Protocol and validity testing of femoroacetabular posterior translation with dynamic hip ultrasonography

OBJECTIVE

To describe femoroacetabular posterior translation (FAPT) using dynamic hip ultrasonography (DHUS), and to determine the inter- and intra-rater reliability of hip ultrasound measurements of FAPT.

MATERIALS AND METHODS

The study design was a feasibility study of 13 healthy young adults (26 hips) using test-retest analysis. The data was collected prospectively over a 2-week time period. Three DHUS measurements (posterior neutral (PN), flexion, adduction, and internal rotation (PFADIR), and stand and load (PStand) were measured by four independent raters (2 senior who divided the cohort, 1 intermediate, 1 junior) at two time points for bilateral hips of each participant. Reliability was assessed by calculating the intraclass correlation coefficient (ICC) along with 95% confidence intervals (CIs) for each rater and across all raters.

RESULTS

A total of 468 US scans were completed. The mean age of the cohort was 25.7 years (SD 5.1 years) and 54% were female. The inter-rater reliability was excellent for PFADIR (ICC 0.85 95% CI 0.76-0.91), good for PN (ICC 0.69 95% CI 0.5-0.81), and good for PStand (ICC 0.72 95% CI 0.55-0.83). The intra-rater reliability for all raters was good for PFADIR (ICC 0.60 95% CI 0.44-0.73), fair for PN (ICC 0.42 95% CI 0.21-0.59), and fair for PStand (ICC 0.42 95% CI 0.22-0.59).

CONCLUSION

This is the first study to present a protocol using dynamic ultrasonography to measure FAPT. DHUS measure for FAPT was shown to be reliable across raters with varying levels of ultrasound experience.

Biomechanical changes identified during a marathon race among high-school aged runners

BACKGROUND

Despite the increasing popularity of endurance running competitions among adolescent runners, there is currently limited information regarding expected biomechanical changes across the duration of a long-distance running event, and the relationship between young runners' biomechanics and running performance. Wearable technology offers an ecological means to continuously assess runners' biomechanical data during outdoor running competitions.

RESEARCH QUESTION

Do adolescent athletes adopt changes in sensor-derived biomechanics throughout a marathon race, and are there relationships between race performance and biomechanical features among young marathoners?

METHODS

Fourteen high-school aged runners (9 M, 5 F; age: 16 ± 1 years, height: 170.8 ± 7.5 cm; mass: 63.6 ± 9.4 kg) wore lace-mounted sensors to record step-by-step biomechanics during a marathon race. Official race segment completion times were extracted across 5 race segments (5-K, 15-K, Half Marathon [21.1-K], 35-K, Marathon [42.2-K]). Within-participant repeated measures of covariance (pace) were conducted to assess changes in biomechanics across the race, with Bonferroni post-hoc comparisons. Pearson's r correlations were performed to assess the relationship between race finish times and biomechanics.

RESULTS

Pace was significantly slower (p-range: 0.002-0.005), contact times significantly longer, and stride lengths significantly shorter in the final segment compared to middle segments (p-range: 0.003-0.004). The rate of shock accumulation was significantly higher in the final race segment compared to the first three segments (p-range: 0.001-0.002). Moderate relationships existed between finish times and pace (r = -0.63), stride length (r = -0.62), and contact time (r = 0.51).

SIGNIFICANCE

Adolescent runners altered their gait patterns in the final marathon segment compared to earlier segments. Spatiotemporal measures were moderately correlated with race finish times, suggesting a link between faster run pace, increased stride lengths, and reduced contact time for improved running performance during an endurance race.

Clinical assessment, treatment, and referral trends for adolescent runners seeking care at an injured runners' clinic

PURPOSE

Over a 10-year time frame, this study aimed to evaluate diagnosis, treatment, and referral trends for adolescent runners seeking care for running-related injuries (RRIs) at a clinic that specializes in running medicine.

METHODS

This study was a retrospective chart review of 392 adolescent runners (2,326 encounters) who sought care for RRIs between the years 2011 and 2021. Descriptive statistics were used to summarize clinical assessments, referrals, assistive devices, and medications prescribed or administered overall and by injury type. Chi-square analyses were used to compare proportions of services rendered across the 10-year time frame.

RESULTS

Patients most frequently received manual evaluations or special tests during clinic visits. Most visits resulted in at least one referral (91%), primarily for physical therapy or gait-training. Assistive devices and medications/supplements were offered at only 18% of patient visits. The majority of assessments (X2 = 69.7, p = 0.002), treatments (X2: 23.6-43.8, p: <  0.001-0.003), and referrals (X2 = 132, p <  0.001) were for shin injuries. Larger proportions of nutrition assessments (X2 = 40.7, p <  0.001), interventions (X2 = 26.8, p = 0.003), and referrals (X2 = 27.5, p = 0.002) were performed in or after the year 2015.

