Racquet sports--patterns of injury presenting to a sports injury clinic

Aetiology, epidemiology and treatment of musculoskeletal injuries in badminton players: a systematic review and meta-analysis

The present study has two main goals: to conduct a systematic review of musculoskeletal injuries experienced by badminton players, and to examine the management of such injuries. Searches were conducted of the PROSPERO, PubMed, Scopus, and SPORTDiscus databases, from their inception until March 2023. The papers analysed were all based on a study population consisting of individuals aged 18 years or more, diagnosed with badminton-related injuries. The methodological quality assessments was using the Newcastle-Ottawa Scale and REVMAN. A total of 28 studies were included in the systematic review. In total, the analysis included 2435 participants. Of these athletes, 35.6% (1012) were female and 64.4% (1503) were male. By type of injury, sprains were the most commonly studied and the most prevalent, accounting for 36.06% of the sample. These were followed by muscle injuries, representing 23.86% of the total. Injuries to the joints were the least prevalent, accounting for 4.97% of the sample. Lower limb injuries accounted for 52.15% of the total. Of these, ankle injuries were the most common. Despite the generally low quality of the studies considered, the evidence suggests that musculoskeletal injuries, especially to the lower limb, most commonly affect badminton players of all levels.

Pickleball- and Paddleball-Related Injuries in the Lower Extremity: Description, Treatment Options, and Return to Play

Background Pickleball and paddleball are the fastest-growing sports in the United States. However, there are limited studies on the types of lower extremity injuries and treatment options in an outpatient clinic setting. Hypothesis/purpose This study reports the incidence rate, treatments, and return-to-play (RTP) outcomes for patients presenting to a single orthopedic outpatient center with pickleball- and paddleball-related lower extremity injuries. Study design This study is a retrospective case series, with level IV evidence. Methods A database search of our multispecialty electronic medical record (EMR) system from 2015 to 2023 identified 166 patients with outpatient pickleball- and paddleball-related lower extremity injuries. The retrospective data were reviewed for patient demographics, injury type, mechanism of injury, surgical or non-surgical treatment, and return-to-play recommendations. Results We observed that the majority of the patients with pickleball- and paddleball-related injuries in the lower extremities were over 60 years of age, with more males. Additionally, most injuries encountered were ankle sprain/strain from a twisting mechanism, which was treated non-surgically. Additionally, a significant number of patients suffered an Achilles tendon rupture (12.0%), which was treated surgically with an Achilles tendon repair (88.1%), accounting for the most common surgical treatment performed in this study. Of the 166 patients who were seen and treated, 68 (40.9%) returned to play, and 93 (56.3%) were lost to follow-up. Conclusion Most of these injuries were seen in the older population and caused by a sprain or strain due to sudden changes in direction, which were treated non-surgically. The most common surgical treatment was an Achilles tendon repair due to an Achilles tendon rupture. Although a relatively good number of patients were cleared to return to play, some patients were lost to follow-up. Meanwhile, some patients were advised to stop playing pickleball or paddleball due to the severity of their injuries. As this sport continues to rise in popularity and with the incidence rate of lower extremity injuries increasing over time, orthopedic surgeons should be aware of the types of injuries, treatment options, and outcomes, as well as ways to advise patients on prevention. Therefore, further research on the standard treatments and outcomes of pickleball- and paddleball-related injuries in the lower extremities is encouraged.

Lower-Extremity Injuries Predominate in American High School Tennis Players

Purpose

To describe injury epidemiology in U.S. adolescent tennis players between 2014 and 2018 via the High School Reporting Information Online (HS RIO) database.

Methods

The HS RIO database was queried for injury data on high school tennis players as reported by athletic trainers between 2014 and 2018. Injuries were analyzed according to athlete demographics, injury type, location, and context. Variables of interest between male and female athletes were compared using Pearson χ2 test or Fisher exact test.

Results

In total, 176 injuries in high school tennis players between 2014 and 2018 were identified in the HS RIO database. Overall, 25.6% (45/176) occurred in the ankle, 12.5% (22/176) in the knee, and 9.7% (17/176) in the wrist. The most common types of injuries were ligament sprains and muscle strains at 35.2% (62/176) and 17.6% (31/176) of injuries, respectively. Although most injuries were unrelated to contact, such as overuse and heat exertion or stroke, 28.7% (47/176) of injuries were the result of rotation around a planted foot/inversion of the foot. We found no difference in injury patterns between male and female high school tennis athletes.

Conclusions

We found no difference in injury patterns between male and female U.S. high school tennis athletes. The ankles, knees, and wrists were the most commonly injured areas in this population. The most common types of injuries were ligament sprains and muscle strains. Although many injuries were new, athletes rarely required surgery and returned to play. Finally, we found no difference in injury patterns between male and female high school tennis athletes.

Clinical Relevance

The epidemiology of injuries among high school tennis players is poorly understood. The information from this study will help us to understand these injuries and how we may be able to better prevent them.

Intelligent prediction of lower extremity loadings during badminton lunge footwork in a lab-simulated court

Introduction: Playing badminton has been reported with extensive health benefits, while main injuries were documented in the lower extremity. This study was aimed to investigate and predict the knee- and ankle-joint loadings of athletes who play badminton, with "gold standard" facilities. The axial impact acceleration from wearables would be used to predict joint moments and contact forces during sub-maximal and maximal lunge footwork. Methods: A total of 25 badminton athletes participated in this study, following a previously established protocol of motion capture and musculoskeletal modelling techniques with the integration of a wearable inertial magnetic unit (IMU). We developed a principal component analysis (PCA) statistical model to extract features in the loading parameters and a multivariate partial least square regression (PLSR) machine learning model to correlate easily collected variables, such as the stance time, approaching velocity, and peak accelerations, with knee and ankle loading parameters (moments and contact forces). Results: The key variances of joint loadings were observed from statistical principal component analysis modelling. The promising accuracy of the partial least square regression model using input parameters was observed with a prediction accuracy of 94.52%, while further sensitivity analysis found a single variable from the ankle inertial magnetic unit that could predict an acceptable range (93%) of patterns and magnitudes of the knee and ankle loadings. Conclusion: The attachment of this single inertial magnetic unit sensor could be used to record and predict loading accumulation and distribution, and placement would exhibit less influence on the motions of the lower extremity. The intelligent prediction of loading patterns and accumulation could be integrated to design training and competition schemes in badminton or other court sports in a scientific manner, thus preventing fatigue, reducing loading-accumulation-related injury, and maximizing athletic performance.

