Large-scale assessment of physical activity in a population using high-resolution hip-worn accelerometry: the German National Cohort (NAKO)

Large population-based cohort studies utilizing device-based measures of physical activity are crucial to close important research gaps regarding the potential protective effects of physical activity on chronic diseases. The present study details the quality control processes and the derivation of physical activity metrics from 100 Hz accelerometer data collected in the German National Cohort (NAKO). During the 2014 to 2019 baseline assessment, a subsample of NAKO participants wore a triaxial ActiGraph accelerometer on their right hip for seven consecutive days. Auto-calibration, signal feature calculations including Euclidean Norm Minus One (ENMO) and Mean Amplitude Deviation (MAD), identification of non-wear time, and imputation, were conducted using the R package GGIR version 2.10-3. A total of 73,334 participants contributed data for accelerometry analysis, of whom 63,236 provided valid data. The average ENMO was 11.7 ± 3.7 mg (milli gravitational acceleration) and the average MAD was 19.9 ± 6.1 mg. Notably, acceleration summary metrics were higher in men than women and diminished with increasing age. Work generated in the present study will facilitate harmonized analysis, reproducibility, and utilization of NAKO accelerometry data. The NAKO accelerometry dataset represents a valuable asset for physical activity research and will be accessible through a specified application process.

Comparison Between Movement Pattern Training and Strengthening on Kinematics and Kinetics in Patients With Chronic Hip-Related Groin Pain

The purpose of this study was to compare the preliminary effects of movement pattern training (MoveTrain) versus strengthening/flexibility (standard) treatment on hip and pelvic biomechanics in patients with chronic hip-related groin pain. This is a secondary analysis of data collected during a pilot randomized clinical trial. Thirty patients with hip pain, between the ages of 15 and 40 years, were randomized to MoveTrain or standard. Both groups completed 10 treatment sessions over 12 weeks along with a daily home exercise program. Three-dimensional motion analysis was used to collect kinematic and kinetic data of the pelvis and hip during a single-leg squat task at pretreatment and immediately posttreatment. Compared with the standard group, the MoveTrain group demonstrated smaller hip adduction angles (P = .006) and smaller hip external adduction moments (P = .008) at posttreatment. The desired changes to hip joint biomechanics, as found in this study, may require specificity in training that could allow health care professionals to better customize the rehabilitation of patients with hip pain. These findings can also be applied to the design and implementation of future clinical trials to strengthen our understanding of the long-term implications of different rehabilitation techniques for patients with hip pain.

No difference in prevalence of postoperative iliopsoas tendinitis in patients undergoing arthroscopic hip surgery when using absorbable versus non-absorbable suture for capsular closure

PURPOSE

The volume of arthroscopic hip surgery has increased dramatically in recent years with iliopsoas tendinitis (IPT) being one of the most common complications of this procedure. The purpose of this study is to investigate the prevalence of post-operative IPT in patients who undergo arthroscopic hip surgery with capsular closure using absorbable versus non-absorbable suture.

METHODS

This is a single center, single surgeon, retrospective analysis performed between August 2007 and May 2023 comparing two cohorts who underwent hip arthroscopy. Patients were divided into those who underwent surgery with capsular closure using absorbable (Vicryl®, Johnson and Johnson, New Brunswick, NJ) suture and those who underwent capsular closure with non-absorbable suture (Suturetape, Arthrex, Naples FL). All patients who underwent primary or revision hip arthroscopy and were at least 2 months post-operation were initially included in the study.

RESULTS

Between August 2007 and May 2023 a total of 1513 hip arthroscopy surgeries were performed. Within this cohort, 1421 hips underwent hip arthroscopy with non-absorbable suture and 64 hips underwent surgery with absorbable suture. There was no significant difference between the proportion of IPT in the non-absorbable cohort (2.3%) versus the absorbable cohort (1.6%) (P = 0.669).

CONCLUSION

Capsular closure with Absorbable sutures was non-inferior to capsular closure with non-absorbable sutures with respect to the proportion of post-operative IPT following hip arthroscopy for FAI. Additionally, the proportion of post-operative IPT was found to be significantly higher in patients undergoing revision versus primary hip arthroscopy, regardless of capsular closure suture type.