CONCLUSION

Clinic visits for shin injuries required the most clinical resources per episode of care. There were observed shifts in clinical assessment and treatment approaches to include more expanded nutritional and physiologic considerations.

Outpatient Runners Clinic Visit Trends and Injury Characteristics Among 392 Child and Adolescent Patients: A 10-year Chart Review

OBJECTIVE

To evaluate clinic visits and running-related injury (RRI) characteristics among child and adolescent runners seeking care at an outpatient clinic over a 10-year time frame.

DESIGN

Retrospective chart review.

SETTING

Outpatient hospital-affiliated Injured Runners Clinic.

PATIENTS

Children and adolescent runners (6-17 years) with RRIs.

INDEPENDENT VARIABLES

We examined electronic medical records (EMRs) among child and adolescent patients in the hospital database from 2011 to 2021 to obtain RRI characteristics and key demographic factors.

MAIN OUTCOME MEASURES

We assessed volume and frequency of patient visits to the clinic by RRI characteristics. Chi square analyses were used to compare the proportion of clinic visits over time and injury trends by body region and diagnosis.

RESULTS

There were 392 patients (sex: 277 F; mean age: 16.1 ± 1.3 years) and an average of 5 clinic visits per diagnosis (5 ± 4 visits; min: 1 visit, max: 31 visits). Number of visits generally increased over time up to 2016 but declined most drastically during the years of the pandemic (2020-2021; χ 2 = 644, P < 0 .001). Of the 654 new injury diagnoses, 77.68% were attributed to repetitive stress. Bone stress injuries to the tibia were the most common RRI (χ 2 = 1940, P < 0 .001; N = 132; 20.2% of all injuries) and constituted most of the clinic visits (χ 2 = 9271, P < 0 .001; N = 591; 25.4% of all visits).

CONCLUSION

We identified that adolescents with overuse injuries, particularly bone stress injuries to the tibia, constituted most of the visits to the outpatient healthcare setting. Clinicians should emphasize injury prevention efforts in clinical practice to reduce RRI burden.

Adolescent and young adult hip and knee strength profiles relate to running gait biomechanics

OBJECTIVES

Compare and assess relationships between strength and running biomechanics among healthy adolescents and young adult males and females.

DESIGN

Retrospective cohort.

SETTING

Clinic.

PARTICIPANTS

802 healthy participants (570 F, 232 M; 16.6 ± 2.3 years).

MAIN OUTCOME MEASURES

Mass-normalized knee flexor and extensor strength, hip adductor and abductor strength, hamstrings-to-quadriceps (H:Q), and abductor-to-adductor (Abd:Add) ratios were obtained using hand-held dynamometry. Mass-normalized peak vertical ground reaction force (vGRF), %stance, cadence, and stride length were obtained using an instrumented treadmill. Multivariate analyses of variance were used to compare strength and biomechanics across ages and sexes. Linear regressions were used to assess the relationships between strength and biomechanics, accounting for speed, age, and sex. Independent t-tests were used to compare strength between strength ratio profiles.

RESULTS

Strength and running biomechanics significantly differed between sexes (p-range: <0.001-0.05) and age groups (p-range: <0.001-0.02). Strength and strength ratios were significantly associated with increased cadence (p-range:0.001-0.04) and stride lengths (p-range:0.004-0.03), and decreased vGRF (p < 0.001). Lower H:Q ratios had significantly lower strength measures (p < 0.001). Higher Abd:Add ratios had significantly increased abductor strength (p < 0.001).

CONCLUSIONS

Strength and running biomechanics differed by sexes and ages. Hip and knee strength and strength ratios were related to select spatiotemporal and kinetic biomechanical features.

Generalized Joint Laxity Is Associated With Dynamic Hip Ultrasonography Measures in Female Athlete Patients Who Are Not Hypermobile

OBJECTIVES

To investigate ultrasound (US) femoroacetabular translation measurements in female athlete patients.

METHODS

A prospective cross-sectional study was conducted in female athlete patients <50 years. Demographic data, Beighton score/hypermobility status, and sport participation were collected. Hip dysplasia was determined using radiographic measurements (lateral center edge angle, anterior center edge angle, Tönnis angle); femoral version angles were measured with CT or MR. Femoroacetabular translation US measures included neutral (N), neutral flexed (NF), extension external rotation/apprehension (EER) positions. Maximal difference (delta) between US measures was calculated.

