|Year : 2022 | Volume
| Issue : 3 | Page : 325-329
Correlation of resting scapular position and functional throwing performance index among amateur basketball players: An observational study
Reema Joshi, Varun Pohekar
Department of Physiotherapy, Dr. D Y Patil College of Physiotherapy, Dr. DY Patil Vidyapeeth(Deemed to be University), Pimpri-Chinchwad, Pune-411018, Maharashtra, India
|Date of Submission||22-Apr-2022|
|Date of Acceptance||01-Aug-2022|
|Date of Web Publication||29-Sep-2022|
Dr. Reema Joshi
Department of Physiotherapy, Dr. D Y Patil College of Physiotherapy, Dr. DY Patil Vidyapeeth(Deemed to be University), Pimpri-Chinchwad, Pune 411018, Maharashtra
Source of Support: None, Conflict of Interest: None
Background: Scapular dyskinesis is prevalent in 54.5% of overhead athletes. Scapular dyskinesis is abnormal positioning of the scapula over the thorax and also abnormal motions of the scapula. Any alterations to the normal scapular position may alter the accuracy of striking and serving in basketball players. This study aims to find out the relation between the resting scapular position and the throwing accuracy of players. Results: The research suggests that there is a moderate correlation present between the resting scapular position and the throwing accuracy of the players. Conclusion: In this study, results state that the resting position of the scapula plays an important role in power generation and biomechanics of throwing in overhead athletes affecting the throwing accuracy of players.
Keywords: Functional throwing performance index, overhead athletes, overhead injuries, resting capular position, throwing accuracy
|How to cite this article:|
Joshi R, Pohekar V. Correlation of resting scapular position and functional throwing performance index among amateur basketball players: An observational study. MGM J Med Sci 2022;9:325-9
|How to cite this URL:|
Joshi R, Pohekar V. Correlation of resting scapular position and functional throwing performance index among amateur basketball players: An observational study. MGM J Med Sci [serial online] 2022 [cited 2023 Feb 6];9:325-9. Available from: http://www.mgmjms.com/text.asp?2022/9/3/325/357473
| Introduction|| |
Basketball is a sport that requires very high composite actions and very complex coordination of upper and lower body movements. Scapular and shoulder muscles are very crucial for shooting, dribbling, and defensive works like grabbing rebounds and blocking, coupled motion between the scapula and humerus, known as scapula-humeral rhythm is necessary for efficient movement of the arm and maintains the stability of the joint. For throwing the ball through the hoop, the player needs to go through complex movements which include jumps, trunk rotations, and shoulder movements. The overhead throwing action is a very complex dynamic activity involving the whole body.
The normal resting position of the scapula is approximately horizontal, with 35o of internal rotation, and 10o anterior tilt. The scapula is important to provide a stable base during shoulder movement. If the scapula fails to maintain this, it can cause inefficient shoulder function and poor performance. In basketball players, especially for the throwing mechanics, coupled scapular retraction is a very important aspect. A good performance of the kinetic chain requires adequate anatomy and physiology of the joint. The altered position and motion of the scapula may create a loss of control of rotation thus resulting in excessive internal rotation. Problems that will occur in the functioning of the joint will include external impingement, susceptibility to decreased rotator cuff strength, and increased anterior capsular strain.
Overhead throwing activity requires a repetitive high velocity, high load, and large range of motion. So it is important to assess for resting scapular position of the player, during the screening process as it may affect the performance of the player. Thus the study intends to find out the resting scapular position and throwing accuracy in Amateur university players.
| Materials and methods|| |
50 young recreational university basketball players between 18–30 years playing since 6 months those were having any acute recent shoulder injury, any history of recent upper extremity surgery, history of fracture in recent months, and any cardio-respiratory issue or history were excluded from the study. All the participants were informed about the procedure of the study and written informed consent was taken before the study.
Resting scapular position: The participant was made to sit comfortably on a stool with the back straight and hands on the lap. Markings were made after palpation for the medial angle of the scapula and inferior angle of the scapula with a marker and the corresponding vertebrae i.e. T3 and T7 vertebrae. Linear measurement was taken between the angles and corresponding vertebrae. The distance was noted down.
