Original research Shoulder pain in swimmers: A 12-month prospective cohort study of incidence and risk factors Helen Walker a , Belinda Gabbe b , Henry Wajswelner c , Peter Blanch d , Kim Bennell a, * a Centre for Health Exercise and Sports Medicine, Department of Physiotherapy, The University of Melbourne, Parkville, Victoria 3010, Australia b School of Public Health and Preventive Medicine, Monash University, Victoria, Australia c DMA Clinical Pilates, Victoria, Australia d Department of Physical Therapies, Australian Institute of Sport, Australian Capital Territory, Australia article info Article history: Received 15 June 2011 Received in revised form 15 November 2011 Accepted 12 January 2012 Keywords: Shoulder Pain Range of motion Laxity Swimming abstract Objective: To investigate shoulder pain incidence rates and selected risk factors for shoulder pain in competitive swimmers. Design: 12-month prospective cohort study. Setting: Five swimming clubs in Melbourne, Australia. Participants: 74 (37 M, 37 F) competitive swimmers ranging in age from 11 to 27 years and performing at least five swim sessions per week. Assessment of risk factors: Swimmers completed a baseline questionnaire regarding demographics, anthropometric features, swimming characteristics and training and injury history. Active shoulder internal (IR) and external rotation (ER) range of motion and passive joint laxity were measured. Main outcome measurements: Shoulder pain was self-reported over 12 months with significant inter- fering shoulder pain (SIP) defined as pain interfering (causing cessation or modification) with training or competition, or progression in training. A significant shoulder injury (SSI) was any SIP episode lasting for at least 2 weeks. Results: 28/74 (38%) participants reported SIP while 17/74 (23%) reported SSI. Exposure-adjusted inci- dence rates were 0.3 injuries and 0.2 injuries per 1000 swim km for SIP and SSI, respectively. Swimmers with both high and low ER range were at 8.1 (1.5, 42.0) and 12.5 (2.5, 62.4) times greater risk of sustaining a subsequent SIP, respectively and 35.4 (2.8, 441.4) and 32.5 (2.7, 389.6) times greater risk of sustaining a SSI, respectively than those with mid-range ER. Similarly swimmers with a history of shoulder pain were 4.1 (95% CI: 1.3,13.3) and 11.3 (95% CI: 2.6, 48. 4) times more likely to sustain a SIP and SSI, respectively. Conclusion: Shoulder pain is common in competitive swimmers. Preventative programs should be particularly directed at those swimmers identified as being at risk of shoulder pain. Ó 2012 Elsevier Ltd. All rights reserved. 1. Introduction Shoulder pain/injury is the most common musculoskeletal problem experienced by competitive swimmers (McMaster, 1999; Mountjoy et al., 2010; Weldon & Richardson, 2001). Of the rela- tively few studies investigating shoulder injury incidence in this sporting population, reported rates vary widely depending on the specific injury definition employed (Chalmers & Morrison, 2003). Given its prevalence, numerous risk factors for shoulder injury in swimmers are proposed in the literature including glenohumeral joint range of motion and laxity, scapular dyskinesis, rotator cuff strength imbalances, gender, competitive swimming level, stroke, swim distance and hand paddle usage during swim training (Bak, 2010; Blanch, 2004; McMaster, Roberts, & Stoddard, 1998; McMaster & Troup, 1993; Richardson, Jobe, & Collins, 1980; Sein et al., 2010; Weldon & Richardson, 2001; Wolf, Ebinger, Lawler, & Britton, 2009). However, these have received limited prospective investigation (Gaunt & Mafulli, 2011). Biomechanical three dimensional analysis of freestyle swim- ming supports the notion that adequate rotational shoulder range of motion is required to swim with correct technique and avoid shoulder impingement (Yanai & Hay, 2000; Yanai, Hay, & Miller, * Corresponding author. Tel.: þ61 3 8344 4135; fax: þ61 3 8344 4188. E-mail addresses: heljastrav@bigpond.com (H. Walker), belinda.gabbe@ med.monash.edu.au (B. Gabbe), waj5@me.com (H. Wajswelner), p.blanch@ ausport.gov.au (P. Blanch), k.bennell@unimelb.edu.au (K. Bennell). Contents lists available at SciVerse ScienceDirect Physical Therapy in Sport journal homepage: www.elsevier.com/ptsp 1466-853X/$ e see front matter Ó 2012 Elsevier Ltd. All rights reserved. doi:10.1016/j.ptsp.2012.01.001 Physical Therapy in Sport 13 (2012) 243e249