RESULTS

206/349 female hips were analyzed (median age 21.2 years [range, 12-49.5]). The primary sport group was performing arts (45%, 92/206). Mean Beighton score was 5.2 (SD, 2.5) with 61% (129/206) of hips exhibiting hypermobility (Beighton score ≥5). For each additional unit of Beighton score, N US measurement increased by 0.7 mm (β = 0.7; 95% confidence interval [CI] = 0.22-1.25; P < .001), NF by 1 mm ( β = 0.9; 95% CI = 0.3-1.43; P = .002) and EER by 0.8 mm ( β = 0.8; 95% CI = 0.27-1.37; P < .001) when adjusting for age and dysplasia status. A positive correlation was detected between NF (r = 0.19; 95% CI = 0.05-0.33; P = .007) and EER (r = 0.19; 95% CI = 0.05-0.32; P = .01) with Tönnis angle and a negative correlation between the delta and femoral version (r = -0.20; 95% CI = -0.35 to 0.03; P = .02). No difference in US measures was detected across sport groups (N [P = .24], NF [P = .51], EER [P = .20], delta [P = .07]).

CONCLUSION

Beighton score was independently associated with dynamic US measures in female athlete patients who are not hypermobile when controlling for other factors.

Biomechanical running gait assessments across prevalent adolescent musculoskeletal injuries

BACKGROUND

While there is substantial information available regarding expected biomechanical adaptations associated with adult running-related injuries, less is known about adolescent gait profiles that may influence injury development.

RESEARCH QUESTIONS

Which biomechanical profiles are associated with prevalent musculoskeletal lower extremity injuries among adolescent runners, and how do these profiles compare across injury types and body regions?

METHODS

We conducted a cross-sectional study of 149 injured adolescents (110 F; 39 M) seen at a hospital-affiliated injured runner's clinic between the years 2016-2021. Biomechanical data were obtained from 2-dimensional video analyses and an instrumented treadmill system. Multivariate analyses of variance covarying for gender and body mass index were used to compare continuous biomechanical measures, and Chi-square analyses were used to compare categorical biomechanical variables across injury types and body regions. Spearman's rho correlation analyses were conducted to assess the relationship of significant outcomes.

RESULTS

Patients with bony injuries had significantly higher maximum vertical ground reaction forces (bony: 1.87 body weight [BW] vs. soft tissue: 1.79BW, p = 0.05), and a higher proportion of runners with contralateral pelvic drop at midstance (χ² =5.3, p = 0.02). Maximum vertical ground reaction forces and pelvic drop were significantly yet weakly correlated (ρ = 0.20, p = 0.01). Foot strike patterns differed across injured body regions, with a higher proportion of hip and knee injury patients presenting with forefoot strike patterns (χ² =22.0, p = 0.01).

SIGNIFICANCE

These biomechanical factors may represent risk factors for injuries sustained by young runners. Clinicians may consider assessing these gait adaptations when treating injured adolescent patients.

Running gait biomechanics in female runners with sacroiliac joint pain

[Purpose] To identify running gait biomechanics associated with sacroiliac (SI) joint pain in female runners compared to healthy controls. [Participants and Methods] In this case-control study, treadmill running gait biomechanics of female runners diagnosed SI joint pain, (by ultrasound-guided diagnostic SI joint injection and/or ≥2 positive SI physical exam maneuvers) were compared with age, height, mass, and BMI matched healthy female runners. Sagittal and coronal plane treadmill running video angles were measured and compared. [Results] Eighteen female runners with SI pain, and 63 matched controls, were analyzed. There was no difference in age, height, mass, or BMI between groups. At the point of initial contact, runners with SI joint pain demonstrated less knee flexion, greater tibial overstride, and greater ankle dorsiflexion, compared to controls. In midstance, runners with SI pain had greater contralateral pelvic drop compared to controls. For unilateral SI joint pain cases (N=15), greater contralateral pelvic drop was observed when loading their affected side compared to the unaffected side. [Conclusion] Female runners with SI joint pain demonstrated greater contralateral pelvic drop during midstance phase; along with less knee flexion, greater “tibial overstride”, and greater ankle dorsiflexion at initial contact compared to controls.

Femoroacetabular translation in female athletes and dancers assessed by dynamic hip ultrasonography

Objective

To compare femoroacetabular (FA) translation between dancers and athletes with hip pain and between dancers with and without hip pain.

Methods

In this cross-sectional study, 171 female athletes and dancers with hip pain underwent dynamic hip ultrasound (DHUS) of FA translation in three positions: neutral (N), neutral with contralateral hip flexion (NF), apprehension position with contralateral hip flexion (EER-F). Multivariable linear regression analysis was used to assess variation in FA translation between dancers and athletes in the presence of age, Beighton score/hypermobility, BMI, radiographic markers of acetabular dysplasia and femoral version angles. Symptomatic dancers were matched to asymptomatic dancer controls on age, height and BMI, and comparison analyses of FA translation were conducted controlling for matched propensity score and Beighton score.

