymmetric load [8] and further deteriorates muscular balance [9,10]. While spinal muscular unbalance for a long period of time may cause a visible curvature in the spine, which can be reversible in most of cases by rehabilitation therapy [11]. If the curvature is not detected and corrected at this phase, the unbalanced force loading on to the spine will cause deformation of the spine and may eventually cause structural scoliosis. In patients with structural scoliosis, the spinous processes tend to be concave and varying degrees of rotation may also occur in the ribs and joints [12]. In other words, prolonged time in keeping the body in a poor posture will induce paravertebral muscle pain, unbalanced force application to the vertebral bone, and even worse, permanent spinal malformation, including scoliosis.
To prevent developmental spine problems in adolescence, many educators promoted physical activity in schools [13]; they developed guideline for restricting hours of smart phone usage [14]. Healthcare staff carried out screens on students with a goal to identify reversible spinal curves and give them appropriate treatments in the early phase [15]. However, few previous reports examined the causal relationship between poor posture and the occurrence of spinal musculoskeletal damages even scoliosis. What's more, we do not know key risk factors caused by poor postures that contribute to the development of scoliosis.
We aimed to nd answers to these questions, speci cally, through a cross-sectional screening by static posture assessment, selective functional movement assessment (SFMA) and Adam's Forward Bend Test, we tried to clarify the epidemiology of body posture, spinal musculoskeletal dysfunction and scoliosis in college students, then to explore posture-related factors in development of musculoskeletal damage and scoliosis to provide key indicators for monitoring and prevention strategies, and look for treatment strategies for college students' spinal damages through therapeutic guidance of SFMA. Students were freshmen selected by random selection of 9 colleges in Jilin University, a comprehensive university in China, whose students came from all over the country, which can represent the data distribution of Chinese college students.

Screening method
In this study, we used the static posture assessment to determine the abnormality of body posture, used selective functional movement assessment (SFMA) to identify relevant musculoskeletal dysfunction [16] and to assist the diagnosis and treatment of skeletal muscle diseases [17]. And Adam's Forward Bend Test was applied on the screening for scoliosis [18]. Assessment form was attached in the appendix. Dysfunctional non-painful (DN), and Dysfunctional painful (DP) [17] . In this study, in order to assess asymmetries and pathological movements patterns of spine, 5 Top-tier tests including Cervical Patterns ( exion, extension), Cervical Patterns (rotation R+L), Multi-segmental exion, Multi-segmental extension and Multi-segmental rotation, were used to screen for spinal musculoskeletal dysfunction of college students.
Adam's Forward Bend Test The subjects stood with their feet as wide as shoulders, and bent forward as far as possible. Looked for the higher side of the rib cage next to the vertebral column, which was the convex side and suggested Adam's Test was positive. The subjects should be instructed to bend forward, backward, then bend sideward, rotate to the right and left. They also should repeat above Adam's Test to identify individuals with scoliosis.

Statistical analysis
All data were statistically analyzed and plotted using SPSS17.0 (IBM Corporation, Chicago, USA). Descriptive statistics was used for analyzing the percentages of spinal health problems in college students; Spearman correlation analysis was used for reveal relationship of results among three different screening methods; binomial logistic regression analysis was used to analyze the risk factors of scoliosis. p < 0.05 was considered as statistically signi cant.

Results
This study involved 306 college students with an average age of 18.98 ± 0.77 years, including 225 males and 81 females. Their average body mass index (BMI) was 22.21 ± 4.77.

Correlation analysis between SFMA and static postural assessment
As shown in Table 3 (Table 3). The postural factors related to scoliosis were shown in Table 4. The top three related factors were SP line deviating from midline (r = 0.319), winged scapula (r = 0.232), and head rotation off midline (r = 0.193). Besides, scoliosis also related to abnormality of SFMA including cervical rotation to left (r = 0.185), cervical rotation to right (r = 0.183), multisegment extension of spine (r = 0.177), etc.

Binomial logistic regression analysis of Adam's Forward Bend Test
To explore risk factors of posture and spinal musculoskeletal dysfunction contributing to the scoliosis, we performed a binomial logistic regression analysis, where results in Adam's Test (Y, symmetry = 0, asymmetry = 1) were predicted by gender (X 1 , male = 1, female = 2), age (X 2 ), BMI (X 3 ), static posture assessment (X 4 -X 19 , normal = 0, abnormal = 1), SFMA assessment (X 20 -X 27 , FN = 0, FP = 1, DN = 2, DP = 3). Results were displayed in Table 5. People who reported as external auditory meatus and acromioclavicular joint not in the same vertical line were 6.314 times more likely to have scoliosis than those whose external auditory meatus and acromioclavicular joint were in the same vertical line (p < 0.05). And people whose SP line deviated from the midline were 12.743 times more likely to have scoliosis than those whose SP line did not deviate from the midline (p < 0.05).

