Journal of Sport Rehabilitation最新文献

Context: Individuals with chronic hip-related groin pain display impaired dynamic postural control as measured by the modified star excursion balance test; however, the kinematics and kinetics displayed have not been reported in chronic hip-related groin pain populations. Hip joint kinematics during various tasks differ between males and females with chronic hip-related groin pain; however, few studies have reported trunk kinematics or hip joint loading. We were curious if sex differences exist in trunk, hip, and pelvis kinematics and hip joint loading during the modified star excursion balance test among those with chronic hip-related groin pain.

Design: Cross-sectional.

Methods: Patients with chronic hip-related groin pain performed 3 trials of the modified star excursion balance test, reaching in anterior, posteromedial, and posterolateral directions. We used a motion capture system and force plates to capture hip, pelvis, and trunk kinematic and kinetic data. Variables of interest included reach distance, normalized by leg length, and sagittal and frontal plane hip, pelvis, and trunk kinematics and hip joint kinetics at the time of max reach. We used independent t tests or Wilcoxon rank sum tests to assess between-group differences.

Results: Compared with males (n = 11, age = 28 years, body mass index = 25.0 kg/m2), females (n = 17, age = 25 years, body mass index = 22.1 kg/m2) displayed larger hip adduction angle during anterior (12.6° vs 6.1°, P = .048) and posteromedial (1.5° vs -4.6°, P = .043) directions, larger contralateral pelvic drop angle during anterior direction (-1.7° vs 2.3°, P = .014), smaller trunk flexion angle during posteromedial direction (25.8° vs 34.8°, P = .045), and smaller hip flexion moment during posterolateral direction (0.56 vs 0.87 N·m/kg, P = .021). Females and males displayed similar reach distances.

Conclusion: Movement strategies differ between sexes, with females displaying more hip adduction motion, more contralateral pelvic drop, less trunk flexion motion, and smaller hip flexion moments.

Context: Running-related Achilles tendon injuries have been observed more frequently in males, which may reflect sex differences in tendon morphology or mechanics during running. Males exhibit a larger Achilles tendon cross-sectional area and some measures of Achilles tendon loading in running, but sex differences in measures of tendon loading have not been thoroughly characterized. This study examines sex differences in the Achilles tendon cross-sectional area and Achilles tendon loading variables associated with running kinetics and kinematics.

Design: Cross-sectional.

Methods: Recruited from a university population, 26 female and 23 male healthy recreational runners ran at 3.35 m/s on an instrumented treadmill and were assessed using 3-dimensional motion capture, musculoskeletal modeling, and diagnostic ultrasound. A multivariate analysis examined differences between sexes in Achilles tendon loading and additional running variables with alpha set to .05. Mean differences (MD) and confidence intervals (CIs) were reported.

Results: Males displayed greater peak Achilles tendon force (MD = 0.94 body weight [BW]; 95% CI, -1.48 to -0.33), peak gastrocnemius force (MD = 0.52 BW; 95% CI, -0.75 to -0.29), and Achilles tendon cross-sectional area (MD = 0.1 cm2; 95% CI, -0.15 to 0.04) compared with females (P < .05). No group differences were observed in peak Achilles tendon stress (MD = 4.13 kPa; 95% CI, -16.25 to 7.98), peak Achilles tendon strain (MD = 0.41; 95% CI, -1.60 to 0.78), peak soleus force (MD = 0.34 BW; 95% CI, -0.76 to 0.078), foot strike angle (MD = 3.1; 95% CI, -1.65 to 7.85), or peak vertical ground reaction force (MD = 0.106; 95% CI, -0.24 to 0.03) (P > .05).

Conclusions: Male runners produced greater peak Achilles tendon force when running at the same speed, but similar peak Achilles tendon stress was observed between male and female recreation runners. Male runners had a greater Achilles tendon cross-sectional area. These findings may have implications to running-related injury based on sex.

Context: Patellofemoral joint loading after anterior cruciate ligament reconstruction (ACLR) remains poorly understood, despite the high prevalence of patellofemoral joint complications following surgery. With an observational cohort design, we compared patellofemoral joint stress (PFJS) and reaction force (PFJRF) between surgical and nonsurgical limbs during a double-limb squat at 12 weeks postsurgery and return to sport (RTS), with sex-based comparisons.