Results

In the symptomatic cohort, dancers were younger, had higher Beighton scores and were more hypermobile than non-dancers. Dancers also showed greater NF, EER-F and max US–min US (delta) compared with non-dancers (mean 5.4 mm vs 4.4 mm, p=0.02; mean 6.3 mm vs 5.2 mm, p=0.01; 4.2 mm vs 3.6 mm, p=0.03, respectively). Symptomatic dancers showed greater NF and EER-F compared with asymptomatic dancers (mean 5.5 mm vs 2.9 mm, p<0.001; mean 6.3 mm vs 4.2 mm, p<0.001, respectively). Comparison of symptomatic dancers with and without hip dysplasia showed no difference in DHUS measurements.

Conclusion

DHUS measurements of FA translation are greater in female dancers with hip pain relative to female non-dancer athletes with hip pain and asymptomatic female dancers.

Ultrasound Alpha Angles and Hip Pain and Function in Female Elite Adolescent Ballet Dancers

Femoroacetabular impingement (FAI) is a common anatomical variant in ballet dancers. Cam morphology (a subtype of FAI) and increased alpha angles have been identified as risk factors for hip pain. Ultrasound has recently been used to measure alpha angles in the diagnosis of cam morphology, but its utility remains understudied. The purpose of this study was to investigate the effect of ultrasound measured alpha angles on hip pain and function scores in elite female adolescent ballet dancers. The alpha angles of 25 dancers (mean age: 15.9 years) were measured using ultrasound and calculated with ImageJ Software. Cam morphology was defined by alpha angles of 60° or greater. Participants rated their hip pain and function using the International Hip Outcome Tool 12 (iHOT-12) survey. For normally distributed variables, the independent t-test was performed, and for abnormally distributed variables, the Mann-Whitney U Test. Along with mean and standard deviation (SD) values, median score, interquartile range (IQR), and 95% confidence intervals (95% CIs) were also analyzed. Significantly lower iHOT-12 scores were found in dancers with alpha angles ≥ 60° (mean ± SD, 74.34 ± 13.01; 95% CIs, 58.18, 90.50, median 67.20; IQR, 18.55), compared to dancers with alpha angles < 60° (mean ± SD, 80.22 ± 15.65; 95% CIs, 72.90, 87.54; median, 81.60; IQR, 16.35; p = 0.001). It is concluded that: 1. elite female adolescent ballet dancers with alpha angles higher than 60° experienced worse hip pain and function; 2. alpha angles may impact hip pain and function in these dancers; and 3. further studies should use a prospective design to investigate the predictive ability of their findings.

Running Propensities of Athletes with Hamstring Injuries

The current study aims to compare the mechanical propensities between healthy runners and runners with hamstring injuries. Retrospective case-control video analysis was used. A total of 35 (12 male and 23 female) videos of runners with hamstring injuries were compared with videos of sex-, age-, mass-, and height-matched healthy control runners. The main outcome variables were trunk posture angles, overstride angles, and foot strike patterns. An independent t-test and chi-squared tests were employed to analyze the main outcome variables between the runners with hamstring injuries and the healthy control runners. The statistical significance of less than 0.05 (p < 0.05) was used. The runners with hamstring injuries had a 1.6° less forward-trunk posture angles compared with the healthy control runners (p = 0.043). Also, the runners with hamstring injuries demonstrated a 4.9° greater overstride angles compared with the healthy control runners (p = 0.001). Finally, the runners with hamstring injuries had a tendency of rearfoot strike, while the healthy control runners showed a forefoot strike pattern (p = 0.004). In conclusion, the runners with hamstring injuries demonstrated different running mechanical propensities compared with the healthy runners.

Short-term Effect of Ultrasound-Guided Iliopsoas Peritendinous Corticosteroid Injection

OBJECTIVES

Treatment for iliopsoas tendinopathy includes ultrasound (US)-guided iliopsoas peritendinous corticosteroid injection. Evidence is lacking regarding US-guided iliopsoas injection efficacy in patients with iliopsoas tendinopathy and intra-articular (IA) hip abnormalities. The purpose of this study was to examine the efficacy of US-guided iliopsoas corticosteroid injection for iliopsoas tendinopathy in patients with and without IA hip abnormalities.

METHODS

This work was a prospective study evaluating patients aged 12 to 50 years with iliopsoas tendinopathy. Participants completed a Hip Disability and Osteoarthritis Outcome Score (HOOS) questionnaire before and 6 weeks after injection. The main outcome measure was the change in HOOS subcategory scores. Independent variables included time and hip status. Normal hips were compared to abnormal hips with IA abnormalities. A 2-way repeated measures analysis of covariance with effect size (η² ) was used to determine injection effects on HOOS scores before and 6 weeks after injection.