Shoulder Rotational Strength Profiles of Danish National Level Badminton Players

BACKGROUND

Increased age has been shown to be associated with weaker external rotators and stronger internal rotators of the shoulder in pitchers and tennis players. Whether this age-associated change is present in elite badminton players is unknown.

PURPOSE

To compare the internal and external rotation strength of the shoulder in adolescent and adult elite badminton players.

STUDY DESIGN

Cross-sectional.

METHODS

Thirty-one adolescent (12 females aged 16.8 ± 1.6 years and 19 males aged 17.1 ± 1.6 years) and 29 adult (10 females aged 25 ± 2.9 years and 19 males aged 26.2 ± 4.6 years) national level badminton players were tested pre-seasonally for external rotation (ER) and internal rotation (IR) isometric muscle strength bilaterally, using a hand-held dynamometer. Within-group ER to IR strength ratios were calculated (ER/IR×100%).

RESULTS

The adolescents had stronger shoulder ER than the adults on both sides (p < 0.05). The adult males tended to have stronger IR of the dominant shoulder than the adolescent males (p = 0.071). In the dominant shoulders, the strength ratios for adult females and males were 77% and 78%, respectively, while the same ratio for adolescent females and males were 85% and 99%, respectively. In the non-dominant shoulders, the ER/IR strength ratios for adult females and males were 90% and 87%, respectively, while the ratios for adolescent females and males were 116% and 102%, respectively.

CONCLUSION

This study is the first to demonstrate that in shoulder injury-free national team badminton players, adolescents have stronger shoulder ER than adults on both sides. Therefore, increased age appears to be associated with weaker shoulder ER muscles in elite badminton players.

LEVEL OF EVIDENCE

3b.

An exploratory investigation of patellofemoral joint loadings during directional lunges in badminton

Anterior knee pain is a commonly documented musculoskeletal disorder among badminton players. However, current biomechanical studies of badminton lunges mainly report kinetic profiles in the lower extremity with few investigations of in-vivo loadings. The objective of this study was to evaluate tissue loadings in the patellofemoral joint via musculoskeletal modelling and Finite Element simulation. The collected marker trajectories, ground reaction force and muscle activation data were used for musculoskeletal modelling to compute knee joint angles and quadricep muscle forces. These parameters were then set as boundary conditions and loads for a quasistatic simulation using the Abaqus Explicit solver. Simulations revealed that the left-forward (LF) and backward lunges showed greater contact pressure (14.98-29.61%) and von Mises stress (14.17-32.02%) than the right-forward and backward lunges; while, loadings in the left-backward lunge were greater than the left-forward lunge by 13-14%. Specifically, the stress in the chondral layer was greater than the contact interface, particularly in the patellar cartilage. These findings suggest that right-side dominant badminton players load higher in the right patellofemoral joint during left-side (backhand) lunges. Knowledge of these tissue loadings may provide implications for the training of badminton footwork, such as musculature development, to reduce cartilage loading accumulation, and prevent anterior knee pain.

Influence of the forehand stance on knee biomechanics: Implications for potential injury risks in tennis players

The open stance forehand has been hypothesized to be more traumatic for knee injuries in tennis than the neutral stance forehand. This study aims to compare kinematics and kinetics at the knee during three common forehand stroke stances (attacking neutral stance ANS, attacking open stance AOS, defensive open stance DOS) to determine if the open stance forehand induces higher knee loadings and to discuss its potential relationship with given injuries. Eight advanced tennis players performed eight repetitions of forehand strokes with each stance (ANS: forward run and stroke with feet parallel with the hitting direction, AOS: forward run and stroke with feet perpendicular to the hitting direction, DOS: lateral run and stroke with feet perpendicular to the hitting direction) at maximal effort. All the trials were recorded with an optoelectronic motion capture system. The flexion-extension, abduction-adduction, external-internal rotation angles, intersegmental forces and torques of the right knee were calculated. Ground reaction forces were measured with a forceplate. The DOS increases vertical GRF, maximum knee flexion and abduction angles, range of knee flexion-extension, peak of compressive, distractive and medial knee forces, peak of knee abduction and external rotation torques. Consequently, the DOS appears potentially more at risk for given knee injuries.

Prevalence and risk factors for back pain in sports: a systematic review with meta-analysis

OBJECTIVES

We aimed to determine the prevalence of low back pain (LBP) in sport, and what risk factors were associated with LBP in athletes.

DESIGN

Systematic review with meta-analysis.

DATA SOURCES

Literature searches from database inception to June 2019 in Medline, Embase, Cumulated Index to Nursing and Allied Health Literature (CINAHL), Web of Science and Scopus, supplemented by grey literature searching.

ELIGIBILITY CRITERIA

Studies evaluating prevalence of LBP in adult athletes across all sports.

RESULTS

Eighty-six studies were included (30 732, range 20-5958, participants), of which 45 were of 'high' quality. Definitions of LBP varied widely, and in 17 studies, no definition was provided. High-quality studies were pooled and the mean point prevalence across six studies was 42%; range 18%-80% (95% CI 27% to 58%, I2=97%). Lifetime prevalence across 13 studies was 63%; range 36%-88% (95% CI 51% to 74%, I2=99%). Twelve-month LBP prevalence from 22 studies was 51%; range 12%-94% (95% CI 41% to 61%, I2=98%). Comparison across sports was limited by participant numbers, study quality and methodologies, and varying LBP definitions. Risk factors for LBP included history of a previous episode with a pooled OR of 3.5; range 1.6-4.0 (95% CI 1.9 to 6.4). Statistically significant associations were reported for high training volume, periods of load increase and years of exposure to the sport.

CONCLUSION

LBP in sport is common but estimates vary. Current evidence is insufficient to identify which sports are at highest risk. A previous episode of LBP, high training volume, periods of load increase and years of exposure are common risk factors.

