Prevalence of shoulder pain amongst Malaysia men's wheelchair basketball players: A cross-sectional study

Mohd Fakhrulsani Abdul Hamid; Mohamad Shariff A. Hamid

doi:10.4103/mohe.mohe_31_22

ORIGINAL ARTICLE

Year : 2022 | Volume : 11 | Issue : 2 | Page : 97-107

Prevalence of shoulder pain amongst Malaysia men's wheelchair basketball players: A cross-sectional study

Mohd Fakhrulsani Abdul Hamid¹, Mohamad Shariff A. Hamid²
¹ Department of Orthopaedic and Traumatology, Orthopaedic Clinic, Hospital Sultanah Bahiyah, Kedah Darul Aman, Malaysia
² Sports Medicine Unit, Faculty of Medicine University of Malaya; National Sports Medicine Centre, National Sports Institute, Kuala Lumpur, Federal Territory of Kuala Lumpur, Malaysia

Date of Submission	02-Nov-2022
Date of Decision	29-Dec-2022
Date of Acceptance	31-Dec-2022
Date of Web Publication	22-Feb-2023

Correspondence Address:
Mohamad Shariff A. Hamid
Sports Medicine Unit, Faculty of Medicine University of Malaya; National Sports Medicine Centre, National Sports Institute, Kuala Lumpur, Federal Territory of Kuala Lumpur
Malaysia

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/mohe.mohe_31_22

Abstract

Introduction: The shoulder is at high risk of injury, particularly in throwing activities such as basketball.
]Aims: The objective of this study was to determine the prevalence and patterns of shoulder pain amongst Malaysian men's wheelchair basketball (WCBB) players. Furthermore, factors that are associated with shoulder pain were investigated.
Materials and Methods: Eleven national WCBB players participated in this study. All players completed the clinical research forms which collected socio-demographic information, WCBB participation and history of shoulder pain. Assessments of shoulders range of motion, isometric muscle strengths and clinical shoulder tests were performed on all players.
Results: The prevalence of shoulder pain amongst Malaysian WCBB players was 36.4%. Players with current shoulder pain had significantly higher Performance Corrected Wheelchair User's Shoulder Pain Index (PC-WUSPI) scores (13.8 vs. 3.3, P = 0.02) and a greater number of positive shoulder clinical tests (3.5 vs. 1.0, P = 0.04) than players without pain. Players with shoulder pain are frequently diagnosed with rotator cuff injuries, particularly involving the supraspinatus and subscapularis muscles. A significant moderately strong positive correlation between PC-WUSPI score and number of positive clinical shoulder tests was found (r = 0.71; P = 0.01).
Conclusions: Prevalence and patterns of shoulder pain amongst Malaysian men's WCBB players are comparable to previous studies. A strong association between PC-WUSPI score and number of positive clinical shoulder tests suggests a potential role of regular PC-WUSPI assessment for early detection of shoulder problems amongst players.

Keywords: Arthralgia, para-athletes, soft-tissue injuries, upper extremity

How to cite this article:
Hamid MF, Hamid MS. Prevalence of shoulder pain amongst Malaysia men's wheelchair basketball players: A cross-sectional study. Malays J Mov Health Exerc 2022;11:97-107

How to cite this URL:
Hamid MF, Hamid MS. Prevalence of shoulder pain amongst Malaysia men's wheelchair basketball players: A cross-sectional study. Malays J Mov Health Exerc [serial online] 2022 [cited 2023 Jun 2];11:97-107. Available from: http://www.mohejournal.org/text.asp?2022/11/2/97/370242

Introduction

Wheelchair basketball (WCBB) is a basketball adaptation for people with different physical abilities. WCBB was first played in 1945 at two World War II veterans' hospitals and was later contested in the 1960 Paralympic Games (International Wheelchair Basketball Federation, 2017). The Malaysia WCBB Federation was established in 2005 and the National Men's WCBB had participated in several international competitions, including the South East Asia (SEA) Para games and the Asia Paralympics. Despite being a relatively young team, the Malaysia Men's WCBB team was crowned the champion of Division 2 Asia Oceania Championships champion in 2019.