Methods: Forty-seven athletes (21 males and 26 females) aged 12-25 years performed a body weight double-limb squatting task at 12 weeks postoperatively and RTS. Maximal knee extensor strength was assessed at both time points with isokinetic dynamometry. Ground reaction forces and kinematic data were used to compute patellofemoral loading. Mixed factorial analyses of variance compared patellofemoral loading and knee extension strength, and Pearson correlations examined associations between patellofemoral loading and knee extensor strength.

Results: The surgical limb demonstrated lower PFJS (P < .001, ηp2=.439) and PFJRF (P < .001, ηp2=.423) at both time points, though these measures increased over time without significant changes in the nonsurgical limb. Females exhibited lower PFJS (P < .001, d = 0.73) and PFJRF (P = .032, d = 0.52) than males across limbs and time points. Knee extensor strength was positively associated with PFJS (r = .697; r = .616) and PFJRF (r = .605; r = .531, all P < .01) at both 12 weeks postsurgery and RTS, respectively.

Conclusion: Athletes demonstrate decreased patellofemoral joint loading in the surgical versus the nonsurgical limb through RTS. Females exhibit lower patellofemoral loading after ACL reconstruction, which may be linked to their higher prevalence of posttraumatic osteoarthritis and patellar abnormalities-supporting the paradoxical hypothesis that underloading, rather than overloading, may promote osteoarthritis development.

Context: Pull-based portable dynamometers may provide an affordable and clinically feasible alternative for objectively assessing quadriceps strength after anterior cruciate ligament reconstruction. We examined the reliability, validity, and diagnostic accuracy of a pull-based dynamometer compared with an isokinetic dynamometer when assessing quadriceps strength in young adults with a history of anterior cruciate ligament reconstruction.

Design: Controlled laboratory study.

Methods: Our sample included 25 individuals with a history of unilateral anterior cruciate ligament reconstruction >4 months prior. We performed 3 tests of bilateral quadriceps strength during a single laboratory visit with 5 minutes of rest between tests. We first tested with the isokinetic dynamometer and then performed 2 tests with the pull-based dynamometer (test and retest). For each test, we collected the average maximal knee extension torque from 3 trials on each limb and then calculated normalized unilateral quadriceps strength (Newton meter per kilogram) on each limb and limb symmetry index. We assessed intrarater reliability and validity using intraclass correlation coefficients (ICC) with 95% confidence intervals (CI) for absolute agreement (reliability and validity) and consistency (validity). We assessed diagnostic accuracy using sensitivity and specificity calculations for the pull-based dynamometer's ability to identify individuals with or without a limb symmetry index <90% compared with the isokinetic dynamometer.

Results: The pull-based dynamometer demonstrated good-to-excellent test-retest reliability for all strength outcomes (ICC 95% CI = .89-.99). The pull-based dynamometer demonstrated good-to-excellent consistency (ICC 95% CI = .79-.98) with the isokinetic dynamometer for all 3 outcomes, but poor-to-excellent agreement (ICC 95% CI = .13-.96). The pull-based dynamometer identified 84% of participants with or without a limb symmetry index <90% with perfect specificity (100%) and good sensitivity (71%).

Conclusions: The pull-based dynamometer performed reliable, consistent, and diagnostically accurate quadriceps strength measures compared with the isokinetic dynamometer, but strength values were not interchangeable between devices. Pull-based portable dynamometry may provide a low-cost, alternative tool for objectively assessing quadriceps strength when an isokinetic dynamometer is unavailable.

Context: Hip crepitus creates negative emotions and beliefs, leading to adaptations in sports and daily life activities. People with hip/groin pain present psychological responses to pain, and hip crepitus severity may amplify those features. We aimed to explore associations between self-reported hip crepitus severity and pain, quality of life, and psychological features at baseline and 2-year follow-up in football players with hip/groin pain.

Design: Longitudinal.

Methods: We recruited 184 football players with hip/groin pain (20% females, mean age [SD] = 27.6 [0.4]). Self-reported crepitus severity was assessed using a single item of the International Hip Outcome Tool-33. Pain severity was assessed using a Numeric Pain Rating Scale describing average pain playing football and average pain in the last month. Quality of life was assessed using the Copenhagen Hip and Groin Outcome Score subscale. Psychological features included standardized measures of kinesiophobia and pain catastrophizing. We assessed associations between crepitus severity and these outcomes using linear regression.

Results: At baseline, greater (worse) hip crepitus severity was associated with worse average pain in the last month (β = -0.02), quality of life (β = 0.16), and kinesiophobia (β = -0.05). We found sex interactions for pain catastrophizing and average pain playing football, with stronger associations in females (β = -0.19 and β = -0.03) than males (β = -0.09 and β = -0.01). Hip crepitus severity at baseline was not associated with changes in pain, quality of life, or psychological features over 2 years.