To measure the muscle strength of the Upper Trapezius, the subject was made to sit on a chair and told to shrug his shoulder. Stabilization was given by placing the opposite hand underside of the chair. Resistance was given on top of the acromion process. For Serratus Anterior, the patient was told to lie down in a supine position and hold his extremity in 90o of shoulder flexion, scapular retraction, elbow extension, and palm facing up. Resistance was applied over the proximal palm so the force was directed vertically through the forearm. For the Middle trapezius and Lower trapezius, the subject will lie down in a prone position, and resistance will be given 5 cm proximal to the radial styloid process. For the middle trapezius, the subject will be asked to hold the arm in 90o of shoulder abduction with the scapula retracted and the arm externally rotated so that the thumb is pointing upwards. And for the Lower trapezius, the subject will hold the arm in approximately 160o of abduction with external rotation and scapular retraction.
Functional Throwing Performance Index (FTPI): To measure the throwing accuracy of the participant, the test was used. A tape was placed 15ft (4.6m) from a wall. A square of 1ft by 1ft (0.3m by 0.3m) was placed 4ft (1.2 m) above the floor on the wall. The subject was given some warmup throws. Then timer was started for the 30s to perform as many accurate throws as possible for him/her into the target box. Every participant was made to perform three attempts and the mean was calculated for statistical analysis.
| Results|| |
All statistical analysis was done using the statistical software MedCalc 18.2.1, and the level of significance was set at P < 0.05. Descriptive statistics were performed to assess the mean and standard deviation accordingly. Interferential statistics were done using the Spearman Correlation test.
Out of the total of 50 participants, 12 participants were found with a discrepancy in scapular resting position. Subjects with scapular discrepancy had 37.3% average throwing accuracy and subjects without scapular discrepancy had shown 56.4% throwing accuracy [Figure 1]. The Mean Resting Scapular Position at the level of the spine of the scapula of the Dominant side was 7.56 ± 0.92 cm and the Mean Resting Scapular Position at the level of the inferior angle of the scapula of the Dominant side was 9.67 ± 1.40 cm [Table 1].
|Figure 1: Distribution of subjects of scapular discrepancy with functional throwing performance Index (FTPI)|
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|Table 1: Comparison of scapular resting position in amateur basketball players between dominant and non-dominant sides|
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According to COLTON’S Guidelines for Evaluating Correlation Coefficients, the correlation between MMT and throwing accuracy (FTPI%) of upper trapezius (rs=0.609), middle trapezius (rs=0.568), lower trapezius (rs=0.467) and serratus anterior (rs=0.584) [Table 2] shows a good degree of relationship with lower trapezius shows a fair degree of relationship.
|Table 2: Relationship between Muscular strength Using MMT and throwing Accuracy|
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In the comparison of the relationship of Resting Scapular Position and Functional throwing performance index (FTPI%) with Spearman’s coefficient of rank correlation (rho) value of 0.554 with 0.326 to 0.721 of 95% Confidence Interval for rho P < 0.001. The value of 0.554 shows that there is a strong correlation between Discrepancy and FTPI%.
| Discussion|| |
In this study, 50 participants were included after screening for the inclusion and exclusion criteria. Out of the 50 players, 12 were found to have scapular discrepancies[Figure 1]. Scapular dyskinesis is the abnormal positioning of the scapula over the thorax and abnormal scapular motions which may occur due to fatigue, inhibition by intra-articular glenohumeral or sub-acromial processes (eg, subacromial impingement), or due to neurologic dysfunction (Long thoracic nerve injury)., Scapular discrepancy can be due to bony causes, previous fractures, or postural changes. Neurological causes can be nerve palsy or cervical radiculopathy. Soft tissue factors contributing to scapular dyskinesis include muscle tightness or intrinsic muscle problems and changes in peri-scapular muscle activations. Weakness of scapulothoracic muscles strongly leads to abnormal positioning of scapula, disturbed scapulohumeral rhythm, and shoulder complex dysfunction.
Dyskinesis shows an alteration of static scapular position or dynamic motion of the scapula in coordination with the motion of the arm. The change in the position or motion results in loss of control of retraction and posterior tilt, resulting in protraction, anterior tilt, and increased internal rotation. Problems during movement include external impingement due to anterior tilt, internal impingement due to internal rotation and glenoid ante tilting, decreased strength of the rotator cuff, and an increase in a strain of the anterior capsule in the shoulder. Players might have chronic shoulder pain due to sport-specific alterations, changes in strength, flexibility, and posture in the shoulder joint but along with alterations in kinetic chain links. These changes in biomechanics and movement strategies often lead to overload injuries in the shoulder joint.
