Prediction of Shoulder Pain in Youth Competitive Swimmers: The Development and Internal Validation of a Prognostic Prediction Model.

BACKGROUND: Knowledge of predictors for shoulder pain in swimmers can assist professionals working with the athlete in developing optimal prevention strategies. However, study methodology and limited available data have constrained a comprehensive understanding of which factors cause shoulder pain. PURPOSE: To investigate risk factors and develop and internally validate a multivariable prognostic model for the prediction of shoulder pain in swimmers. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: A total of 201 pain-free club- to international-level competitive swimmers were followed for 2 consecutive seasons. The cohort consisted of 96 male (mean ± SD age, 13.9 ± 2.2 years) and 105 female (13.9 ± 2.2 years) swimmers. Demographic, sport-specific, and musculoskeletal characteristics were assessed every 6 months. Swim-training exposure was observed prospectively. Shoulder pain interfering with training was the primary outcome. Multiple imputation was used to cope with missing data. The final model was estimated using multivariable logistic regression. We applied bootstrapping to internally validate the model and correct for overoptimism. RESULTS: A total of 42 new cases of shoulder pain were recorded during the study. Average duration of follow-up was 1.1 years. Predictors included in the final model were acute:chronic workload ratio (odds ratio [OR], 4.31; 95% CI, 1.00-18.54), competitive level (OR, 0.19; 95% CI, 0.06-0.63), shoulder flexion range of motion, posterior shoulder muscle endurance (OR, 0.96; 95% CI, 0.92-0.99), and hand entry position error (OR, 0.37; 95% CI, 0.16-0.91). After internal validation, this model maintained good calibration and discriminative power (area under the receiver operating characteristic curve, 0.71; 95% CI, 0.60-0.94). CONCLUSION: Our model consists of parameters that are readily measurable in a swimming setting, allowing the identification of swimmers at risk for shoulder pain. Multivariable logistic regression showed the strongest predictors for shoulder pain were regional competitive swimming level, acute:chronic workload ratio, posterior shoulder muscle endurance, and hand entry error.

Monitoring the swimmer's training load: A narrative review of monitoring strategies applied in research.

The high incidence of injury during swim training and the increasing demands of the sports make monitoring of the swimmer's training load a key concept requiring further investigation. Research has previously introduced numerous methods for the purposes of monitoring the swimmer's training load, but a narrative review discussing the strengths and limitations of each method is lacking. Consequently, this narrative review aims to summarize the monitoring strategies that have been applied in research on competitive swimmers. This knowledge can assist professionals in the field in choosing which method is appropriate in their particular setting. The results from this study showed that external training load was predominantly obtained through real-life observation of the swimmers' training volume. However, research has investigated a number of internal load monitoring tools, including blood lactate, training heart rate, and perceived effort of training. To date, blood lactate markers are still considered most accurate and especially recommended at higher levels of competitive swimming or for those at greater risk of injury. Further, mood state profiling has been suggested as an early indicator of overtraining and may be applied at the lower competitive levels of swimming. Professionals in the field should consider the individual, the aim of the current training phase, and additional logistical issues when determining the appropriate monitoring strategy in their setting.

Intrarater and Interrater Reliability of a Passive Shoulder Flexion Range of Motion Measurement for Latissimus Dorsi Flexibility in Young Competitive Swimmers.