RESULTS

A total of 178 patients (154 female and 24 male) were analyzed. Time effects were found for both normal and abnormal hips in all HOOS subcategories: symptoms (P = .041; η²  = 0.050), pain (P = .001; η²  = 0.184), activities of daily living (P = .011; η²  = 0.076), function in sports and recreation (P = .001; η²  = 0.151), and quality of life (QOL; P = .001; η²  = 0.193). Significant differences between normal versus abnormal hips were found in the sports and recreation (P = .032; η²  = 0.056) and QOL scores (P = .001; η²  = 0.135).

CONCLUSIONS

In patients with iliopsoas tendinopathy, US-guided iliopsoas corticosteroid injection improved outcomes regardless of coexisting IA hip abnormalities. Patients without IA hip abnormalities showed greater improvement in sports and recreation and QOL scores compared to patients with IA hip abnormalities. Ultrasound-guided iliopsoas injection for iliopsoas tendinopathy may advance short-term care and help continue with nonsurgical treatment regimens.

Diagnostic Accuracy of Magnetic Resonance Imaging and Computed Tomography Scan in Young Athletes With Spondylolysis

The objective of this study was to determine diagnostic accuracy of magnetic resonance imaging (MRI) and computed tomography (CT) scans in young athletes diagnosed with spondylolysis. A cross-sectional study was used. Twenty-two young athletes (14.7 ± 1.5 years) were diagnosed as spondylolysis based on a single-photon emission CT. Following the diagnosis, participants underwent MRI and CT scan imaging tests on the same day. The sensitivity and false-negative rate of the MRI and CT scans were analyzed. MRI test confirmed 13 (+) and 9 (-) results while CT test showed 17 (+) and 5 (-) results. The sensitivity and false-negative rate of MRI were, respectively, 59.1% (95% confidence interval [CI] = 36.7% to 78.5%) and 40.9% (95% CI = 21.5% to 63.3%). Furthermore, the sensitivity and false-negative rate of CT scan were 77.3% (95% CI = 54.2% to 91.3%) and 22.7% (95% CI = 0.09% to 45.8%). Our results indicated that CT scan is a more accurate imaging modality to diagnose spondylolysis compared with MRI in young athletes.

Ultrasound examination and patellar tendinopathy scores in asymptomatic college jumpers

OBJECTIVE

To investigate the prevalence of hypoechoic areas by US and its' association with VISA-P scores among asymptomatic jumpers while highlighting sex comparisons.

DESIGN

Cross-sectional study.

SETTING

Pre-participation exam at a National Collegiate Athletic Association (NCAA) division I college.

PARTICIPANTS

Thirty-one college athletes who engage in jumping sports.

MAIN OUTCOME MEASURES

Hypoechoic images of patellar tendon captured by ultrasound examination were compared to a self-reported knee functional survey, the Victorian Institute of Sport Assessment for patellar tendinopathy (VISA-P) scale (0-100).

RESULTS

With a total of 31 athletes (13 males and 18 females), prevalence rate of the hypoechoic areas of patellar tendon was 19.4% (6/31) in the right knee and 29.0% (9/31) in the left knee. There was no proportional difference in a comparison of prevalence rate of hypoechoic area [(+) or (-)] by sex in either right or left knee. The VISA-P scores were significantly lower in US (+) than US (-) in the right knee (p = 0.003, Cohen's d = 1.675), but not the left knee (p = 0.250, Cohen's d = 0.512). The receiver operating characteristics curve analysis indicated the most sensitive and specific VISA-P values based on status [(+) or (-)] of hypoechoic area was 89.5 with 86.4% and 77.7% of sensitivity and specificity.

CONCLUSION

In short, hypoechoic areas were detected by US examination among self-reported asymptomatic jumpers. There was an association between hypoechoic areas and VISA-P scores in the right knee, but not in left knee. VISA-P scores may be used as a screening tool for the presence of hypoechoic areas.

Running mechanics of females with bilateral compartment syndrome

[Purpose] Primary purpose was to compare running mechanics between healthy runners and runners with chronic exertional compartment syndrome (CECS) including overstride angles, ankle dorsiflexion (DF) angles, and foot strike patterns. The secondary purpose was to analyze the association between the overstride angles and ankle DF angles. [Participants and Methods] Running images of 7 female runners with bilateral CECS patients were captured at a time of the medical examination. Their running images were compared with gender, age, and body mass index matched 31 healthy control runners. [Results] The bilateral CECS female runners have a propensity of running with significantly greater overstride and ankle DF angles than the healthy female runners. There were no foot strike differences between the two cohorts. There were a non-significant, poor relationship between overstride and ankle DF angles in the healthy female runners while a significant, strong association was found between overstride and ankle DF angles in the bilateral CECS female runners. [Conclusion] Compared to healthy female runners, bilateral CECS female runners demonstrated different running mechanics including greater overstride and ankle DF angles. The two variables were strongly associated with each other in bilateral CECS female runners, but not in healthy female runners. This may potentially contribute to the mechanism of CECS development.

