Reduced shoulder strength and change in range of motion are risk factors for shoulder injury in water polo players

Risk Factors for Shoulder Injuries in Female Athletes Playing Overhead Sports: A Systematic Review

CONTEXT

Sports involving overhead motions put substantial biomechanical demands on the shoulder and may result in injuries.

OBJECTIVE

To determine risk factors (RFs) for shoulder injuries in female athletes who play overhead sports and evaluate strategies to reduce shoulder injuries in these athletes.

DATA SOURCES

A systematic electronic search was performed according to Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines. Databases included were PubMed, Tulane Matas Library Search Engine, and Google Scholar, with search terms: "Overhead injuries/Shoulder AND female athletes AND Risk Factors."

STUDY SELECTION

Of the initial 1574 studies identified, 314 were evaluated for eligibility by full-text review and 291 studies were excluded. Overall, 23 studies were included in this study. Studies were published from 2000 to 2021, subject age range was 15 to 35 years, with documented prevalence of shoulder injuries in female athletes playing overhead sports.

STUDY DESIGN

Systematic review.

LEVEL OF EVIDENCE

Level 2.

DATA EXTRACTION

Two independent researchers completed abstract and full-text review. Data extraction used the Covidence and Cochrane Consumer guide template.

RESULTS

Volleyball was the most common sport with shoulder injuries (6/23; 26%) followed by softball 5/23 (22%), swimming 5/23 (22%), gymnastics 4/23 (17%), tennis 3/23 (13%), water polo 2/23 (8%), and basketball 1/23 (4%). Six RFs (dominant shoulder, volume/overuse, time in sport, older age at time of injury, past injury, and multidirectional instability) were described. Of the 23 studies, 9 (39%) identified the dominant shoulder as a RF for sustaining injury (mean risk ratio [RR], 2.04), while 6 (26%) cited volume of repetition and overuse as a prominent RF (RR, 1.45).

CONCLUSION

This systematic review demonstrates important RFs for shoulder injuries in female athletes associated with playing overhead sports. Multiple prevention strategies are described. Prevention programs are helpful in reducing the risk of reinjury.

Relationship between strength training and shoulder pain in male and female water polo players

The objective of this study was to assess the effect of two different strength-training methods on both male and female water polo players' performance and shoulder pain. The players were randomly allocated to a maximum strength (MS: 14 males, 8 females) or power strength (PS: 13 males, 8 females) training group. Before and after the intervention, we assessed player's anthropometric characteristics, shoulder internal and external rotation strength, hand grip strength, upper body strength, countermovement jump height, throwing velocity, swimming speed, shoulder pain on a visual analogue scale (VAS), wellness, and rate of perceived exertion per session. We observed no significant improvement (P<0.05) in specific skills but enhancement in hand grip strength in male players. In female players in the MS group, throwing speed and bench press weight decreased significantly (P<0.05). Shoulder external rotation strength at 240°/sec in male MS group players and shoulder external rotation strength at 60°/sec in female PS group players decreased significantly (P<0.05). In addition, from the first to the last week, shoulder pain increased significantly (P<0.05) in all players. Inverse correlations (P<0.05) were found between VAS and shoulder rotation strength in males in the PS group, and between wellness and shoulder internal rotation strength in men in the MS group and women in the PS group. We found that both MS and PS training did not enhance performance and increased shoulder pain in male and female water polo players.

Relationship Between Pitch Counts and Shoulder Strength in Collegiate Baseball Players

ABSTRACT

Gagnon, A, Payette, J, Park, M, Juras, K, and Slater, L. Relationship between pitch counts and shoulder strength in collegiate baseball players. J Strength Cond Res 37(9): 1860-1864, 2023-Large volumes of throwing leads to changes in shoulder strength that have been associated with increased risk of injury. The purpose of this study was to investigate the relationship between throwing volume and eccentric shoulder strength. Twelve NCAA Division I baseball pitchers volunteered to participate. Prepractice and postpractice eccentric shoulder strength was measured using a handheld dynamometer at 30°/second. Change in strength was calculated as the prepractice strength measure subtracted from the postpractice strength measure. After initial testing, subjects self-reported pitch counts before completing postpractice strength testing. Subjects were separated into high-strength and low-strength groups based on the median external rotation strength. Paired t -tests were used to compare change in shoulder strength and Pearson's r correlations were used to quantify the association between pitches and change in strength. There were no changes between prestrength and poststrength assessments in external rotation strength or internal rotation strength for the entire group. When divided into strength groups, correlations between strength and total pitches were nonsignificant for the high-strength group but were strong for both external rotation ( r = -0.87, p = 0.025) and internal rotation ( r = -0.91, p = 0.013) in the low-strength group. Pitchers with lower shoulder eccentric strength at baseline demonstrated greater declines in strength, whereas pitchers with higher shoulder eccentric strength did not demonstrate changes in strength. Changes in strength during practice could lead to compensatory movement that may predispose athletes to injury. Sport performance professionals may benefit from obtaining eccentric shoulder strength to assist with performance periodization and rehabilitation after injury.