LEVEL OF EVIDENCE

IV.

Hip Contact Forces During Sprinting in Femoroacetabular Impingement Syndrome

PURPOSE

Sprinting often provokes hip pain in individuals with femoroacetabular impingement syndrome (FAIS). Asphericity of the femoral head-neck junction (cam morphology) characteristic of FAIS can increase the risk of anterior-superior acetabular cartilage damage. This study aimed to 1) compare hip contact forces (magnitude and direction) during sprinting between individuals with FAIS, asymptomatic cam morphology (CAM), and controls without cam morphology, and 2) identify the phases of sprinting with high levels of anteriorly directed hip contact forces.

METHODS

Forty-six recreationally active individuals with comparable levels of physical activity were divided into three groups (FAIS, 14; CAM, 15; control, 17) based on their history of hip/groin pain, results of clinical impingement tests, and presence of cam morphology (alpha angle >55°). Three-dimensional marker trajectories, ground reaction forces, and electromyograms from 12 lower-limb muscles were recorded during 10-m overground sprinting trials. A linearly scaled electromyogram-informed neuromusculoskeletal model was used to calculate hip contact force magnitude (resultant, anterior-posterior, inferior-superior, medio-lateral) and angle (sagittal and frontal planes). Between-group comparisons were made using two-sample t -tests via statistical parametric mapping ( P < 0.05).

RESULTS

No significant differences in magnitude or direction of hip contact forces were observed between FAIS and CAM or between FAIS and control groups during any phase of the sprint cycle. The highest anteriorly directed hip contact forces were observed during the initial swing phase of the sprint cycle.

CONCLUSIONS

Hip contact forces during sprinting do not differentiate recreationally active individuals with FAIS from asymptomatic individuals with and without cam morphology. Hip loading during early swing, where peak anterior loading occurs, may be a potential mechanism for cartilage damage during sprinting-related sports in individuals with FAIS and/or asymptomatic cam morphology.

Editorial Commentary: Physical Therapy Alone May Not Successfully Treat Patients With Hip Pain and Large α Angles or Decreased Femoral Anteversion Combined With Femoroacetabular Impingement Syndrome

Understanding the relation between spinopelvic (lumbopelvic) tilt and femoracetabular impingement syndrome (FAIS) is complex, and determining the optimal patient parameters that lead to successful nonoperative management is vital. Physical therapy (PT) focusing on core and posterior chain strengthening is often successful. PT can change the posterior tilt of the pelvis by 5° to 10°, allowing increased range of motion (ROM) and decreased impingement of the hip. However, PT does not change cam anatomy. Thus, PT alone may not sufficiently increase ROM in patients with cam-type impingement and large α angles or limited femoral anteversion. Pelvic compensation may lead to successful nonoperative management of FAIS, but not in all patients. Large-cam, high-flexion athletes with chronic hip pain should try PT. Yet, while some patients with large cam lesions may improve without surgery if femoral version and/or pelvic tilt ROM can be increased, surgery should not be excessively delayed in patients with poor prognostic factors for nonoperative management.

Running Alterations Pre- and Postarthroscopy for Femoroacetabular Impingement Syndrome and Labral Tears