Bony Morphology of Femoroacetabular Impingement in Young Female Dancers and Single-Sport Athletes

BACKGROUND

Femoroacetabular impingement (FAI) is a painful and limiting condition of the hip that is often seen in young athletes. Previous studies have reported a higher prevalence of this disorder in male athletes, but data on the structural morphology of adolescent and young adult female athletes, specifically those involved in dance, are lacking.

PURPOSE

(1) To investigate the radiographic morphology of FAI deformities in adolescent and young adult female single-sport dance and nondance athletes and (2) to examine the differences in the radiographic findings between these 2 groups.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

A retrospective chart review of 56 female single-sport athletes 10 to 21 years of age with a diagnosis of FAI within a single-sports medicine division of a pediatric academic medical center was performed. Acetabular index (AI), lateral center-edge angle (LCEA), crossover sign, and ischial spine sign were measured bilaterally on anteroposterior radiographs; alpha angle (AA) was measured on lateral films, and anterior center-edge angle (ACEA) was measured on false-profile films. Independent t tests and Mann-Whitney U tests were used to compare mean angle measurements between dance and nondance athletes. Dichotomized categorical variables and crossover and ischial spine signs were analyzed between dance and nondance athletes by applying a chi-square test. Statistical significance was set as P < .05 a priori.

RESULTS

Significant differences in angle measurements were noted. AA was significantly lower in the dancers compared with the nondance athlete group (49.5° ± 6.0° vs 53.9° ± 7.3°, P = .001). The LCEA and ACEA of dance athletes were significantly greater compared with nondance athletes (33.8° ± 6.7° vs 30.9° ± 5.8° [P = .016] and 36.0° ± 8.1° vs 32.3° ± 7.0° [P = .035], respectively). No significant difference in AI was seen between the 2 cohorts (5.0° ± 4.0° for dancers vs 5.9° ± 3.4° for nondancers, P = .195).

CONCLUSION

Significant differences existed in the radiographic bony morphology of young female single-sport dance athletes compared with nondance athletes with FAI. In dance athletes, symptoms were seen in the setting of normal bony morphology.

Sex and growth effect on pediatric hip injuries presenting to sports medicine clinic

To compare sports-related hip injuries on the basis of sex and age in a cohort of young athletes. A 5% random probability sample of all new patients' charts over a 10-year time period was selected for investigation. The most common hip injury diagnoses, sport at time of injury, mechanism (acute/traumatic vs. overuse), and types (bony vs. soft tissue) were compared by sex and age (preadolescent vs. adolescent). Descriptive and χ-analyses were carried out. The interaction of sex and age with respect to hip injury over time was examined by two-way (sex, age) analysis of variance. A total of 2133 charts were reviewed; N=87 hip injuries. The main diagnoses for males included labral tear (23.1%), avulsion fracture (11.5%), slipped capital femoral epiphysis (11.5%), dislocation (7.7%), and tendonitis (7.7%). The main diagnoses for females were labral tear (59.0%), tendonitis (14.8%), snapping hip syndrome (6.6%), strain (4.9%), and bursitis (4.9%). The five most common sports/activities at the time of hip injury were dancing/ballet (23.0%), soccer (18.4%), gymnastics (9.2%), ice hockey (8.1%), and track and field (6.9%). Age by sex comparisons showed a greater proportion of the total hip injuries (38.5%) in males compared with females (8.2%) during preadolescence (5-12 years). However, in adolescence (13-17 years), the hip injury proportion was significantly higher in females (91.8%) compared with males (61.5%; P<0.001). Injury mechanism and type differed by sex, with females sustaining more chronic/overuse (95.1%) and soft tissue type injuries (93.4%) compared with males (50.0 and 53.8%, respectively; P<0.001). Females were found to have a sharper increase in hip injury proportion as they progressed through puberty compared with males (analysis of variance sex-by-age interaction; P<0.001). Hip injury mechanism and type differed significantly between males and females during growth. Notably, the proportion of hip injuries in the young female athletes showed a significantly greater increase with advancing age compared with males. Hip injuries in children and the interplay with growth, as it relates to injury predisposition, require further investigation to facilitate efforts aimed at prevention.