Is there an association between joint range of motion and muscle strength in young female dancers? And, does it depend on the effects of age and menarche?

Aiming to determine the association between joint range of motion (ROM) and muscle strength; and, the effect of age and menarche on those two factors; 132 pre-and post-menarche dancers, aged 12-14 years were assessed for joint ROM and for muscle strength at the hip, knee and ankle and foot joints. En-pointe ROM was significantly correlated with ankle plantar-flexors' (r = -.184) and with ankle dorsiflexors' muscle strength (r = -.221). Hip external rotation ROM was significantly correlated with knee extensors' strength (r = -.263). Pre-menarche dancers had higher joint ROM compared with post-menarche dancers; yet, dancers at post-menarche were stronger compared to dancers at pre-menarche. The slope coefficient was negative at the age of 12 in hip external rotation and in en-pointe (-0.80 and -0.52, respectively) and became steeper with age (age 13: -3.52 and -3.28, respectively; age 14: -6.31 and -4.42, respectively). Along maturation, dancers with high joints ROM showed reduced muscle strength. Pre-menarche dancers have higher joint ROM, yet reduced muscle strength, compared with post-menarche dancers. As the association between joint ROM and muscle strength might be involved with growth and development, young dancers should be screened along pubertal stages in order to decide the correct curricula and to prevent future injuries.

Active range of motion of the shoulder: a cross-sectional study of 6635 subjects

Background

Normative data for passive range of motion are well established, but daily living is comprised of active motion. The purpose of this study was to establish normative values for active range of motion of the shoulder across age, sex, and arm. Our hypotheses were that active range of motion of the shoulder (1) decreases with age group, (2) differs between males and females, and (3) differs between the right arm and left arm.

Methods

Shoulder active range of motion was captured with an eight-camera markerless motion capture system. Data were collected for a heterogenous sample of 6635 males and females of all ages. For each subject, 6 shoulder motions were collected with maximum values measured: external rotation, internal rotation, flexion, extension, abduction, and horizontal abduction. Three-way repeated measures analyses were performed, with 2 between-subject factors (age group and sex) and 1 within-subject factor (arm). The unadjusted threshold for statistical significance was α = 0.05.

Results

External rotation decreased with age (approximately 10° decrease from below 30 years to above 60 years). External rotation was approximately 5° greater in the right arm, whereas internal rotation was approximately 5° greater in the left arm. Flexion decreased with age (approximately 15° decrease from below 20 years to above 60 years). For age groups from 10 to 59 years, extension and horizontal abduction were approximately 5° to 10° greater in females than males. Abduction was greater for females than males. Abduction was also greater in younger people (aged 10-29 years) than older people.

Conclusion

In general, active range of motion of the shoulder decreases with age. Sex (male/female) and arm side (right/left) also influence shoulder range of motion.

Shoulder impingement syndrome in water polo players: muscle shortening manoeuvre controls pain intensity, recovers function and normalizes sonographic parameters

PURPOSE

To evaluate the effects of muscle shortening manoeuvre (MSM) by sonography (US) in professional water polo players with shoulder impingement syndrome (SIS).

METHODS

Twenty-four professional water polo players (mean age: 22.13 ± 3.34) with SIS were assigned to one of 2 different treatment interventions: Group (1) MSM: a series of fast accelerations in the upward direction was applied to the upper limb that's connected to a spring through a metal plate with a ring. The ring was linked to a pulley system that was submitted to forces acting in the opposite direction (added mass). Group (2) Simple traction: the series of fast accelerations were performed without the springs. Pain intensity, Yocum and Hawkins tests for SIS, Neer's impingement sign, range of motion, muscle strength and shoulder US were assessed. The examination was performed before, immediately after and 30 days after each treatment to study the US width of subacromial-subdeltoid bursa (SSB), thickness of supraspinatus (ST), long biceps tendons (LBT); hypoechoic halo of surrounding the long biceps (LBH) and subscapular tendons (STH); width of acromio-clavicular joint capsule (ACJ) and the distance between bone heads (ACD). Impingement sign (IS) was evaluated by dynamic examination.

RESULTS

Immediately after treatment with MSM, pain was much reduced (p = 0.002); Yocum and Hawkins tests were decreased (p = 0.008, p = 0.031); Neer's impingement sign was negative; range of motion and muscle strength were increased. US showed that the following parameters were significantly reduced: SSB (p = 0.001), LBT (p = 0.014), LBH (p = 0.014), SSH (p = 0.002), ACJ (p = 0.004), ACD (p = 0.001). IS was no more detected. After 30 days, the improvement of clinical and US findings was maintained. In the control group, after simple traction, no clinical amelioration of US parameters was found immediately after the procedure.