ABSTRACT

Freemyer, B, Beeler, D, Crawford, S, Durkin, R, and Stickley, C. Running alterations pre- and postarthroscopy for femoroacetabular impingement syndrome and labral tears. J Strength Cond Res 38(3): 501-509, 2024-Running is essential to sports participation and activity over the lifespan; however, running biomechanics are not fully described in patients with femoroacetabular impingement (FAIS). The purpose was to compare FAIS patient report outcome surveys (PRO) and running biomechanics preoperatively and 6 months postoperatively with controls. Nineteen subjects (FAIS, n = 10 and age-matched controls, n = 9) were included. The UCLA, Hip Outcome Score activity of daily living (HOS ADL ) and sports subscale (HOS SS ), and 3-D running biomechanics were evaluated. Statistical parametric mapping was conducted on biomechanics data. Statistical significance was set at p ≤ 0.05. Femoroacetabular impingement had similar UCLA activity scores compared with controls by 6 months (FAIS: 8.4 ± 1.7, CON: 8.6 ± 2.0, p = 0.80), despite lower HOS ADL (FAIS-Six: 89.3 ± 6.3, CON: 100 ± 0, p = 0.04) and HOS SS (FAIS-Six: 82.6 ± 18.5, CON: 100 ± 0, p = 0.05). The FAIS group had lower knee adduction moments (KAM) around 22-27% of stance ( p = 0.05) and lower sagittal plane ankle power generation during the final 5% of stance compared with the controls ( p = 0.04) preoperatively. The FAIS also had lower vertical ground reaction forces the first 2% of stance ( p = 0.05) and lower KAM from 20 to 30% stance ( p = 0.03) at the postoperative time vs. controls. Femoroacetabular impingement had higher hip external rotation angles the first 5% stance ( p = 0.05) and the last 20% of stance ( p = 0.01) vs. controls. This is the first study to describe FAIS running pre- and postoperatively. Despite higher activity and health 6 months postarthroscopy, the patients with FAIS had altered running biomechanics. Clinicians should consider these findings when creating rehabilitation protocols and during running progressions across the postoperative care of patients with FAIS.

Risk Factors for Suboptimal Outcome of FAI Surgery in the Adolescent Patient

BACKGROUND

Surgical treatment for adolescent patients with femoroacetabular impingement (FAI) is increasing. The purpose of this study was to determine the clinical outcomes of FAI surgery in a multicenter cohort of adolescent patients and to identify predictors of suboptimal outcomes.

METHODS

One hundred twenty-six adolescent hips (114 patients < 18 years of age) undergoing surgery for symptomatic FAI were studied from a larger multicenter cohort. The group included 74 (58.7%) female and 52 male hips (41.3%) with a mean age of 16.1 (range 11.3 to 17.8). Clinical outcomes included the modified Harris Hip Score (mHHS), Hip disability and Osteoarthritis Outcome Score (5 domains), and University of California Los Angeles activity score. Failure was defined as revision surgery or clinical failure (inability to reach minimally clinical important differences or patient acceptable symptoms state for the mHHS). Statistical analysis was used to identify factors significantly associated with failure.

RESULTS

There was clinically important improvement in all patient-reported outcomes for the overall group, but an 18.3% failure rate. This included a revision rate of 8.7%. Females were significantly more likely than males to be classified as a failure (25.7 vs. 7.7%, P =0.01), in part because of lower preoperative mHHS (59.1 vs. 67.0, P < 0.001). Mild cam deformity (alpha angle <55 degrees) was present in 42.5% of female hips compared with 17.3% male hips. Higher alpha angles were inversely correlated with failure. Alpha angles >63 have a failure rate of 8.3%, between 55 and 63 degrees, 12.0% failure rate, and <55 degrees (mild cam) failure rate of 37.5%. Patients who participated in athletics had a 10.3% failure rate compared with nonathletes at 25.0% ( P =0.03, RR (relative risk) 2.4).

CONCLUSIONS

Adolescent patients undergoing surgical treatment for FAI generally demonstrate significant improvement. However, female sex, mild cam deformities, and lack of sports participation are independently associated with higher failure rates. These factors should be considered in surgical decision-making and during patient counseling.

LEVEL OF EVIDENCE

Level III-retrospective comparative study.

Peripheral nerve stimulation for psoas muscle pain

The psoas muscle is the largest muscle in the lower lumbar spine and is innervated by the ipsilateral lumbar spinal nerve roots (L2-L4). Here, we present a 44-year-old female with left hip pain in the posterolateral aspect of the left hip radiating to the ipsilateral hamstring, and psoas atrophy (based on imaging). She is now reported to have over 50% improvement in pain scores after underdoing temporary peripheral nerve stimulation of the psoas muscle as well as significant improvement in muscle atrophy based on an electromyography (EMG) study. This case study is the first to report documented improvement in muscle atrophy based on EMG after peripheral nerve stimulation of the targeted area.

The Preserved Thickness Ratio of the Femoral Head Contributes to the Collapse Predictor of Osteonecrosis

OBJECTIVES

The collapse of femoral head is a serious symptom of osteonecrosis of the femoral head (ONFH), resulting in hip pain and deformity. However, it is hardly possible to reestablish the femoral head nonoperatively once the collapse happens. Predicting femoral head collapse is of great value for the prognosis of ONFH. This study aimed to develop a new method to quantify the preserved thickness of femoral head and to assess its diagnostic contribution in predicting femoral head collapse on plain radiographs.