WCBB is played on a standard basketball court with some modifications of rules and regulations. WCBB is a high-intensity and fast-paced sport played by two teams (five players per team) over four periods of 10 min. Individuals with impaired muscle power, athetosis, impaired range of motion (ROM), hypertonia, limb deficiency, ataxia and leg length difference are eligible to participate in WCBB. Each player is classified based on a point system which ranges from 1 to 4.5 points, based on individual's trunk control and sitting balance. Players with higher restrictions will be given a lower point and vice versa. A WCBB team must always consist of five players with a summing point of 14 or less.

WCBB players rely heavily on the upper limbs for rapid wheelchair propulsion, ball handling, passing, blocking and shooting activities (International Wheelchair Basketball Federation, 2016). In addition, wheelchair users rely on their upper limbs for their daily living activities, including transferring and mobility. Hence, the shoulder joint becomes a weight-bearing and stability joint besides for mobility (Curtis et al., 1995). The WCBB activities combined with activities of daily living placed excessive physical stress on the shoulder potentially predisposing players to injuries. It was reported between 29% and 72% of wheelchair users who experienced shoulder pain. Long training hours and busy competition schedules have been associated with a higher incidence of shoulder injuries amongst WCBB players (Curtis and Black, 1999). Shoulder pain may have an adverse effect on the player's ability to perform activities and could affect a person's quality of life. Moreover, secondary complications, including obesity, pressure ulcers, scoliosis and decreased cardiorespiratory fitness, have been reported (Curtis et al., 1995). Current literatures on shoulder injuries amongst WCBB players are based on studies from western countries (Curtis and Black, 1999; Huzmeli et al., 2017). Data on shoulder injury/pain amongst WCBB players in Malaysia and the SEA regions are not available.

Hence, this study aims to investigate the prevalence of shoulder pain amongst Malaysian WCBB players. In addition, patterns of shoulder pain and factors associated with shoulder pain were examined. It is hoped that this study will establish data amongst Malaysian WCBB players and will inspire further research amongst Malaysia's physically disabled athletes.

Materials and Methods

A cross-sectional study was conducted amongst Malaysian men's WCBB players at the Kampung Pandan Sports Complex. A universal sampling method was used where all players were invited to participate in the study. Information about the study, including its purpose and procedures involved, was explained to potential participants via the patient information sheets. Participants were required to complete the informed consent form before participation. Data collection was performed in November 2017.

Participants' socio-demographic data were collected via group interview using a standardised clinical research form (CRF) [Appendix 1] [Additional file 1]. The CRF was designed to capture socio-demographic data, including date of birth, ethnic background, marital status, occupation, cause of disability, years of disability, years of wheelchair use, number of daily wheelchair transfers, years involved in WCBB, frequency of training per week, duration/hours of training per session, medical history of shoulder pain and current shoulder pain as well as the treatment received. Participants were assisted by the investigator (MFAH) in completing the CRF, where available results of appropriate radiological imaging reports were retrieved and documented in the players' CRF.

Wheelchair users' shoulder pain index

Upon completion of the CRF, participants were required to complete the Wheelchair User's Shoulder Pain Index (WUSPI) questionnaire [Appendix 2] [Additional file 2]. The WUSPI is a 15-item questionnaire that represents the participants' perception of shoulder pain during functional activities such as transferring to a car, pushing up ramps or inclinations, sleeping and others (Curtis et al., 1995). For each functional activity, participants were required to indicate on 10-cm Visual Analogue Scale symptoms of pain anchored at 0 = 'no pain' and 10 = 'worst pain ever experienced'. Each item scored was added to yield a total score from a minimum of 0 to a maximum of 150. For individuals who are unable to perform certain functions listed in the WUSPI, such as those with tetraplegia or part-time wheelchair users (those who use the wheelchair for sports participation), the Performance Corrected WUSPI (PC-WUSPI) will be calculated as described by previous studies (Curtis and Black, 1999; Brose et al., 2008; Gutierrez et al., 2007; Nawoczenski et al., 2006; Yildirim et al., 2010). The PC-WUSPI score is calculated by dividing the total WUSPI score by the number of activities performed and then multiplying by 15.

WUSPI is a valid and reliable tool and has been used widely for measuring shoulder pain amongst wheelchair users. In previous studies, WUSPI has high test–retest reliability (ICC = 0.99) and also high internal consistency (α = 0.97) (Curtis et al., 1995).