The epidemiology of injuries in English professional squash; A retrospective analysis between 2004 and 2015

OBJECTIVES

There have been no reported comprehensive injury reports of elite squash players during training and competition. We reviewed the reported injuries during training and competition during 2004-2015.

DESIGN

A retrospective analysis of the injury records was carried out between the periods of 2004-2015 of all athletes who were funded by England squash.

SETTING

In competition and training.

PARTICIPANTS

Elite England Squash players, 67 athletes (45 males, 22 females), with an age range of 18-35 (average 25 years).

MAIN OUTCOME MEASURES

The players' age, sex, location, region affected and description of each injury.

RESULTS

Injury data was collected from The main region of the body injured was the lower limb: 76.48%, broken down further as: ankle/heel - 20.81%; thigh - 12.69%; knee -10.83%; hip/groin - 9.48%; buttock - 7.45%; lower leg - 7.61%; and foot - 7.61%.

CONCLUSIONS

Professional squash players have a high incidence of lower limb injuries from participation in their sport. The majority of these injuries occur around the ankle and heel, and are of soft tissue in nature.

Epidemiological Patterns of Alternative Racquet-Sport Injuries in the United States, 1997-2016

Background

Racquet sports have increased in popularity over the past decade. Although research is available regarding the epidemiological characteristics of tennis injuries, little is known about the frequency and characteristics of injuries in other racquet sports.

Hypothesis

Given the increase in all racquet sport participation in the United States (US), it is hypothesized that injuries have accordingly become more frequent.

Study Design

Descriptive epidemiology study.

Methods

Using the National Electronic Injury Surveillance System database, we reviewed the numbers of badminton and squash/racquetball injuries presenting to a representative sample of US emergency departments (EDs). We used weighted estimates to extrapolate the data to the US population. Incidence estimates were compared with national participation data and stratified.

Results

A total of 4330 injuries were reported, representing an estimated 173,000 injuries presenting to US EDs from 1997 through 2016. Despite the increase in the number of players from 2006 through 2016, the annual injury rate for squash/racquetball declined significantly, including the rates for each body region assessed. No similar trend was found for badminton injuries. Within our extrapolated ED cohort, the lower extremities were the most common body region injured (37%). Strains/sprains were the most common injury type in the trunk (73%), lower extremities (65%), and upper extremities (32%), whereas lacerations were most common in the head/neck (49%). In badminton, the youngest players (age range, 5-18 years) sustained twice as many fractures (relative risk [RR], 1.96; 95% CI, 1.14-3.38) and almost 3 times as many lacerations as patients in any other age group. Similarly, the youngest squash/racquetball players were at highest risk for lacerations (RR, 1.45; 95% CI, 1.22-1.73) and head and neck injuries (RR, 1.52; 95% CI, 1.26-1.83).

Conclusion

Although declines in rates of squash/racquetball injuries were observed, the increasing popularity of badminton, squash, and racquetball necessitates further preventive measures to improve player safety, with an emphasis on the youngest players.

Comparison of Joint Loading in Badminton Lunging between Professional and Amateur Badminton Players

The knee and ankle are the two most injured joints associated with the sport of badminton. This study evaluates biomechanical factors between professional and amateur badminton players using an injury mechanism model. The aim of this study was to investigate the kinematic motion and kinetic loading differences of the right knee and ankle while performing a maximal right lunge. Amateur players exhibited greater ankle range of motion (p < 0.05, r = 0.89) and inversion joint moment (p < 0.05, r = 0.54) in the frontal plane as well as greater internal joint rotation moment (p < 0.05, r = 0.28) in the horizontal plane. In contrast, professional badminton players presented a greater knee joint moment in the sagittal (p < 0.05, r = 0.59) and frontal (p < 0.05, r = 0.37) planes, which may be associated with increased knee ligamentous injury risk. To avoid injury, the players need to forcefully extend the knee with internal rotation, strengthen the muscles around the ankle ligament, and maximise joint coordination during training. The injuries recorded and the forces responsible for the injuries seem to have developed during training activity. Training programmes and injury prevention strategies for badminton players should account for these findings to reduce potential injury to the ankle and knee.

Prevalence of Musculoskeletal Conditions in Tennis-Teaching Professionals

Background:

Tennis-teaching professionals represent a significant proportion of all avid tennis players worldwide, with 15,000 belonging to the largest professional organization, the United States Professional Tennis Association (USPTA). However, there is no epidemiologic study to date reporting the prevalence of musculoskeletal conditions in these tennis-teaching professionals.

Purpose:

To investigate the prevalence of musculoskeletal conditions in tennis-teaching professionals following the International Tennis Federation’s (ITF) guidelines for epidemiologic studies.

Study Design:

Descriptive epidemiology study.

Methods:

Electronic surveys were distributed to 13,500 American members of the USPTA. The prevalence of musculoskeletal conditions was calculated.

Results:

A total of 1176 USPTA members completed the survey. Most participants reported teaching more than 5 days per week and more than 2 hours per day. The prevalence of musculoskeletal injury secondary to teaching tennis was 42%. The most affected area was the lower extremities (43% of all injuries) followed by the upper extremities (37%). The most commonly injured structures were muscles or tendons (36% of all injuries) and joints or ligaments (28%). The majority of injuries did not cause participants to miss more than 24 hours of teaching (57%).

Conclusion:

This is the first epidemiologic study on the occupational risk of musculoskeletal injuries and conditions in tennis-teaching professionals. Tennis-teaching professionals have a significant risk of musculoskeletal injuries or conditions related to their occupation. The prevalence of injury is consistent with previously published studies of injury prevalence among other tennis-playing populations. The proportions of upper and lower extremity injuries were fairly equitable.