Conclusion: Worse hip crepitus severity was cross-sectionally associated with worse pain, quality of life, and psychosocial features in football players with hip/groin pain, but not with the progression of these outcomes over 2 years. Females had a stronger association between hip crepitus and pain catastrophizing and average pain playing football than males at baseline.

Context: Clinicians assessing limb symmetry after ACL reconstruction (ACLR) use various tools including functional tests (eg, countermovement jump [CMJ]) and isolated strength tests (eg, isometric isokinetic dynamometry). However, it is unclear how these different assessment modalities and calculation methods compare, which may have significant implications for clinical decision making when interpreting asymmetry.

Design: A repeated-measures, cross-sectional observational study.

Methods: Fourteen participants post-ACLR (phase 3 rehabilitation) and 25 healthy controls were assessed. Participants completed unilateral isometric knee extension testing on an isokinetic dynamometer and bilateral CMJ testing on a dual force plate system. Asymmetry was calculated using 5 different equations.

Results: A within-group analysis showed that participants post-ACLR had significantly different asymmetry magnitudes when comparing the CMJ and isometric tests (mean difference = 5.64%-12.45%, P < .006). Healthy controls showed no difference in asymmetry between the 2 tests (P > .617). A between-group analysis showed that the ACLR group was significantly more asymmetric than controls on both the CMJ test (mean difference = 7.95%-22.12%, P < .001) and the isometric test (mean difference = 14.02%-36.24%, P < .001). However, both testing methods exhibited adequate sensitivity (0.79) and specificity (0.99) for differentiating those with ACLR from healthy controls.

Conclusion: Asymmetry values are highly dependent on the assessment modality (functional jump vs isolated strength). While participants post-ACLR were more asymmetric than healthy controls on both tests, the magnitude of their asymmetry differed significantly between the 2 tests. This finding indicates that asymmetry values from functional and isolated tests are not interchangeable and underscores the need for test-specific interpretation in clinical practice.

Context: Quadriceps impairment is evident in patellofemoral pain, yet its underlying mechanisms remain unclear, particularly the potential contribution of corticospinal mechanisms. We aimed to explore corticospinal excitability of the quadriceps in individuals with patellofemoral pain.

Design: Cross-sectional.

Methods: We included 21 individuals with patellofemoral pain (57% women) and 21 pain-free controls (66% women). Corticospinal excitability was assessed via transcranial magnetic stimulation, measuring resting motor threshold, active motor threshold, cortical silent period, and short-interval intracortical inhibition. Quadriceps strength (Lafayette Manual Muscle Tester) and force sense (Chattanooga Stabilizer Pressure Biofeedback) were evaluated bilaterally in the patellofemoral pain group and in the dominant limb of pain-free controls. Self-reported measures included pain intensity, knee function, physical activity, and kinesiophobia.

Results: Individuals with patellofemoral pain had a longer cortical silent period duration than pain-free controls (ηp2=.133, p = .030). A longer cortical silent period was associated with greater pain duration (r = .389, p = .021) and pain intensity (r = .345, p = .042) and lower knee function (r = -.366, p = .030) and quadriceps strength (r = -.298, p = .029). No between-group or between-limb differences were found for resting motor threshold, active motor threshold, or short-interval intracortical inhibition.

Conclusions: Individuals with patellofemoral pain exhibited bilaterally longer cortical silent periods, reflecting increased cortical and corticospinal inhibition. Associations with pain, function, and strength suggest that neurophysiological alterations may contribute to clinical manifestations. These findings provide novel insights that could inform future rehabilitation strategies for patellofemoral pain.

Context: Clinical assessments of the cervical spine and vestibular/oculomotor systems may inform return-to-play (RTP) clearance time after concussion and inform individualized concussion prognosis. Our objective was to investigate whether cervical spine and vestibular/oculomotor clinical assessments were associated with RTP clearance time after concussion.

Design: Prospective cohort study.

Methods: Adolescents ages 13-18 years within 3 weeks of concussion completed assessments of symptom severity using the Post-Concussion Symptom Inventory, cervical spine proprioception (head repositioning accuracy [HRA]), and symptom provocation with vestibular/oculomotor testing (visio-vestibular exam [VVE]; assesses smooth pursuits, saccades, vestibulo-ocular reflex, and motion sensitivity). HRA was performed with eyes closed and involved patients relocating their head to a neutral starting position after right/left rotation and cervical spine flexion/extension. The mean distance (distance between center position and each self-reported center point) across 12 trials was used in analysis as the measure of HRA error. For VVE, we used the number of tests that provoked symptoms for analysis. We then monitored participants until they received RTP clearance from their physician. We used multivariable linear regression with RTP clearance time (days from concussion to RTP clearance) as the outcome, HRA error and number of positive VVE subtests as predictors, adjusting for covariates.