All participants underwent a structured physical assessment, including an examination of both shoulders. The shoulder examination involved an assessment of the shoulder ROM, clinical shoulder tests and shoulder muscle strength. MFAH performed all assessments with participants in the sitting position.

Range of motion (ROM)

A universal goniometer was used to measure the shoulder ROM. Shoulder flexion, extension, abduction, adduction, internal rotation and external rotation of both shoulders were evaluated using the method described by Clarkson (Clarkson, 2005). Measurements of the shoulder range of motion were performed in a sitting position to prevent any unnecessary transfer and repositioning (Burnham et al., 1993). For each movement, two readings were recorded in the CRF, and the average value was used in the final analysis.

Isometric shoulder muscle strength

Isometric shoulder muscle strength was evaluated using a handheld dynamometer PowerTrack™ II Commander (JTech, USA). A previous study reported good-to-excellent intra- and inter-tester reliability using this method of assessment (Dollings et al., 2012). Isometric shoulder muscle strength during shoulder abduction, shoulder flexion, internal rotation and external rotation was recorded in the player's CRF. A universal goniometer was used to standardise the position of the shoulder and elbow during the assessment to ensure consistency. The protocols for shoulder muscle strength assessment were adapted from Dollings et al. 2012 (Dollings et al., 2012).

Clinical shoulder tests

Clinical tests for the rotator cuff muscle group, biceps muscle, shoulder impingement and shoulder instability tests were performed using the techniques described by previous studies [Table 1] (Hill et al., 2008; Jain et al., 2013).

Table 1: Clinical shoulder tests (Hill et al., 2008; Jain et al., 2013)

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The sample size was estimated using the online sample size calculator (calculator.net) based on a previous study. With a confidence level set at 80%, margin of error of 5% and shoulder pain prevalence of 26% (Curtis and Black, 1999), an estimated sample size of 127 basketballers is needed.

Data were analysed using the Statistical Package for the Social Sciences (SPSS Inc., version 24.0 for Mac, Chicago, Illinois, USA). A descriptive analysis of participants' characteristics was performed. Continuous variables, including participants' socio-demographic and measured variables, were reported using mean and standard deviation (SD) or median and interquartile range, depending on the data distribution. Normal distribution of the data was assumed when the Shapiro–Wilk test had P < 0.05. Categorical data were presented as frequencies and percentages. The Spearman correlation test was used to determine the relationship between age, years of wheelchair use, number of transfers per day, driving hours, BMI, and the WUSPI scores. Chi-square tests were performed to analyse the relationship between categorical variables and WUSPI score. Based on the data distribution, the shoulder ROM and isometric shoulder strength of the painful and non-painful shoulders were compared using a paired t-test or a Wilcoxon signed rank test. A similar analysis was performed on the dominant versus non-dominant shoulders amongst WCBB without current shoulder pain.

The present study protocol was reviewed and approved by the Medical Centre Ethics Committee of the University of Malaya (MEC Ref. No. 2017724-5429). Information about the study, including its purpose and procedures involved, was explained to potential participants via the patient information sheets. Participants were required to complete the informed consent form before participation.

Results

Eleven Malaysian male national WCBB players participated in this study, with a total of 22 shoulders examined. Participants' socio-demographic information is displayed in [Table 2]. All players were full-time athletes and spent an average of 28 h of training time per week. Two players only use the wheelchair during WCBB activities as they can ambulate with crutches (lower limb deficiency). Players' daily activity requires them to transfer from and to a wheelchair on average of 10 times every day. The mean years of involvement in WCBB were 7.5 ± 4.0 (SD) years.

Table 2: Wheelchair basketball players' characteristics

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Shoulder pain and wheelchair user shoulder pain (WUSPI)

Four players (36.4%) reported current shoulder pain during the study. Two players (18.2%) reported pain on the non-dominant shoulder, one player reported pain on the dominant side and another had pain on both shoulders. Players with shoulder pain had significantly higher WUSPI scores than those who reported no pain (13.76 ± 8.43 vs. 3.33 ± 4.21; P = 0.021). Furthermore, players with shoulder pain had longer WCBB experience (13 years vs. 6 years); this difference, however, is not statistically significant (P = 0.05). No statistically significant differences were found in the mean age, height, weight, WCBB years of experience, number of transfers per day and classification point between players with and without shoulder pain [Table 3]. A significant strong positive correlation between the PC-WUSPI score and the duration of wheelchair use (r = 0.80; P = 0.03) was noted.