The influence of tennis court surfaces on player perceptions and biomechanical response

This study aimed to examine player perceptions and biomechanical responses to tennis surfaces and to evaluate the influence of prior clay court experience. Two groups with different clay experiences (experience group, n = 5 and low-experience group, n = 5) performed a 180° turning movement. Three-dimensional ankle and knee movements (50 Hz), plantar pressure of the turning step (100 Hz) and perception data (visual analogue scale questionnaire) were collected for two tennis courts (acrylic and clay). Greater initial knee flexion (acrylic 20. 8 ± 11.2° and clay 32.5 ± 9.4°) and a more upright position were reported on the clay compared to the acrylic court (P < 0.05). This suggests adaptations to increase player stability on clay. Greater hallux pressures and lower midfoot pressures were observed on the clay court, allowing for sliding whilst providing grip at the forefoot. Players with prior clay court experience exhibited later peak knee flexion compared to those with low experience. All participants perceived the differences in surface properties between courts and thus responded appropriately to these differences. The level of previous clay court experience did not influence players' perceptions of the surfaces; however, those with greater clay court experience may reduce injury risk as a result of reduced loading through later peak knee flexion.

Association between rotation-related impairments and activity type in people with and without low back pain

OBJECTIVE

To determine whether people with low back pain (LBP) who regularly participated in a rotation-related activity displayed more rotation-related impairments than people without LBP who did and did not participate in the activity.

DESIGN

Secondary analysis of data from a case-control study.

SETTING

Musculoskeletal analysis laboratory at an academic medical center.

PARTICIPANTS

A convenience sample of participants with LBP (n=55) who participated in a rotation-related sport, back-healthy controls (n=26) who participated in a rotation-related sport, and back-healthy controls (n=42) who did not participate in a rotation-related sport. Participants were matched based on age, sex, and activity level.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The total number of rotation-related impairments and asymmetrical rotation-related impairments identified during a standardized clinical examination.

RESULTS

Compared with the back-healthy controls who do not play a rotation-related sport group, both the LBP and back-healthy controls who play a rotation-related sport groups displayed significantly more (1) rotation-related impairments (LBP, P<.001; back-healthy controls who play a rotation-related sport, P=.015), (2) asymmetrical rotation-related impairments (LBP, P=.006; back-healthy controls who play a rotation-related sport, P=.020), and (3) rotation-related impairments with trunk movement tests (LBP, P=.002; back-healthy controls who play a rotation-related sport, P<.001). The LBP group had significantly more rotation-related impairments with extremity movement tests than both of the back-healthy groups (back-healthy controls who play a rotation-related sport, P=.011; back-healthy controls who do not play a rotation-related sport, P<.001).

CONCLUSIONS

The LBP and back-healthy controls who play a rotation-related sport groups demonstrated a similar number of total rotation-related impairments and asymmetrical rotation-related impairments, and these numbers were greater than those of the back-healthy controls who do not play a rotation-related sport group. Compared with people without LBP, people with LBP displayed more rotation-related impairments when moving an extremity. These findings suggest that impairments associated with extremity movements may be associated with having an LBP condition.

MRI findings in the lumbar spines of asymptomatic elite junior tennis players

OBJECTIVE

To evaluate the MRI findings in the lumbar spines of asymptomatic elite junior tennis players.

MATERIALS AND METHODS

The lumbar spine MRI studies of 98 asymptomatic junior elite tennis players (51 male, 47 female) with a mean age of 18 years (age range 11.2-26.3 years; standard deviation 3.1) was reviewed by two consultant musculoskeletal radiologists using consensus opinion. Images were assessed using accepted classification systems.

RESULTS

Four players (4%) had no abnormality. Facet joint arthropathy occurred in 89.7% of the players, being mild in 84.5% of cases. There were 41 synovial cysts in 22.4% of the cohort all occurring in the presence of facet arthropathy. Disc degeneration was noted in 62.2 % of players, being mild in 76.2% of those affected. Disc herniation was noted in 30.6% of players, with 86.1% of these being broad based and 13.9% being focal. There was nerve root compression in 2%. There were 41 pars interarticularis abnormalities in 29.6% of patients, 63.4% of these being grades 1-3. There was grade 1 spondylolisthesis in 5.1% of players. The prevalence of facet joint arthropathy, disc degeneration, disc herniation and pars interarticularis fracture was lower in female players than in male and lower in the under 16-year-olds compared with the over 20-year-olds.

CONCLUSION

There is a significant amount of underlying pathology that would normally go undetected in this group of asymptomatic elite athletes. Whilst these findings cannot be detected clinically, their relevance is in facilitating appropriate prehabilitation to prevent loss of playing time and potentially career-ending injuries.

Upper limb joint kinetic analysis during tennis serve: Assessment of competitive level on efficiency and injury risks

The aim of this work was to compare the joint kinetics and stroke production efficiency for the shoulder, elbow, and wrist during the serve between professionals and advanced tennis players and to discuss their potential relationship with given overuse injuries. Eleven professional and seven advanced tennis players were studied with an optoelectronic motion analysis system while performing serves. Normalized peak kinetic values of the shoulder, elbow, and wrist joints were calculated using inverse dynamics. To measure serve efficiency, all normalized peak kinetic values were divided by ball velocity. t-tests were used to determine significant differences between the resultant joint kinetics and efficiency values in both groups (advanced vs professional). Shoulder inferior force, shoulder anterior force, shoulder horizontal abduction torque, and elbow medial force were significantly higher in advanced players. Professional players were more efficient than advanced players, as they maximize ball velocity with lower joint kinetics. Since advanced players are subjected to higher joint kinetics, the results suggest that they appeared more susceptible to high risk of shoulder and elbow injuries than professionals, especially during the cocking and deceleration phases of the serve.

Associations between abnormal ultrasound color Doppler measures and tendon pain symptoms in badminton players during a season: a prospective cohort study

BACKGROUND

Color Doppler ultrasound is widely used to examine intratendinous flow in individuals with overuse tendon problems, but the association between color Doppler and pain is still unclear.

HYPOTHESIS

Intratendinous flow is present and associated with pain in badminton players, and intratendinous flow and pain increase during a badminton season.

STUDY DESIGN

Cohort study (prognosis); Level of evidence, 2.

METHODS

Ninety-five semiprofessional badminton players were included in the study at a tournament at the start of the badminton season. All players were interviewed regarding pain. The anterior knee tendons and Achilles tendons were studied. Each tendon was scored using a quantitative grading system (grades 0-5) and a qualitative scoring system (color fraction) using color Doppler ultrasound. Eight months later, 86 of the players (91%) were retested by the same investigators during an equivalent badminton tournament (including 1032 tendon regions; 86 players with 4 tendons each with 3 regions), thus forming the study group.