LEVEL OF EVIDENCE III

Cross-sectional epidemiological study.

Eye Protection and Risk of Eye Injuries in High School Field Hockey

OBJECTIVE

To determine if injury rates among female field hockey players differ before and after implementation of a national mandate for protective eyewear (MPE).

METHODS

We analyzed girls' field hockey exposure and injury data collected from national (High School Reporting Information Online [RIO]) and regional (Fairfax County Public Schools) high school sports injury databases in 2 seasons before (2009/10 and 2010/11) and 2 seasons after (2011/12 and 2012/13) a national MPE.

RESULTS

The incidence of eye/orbital injuries was significantly higher in states without MPE (0.080 injuries per 1000 athletic exposures [AEs]) than in states with MPE (before the 2011/12 mandate) and the postmandate group (0.025 injuries per 1000 AEs) (odds ratio 3.20, 95% confidence interval 1.47-6.99, P = .003). There was no significant difference in concussion rates for the 2 groups (odds ratio 0.77, 95% confidence interval 0.58-1.02, P = .068). After the 2011/12 MPE, severe eye/orbital injuries (time loss >21 days) were reduced by 67%, and severe/medical disqualification head/face injuries were reduced by 70%. Concussion rates for field hockey (0.335 per 1000 AEs) rank third among girls' sports included in the High School RIO surveillance program.

CONCLUSIONS

Among female high school field hockey players, MPE is associated with a reduced incidence of eye/orbital injuries and fewer severe eye/orbital and head/face injuries. Concussion rates did not change as a result of the national MPE. Concussion remains the most common injury involving the head and face among female field hockey players, prompting further inquiry into potential effects of adopting protective headgear/helmets.

Effectiveness of protective eyewear in reducing eye injuries among high school field hockey players

OBJECTIVE

To determine if injury rates differ among high school field hockey players in states that mandated protective eyewear (MPE) versus states with no protective eyewear mandate (no MPE).

METHODS

We analyzed field hockey exposure and injury data collected over the 2009-2010 and 2010-2011 scholastic seasons from national and regional databases.

RESULTS

Incidence of all head and face injuries (including eye injuries, concussion) was significantly higher in no-MPE states compared with MPE states, 0.69 vs 0.47 injuries per 1000 athletic exposures (incidence rate ratio [IRR] 1.47; 95% confidence interval [CI]: 1.04-2.15, P = .048). Players in the no-MPE group had a 5.33-fold higher risk of eye injury than players in the MPE group (IRR 5.33; 95% CI: 0.71-39.25, P = .104). There was no significant difference in concussion rates for the 2 groups (IRR 1.04; 95% CI: 0.63-1.75, P = .857). A larger percentage of injuries sustained by athletes in the no-MPE group required >10 days to return to activity (32%) compared with athletes in the MPE group (17%), but this difference did not reach statistical significance (P = .060).

CONCLUSIONS

Among high school field hockey players, playing in a no-MPE state results in a statistically significant higher incidence of head and face injuries versus playing in an MPE state. Concussion rates among players in MPE and no-MPE states were similar, indicating that addition of protective eyewear did not result in more player-player contact injuries, challenging a perception in contact/collision sports that increased protective equipment yields increased injury rates.

Back pain in adolescent athletes

Back pain in the young athlete is a common complaint and often perceived as a challenging problem. A well-directed approach will usually provide the practitioner with a higher comfort zone. The etiology of back pain in the pediatric and adolescent population is different from that of the adult population due to the presence of open physes and increased linear growth velocity. In addition, the frequency and intensity of sports participation in children continues to increase, leading to more overuse injuries. This review article will discuss the anatomy and physiology of the spine and pelvis, as well as focus on the chronic and overuse causes of back pain in the young athlete.

Patellofemoral pain syndrome: evaluation of location and intensity of pain

OBJECTIVES

To identify the sites and intensity of pain in patients with patellofemoral pain syndrome.

METHOD

A prospective cohort study was conducted at an academic sports medicine practice in Boston, Massachusetts. All patients met inclusion criteria and were enrolled and evaluated during the study time frame. A single sports medicine orthopaedic surgeon examined a consecutive sample of patients with patellofemoral pain not explained by one of several well-defined anterior knee pain diagnoses. The study group consisted of 100 patients (75 females, 25 males) with median age of 14 years. Eleven discrete locations were palpated for tenderness. Hamstring tightness was evaluated by measuring the popliteal angle. Patients reported intensity of pain using a 0- to 9-point ordinal scale. Regression and nonparametric statistical methods were used.