Table 3: Wheelchair basketball players' characteristics with and without shoulder pain

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Shoulder range of motion (ROM) and isometric shoulder muscle strength

Amongst WCBB players with current shoulder pain, both the shoulder ROM and isometric shoulder muscle strength of the painful shoulder were lower compared to the non-affected side. The difference, however, was not statistically significant (P > 0.05). No statistically significant differences (P > 0.05) were found in the shoulder ROM (in all directions) and the isometric shoulder muscle strength between the dominant and non-dominant sides amongst WCBB without shoulder pain.

Clinical shoulder tests

Based on the specific clinical tests, most players with shoulder pain (n = 3; 75%) had more than one positive clinical test on the painful shoulder. The possible differential diagnoses of shoulder pain based on clinical tests were supraspinatus muscle/tendon injury, shoulder impingement, subscapularis and biceps muscle/tendon injuries. Three of the WCBB players had an ultrasonogram of the shoulder, which confirmed the diagnosis of the supraspinatus, biceps tendinopathies and shoulder impingement. All players were under the care of a sports physician at the NSMC.

Amongst players who did not report any shoulder pain, clinical tests were positive in five (72%) of the players, including the Belly press, Neer's, Speed's and load-and-shift tests [Table 4]. There is a significantly moderately strong positive correlation between PC-WUSPI score and number of positive clinical shoulder tests (r = 0.71; P = 0.01).

Table 4: Characteristics of players' clinical shoulder tests

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Discussion

Our results found that 45% of Malaysian WCBB players have experienced shoulder pain. During the study, 36.4% of the players have shoulder pain. Shoulder pain prevalence of between 26% and 52% was reported by previous studies (Curtis and Black, 1999; Finley and Rodgers, 2002; Fullerton et al., 2003). Rocco and Saito (2006) revealed that 43% of state-level male WCBB players had shoulder pain. As compared to Rocco and Saito (2006), the current study involved full-time national-level male WCBB players with longer playing experience. Therefore, the lower prevalence of shoulder pain in this study could be related to the difference in aspects of training, including training hours (21 vs. 28 h/week), activities and intensity, as such players might have benefited from the injury preventive training effect (e.g. shoulder muscle strength and endurance) (Rocco and Saito, 2006).

Three shoulder pains occurred on the non-dominant side, with the remaining two shoulders affecting the dominant side. This finding is consistent with You et al. (2016) who reported rotator cuff tendinopathies more frequently diagnosed in the non-playing arm (non-dominant) of wheelchair table tennis players and wheelchair archers (You et al., 2016). They suggested that repetitive shoulder adduction and internal rotation during transfer and wheelchair propulsion amongst athletes could be the predisposing factors to rotator cuff injury (Brose et al., 2008; You et al., 2016; Lim et al., 2014). Yasar, 2008, studied the training pattern of reported similar repetitive shoulder movements performed by WCBB players. Majority of the Turkish WCBB players focused on wheelchair propulsion activities, passing drills (both hands and single hand), picking up the ball off the floor and basket shooting (Yasar, 2008).

No significant differences in the socio-demographic factors between the players with and without shoulder pain were observed in this study. Furthermore, no statistically significant differences were found in the number of transfers per day, years of WCBB experience and athlete's classification point. This observation is in agreement with earlier studies (Curtis et al., 1995; Finley and Rodgers, 2002; Fullerton et al., 2003; Rocco and Saito, 2006).

The PC-WUSPI score amongst players with current shoulder pain in our study was significantly (P = 0.021) higher compared to asymptomatic players. This finding is anticipated, given the high level of reliability and internal consistency of WUSPI (Curtis et al., 1995). A comparable observation was reported by Curtis and Black, 1999 and Yildrim et al., 2010, amongst long-term wheelchair users and wheelchair basketballers, respectively (Curtis and Black, 1999; Yildirim et al., 2010). Curtis and Black (1999) reported that female WCBB players with shoulder pain had higher WUSPI scores with an average of 26.3 ± 22.6 points compared to those without shoulder pain with an average of 3.2 ± 6.1 points (Curtis and Black, 1999). Interestingly, 57% of players who do not report current shoulder pain documented pain in the WUSPI questionnaires. Such observation is not surprising as the WUSPI questionnaires assessed pain sensation for the past week, and there is a possibility that some players may have fully recovered at the time of the study.