CONCLUSION

These data show that MSM could be significantly and rapidly effective against pain and the loss of function due to shoulder impingement in water polo players.

The Effectiveness of Shoulder Mobility and Strength Programs in Competitive Water-Polo Players

Background: Water-polo is the water sport with the highest incidence of injuries, with shoulder pain being the most common one. The understanding of risk factors and guidance on preventive measures is essential in this sport discipline. The aim of this study was to determine the effects of a specific 6-week training plan on range of motion (ROM) and joint strength levels in a group of professional water-polo players. Methods: Quasi-experimental study with a sample of 28 participants (age: 20.1 ± 2.5 years; height: 176.9 ± 6.2 cm; body mass: 74.6 ± 8.1 kg). Three study groups, which consisted of one control group and two experimental groups, were established. Two repeated measurements, pre and post intervention, were performed. During these measurements, ROM of the glenohumeral joint was analyzed both in external (ER) and internal (IR) rotation, as well as the maximal isometric strength. Conclusions: The application of a training program improved glenohumeral joint ROM. ER and IR evolve differently in both shoulders. ER improved only in the throwing arm only in the group undergoing intervention but for the non-dominant side, improvements were observed in both ER and IR, regardless of whether or not they had followed the intervention plan. No improvements were observed in either the isometric strength or contralateral asymmetries.

Risk Factors for Shoulder Injuries in Water Polo: a Cohort Study

BACKGROUND

Very limited investigations have been conducted exploring risk factors for injury in water polo players. A gap remains in the literature regarding identification of variables that should be considered as part of player screening evaluations.

PURPOSE

To estimate whether previous injury, changes in strength, range of motion (ROM) or upward scapular rotation (UR) are related to shoulder injuries in water polo players.

STUDY DESIGN

Descriptive cohort study.

METHODS

Thirty-nine international-level players participated (19 males). Shoulder internal (IR) and external rotation (ER) peak torque was measured using an isokinetic device (CONtrex MJ). Shoulder ROM was measured passively using standard goniometry. Scapular UR was measured using a laser digital inclinometer. At baseline players were divided into groups: those with and without previous shoulder injuries. Independent t-tests and Mann-Whitney U tests were used to compare the study variables between groups. After nine months, a second analysis compared the same athletes, who were then grouped by those who had or had not sustained new injuries. Effect sizes were calculated with a Hedge's g. Chi squared analysis compared proportion of injured players with and without previous injury.

RESULTS

Eighteen participants (46%) had previous injuries at baseline. Players with a previous injury showed higher peak torques for IR (0.62±0.15 vs 0.54±0.13N/kg, p=0.04, g=0.60); larger loss of IR ROM (9.9±9.1 vs 4.1±7.5°, p=0.04, g=0.68), but no statistical difference in UR (p=0.70). After nine months, there were no statistical strength differences between groups. Loss of IR ROM was significantly higher in the injured group (9.8±9.8 vs 4.0±6.7°, p=0.04, g=0.68), as well as UR (13.0±3.0 vs 10.4±3.3°, p=0.01, g=0.81). History of previous injury was significantly related to developing a new injury (OR 6.5, p=0.02). Logistic regression found previous injury and UR most important contributors to injury risk.

CONCLUSIONS

Previous injury, changes in IR ROM and UR are related to new shoulder injuries in water polo, but further variables such as rest, training load, or psychosocial factors may explain the incidence of new injuries.

LEVEL OF EVIDENCE

Level 3.

Comparison of the Metabolites of Water Polo Players before and after Competition by the Metabolomic Approach

Background

The metabolic characteristics of body fluids of excellent water polo players before and after competition have not been reported. The purpose of the study was to compare the metabolites in the urine of water polo players before and after competition by 1H-NMR-based metabolomic approach.

Methods

Twenty-six young water polo players participated in the study voluntarily. The urine and blood samples of players were collected one week before competition (A), immediately after competition (B), and one week after competition (C). Metabolomic analysis was conducted on the urine samples. Urine routine items and biochemical indicators in blood samples were detected.

Results

Metabolomic results showed that the contents of eleven metabolites including lactic acid, acetoacetate, and succinic acid in the urine of the subjects increased and four metabolites such as dimethylamine, choline, and glucose decreased at stage B. Most metabolites at stage C had basically returned to the levels at stage A. Pyruvate metabolism, pantothenate and CoA biosynthesis, synthesis, and degradation of ketone bodies were mainly involved in the above process. Urine conventional analysis results showed that the urine pH decreased dramatically and the levels of PRO and URO significantly increased at stage B, and the three indicators had similar values between stages A and C. The other indicators did not have obvious difference among the three stages. Analysis of blood biochemical indicators showed that the levels of LDH, BUN, CK, and AST significantly increased at stage B and did not show an obvious difference between stages A and C. The results are helpful for coaches to arrange the athletes' diet reasonably and to conduct scientific training for athletes.