Discussion
Results in this study showed that poor posture, spinal musculoskeletal dysfunctions and scoliosis were common in college students, which could be considered as three steps of spinal health problems among them. More speci cally, poor posture in college students included external auditory meatus and acromioclavicular joint not in the same gravitational line, forward-head, uneven shoulders, head side bending off midline, round shoulders, protruding abdomen, etc. Spinal musculoskeletal dysfunctions mainly involved abnormalities of multi-segment spine exion, cervical rotation and multi-segment spine extension. Among them, incidence of scoliosis was 10.78% measured by Adam's Test. Khosrovi  By Spearman correlation analysis, we found that key postural factors related to spinal musculoskeletal dysfunction included uneven shoulders, forward-head, position of thorax and pelvis rotated, changes of thoracic kyphosis and head rotation off midline (Table 3). It's reported that musculoskeletal pain among undergraduate students is related to overweight, not having time for leisure, six or more daily hours of mobile phone use [10]. While prolonged sitting and reduced exibility were probably related to incidence of forward head, thoracic kyphosis, and pronated foot [20].
Casas et al. found that neck and back pain of college students is associated with sitting posture with rounded back, feet supported on another chair and crossed legs [21]. Thus, correcting cervical and thoracic postural abnormalities when long hours sitting is the key point for prevention of musculoskeletal dysfunctions.
Postural factors related to scoliosis were spinous processes line deviating from midline, winged scapula and head rotation off midline (Table 4). It's known that trunk balance is maintained by mutual interaction of varieties of factors including visual information, lower limb kinematics, muscle strength of the trunk and limbs and so on [22]. After a long time for deviation of spinous processes line, head and cervical spine play pivotal roles in in uencing global subjacent spinal alignment and pelvic tilt, as compensatory changes occur to maintain horizontal gaze [23]. And head rotation off midline maybe a way of visual compensation for trunk unbalance. Besides, Purnama et al. found winging scapula was identi ed in all athlete's table tennis and tennis with scoliosis because of muscle imbalance in the kinetic link of the upper body [24]. It's also reported that main compensatory mechanisms of scoliosis patients adopt to maintain an upright posture include decreased sacral slope, increased pelvic tilt, decreased thoracic kyphosis [25]. Once it does decompensate, three-dimensional deformation of spine will be induced or severe. Therefore, early inspection on the spinous processes line, winged scapula and head rotation, should be considered as routine interventions to effectively identify the progress of scoliosis in college students.
By binomial logistic regression analysis, external auditory meatus and acromioclavicular joint not in the same gravitational line was shown as one of the high risk factors for scoliosis in this study (Table 5). External auditory meatus and acromioclavicular joint not in the same gravitational line usually means rotation or forward displacement of the head on the cervical spine [26]. In this study, 14% of college students appeared head rotation, and 45% had forward-head posture. The latter can be considered as the main cause of external auditory meatus and acromioclavicular joint not in the same vertical line. Forward-head posture is characterized by hyperextension of the upper cervical spine and exion of the lower cervical spine, which is associated with shortening of the upper trapezius, posterior cervical extensor muscles, sternocleidomastoid, and levator scapulae muscles [27]. With the increase of compressive forces caused by forward-head on the cervical apophyseal joints and posterior part of the vertebra and changes in connective tissue length and strength, cervical lordosis and thoracic kyphosis values will be signi cantly affected [28]. Maybe this is the hidden mechanism of scoliosis induced by forward head posture.
Spinous processes (SP) line deviating from the midline was suggested as another high risk factor for scoliosis. SP line is usually used as a low-cost, easy to use, radiation free method during family screening for scoliosis. It's also reported that it is important to monitor the spine trunk deviation when a person is standing straight, because it can indicate whether or not the subject has orthopathology [29]. Thus, external auditory meatus and acromioclavicular joint not in the same vertical line and deviation of SP line can be considered as important indicators for monitoring and prevention strategies of scoliosis.
Furthermore, the SFMA is a standardized movement assessment tool intended to provide a systematic process to identify the best possible therapeutic and corrective treatment program for patients. In our study, we analyzed correlation among SFMA, posture assessment and scoliosis (Table 3). Result showed that rounded-shoulder was related to limitation of active cervical rotation. Rounded-shoulder posture is characterized by a protracted, downwardly rotated, and anteriorly tipped scapula position with increased cervical lordosis and upper thoracic kyphosis [30]. Rounded-shoulder was results from loss of lower trapezius and serratus anterior activity, tightness in the pectoralis minor, which can easily cause the overuse of the upper trapezius muscle, which affects the contralateral rotation of the cervical spine. Thus, using SFMA, we can nd abnormality of cervical rotation of college students with rounded-shoulders. Physical therapist can treat cervical rotation related muscles to correct the round shoulder posture. It has been proved that the posterior tilting exercise after pectoralis minor stretching is the most effective method for eliciting greater lower trapezius and serratus anterior muscle activation [31]. Due to the tight connection between scoliosis and abnormalities of cervical rotation and multi-segment spine extension (Table 4), correcting these abnormalities may help reduce the chance of scoliosis.

Conclusions
College students are high-risk groups with spinal health problems. Our studies have con rmed that college students' spine musculoskeletal dysfunction and scoliosis are closely related to poor posture. There are two signi cant risk factors for scoliosis, including external auditory meatus and acromioclavicular joint not in the same vertical line and deviation of spinous processes line. They can be applied on early recognition and prevention of scoliosis. Additionally, SFMA can be used in clinical practice to evaluate the spine musculoskeletal dysfunction, and to guide targeted treatments to correct poor posture and scoliosis.
Abbreviations SFMA: Selective functional movement assessment