Kibler et al. studied that the scapula forms a base from where the rotator cuff originates. He also said that the scapula has a major role in stabilizing the glenohumeral articulation, as a base for muscles origin and insertion, and as a major link in the kinetic chain in delivering energy and force from the trunk and legs to the hand. The present study has also shown the weakness of the scapular muscle.
According to Suzuki et al., accuracy is a product of a coordinated and sequentially activated kinetic chain system. The kinetic chain breakage is suggested by Kibler and Lintner et al. to be the outcome of repetitive, vigorous activities in young and old athletes. The effectiveness of the kinetic chain is dependent on 3 factors: (1) optimized anatomy of all segments; (2) muscle flexibility and strength, task-specific motor patterns for muscle activation and (3) mechanism for the generation of forces distributed across shoulder joint motions that result into desired athletic activity. Several functions of the kinetic chain include: (1) using integrated programs of muscle activation to temporarily link multiple body segments into one functional segment; (2) giving a stable proximal base for distal arm mobility; (3) maximizing force development in large muscles of the core and transferring it to hand; (4) generating interactive movements at distal joints that develop more force and energy; and (5) generating torques that decrease deceleration forces. This study suggests that the scapular muscle weakness might causes discrepancy in resting scapular position which will disturb the shoulder biomechanics and disturbs the coupled motion which might cause poor functional throwing accuracy.
Throwing overhead activity includes various phases in which various musculatures work simultaneously. The shoulder girdle muscle (levator scapulae, serratus anterior, rhomboids, and pectoralis minor) is important during these phases. The muscles co-coordinately work together to stabilize the scapula and proper positioning of the glenoid cavity for the subsequent action of the head of the humerus. If there is dysfunction of these scapular muscles, it may result in additional stress on anterior shoulder stabilizers. Dysfunction or weakness of muscles acting on the scapula may contribute to an increase in changes in scapular position, resulting in a change in position of other proximal and distal joints. The serratus anterior, upper, middle, and lower trapezius, rhomboids, and levator scapulae are responsible for regulating the rotation of the scapula. The upper and lower trapezius unites with the upper and lower portions of the serratus anterior to bring out an upward rotation force of the scapula.,
Since the proper glenohumeral joint positioning and adequate muscle performance both are dependent on the position of the scapula, it is important to study the role of the scapula in the throwing mechanism. Stability is achieved by scapula stabilizers which provide adequate functional support during throwing. The scapular muscles must contract constantly during all phases of throwing to achieve efficient working of muscles. If there is a strength imbalance around the scapula-thoracic joint, inadequate force production in throwing motion may occur. Research has shown that muscle groups with inefficient length-tension relationships interfere with optimal firing patterns during contraction of the muscle which can affect the throwing performance and increase the risk of injury.
The upper and lower trapezius, rhomboids, and serratus anterior work together concentrically during the initial phases of throwing to fix the scapula in the elevated and retracted position. If the scapula is not fully retracted during these stages, there may be energy loss in the storage of glenohumeral muscles which include pectoralis major and external rotators. This loss can prevent adequate force production in the acceleration phase of throwing because the arm is placed more anteriorly initially. Throwing mechanics have finally altered and a decrease in performance or increase in the risk of glenohumeral injury results.,
Our research aimed to find out if the resting scapular position has any role to play in the throwing mechanism. This was done for the Amateur players because they tend to play only 3 or 4 times a week. And if they are intended to upgrade their game and perform for tournaments, they need to be evaluated for proper basketball throwing mechanisms and improvement in physical fitness. Scapular dyskinesis is often underrated in such a screening process, if it is detected at an early stage the performance of the player can be enhanced and the proneness to the injury of the upper extremity can be minimized at a very early stage.
| Conclusion|| |
The study concludes that resting scapular position correlates with the functional throwing performance of basketball players, hence it is necessary to undergo a sports-specific physical assessment before playing any sports as an amateur player to minimize any sports injury.
We thank our institute for providing all support during the study.
Clearance/approval from the Institutional Ethics Committee of Dr. D Y Patil College of Physiotherapy, Dr. DY Patil Vidyapeeth, (Deemed to be University), Pune-411018, Maharashtra, India was obtained for undertaking the proposed research project on “Correlation of Resting Scapular Position and Functional Throwing Performance Index among Amateur Basketball Players: An Observational Study” vide letter no. DYPCPT/ISEC/74/2021 dated 22 January 2021.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest
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[Table 1], [Table 2]