Shoulder ROM and isometric shoulder muscle strength were assessed in four planes of movement in our study, including shoulder abduction, forward flexion, internal rotation and external rotation. In general, both the shoulder ROM and the shoulder isometric muscle strength were greater in the non-painful side in all planes. The difference could be due to pain to the shoulder that could inhibit further muscle contraction, thus reducing the overall shoulder muscle strength. This phenomenon is known as arthrogenic muscle inhibition, which is described as a diminished ability to recruit all motor units to their full extent during maximal contraction thought to be associated with pain, effusions or altered afferent return (Hopkins and Christopher, 2007). A previous study amongst wheelchair athletes with shoulder impingement found a significant weakness on shoulder adductors and external and internal rotators (Burnham et al., 1993). It is possible that the difference observed in the current study could reach significant levels if more WCBB players with shoulder pain were included.

Majority of the WCBB players with current shoulder pain had at least one positive clinical shoulder test. Based on the individual tests, potential diagnoses of supraspinatus injury (50%), subacromial impingement (37.5%), biceps tendon injury (37.5%), subscapularis injury (37.5%), infraspinatus injury (12.5%) and shoulder instability (12.5%) were made. In three of the WCBB players, the diagnosis was confirmed by diagnostic ultrasound. Our findings are similar to those reported by previous studies; rotator cuff injury and shoulder impingement were the most frequent injuries reported amongst wheelchair athletes (Burnham et al., 1993; Finley and Rodgers, 2002; You et al., 2016). The supraspinatus muscle is one of the most important dynamic stabilisers of the glenohumeral joint during shoulder activities and positions (Yildirim et al., 2010; Burnham et al., 1993). Thus, supraspinatus injury is commonly related to overloading and overuse in sports with the repetitive overhead movement of the shoulder.

Interestingly, the clinical shoulder tests amongst WCBB players without pain were positive for supraspinatus injury (20%), shoulder impingement (20%), biceps tendon injury (20%) and shoulder instability (7.1%). This might suggest that repetitive overhead activities associated with WCBB activities may have led to cumulative injuries of the muscle and/or tendon that has yet to become symptomatic. Such injuries could become symptomatic during clinical assessment, particularly involving provocative clinical assessment. It is possible that further activities might lead to progress to symptomatic pain, which could affect shoulder function. Moreover, a moderately strong positive correlation between PC-WUSPI seen in this is also interesting. This finding suggested that regular serial PC-WUSPI and clinical shoulder tests might allow early identification of players that are at risk of progressing into symptomatic shoulder conditions. Hence, a longitudinal prospective study to explore the role of serial PC-WUSPI and clinical shoulder tests is recommended.

Several limitations need to be addressed in this study. First, this study involved a small number of players, which may affect the statistical analysis of the data. The number of participants in the current study, however, does reflect the current WCBB situation in Malaysia. Moreover, there is no local WCBB league, nor is there regular competition. Second, the physical assessment performed amongst players with shoulder pain could exacerbate the sensation of pain and must be interpreted with caution. A baseline assessment of physical attributes as well as PC-WUSPI score of players would be useful in identifying players at risk of injury. Moreover, serial PC-WUSPI might allow early injury detection for instilling appropriate injury preventive and intervention. Third, the diagnoses made in the current study, especially amongst players without shoulder pain, were only based on clinical evaluation with each specific test. It should be reminded that tests differ in the level of sensitivity and specificity in the detection of a specific condition. Although the same physician performed all assessments, radiological confirmations such as ultrasound or magnetic resonance imaging could improve the accuracy of the diagnoses. However, due to financial constraints, such tests were not performed in this study.

Conclusion

The prevalence of shoulder pain amongst Malaysian WCBB players is high. WCBB players with current shoulder pain had significantly higher PC-WUSPI scores and more positive clinical shoulder tests compared to players without pain. A significantly strong positive relationship between PC-WUSPI score and number of clinical shoulder tests was found.

Acknowledgements

The authors thank the University of Malaya, the National Sports Institute of Malaysia, the Malaysian WCBB Federation and the Malaysian WCBB Team for their support of this study.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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