METHODS

This was a single-center retrospective study. A total of 101 hips (85 patients) with ARCO stage II from January 2008 to December 2016 were included in this study. The preserved thickness was measured on standard anteroposterior (AP) and frog-leg (FL) radiographs. The anteroposterior view's preserved thickness ratio (APTR) and the frog-leg view's preserved thickness ratio (FPTR) were calculated to show the preserved thickness ratio of the femoral head anteriorly and laterally. Univariate and multivariate logistic regression was performed to determine the risk factors for collapse. Sensitivity, specificity, and cut-off values for APTR and FPTR were determined by the receiver operating characteristic (ROC) curve analysis. Kaplan-Meier (K-M) analysis was applied to determine femoral head survival in ONFH patients.

RESULTS

The mean age of the 27 females and 58 males was 38.93 years old. The mean follow-up time was 74.62 (36-124) months in the non-collapse group and 18.66 (3-82) months in the collapse group. Femoral head collapse was observed in 62 hips during the follow-up period. Logistic regression analysis and ROC results showed that APTR <24.79% and FPTR <10.62% were significantly correlated with femoral head collapse. The Kaplan-Meier survival curve suggested that the overall survival rate of APTR ≥24.79% was 68.2% at 5 and 10 years and FPTR ≥10.62% was 71.63% at 5 and 10 years. At the last follow-up, 26 hips had collapse on the anterior side of the femoral head, 12 hips occurred on the lateral side, and 24 hips happened to collapse on both anterior and lateral sides.

CONCLUSION

Femoral head collapse predominantly occurred anteriorly rather than laterally in ONFH patients. The measurements of APTR and FPTR have noticeable implications for the prediction of femoral head collapse, and contribute to the selection of treatment options for ONFH patients with types B and C1 according to the JIC classification.

Dynamic joint stiffness in individuals with femoroacetabular impingement syndrome pre- and post-hip arthroscopy

BACKGROUND

Patients with hip-related pain often fail to return to their desired level of activity following hip arthroscopy. Lasting biomechanics alterations may be one potential explanation. Dynamic joint stiffness assesses the mechanistic controls of the lower limb during high impact movements, and thus, may provide valuable clinical targets to improving movement and optimizing return to activity after surgery.

METHODS

Twenty-five participants (13 females) with hip-related pain underwent 3D motion capture during a drop jump task before surgery and six months post-operatively. Nineteen healthy controls (9 females) were collected for comparison. Sagittal plane dynamic joint stiffness was calculated during the initial landing phase. Baseline and 6-month dynamic joint stiffness data were compared 1) between males and females with hip-related pain and 2) between individuals with hip-related pain and controls using Wilcoxon Signed-Rank and Mann Whitney U tests. Sexes were analyzed separately.

FINDINGS

From baseline to 6 months post-operatively, females with hip-related pain demonstrated decreased dynamic ankle stiffness (2.26 Nm/deg. [0.61] to 1.84 Nm/deg. [0.43]) (p = .005) and males with hip-related pain demonstrated increased dynamic hip stiffness (2.73 [0.90] to 3.88 [1.73]) (p = .013). There were no differences in dynamic stiffness at any joint between individuals with hip-related pain at either timepoint when compared to controls (p ≥ .099).

INTERPRETATION

Females and males with hip-related pain may demonstrate unique changes in dynamic joint stiffness after surgery, indicating return to activity may follow different trajectories for each sex. Additional work should examine the relationship between hip joint stiffness and treatment outcomes and identify additional movement-related rehabilitation targets.

Analysis of the natural collapse course of non-traumatic osteonecrosis of the femoral head based on the matrix model

BACKGROUND

There are many predictions about the progression of natural collapse course of osteonecrosis of the femoral head. Here, we aimed to combine the three classical prediction methods to explore the progression of the natural collapse course.