RESULTS

At the start of the season, 24 players (28%) experienced pain in 37 tendons (11%), and at the end of the season, 31 players (36%) experienced pain in 51 tendons (15%), which was a statistically significant increase (P = .0002). Abnormal flow was found in 230 tendon regions in 71 players (83%) at the start of the season compared with 78 tendon regions in 41 players (48%) at the follow-up. The decrease in abnormal flow was statistically significant (P < .0001). Of the 37 painful tendons at the start of the season, 25 had abnormal flow (68%). In contrast, 131 tendons (85%) with abnormal flow at the start of the season were pain free. At the end of the season, 18 of the 51 painful tendons (35%) had abnormal flow. Ninety-six of the 131 pain-free tendons (73%) with abnormal flow at the start of the season were normalized (no pain and normal flow) at the end of the season.

CONCLUSION

It was not possible to verify any association between intratendinous flow and pain at the start of the season or at the follow-up (end of the season). Intratendinous flow at the start of the season could not predict symptomatic outcome at the end of the season. The decrease in Doppler flow during the season might suggest that intratendinous flow could be part of a physiological adaptive response to loading and that intratendinous flow as previously believed is not always a sign of pathological changes.

Evidence of accumulated stress in Achilles and anterior knee tendons in elite badminton players

Tendon-related injuries are a major problem, but the aetiology of tendinopathies is unknown. In tendinopathies as well as during unaccustomed loading, intra-tendinous flow can be detected indicating that extensive loading can provoke intra-tendinous flow. The aim of present study is to evaluate the vascular response as indicated by colour Doppler (CD) activity in both the Achilles and patella tendon after loading during high-level badminton matches. The Achilles tendon was subdivided into a mid-tendon, pre-insertional, and insertional region and the anterior knee tendons into a quadriceps-, patella- and tuberositas region. Intra-tendinous flow was measured using both a semi-quantitative grading system (CD grading) and a quantitative scoring system (CF) on colour Doppler. Intra-tendinous flow in the Achilles and anterior knee tendons was examined in fourteen single players before tournament and after 1st and 2nd match, respectively on both the dominant and non-dominant side. All players had abnormal intra-tendinous flow (Colour Doppler ≥ grade 2) in at least one tendon in at least one scan during the tournament. At baseline, only two of the 14 players had normal flow in all the tendons examined. After 1st match, tendencies to higher intra-tendinous flow were observed in both the dominant patella tendon and non-dominant quadriceps tendon (P-values n.s.). After 2nd match, intra-tendinous flow was significant increased in the dominant patella tendon (P = 0.009). In all other locations, there was a trend towards a stepwise increase in intra-tendinous flow. The preliminary results indicate that high amount of intra-tendinous flow was found in elite badminton players at baseline and was increased after repetitive loading, especially in the patella tendon (dominant leg). The colour Doppler measurement can be used to determine changes in intra-tendinous flow after repetitive loading.

Relationship between the hip and low back pain in athletes who participate in rotation-related sports

CONTEXT

Hip function has been proposed to be related to low back pain (LBP) because of the anatomical proximity of the hip and lumbopelvic region. To date, findings have been inconclusive, possibly because the samples studied were heterogeneous. Sub-grouping samples based on characteristics such as activity demand, LBP classification, and sex might clarify research findings.

OBJECTIVE

To describe and summarize studies that examine 3 factors proposed to be important to the study of the hip-LBP relationship.

DESIGN

Review of cross-sectional studies.

SETTING

Academic health-care center and research laboratory.

SUBJECTS

3 groups: athletes with a history of LBP who regularly participate in rotation-related sports, athletes without a history of LBP who are active but do not regularly participate in rotation-related sports, and athletes without a history of LBP who participate in rotation-related sports.

MAIN OUTCOME

Hip range of motion and hip-lumbopelvic region coordination.

MEASURES

Hip range of motion was measured with an inclinometer. Coordination was examined based on kinematics obtained with a 3-dimensional motion-capture system.

RESULT

Differences among groups were found based on activity demand, LBP classification, and sex.

CONCLUSION

When assessing athletes with and without LBP, characteristics such as activity demand, LBP classification, and sex should be considered.

Bilateral ground reaction forces and joint moments for lateral sidestepping and crossover stepping tasks

Racquet sports have high levels of joint injuries suggesting the joint loads during play may be excessive. Sports such as badminton employ lateral sidestepping (SS) and crossover stepping (XS) movements which so far have not been described in terms of biomechanics. This study examined bilateral ground reaction forces and three dimensional joint kinetics for both these gaits in order to determine the demands of the movements on the leading and trailing limb and predict the contribution of these movements to the occurrence of overuse injury of the lower limbs. A force platform and motion-analysis system were used to record ground reaction forces and track marker trajectories of 9 experienced male badminton players performing lateral SS, XS and forward running tasks at a controlled speed of 3 m·s(-1) using their normal technique. Ground reaction force and kinetic data for the hip, knee and ankle were analyzed, averaged across the group and the biomechanical variables compared. In all cases the ground reaction forces and joint moments were less than those experienced during moderate running suggesting that in normal play SS and XS gaits do not lead to high forces that could contribute to increased injury risk. Ground reaction forces during SS and XS do not appear to contribute to the development of overuse injury. The distinct roles of the leading and trailing limb, acting as a generator of vertical force and shock absorber respectively, during the SS and XS may however contribute to the development of muscular imbalances which may ultimately contribute to the development of overuse injury. However it is still possible that faulty use of these gaits might lead to high loads and this should be the subject of future work. Key pointsGround reaction forces and joint moments during lateral stepping are smaller in magnitude than those experienced during moderate running.Force exposure in SS and XS gaits in normal play does not appear to contribute to the development of overuse injuryThe leading and trailing limbs perform distinct roles, acting as a generator of vertical force and shock absorber respectively.This distinct contribution may contribute to the development of muscular imbalances which may ultimately contribute to the development of overuse injury.