CONTEXT: The latissimus dorsi plays a major role in generating the propulsive force during swimming. In addition, stiffness of this muscle may result in altered stroke biomechanics and predispose swimmers to shoulder pain. Measuring the flexibility of the latissimus dorsi can be of interest to reduce injury. However, the reliability of such measurement has not yet been investigated in competitive swimmers. OBJECTIVE: To assess the within-session intrarater and interrater reliability of a passive shoulder flexion range of motion measurement for latissimus dorsi flexibility in competitive swimmers. DESIGN: Within-session intrarater and interrater reliability. SETTING: Competitive swimming clubs in Flanders, Belgium. PARTICIPANTS: Twenty-six competitive swimmers (15.46 [2.98] y; 16 men and 10 women). INTERVENTION: Each rater performed 2 alternating (eg, left-right-left-right) measurements of passive shoulder flexion range of motion twice, with a 30-second rest period in between. MAIN OUTCOME MEASURES: The intraclass correlation coefficients were calculated to assess intrarater and interrater reliability. RESULTS: Interrater intraclass correlation coefficient ranged from .54 (95% confidence interval [CI], -.16 to .81) to .57 (95% CI, -.24 to .85). Results for the intrarater reliability ranged from .91 (95% CI, .81 to .96) to .94 (95% CI, .87 to .97). CONCLUSION: Results of this study suggest that shoulder flexion range of motion in young competitive swimmers can be measured reliably by a single rater within the same session.

Swim-Training Volume and Shoulder Pain Across the Life Span of the Competitive Swimmer: A Systematic Review.

BACKGROUND: Competitive swimmers are exposed to enormous volumes of swim training that may overload the soft tissue structures and contribute to shoulder pain. An understanding of training factors associated with the injury is needed before practice guidelines can be developed. OBJECTIVES: To investigate the relationship between swim-training volume and shoulder pain and to determine swim-training volume and shoulder pain prevalence across the life span of the competitive swimmer. DATA SOURCES: Relevant studies within PubMed, Web of Science, and MEDLINE. STUDY SELECTION: Studies that assessed the relationship between a defined amount of swim training and shoulder pain in competitive swimmers. DATA EXTRACTION: Twelve studies (N = 1460 participants) met the criteria. Swimmers were grouped by age for analysis: young (<15 years), adolescent (15-17 years), adult (18-22 years), and masters (23-77 years). DATA SYNTHESIS: Adolescent swimmers showed the highest rates of shoulder pain (91.3%) compared with other age groups (range = 19.4%-70.3%). The greatest swim-training volumes were reported in adolescent (17.27 ± 5.25 h/wk) and adult (26.8 ± 4.8 h/wk) swimmers. Differences in exposure were present between swimmers with and those without shoulder pain in both the adolescent (P = .01) and masters (P = .02) groups. In adolescent swimmers, the weekly swim-training volume (P < .005, P = .01) and years active in competitive swimming (P < .01) correlated significantly with supraspinatus tendon thickness, and all swimmers with tendon thickening experienced shoulder pain. CONCLUSIONS: Evidence suggests that swim-training volume was associated with shoulder pain in adolescent competitive swimmers (level II conclusion). Year-round monitoring of the athlete's swim training is encouraged to maintain a well-balanced program. Developing athletes should be aware of and avoid a sudden and large increase in swimming volume. However, additional high-quality studies are needed to determine cutoff values in order to make data-based decisions regarding the influence of swim training.

Rotator CUFF disorders: A survey of current physiotherapy practice in Belgium and the Netherlands.

BACKGROUND: Disorders of the rotator cuff are a common musculoskeletal pain presentation in the general population, and treatment by a physiotherapist is often prescribed. In 2011, 2016, surveys of physiotherapy practice in the United Kingdom (UK) were performed, which reported that advice and exercise were the most common treatment strategies used. The aim of this current survey was to examine current physiotherapy practice in Belgium and The Netherlands, with consideration of differences between physiotherapists who were members of a shoulder network and physiotherapists who were not. METHODS: During February/March 2018, a cross-sectional online survey was conducted in Belgium and The Netherlands. RESULTS: 505 physiotherapists completed the survey. Advice (n = 362/505), isotonic exercises (n = 302/505) and scapular stabilisation exercises (n = 359/505) were the most common treatment modalities for patients with rotator cuff disorders. Physiotherapists not part of a shoulder network group more commonly integrated mobilization (n = 66/254 SN, n = 125/251 N-SN), electrotherapy (n = 1/254 SN, n = 19/251 N-SN) and massage (n = 48/254 SN, n = 89/251 N-SN) compared to those who were member of the group. CONCLUSION: Advice and exercise were the most common treatment prescriptions, which aligns with recommendations from current research evidence. Practice differs between physiotherapists involved with a shoulder network group compared to those who are not.