METHODS

This retrospective study included 127 patients admitted to our hospital from October 2016 to October 2017, in whom the femoral head had not collapsed. Logistic regression analysis was performed to determine the collapse risk factors, and Kaplan-Meier survival curves were used for femoral head survival analysis. The collapse rate of the femoral head was recorded within 5 years based on the matrix model. The specificity of the matrix model was analyzed using the receiver operating characteristic curve.

RESULTS

A total of 127 patients with a total of 202 hips were included in this study, and 98 hips collapsed during the follow-up period. Multivariate logistics regression analysis showed that the predictive ability of the matrix model was stronger than Association Research Circulation Osseous staging, Japanese Investigation Committee classification, and area (P < 0.05). Kaplan-Meier survival curve showed that the median survival time of femoral head in patients was 3 years. The result of the receiver operating characteristic curve analysis showed that the area under the curve (AUC) of the matrix model had better predictive value (AUC = 0.771, log-rank test: P < 0.001).

CONCLUSION

We creatively combined the three classical prediction methods for evaluating the progression of the natural collapse course based on the matrix model and found that the higher the score of the matrix model, the higher the femoral head collapse rate. Specifically, the matrix model has a potential value in predicting femoral head collapse and guiding treatment selection.

Change in hip laxity after anterior capsular suture in total hip arthroplasty using direct anterior approach

It is clinically unclear whether anterior capsular suture improves hip laxity in total hip arthroplasty using direct anterior approach (DAA-THA). This study aimed to clarify the impact of anterior capsular suture for hip laxity in DAA-THA. In this study, 121 hips of 112 patients who underwent DAA-THA were prospectively enrolled. Mean age was 64.7 ± 10.1 years, and the subjects consisted of 35 hips in 32 men and 86 hips in 80 women. To evaluate hip laxity after implantation, axial head transfer distance (HTD) when the hip was pulled axially at 15 kg was compared before and after anterior capsular suture at the hip intermediate and 10° extension positions. HTD in the intermediate and 10° extension positions averaged 5.9 ± 4.6 mm and 6.3 ± 4.6 mm before the suture, and 2.6 ± 2.7 mm and 2.9 ± 3.1 mm after the suture, respectively. HTD after the suture significantly decreased in both hip positions (p < 0.0001). The amount of change by the suture was greater in cases with greater pre-suturing HTD. In DAA-THA, the anterior capsular suture significantly improved hip laxity against axial traction force, it may contribute to improvement of postoperative hip stability, especially in cases with greater laxity before the suture.

Factors associated with cam deformity in Japanese local residents

Femoroacetabular impingement has increasingly been recognized as a cause of primary hip osteoarthritis; however, its epidemiological indications remain unclear. We aimed to clarify the epidemiological indications and factors associated with cam deformity in a large-scale population-based cohort in Japan. Overall, 1480 participants (2960 hips) (491 men, 989 women; mean age, 65.3 years) analyzed in the third survey of the Research on Osteoarthritis/Osteoporosis Against Disability study were included. The α angle and spinopelvic parameters (lumbar lordosis, sacral slope, pelvic tilt, and pelvic incidence) were radiographically measured. Cam deformity was defined as α angle ≥ 60°. Overall, the cam deformity prevalence was 147/2960 (5.0%). Cam deformity prevalence tended to increase with age; in the univariate analysis, a higher percentage of men was observed in the group with cam deformity than in the group without it. No relationship was observed between cam deformity and hip pain. Factors associated with α angle were examined via multiple regression analysis for each gender; α angle was significantly associated with age and BMI in each gender. The α angle and PT were correlated in women. Thus, α angle and cam deformity prevalence increase with age in Japanese individuals. Accordingly, cam deformity can be considered a developmental disease.