Results: We assessed 68 participants (age = 15.8 (1.4) y, 59% female, mean = 11.0 (3.8) d of postconcussion). After adjusting for age, sex, concussion history, initial symptom severity (Post-Concussion Symptom Inventory score), and days from concussion to assessment, neither HRA error (hazard ratio = 0.89; 95% confidence interval, 0.71-1.12; P = .34) or number of positive VVE subtests (hazard ratio = 1.06; 95% confidence interval, 0.91-1.24; P = .47) were associated with RTP clearance time.

Conclusions: Cervical spine proprioception and vestibular/oculomotor symptom provocation evaluated within 3 weeks of injury were not associated with RTP clearance time, potentially reflecting the complexity and multifaceted nature of RTP decisions.

Context: The double-leg Landing Error Scoring System (LESS) identifies noncontact ACL injury risk. However, its intersession reliability has been examined in only one study. As such injuries often occur during single-leg landings, research on the single-leg LESS (SLESS) in field settings remains lacking. Therefore, our study investigated the intersession, intrarater, and interrater reliability of single- and double-leg jump-landing tasks using SLESS and LESS.

Methods: Thirty-five team-sports players (age: 26.4 [6.7] years, n = 28 males and 7 females) performed 3 jump-landing variations (single-leg dominant and nondominant and double leg) across 3 sessions. We conducted sessions 1 and 2 on the same day, with session 3 one week later. Three assessors rated video footage to determine SLESS and LESS total scores. Reliability was assessed using the intraclass correlation coefficient (ICC), standard error of measurement, and coefficient of variation (CV) with 95% CIs.

Results: Intersession reliability for the SLESS and LESS scores showed good to excellent ICCs (dominant leg: .89, nondominant leg: .91, double leg: .79) with moderate CVs (dominant leg: 6.5%, nondominant leg: 6.6%, double leg: 7.9%). Intrarater reliability for the SLESS and LESS scores also demonstrated good to excellent ICCs (dominant leg: .94, nondominant leg: 0.92, double leg: .88) with moderate CVs (dominant leg: 5.0%, nondominant leg: 6.0%, double leg: 5.6%). Interrater reliability for the SLESS and LESS scores exhibited good ICCs (dominant leg: .82, nondominant leg: .83, double leg: .79) but poor CVs (dominant leg: 10.5%, nondominant leg: 11.5%, double leg: 11.5%). Single-leg LESS and LESS scores exhibited small standard error of measurement values between 1.05 and 1.11 for all reliability measures.

Conclusions: The SLESS and LESS are reliable field-based tools for assessing jump-landing tasks among team-sports players, facilitating confidence in sports and exercise science research.

Context: Objectively evaluating knee stability in multiple planes in individuals with anterior cruciate ligament injury may provide more comprehensive information than evaluating subjectively or in only a single plane. This could support both research and clinical decision making. However, for the clinical value of such an instrument to be evaluated, reliability and validity of the instrument must first be established. Despite multiple available instruments that measure rotational knee stability, it is not clear which of these instruments has adequate reliability and validity.

Objective: We performed a systematic review to identify instruments for measuring rotational knee stability and to synthesize the available literature in which validity and reliability were evaluated.

Evidence acquisition: We searched 4 databases for publications reporting reliability or validity of an instrument designed to assess rotational knee stability. A narrative synthesis was used to present the results.

Evidence synthesis: We identified 42 studies evaluating 25 different instruments designed to measure movement while applying a standardized torque or while a tester performed a manual test (eg, pivot shift). There was high heterogeneity in parameters reported and criterion methods used. Intrarater and interrater reliability intraclass correlation coefficients were consistently adequate (>.75) except for when lower torques (ie, 6 N·m or less) were applied or acceleration or jerk was measured instead of laxity. Four out of 19 (21.1%) studies evaluating validity reported very good correlations (r > .8) with a criterion measure.

Conclusions: We found no high-quality evidence that provided sufficient evidence of both reliability and validity in any device. To evaluate the clinical benefit of objectively evaluating stability in multiple planes, further work is needed to develop, refine, and evaluate this class of devices.