Training volume is associated with pain sensitivity, but not with endogenous pain modulation, in competitive swimmers.

OBJECTIVES: To investigate the association of pain sensitivity and endogenous analgesia capacity, and training volume in a group of competitive swimmers. DESIGN: An observational multi-center study. SETTING: Multiple competitive swimming clubs. PARTICIPANTS: 102 healthy competitive swimmers. MAIN OUTCOME MEASURES: Training volume was estimated using self-reported information. Static and dynamic measures of pain were assessed using pressure pain thresholds (PPTs) and conditioned pain modulation (CPM), the latter as a measure of endogenous pain inhibition. Selected demographic and psychosocial measures were considered as possible confounding factors. RESULTS: Moderate positive correlations (0.38 < r < 0.44; p < 0.01) exist between self-reported training volume and PPTs at widespread body areas in competitive swimmers. These results were maintained during linear regression analysis while addressing possible confounding factors such as age and selected psychosocial factors. No associations were found between self-reported training volume and conditioned pain modulation (-0.08 < r < 0.06; p > 0.05). CONCLUSIONS: Self-reported swim training volume is associated with pain sensitivity in competitive swimmers. Swimmers who train more show higher pressure pain thresholds, indicating lower pain sensitivity. Swim training volume is not associated with endogenous nociceptive inhibitory capacity as determined using CPM.

Intra- and interrater reliability of the 'lumbar-locked thoracic rotation test' in competitive swimmers ages 10 through 18 years.

OBJECTIVES: Measuring thoracic spine mobility can be of interest to competitive swimmers as it has been associated with shoulder girdle function and scapular position in subjects with and without shoulder pain. At present, no reliability data of thoracic spine mobility measurements are available in the swimming population. This study aims to evaluate the within-session intra- and interrater reliability of the "lumbar-locked rotation test" for thoracic spine rotation in competitive swimmers aged 10 to 18 years. This reliability study is part of a larger prospective cohort study investigating potential risk factors for the development of shoulder pain in competitive swimmers. DESIGN: Within-session, intra- and inter-rater reliability. SETTING: Competitive swimming clubs in Belgium. PARTICIPANTS: 21 competitive swimmers. MAIN OUTCOME MEASURES: Intra- and inter-rater reliability of the lumbar-locked thoracic rotation test. RESULTS: Intraclass correlation coefficients (ICCs) ranged from 0.91 (95% CI 0.78 to 0.96) to 0.96 (0.89-0.98) for intra-rater reliability. Results for inter-rater reliability ranged from 0.89 (0.72-0.95) to 0.86 (0.65-0.94) respectively for right and left thoracic rotation. CONCLUSION: Results suggest good to excellent reliability of the lumbar-locked thoracic rotation test, indicating this test can be used reliably in clinical practice.

Musculoskeletal dysfunctions associated with swimmers' shoulder.

Shoulder pain is the most reported area of orthopaedic injury in swimmers. The so-called 'swimmers' shoulder' has been applied to a variety of complaints involving shoulder pain in swimmers without specific reference to contributing mechanisms or structures. Knowledge of dysfunctions associated with swimmers' shoulder can assist clinicians in developing rehabilitation strategies. This literature review aims at providing clinicians insight into the musculoskeletal mechanisms and impairments associated with swimmers' shoulder that could aid them in developing rehabilitation strategies. The following musculoskeletal dysfunctions will be discussed: muscle activity, strength, endurance, muscle control, range of motion, glenohumeral laxity, glenohumeral instability, shoulder posture and scapular dyskinesis. The findings in this review may have implications for swimmers, their coaches, and rehabilitation specialists working with swimmers.