Diagnostic Accuracy of Clinical Tests for Assessing Greater Trochanteric Pain Syndrome: A Systematic Review With Meta-analysis

OBJECTIVE: We aimed to evaluate the accuracy of clinical tests that are used to diagnose greater trochanteric pain syndrome (GTPS) in clinical practice. DESIGN: Diagnostic test accuracy systematic review with meta-analysis. LITERATURE SEARCH: MEDLINE, Embase, CINAHL, AMED, and SPORTDiscus were searched using key words mapped to diagnostic test accuracy for GTPS. STUDY SELECTION CRITERIA: Studies with published or derivable diagnostic accuracy data were included. DATA SYNTHESIS: Risk of bias was assessed using the QUADAS-2 tool, and certainty of evidence, via the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) framework. MetaDTA "R" random-effects models were used to summarize individual and pooled data including sensitivity, specificity, likelihood ratios, and pretest/posttest probabilities. RESULTS: From a database yield of 858 studies, 23 full texts were assessed. We included 6 studies for review, involving 15 tests and 272 participants (314 hips). Overall certainty of evidence ranged from very low to moderate. Meta-analysis of 6 tests revealed sequenced test clusters able to significantly shift pretest-posttest probability for or against a GTPS diagnosis. In people reporting lateral hip pain, a negative gluteal tendon (GT) palpation test followed by a negative resisted hip abduction test significantly reduced the posttest probability of GTPS from 59% to 14%. In those with a positive GT palpation test followed by a positive resisted hip abduction test, the posttest probability of GTPS significantly shifted from 59% to 96%. CONCLUSION: The value of magnetic resonance imaging for diagnosing GTPS is debated. We have identified a straightforward, clinically useful diagnostic test cluster to help confirm or refute the presence of GTPS in people reporting lateral hip pain. J Orthop Sports Phys Ther 2024;54(1):1-24. Epub 10 August 2023. doi:10.2519/jospt.2023.11890.

Two-stage multi-task deep learning framework for simultaneous pelvic bone segmentation and landmark detection from CT images

PURPOSE

Pelvic bone segmentation and landmark definition from computed tomography (CT) images are prerequisite steps for the preoperative planning of total hip arthroplasty. In clinical applications, the diseased pelvic anatomy usually degrades the accuracies of bone segmentation and landmark detection, leading to improper surgery planning and potential operative complications.

METHODS

This work proposes a two-stage multi-task algorithm to improve the accuracy of pelvic bone segmentation and landmark detection, especially for the diseased cases. The two-stage framework uses a coarse-to-fine strategy which first conducts global-scale bone segmentation and landmark detection and then focuses on the important local region to further refine the accuracy. For the global stage, a dual-task network is designed to share the common features between the segmentation and detection tasks, so that the two tasks mutually reinforce each other's performance. For the local-scale segmentation, an edge-enhanced dual-task network is designed for simultaneous bone segmentation and edge detection, leading to the more accurate delineation of the acetabulum boundary.

RESULTS

This method was evaluated via threefold cross-validation based on 81 CT images (including 31 diseased and 50 healthy cases). The first stage achieved DSC scores of 0.94, 0.97, and 0.97 for the sacrum, left and right hips, respectively, and an average distance error of 3.24 mm for the bone landmarks. The second stage further improved the DSC of the acetabulum by 5.42%, and this accuracy outperforms the state-of-the-arts (SOTA) methods by 0.63%. Our method also accurately segmented the diseased acetabulum boundaries. The entire workflow took ~ 10 s, which was only half of the U-Net run time.

CONCLUSION

Using the multi-task networks and the coarse-to-fine strategy, this method achieved more accurate bone segmentation and landmark detection than the SOTA method, especially for diseased hip images. Our work contributes to accurate and rapid design of acetabular cup prostheses.

Does Screening Ultrasound Timing in Developmental Dysplasia of the Hip Need to be Adjusted for Moderate Preterm and Near-term Infants: A Prospective Study

INTRODUCTION

An initial screening ultrasound is essential for patients at higher risk of developmental dysplasia of the hip (DDH) due to breech presentation or a family history of DDH. The American Academy of Pediatrics recommends screening ultrasounds to be performed after 6 weeks of age to reduce the rate of false positives. However, there is limited evidence regarding whether these screening ultrasounds need to be adjusted for gestational age in prematurity. The purpose of this study was to evaluate the influence of moderate preterm and near-term births on screening hip ultrasounds for high-risk DDH populations.