Relationship between hip strength and frontal plane posture of the knee during a forward lunge

OBJECTIVE

Excessive frontal plane knee movement during forward lunge movements might be associated with the occurrence of knee injuries in tennis. Here, we attempt to determine whether hip muscle strength is related to the frontal plane motion of the knee during a functional lunge movement.

DESIGN

A correlational study.

PARTICIPANTS

A total of 84 healthy subjects (76 men, 8 women), with no history of knee or lower leg complaints.

INTERVENTIONS

Muscle strength of six hip muscle groups was measured using a handheld dynamometer. Subjects were videotaped during a forward lunge and peak knee valgus or varus angles were determined using a digital video analysis software program.

MAIN OUTCOME MEASUREMENTS

A correlation was examined between hip muscle strength and the amount of frontal plane movement of the knee during a forward lunge.

RESULTS

There were no significant differences in hip muscle strength between the valgus group and the varus group during the forward lunge movement. No significant correlation was found between the strength of the assessed hip muscles and the amount of movement into valgus/varus. In the varus group a moderate positive correlation was found between the External Rotation/Internal Rotation force ratio and the amount of knee varus during the forward lunge movement (r = 0.31, p = 0.03).

CONCLUSIONS

The findings suggest that in healthy subjects hip muscle strength is not correlated to the amount of valgus/varus movement of the knee during a forward lunge. This suggests that other factors (eg, proprioception, core hip stability) might be more important in controlling knee movement during this tennis-specific movement.

Epidemiology of Injuries in Hong Kong Elite Badminton Athletes

This study retrospectively reviewed the injury epidemiology on 44 Hong Kong elite badminton players in 2003. Team training records were reviewed to retrieve the training and competition hours, while the medical records from the physiotherapy department were reviewed to obtain information regarding injuries. A total of 253 injuries (128 recurrent and 125 new injuries) were recorded, which accounted for an overall incidence rate of 5.04 per 1,000 player hours. Elite senior athletes had a higher incidence rate of recurrent injuries, while elite junior and potential athletes had a higher incidence rate of new injuries. A total of 1,219 visits (4.82 per athlete) to the physiotherapy department were recorded, which cost HK$487,600 (HK$1,928 per injury). Most new injuries were strain (80 injuries), and the most frequently injured body sites were the back (17 injuries), the shoulder (15 injuries), the thigh (15 injuries), and the knee (15 injuries). One-sided exact test showed that a previous injury experience significantly associated with the occurrence of new injury.

A systematic review on ankle injury and ankle sprain in sports

This article systematically reviews epidemiological studies on sports injury from 1977 to 2005 in which ankle injury was included. A total of 227 studies reporting injury pattern in 70 sports from 38 countries were included. A total of 201,600 patients were included, with 32,509 ankle injuries. Ankle injury information was available from 14,098 patients, with 11 847 ankle sprains. Results show that the ankle was the most common injured body site in 24 of 70 included sports, especially in aeroball, wall climbing, indoor volleyball, mountaineering, netball and field events in track and field. Ankle sprain was the major ankle injury in 33 of 43 sports, especially in Australian football, field hockey, handball, orienteering, scooter and squash. In sports injuries throughout the countries studied, the ankle was the second most common injured body site after the knee, and ankle sprain was the most common type of ankle injury. The incidence of ankle injury and ankle sprain was high in court games and team sports, such as rugby, soccer, volleyball, handball and basketball. This systematic review provides a summary of the epidemiology of ankle injury in sports.

A systematic review on ankle injury and ankle sprain in sports

This article systematically reviews epidemiological studies on sports injury from 1977 to 2005 in which ankle injury was included. A total of 227 studies reporting injury pattern in 70 sports from 38 countries were included. A total of 201,600 patients were included, with 32,509 ankle injuries. Ankle injury information was available from 14,098 patients, with 11 847 ankle sprains. Results show that the ankle was the most common injured body site in 24 of 70 included sports, especially in aeroball, wall climbing, indoor volleyball, mountaineering, netball and field events in track and field. Ankle sprain was the major ankle injury in 33 of 43 sports, especially in Australian football, field hockey, handball, orienteering, scooter and squash. In sports injuries throughout the countries studied, the ankle was the second most common injured body site after the knee, and ankle sprain was the most common type of ankle injury. The incidence of ankle injury and ankle sprain was high in court games and team sports, such as rugby, soccer, volleyball, handball and basketball. This systematic review provides a summary of the epidemiology of ankle injury in sports.

Ultrasonographic investigation of the Achilles tendon in elite badminton players using color Doppler

BACKGROUND

The most frequent injuries in badminton players are in the lower extremities, especially in the Achilles tendon.

HYPOTHESIS

The game of badminton may be related to abnormal intratendinous flow in the Achilles tendon as detected by color Doppler ultrasound. To a certain extent, this blood flow might be physiological, especially when examined after match.

STUDY DESIGN

Cohort study (prevalence); Level of evidence, 3.

METHODS

Seventy-two elite badminton players were interviewed regarding Achilles tendon pain (achillodynia) in the preceding 3 years. Color Doppler was used to examine the tendons of 64 players before their matches and 46 players after their matches. Intratendinous color Doppler flow was graded from 0 to 4. The Achilles tendon was divided into dominant (eg, right side for right-handed players and vice versa) and nondominant side and classified as midtendon, preinsertional, and calcaneal areas.

RESULTS

Of 72 players, 26 had experienced achillodynia in 34 tendons, 18 on the dominant side and 16 on the nondominant side. In 62% of the players with achillodynia, the problems had begun slowly, and the median duration of symptoms was 4 months (range, 0-36 months). Thirty-five percent had ongoing pain in their tendons for a median duration of 12 months (range, 0-12 months). Achillodynia was not associated with the self-reported training load or with sex, age, weight, singles or doubles players, or racket side. Forty-six players were scanned before and after match. At baseline, color Doppler flow was present in the majority of players, and only 7 (16%) players had no color Doppler flow in either tendon. After match, all players had some color Doppler flow in 1 or both tendons. Achillodynia and color Doppler flow were related in the nondominant Achilles tendon (chi-square, P = .008). The grades of Doppler flow also increased significantly after match in the preinsertional area in both the nondominant (P = .0002) and dominant (P = .005) side tendons.

