Characteristics of included studies. Mean unless otherwise stated
| Author | Recruited | Dropout rate (% of total recruited), reason and number included | Population characteristics of total sample | Method of measuring dyskinesis | Follow-up duration and method of injury reporting | Prevalence and severity of shoulder pain events (% of total included in meta-analysis) |
| Clarsen et al
24 (modified) | 206 elite handball players With and without self-reported shoulder pain but nil on testing Participants with self-reported pain at baseline excluded from meta-analysis | n=42 20.38% Did not complete sufficient questionnaires 164 analysed in study 110 meta-analysed | Age 24 (SD 4) All male Height 189 cm (SD 7) Weight 89 kg (SD 10) Playing age 14 years (SD 5) Elite playing age 4 years (SD 4) Right handed (73%) Back players (42%) Wing players (23%) Line players (15%) Goalkeepers (14%) Combination of positions (6%) | Live visual observation by one physiotherapist, with video playback if uncertain 5× reps of shoulder flexion and abduction using 5 kg weights Categorised as subtle dyskinesis, obvious dyskinesis or normal | One season—9 months. OSTRC overuse injury questionnaire emailed to all players every second Sunday— total 15 questionnaires If <4 questionnaires returned, data excluded. Each questionnaire gives a severity score (0–100). Average severity score = sum of scores/number of questionnaires. Injury = cut-off in study >40 cut-off in meta-analysis>0 | n=44 40% Average cumulative severity score: 9.91 (SD 13.34) |
| Kawasaki et al 36 | 70 elite rugby players | n=8 11.42% Retired for reasons unrelated to the shoulder 62 meta-analysed | Age 24.6 (SD 3.3) All male BMI 28.9 (SD 3.6) Playing age 12.7 (SD 4.8) Position (forward: backward) 61:42 Dominant side (right: left) 99:4 Frequent collision side (right: equal: left) 65:30:8 | Live visual observation by two sports doctors, with video playback if uncertain 5× reps of shoulder flexion and abduction in scapular plane using 3 kg weights. Categorised as type 1–3 dyskinesis or type 4 = Normal | One elite Japanese rugby season—length not specified— via questionnaire Injury = subjective discomforts (pain, apprehension or fatigue) persisting more than 2 weeks; and shoulder trauma requiring off-game>7 days | n=25 40.3% Discomfort persisting >2 weeks Severity not reported |
| McKenna et al 35 (modified) | 46 adolescent swimmers 43 adolescent non-swimmers (excluded) | n=4 4.49% Did not respond to questionnaire All from non-swimmer group 46 meta-analysed. | [no pain, pain] Female gender: 65.7%, 63.6% Age (years) 14.5 (SD 1.4), 14.9 (SD 1.7) Matured by start of study: 51.6%, 45.5% Previous shoulder or arm pain: 35.3%, 50.0% Number of weekly training sessions 6.7 (3–10), 6.6 (5–10) Swimming age (years) 3.6 (SD 2.6) 4.7 (SD 2.3) Freestyle swim time (seconds) 67.1 (SD9.1), 66.1 (SD6.5) Height (m) 1.65 (SD 0.09), 1.65 (SD 0.09) Weight (kg) 54.7 (SD 10.4), 57.9 (SD 9.7) BMI** 19.8 (SD 2.3), 21.3 (SD 2.2) Chest width (cm) 30.1 (SD 3.1), 30.0 (SD2.9) | Anthropometric tape measures In neutral, hands on hips, 90 degrees’ abduction + internal rotation and full flexion Distances measured between: T7 → inferior scapula T3 → medial spine scapula Humeral head position in relation to acromion using palpation, photography and digital calculation Cut-off for dyskinesis determined by post hoc receiver operated curve analysis to find best fit sensitivity/specificity. | 12 months later via questionnaire Injury = positive answer to the question ‘Have you had any pain in your shoulder in the last year?’ | n=11 23.91% Severity not reported. |
| Shitara et al
34 (modified) | 132 high school baseball pitchers With and without self-reported shoulder pain, but nil on testing Participants with self-reported pain at baseline excluded from meta-analysis. | n=27 26.87% Failed to provide consent or did not complete questionnaire 105 analysed in study. 88 meta-analysed. | Median age 16.3 (SD 0.6) All male Baseball experience (years) Non-injured 8.1 (SD 2.0) Injured mean 8.4 (SD 2.2) Past shoulder pain Non-injured 34 (40.5%) Injured 7 (33.3%) Past elbow pain Non-injured 44 (52.4%) Injured 13 (61.9) Present shoulder pain (excluded) Non-injured 12 (14.3%) Injured 5 (23.8%) Present elbow pain Non-injured 19 (22.6%) Injured 6 (28.6%) | Live visual observation by two orthopaedic surgeons, with video playback if uncertain 3–5× reps of shoulder flexion and abduction in scapular plane without weights Categorised as yes/no | One high school baseball season—length not specified Self-reported at medical check-ups and via end of season questionnaire Injury = unable to participate in training/games for ≥8 days Injuries from other mechanisms than throwing excluded. | n=16 18.18% Required >7 days of missed participation in training/game Severity not reported. |
| Struyf et al 37 | 196 recreational overhead athletes: Volley ball 37 Tennis 26 Baseball 5 Badminton 35 Handball 10 | n=83 42% Not willing to be contacted, cessation of overhead activity, no reason, emigration or impossible to get in contact with 113 meta-analysed. | Age 34 (SD 12) Men (48%) Right handed (89%) Must play >1 hour per week of preferred sport | Live visual observation by one physiotherapist Static: At rest, hands on hips, hands at 90° abduction Dynamic: 3× reps of shoulder abduction without weights Categorised as winging, forward tilt or normal | 24 months Contacted by phone at 12 and 24 m Injury = any physical complaint recalled lasting at least 1 day in the previous month, irrespective of disability induced Severity measured with Shoulder Disability Questionnaire. | n=25 22% Mean SDQ =34.8 (SD 17.4) |
Modified data excluded the results of participants with pain at baseline in two studies30 39 or dichotomisation of continuous measurements of scapular position in one study.40
**Indicates a significant difference between groups.
BMI, body mass index; OSTRC, Oslo Sports Trauma Research Centre; Reps, repetitions; SDQ, Shoulder Disability Questionnaire.