Prevalence and mechanisms of injuries in water polo: a systematic review

Objective

To summarise the information available in the literature on the prevalence of injuries in water polo and injury risk factors.

Methods

Protocol was registered on Open Science Framework. MEDLINE, CINAHL, Embase and SPORTDiscus databases were searched for keywords relating to water polo and injuries on 3 February 2021. References were searched for additional studies. Only original research papers in English or French were included, and studies without an injured group were excluded. A data extraction file was made based on the Cochrane Collaboration recommendations. Study quality was evaluated with the Newcastle-Ottawa scales for cohorts and a modified version for cross-sectional studies.

Results

The initial search yielded 581 articles, with 5 more added from reference lists, but only 41 remained after removing duplicates and applying inclusion/exclusion criteria. Thirty-one articles identified the head, fingers and shoulders as the most common sites of injury. Ten articles on mechanism of injury focused mainly on the shoulder, with degenerative changes, posture, scapular alignment, strength, flexibility and overhead shooting kinematics as the main injury risk factors. Publication types included cohort studies, cross-sectional studies, and one case series.

Conclusions

Most traumatic injuries affect the hands and the head from unexpected contact with the ball or opponents. Conversely, training injuries seem to affect mainly the shoulder area. Low level evidence suggests a correlation between shoulder injuries and lack of strength or flexibility as well as large volumes of overhead throwing. Further prospective research is needed to investigate risk factors for other body areas.

Hand-Held Shoulder Strength Measures Correlate With Isokinetic Dynamometry in Elite Water Polo Players

CONTEXT

Previous authors suggest that lack of strength is an important risk factor for injuries in water polo. Hand-held dynamometers have potential as a clinical tool to measure strength, but they have not been validated in water polo players.

OBJECTIVE

The purpose of this study was to estimate intertrial variability and concurrent validity of hand-held dynamometer shoulder strength measurements in elite water polo players.

METHODS

A total of 19 male and 20 female elite water polo players performed isometric external (ER) and internal (IR) rotation strength tests against a hand-held dynamometer bilaterally in supine position with the shoulder in a 90-90 position. In addition, concentric IR and ER was captured at 90 deg/s with an isokinetic dynamometer, and torque values were determined near the 90-90 position.

MAIN OUTCOME MEASURES

Spearman correlation coefficients were calculated for ER torque, IR torque, and ER/IR ratios between the devices. Two-way mixed-model intraclass correlations were used to assess intertrial variability.

RESULTS

Correlations between the devices were strong to very strong (ρ = .65-.82, P < .01) for absolute IR and ER but low for ER/IR ratios (ρ = .29, P = .07). There was less agreement at higher torque values. Intertrial variability was low with intraclass correlation values .88 to .93, P < .05.

CONCLUSIONS

These results show that hand-held dynamometers are adequate clinical alternatives to measure absolute shoulder strength in water polo players. Stronger players may require stronger evaluators to resist the player's push and obtain reliable results.

Protecting the world's finest athletes: periodic health evaluation practices of the top performing National Olympic Committees from the 2016 Rio or 2018 PyeongChang Olympic Games

AIM

To describe the periodic health evaluation (PHE) practices of the top performing National Olympic Committees (NOCs).

METHODS

We sent a survey to NOCs finishing in the top 8 for medal count at the 2016 Rio Olympic Games or 2018 PyeongChang Olympic Games. The survey included four sections: (1) PHE staff composition and roles, (2) beliefs regarding the PHE, (3) a ranking of risk factors for future injury and (4) details on the elements of the PHE.

RESULTS

All 14 NOCs with top 8 finishes at the 2016 Rio Olympic Games or 2018 PyeongChang Olympic Games completed the survey. NOCs included a median of seven staff specialties in the PHE, with physicians and physiotherapists having the highest level of involvement. There was agreement that PHEs are effective in identifying current health conditions (13/14) and that athletes should receive individualised action plans after their PHE (14/14), but less agreement (6/14) that PHEs can predict future injury. The practices of NOCs were diverse and often specific to the athlete population being tested, but always included the patient's health history, laboratory studies, cardiovascular screening and assessments of movement capacity. The top three risk factors for future injury were thought to be previous injury, age and training experience.

CONCLUSIONS

Among the top performing NOCs, the PHE is a comprehensive, multidisciplinary process aimed to identify existing conditions and provide baseline health and performance profiles in the event of future injury. Research linking PHEs to injury prevention is needed.