CONCLUSION

A large proportion of the players had experienced achillodynia and habitually played with a degree of pain that demanded medication. The self-reported pain was associated with increased intratendinous color Doppler flow in the nondominant Achilles tendon. Doppler flow was found in most players before and in all players after the match and therefore may in part be a physiological response to activity.

Musculoskeletal injuries in tennis

Tennis is popular in the United States, with millions participating in the sport. Unlike many other sports, young, middle-aged, and elderly persons are actively playing tennis. Most injuries that are seen are secondary to overuse. Faulty stroke mechanics are often involved in the development of specific injuries seen in tennis players. Fortunately, most injuries respond to conservative treatment and do not require surgery. Most players are able to return to their previous level of activity after appropriate treatment.

Shoulder pain -- a common problem in world-class badminton players

Badminton is a sport that requires a lot of over-shoulder motion, with the shoulder in abduction/external rotation. This questionnaire study on 188 international top-level badminton players during the World Mixed Team Championships showed that previous or present shoulder pain on the dominant side was reported by 52% of the players. Previous shoulder pain was reported by 37% of the players and on-going shoulder pain by 20% of the players. There were no significant differences in the prevalence of shoulder pain between men and women. The majority of the shoulder pain had started gradually. The pain was usually associated with shoulder activity, and stiffness was a common, associated symptom. Furthermore, the shoulder pain was associated with consequences such as sleeping disturbances, changes in training and competition habits, and it also affected activities of daily living. The majority of the players had sought medical advice and had been given different kinds of treatment. The study showed that shoulder pain is a common and significant problem in world-class badminton players, and the consequences are most likely of importance for their training and playing capacity.

Decreased shoulder function and pain common in recreational badminton players

The aim of this study was to describe the prevalence and consequences of painful conditions in the shoulder region in recreational badminton players. A questionnaire study was performed on 99 players, of whom 57 were also assessed with Constant score. Previous or present pain in the dominant shoulder was reported by 52% of the players. Sixteen percent of the players had on-going shoulder pain associated with badminton play. A majority of these players reported that their training habits were affected by the pain. Total Constant score was lower in the painful shoulders. Furthermore, range of active pain-free shoulder abduction was decreased. However, isometric shoulder strength test showed no differences when compared with pain-free shoulders. Even though the pain caused functional problems, the players were still playing with on-going symptoms. The diagnoses were mostly unknown, although history and clinical tests indicate problems resembling subacromial impingement.

Tennis injuries: occurrence, aetiology, and prevention

A systematic search of published reports was carried out in three electronic databases from 1966 on to identify relevant articles relating to tennis injuries. There were 39 case reports, 49 laboratory studies, 28 descriptive epidemiological studies, and three analytical epidemiological studies. The principal findings of the review were: first, there is a great variation in the reported incidence of tennis injuries; second, most injuries occur in the lower extremities, followed by the upper extremities and then the trunk; third, there have been very few longitudinal cohort studies that investigated the association between risk factors and the occurrence of tennis injuries (odds ratios, risk ratios, hazard ratios); and fourth, there were no randomised controlled trials investigating injury prevention measures in tennis. More methodologically sound studies are needed for a better understanding of risk factors, in order to design useful strategies to prevent tennis injuries.

Trunk rotation-related impairments in people with low back pain who participated in 2 different types of leisure activities: a secondary analysis

STUDY DESIGN

Cross-sectional, secondary analysis.

OBJECTIVES

To examine whether there were differences in the numbers and types of impairments on examination between 2 groups of people with low back pain (LBP), those who participated in symmetric leisure activities and those who participated in asymmetric leisure activities.

BACKGROUND

It has been proposed that people who repeatedly perform an activity that involves trunk movements and alignments in the same direction will develop strategies that are generalized to many activities. The repeated use of these strategies is proposed to contribute to impairments identifiable on examination and to LBP.

METHODS AND MEASURES

Forty males and 40 females (mean +/- SD age, 41.4 +/- 13.9 years) with LBP who reported participation in either a symmetric or an asymmetric leisure activity participated in a standardized examination. Responses from 10 trunk-rotation-related impairment tests were analyzed using the Mann-Whitney U and chi-square statistics.

RESULTS

Thirty people participated in asymmetric leisure activities and 50 people participated in symmetric leisure activities. The total number of rotation-related impairments was different for the 2 groups (U = 1112, P < .01). The asymmetric group displayed more total rotation-related impairments (median, 4.0; range, 7) than the symmetric group (median, 2.0; range, 6). A greater percentage of the asymmetric group displayed more impairments on 5 out of 10 individual tests, as compared to the symmetric group ( < or = .05 for all comparisons).

CONCLUSIONS

Our results provide preliminary data to suggest that trunk-rotation-related impairments, identified on examination, may be related to the general type of movements and alignments used repeatedly by patients with LBP.

The efficacy of splinting for lateral epicondylitis: a systematic review

To determine the efficacy of using splinting as a treatment for lateral epicondylitis (LE), a systematic review of the literature was conducted on Medline, Cumulative Index to Nursing and Allied Health Literature (CINAHL), EMBASE, PEDro, and Cochrane databases using pertinent key words and phrases. Hand searches of article references were also used to ensure that as many relevant articles as possible were identified. Searches were limited to articles published in English. Articles that did not involve splinting (or terminology derivative thereof) as treatment intervention for LE were excluded. From 98 potential articles, 58 were considered strong inclusion candidates. These articles were copied and further triaged according to predefined criteria, resulting in 22 articles that were numbered randomly and blinded. Three reviewers appraised these articles, eliminating 11 of the articles because they did not meet essential criteria of randomization, control group, and/or inferential statistical analysis. Using MacDermid quality scores, the 11 remaining articles were rated by three reviewers. Consensus between the three reviewers was achieved for all quality scores for all 11 articles included in the review. Adjusted quality scores ranged from 44.5 to 16.5 with a mean of 26.3 points. For accurate comparison and consistency of terminology, splints described in the included articles were first classified according to the ASHT Splint Classification, expanded and refined version, and next according to their inherent material properties. Six splints in five classification categories were identified. Discussion of the results from the 11 included studies was organized according to splint category and further separated into strength, pain, and load applied sections. This review identified one Sackett level 1b study and ten Sackett level 2b studies that offer early positive, but not conclusive, support for the effectiveness of splinting lateral epicondylitis. None of the reviewed studies received a perfect quality score, and the wide range of quality scores attests to the fact that considerable improvement of future studies is essential.