RESULTS

The most common site of pain was the patella during anterior-posterior compression (90 patients), followed by the distal pole of the patella, the medial plica, and the nonarticular medial femoral condyle. Median "worst pain" intensity was 6 out of a possible 9. The most common site of "worst pain" was also the patella in compression (63 patients). Median duration of symptoms was 10 months, with an interquartile range of 3 to 20 months. Pain intensity was inversely correlated with duration of symptoms (P < 0.01).

CONCLUSIONS

In these patients with patellofemoral pain syndrome, the major source of pain was the patella subchondral bone.

Skeletal scintigraphy of young patients with low-back pain and a lumbosacral transitional vertebra

Lumbosacral transitional vertebrae can alter the biomechanics of weight transfer at the affected spinal segment. Low-back pain may result. This study assessed what skeletal scintigraphy reveals about stress associated with a lumbosacral transitional vertebra in young patients with low-back pain.

METHODS

The study population included 48 patients (30 male, 18 female; age range, 6-19 y; mean age, 15.7 y) with low-back pain and a lumbosacral transitional vertebra. Skeletal scintigraphy was correlated with plain radiographs in all, CT in 12, and MRI in 11.

RESULTS

High uptake was shown at the articulation between the transverse process of a lumbosacral transitional vertebra and the sacrum in 39 (81%) of the patients. In 23 (59%) of the 39 patients with high uptake, this finding was shown only by SPECT. In 13 (81%) of the 16 for which the high uptake was shown by planar imaging, the anterior projection was more valuable than the posterior projection. In 9 (23%) of the 39 patients with high uptake at the transverse-sacral articulation, the lumbosacral transitional vertebra had not been noted in a radiographic report before skeletal scintigraphy but was identified through reevaluation or repetition of radiographs after skeletal scintigraphy. Radiographs showed sclerosis along the transverse-sacral articulation in only 8 (21%) of the 39 patients with high uptake. Findings indicating stress or motion at the joint were shown by CT in 6 (55%) of 11 and by MRI in 5 (63%) of 8 patients with high uptake at the transverse-sacral articulation who underwent these examinations.

CONCLUSION

Skeletal scintigraphy often indicates stress at the transverse-sacral articulation of young patients with low-back pain and a lumbosacral transitional vertebra. Showing evidence of stress is best accomplished using SPECT. Changes are usually not radiographically evident, but there is a trend for MRI and CT to show findings that imply stress or motion at the articulation. The unique ability of skeletal scintigraphy to provide this physiologic information supports its use in these patients.

Spondylolysis: returning the athlete to sports participation with brace treatment

Between 1988 and 1995, 73 adolescent athletes treated with the Boston Overlap Brace for spondylolysis were reviewed to evaluate improvement in pain score and activity level. A favorable clinical outcome was achieved in 80%. Girls and boys who participated in high-risk sports were five times more likely to have an unfavorable clinical outcome than those who participated in low-risk sports (odds ratio = 5, 95% confidence interval = 2.4-7.5, P = .003). In addition, acute onset of pain and hamstring tightness were associated with a worse outcome. Athletes with symptomatic spondylolysis treated with an antilordotic brace can expect improvement in their clinical course and return to sports participation in 4-6 weeks.

Does football cause an increase in degenerative disease of the lumbar spine?

Degenerative disease of the lumbar spine is exceedingly common. Whether any specific activity increases the likelihood of developing degenerative disc disease (DDD) or facet degeneration (FD) has enormous implications. Within the field of occupational medicine there are specific activities, occupations, and morphologic characteristics that have been related to low back pain. Several specific risk factors have been conclusively linked to low back pain, and in particular DDD and FD. Within the sport of American football, there has long been the feeling that many athletes have or will develop low back pain, DDD, and FD. Proving that certain risk factors present in football will predictably lead to an increase in LBP, DDD, and FD is more difficult. At this time, it can be said that football players, in general, increase their risk of developing low back pain, DDD, and FD as their years of involvement with their sport increase. Because specific spine injuries like fracture, disc herniation, and spondylolysis are more frequent in football players, the resulting DDD and FD are greater than that of the general population. The weightlifting and violent hyperextension that are part of American football are independent risk factors for degenerative spine disease.

Back injuries in the young athlete

The diagnosis of back pain in the young athlete should be specific and not attributed to nonspecific, mechanical causes. Risk factor identification and intervention are required. Treatment is then initiated in a specific pattern, addressing flexibility and muscular imbalances. Bracing is often used to allow healing of growth tissue. The lumbosacral orthosis may be molded in a lordotic posture to unload the disc or antilordotic posture to relieve the posterior column; however, customizing the lordosis to the individual biomechanics may be required. Spinal stabilization is initiated with therapy for strengthening isolated weaknesses and progressing to coactivation and proprioceptive techniques, such as the balance ball. Returning to competition is preceded with sport-specific training.