Science and the major racket sports: a review

The major racket sports include badminton, squash, table tennis and tennis. The growth of sports science and the commercialization of racket sports in recent years have focused attention on improved performance and this has led to a more detailed study and understanding of all aspects of racket sports. The aim here, therefore, is to review recent developments of the application of science to racket sports. The scientific disciplines of sports physiology and nutrition, notational analysis, sports biomechanics, sports medicine, sports engineering, sports psychology and motor skills are briefly considered in turn. It is evident from these reviews that a great deal of scientific endeavour has been applied to racket sports, but this is variable across both the racket sports and the scientific disciplines. A scientific approach has helped to: implement training programmes to improve players' fitness; guide players in nutritional and psychological preparation for play; inform players of the strategy and tactics used by themselves and their opponents; provide insight into the technical performance of skills; understand the effect of equipment on play; and accelerate the recovery from racket-arm injuries. Racket sports have also posed a unique challenge to scientists and have provided vehicles for developing scientific methodology. Racket sports provide a good model for investigating the interplay between aerobic and anaerobic metabolism and the effect of nutrition, heat and fatigue on performance. They have driven the development of mathematical solutions for multi-segment interactions within the racket arm during the performance of shots, which have contributed to our understanding of the mechanisms of both performance and injury. They have provided a unique challenge to sports engineers in relation to equipment performance and interaction with the player. Racket sports have encouraged developments in notational analysis both in terms of analytical procedures and the conceptualization of strategy and tactics. Racket sports have provided a vehicle for investigating fast interceptive actions, hand-eye coordination and perception-action coupling in the field of motor control. In conclusion, science has contributed considerably to our knowledge and understanding of racket sports, and racket sports have contributed to science by providing unique challenges to researchers.

Functional deficits in athletes with a history of low back pain: a pilot study

OBJECTIVE

To evaluate whether athletes with a history of low back pain (LBP) would, on average, perform slower on a timed 20-m shuttle run as compared with a normal athletic population.

DESIGN

A timed shuttle run to evaluate residual functional limitations in college athletes with resolved LBP.

SETTING

National College Athletic Association (NCAA) division I college.

PARTICIPANTS

NCAA division I athletes (161 men, 50 women).

INTERVENTION

A timed 20-m shuttle run.

MAIN OUTCOME MEASURE

Each athlete was timed in a divided 20 m (66 ft) run in which 2 taped lines were positioned 6.7 m (22 ft) apart.

RESULTS

Of 211 athletes evaluated, 27 had been treated for LBP during the previous year. Currently asymptomatic athletes with a recent history of LBP were slower (6.3s vs 5.8s) during performance of the timed 20-m shuttle run than athletes without LBP (P=.0002).

CONCLUSIONS

Athletes with resolved LBP were slower than a matched group of normal athletes without LBP in the timed 20-m shuttle run. Further research is needed to support these findings and to understand fully the influence of the kinetic chain and the effects of both gender and sport on the observed findings.

Management of the athlete with low back pain

The evaluation of an athlete with LBP using the classification system proposed by Delitto et al has been outlined. For outpatient orthopaedic practice, evidence in the literature is available documenting the reliability and the effectiveness of treatment guided by TBC. This classification system provides framework for the clinician to evaluate athletes with LBP because it investigates the presence of serious pathology, considers the severity of the disease process, and provides matched treatment based on the athlete's clinical presentation. When treating athletes with episodes of acute LBP, pain modulation and return to daily function are the primary treatment goals. When treating athletes with episodes of chronic LBP, return to sport and prevention of recurrence are the primary treatment goals.

Epidemiology of back pain in the athlete

Back pain and injuries are common complaints of athletes. The nature of the sport involved with the specific stresses that it places on the athlete's spine may play a role in the injuries incurred. These injuries may limit an athlete's function and hinder performance; however, the majority of these insults are self-limiting and respond well to conservative measures. Based on the epidemiologic data, it appears that possibly the single most important step in reducing the back pain experienced by athletes would involve the performance of a structured back-strengthening program. Such a plan might reduce the most common diagnostic entities encountered by the athlete with back pain.

Hip muscle imbalance and low back pain in athletes: influence of core strengthening

PURPOSE

The influence of a core-strengthening program on low back pain (LBP) occurrence and hip strength differences were studied in NCAA Division I collegiate athletes.

METHODS

In 1998, 1999, and 2000, hip strength was measured during preparticipation physical examinations and occurrence of LBP was monitored throughout the year. Following the 1999-2000 preparticipation physicals, all athletes began participation in a structured core-strengthening program, which emphasized abdominal, paraspinal, and hip extensor strengthening. Incidence of LBP and the relationship with hip muscle imbalance were compared between consecutive academic years.

RESULTS

After incorporation of core strengthening, there was no statistically significant change in LBP occurrence. Side-to-side extensor strength between athletes participating in both the 1998-1999 and 1999-2000 physicals were no different. After core strengthening, the right hip extensor was, on average, stronger than that of the left hip extensor (P = 0.0001). More specific gender differences were noted after core strengthening. Using logistic regression, female athletes with weaker left hip abductors had a more significant probability of requiring treatment for LBP (P = 0.009)

CONCLUSION

The impact of core strengthening on collegiate athletes has not been previously examined. These results indicated no significant advantage of core strengthening in reducing LBP occurrence, though this may be more a reflection of the small numbers of subjects who actually required treatment. The core program, however, seems to have had a role in modifying hip extensor strength balance. The association between hip strength and future LBP occurrence, observed only in females, may indicate the need for more gender-specific core programs. The need for a larger scale study to examine the impact of core strengthening in collegiate athletes is demonstrated.