METHODS

We identified all prospectively enrolled patients in a single-center database referred for screening hip ultrasound for DDH. We included those hips referred for risk factors of DDH, including breech presentation, family history of DDH, or hip click, and excluded those with known dysplasia or referral for hip instability. Each ultrasound was measured by a pediatric radiologist to determine the alpha angle and femoral head coverage. Patients were classified as "premature" if born at <37 weeks gestation or "full term" if born at ≥37 weeks gestation. All patients underwent screening hip ultrasound between 5 and 8 weeks of age. Sonographic markers of dysplasia and the incidences of abnormal ultrasound and Pavlik harness treatment were compared between cohorts. Significance was set at P <0.05.

RESULTS

A total of 244 hips in 122 patients were included, 58 hips in the premature cohort and 186 hips in the full-term cohort. The premature cohort had a significantly decreased gestational age compared with the full-term cohort (35.4 ± 1.1 vs 38.5 ± 1.1 wk, respectively, P < 0.001). However, there was no difference between premature and full-term cohorts in sex distribution (69% vs 75%, females, P = 0.39), unadjusted age at the time of ultrasound (6.6 ± 0.7 vs 6.8±0.7 wk, respectively, P = 0.07), or referral reason ( P = 0.14). On hip ultrasound, there was no difference between premature and full-term cohorts with respect to alpha angle (62.6 ± 3.3 vs 62.2 ± 5.3 degrees, P = 0.41), femoral head coverage (54.9 ± 6.3 vs 55.1 ± 10.6, P = 0.19), rate of abnormal ultrasound (18.3% vs 20.7%, respectively, P = 0.68), or the rate of Pavlik harness treatment (0% vs 5.3%, respectively, P = 0.12).

DISCUSSION

There was no significant difference in alpha angle or femoral head coverage between premature and full-term patients at 5 to 8 weeks of unadjusted age. This preliminary data suggests that screening ultrasounds can be performed without adjusting for prematurity.

LEVEL OF EVIDENCE

Level II, prognostic study.

Lower limb vertical stiffness and frontal plane angular impulse during perturbation-induced single limb stance and their associations with gait in individuals post-stroke

After stroke, deficits in paretic single limb stance (SLS) are commonly observed and affect walking performance. During SLS, the hip abductor musculature is critical in providing vertical support and regulating balance. Although disrupted paretic hip abduction torque production has been identified in individuals post-stroke, interpretation of previous results is limited due to the discrepancies in weight-bearing conditions. Using a novel perturbation-based assessment that could induce SLS by removing the support surface underneath one limb, we aim to investigate whether deficits in hip abduction torque production, vertical body support, and balance regulation remain detectable during SLS when controlling for weight-bearing, and whether these measures are associated with gait performance. Our results showed that during the perturbation-induced SLS, individuals post-stroke had lower hip abduction torque, less vertical stiffness, and increased frontal plane angular impulse at the paretic limb compared to the non-paretic limb, while no differences were found between the paretic limb and healthy controls. In addition, vertical stiffness during perturbation-induced SLS was positively correlated with single support duration during gait at the paretic limb and predicted self-selected and fast walking speeds in individuals post-stroke. The findings indicate that reduced paretic hip abduction torque during SLS likely affects vertical support and balance control. Enhancing SLS hip abduction torque production could be an important rehabilitation target to improve walking function for individuals post-stroke.

Editorial Commentary: Femoral Version and Capsular Thickness Analysis in Hip Preservation Surgery-Surgical Indications Are as Important as Surgical Technique

Optimal treatment of patients with femoroacetabular impingement syndrome requires both thoughtful decision-making and skillful operative technique. Traditional evidence-based literature and routine clinical practice overemphasize the role of the alpha angle on the femoral side and lateral center edge angle on the acetabular side. Femoral and acetabular version are critical values that influence outcomes and warrant measurement and consideration. Without version analysis, an uniformed, possibly poor, decision may be made. The literature and clinical practice also place dichotomous emphasis on labral (torn/intact) and capsular (torn/intact) integrity, with minimal appreciation of the morphological details of both. Not all capsules are created equal. "Normal" capsule thickness is a nebulous concept, with thinner anterior capsules more prone to anterior instability. Intuitively, it biomechanically stands to reason that excessive femoral anteversion (and excessive anterior cranial and central acetabular version) would place additional stress on the anterior capsule. Excessive femoral anteversion is associated with a thinner anterior capsule. Whether the latter is a reactive process (implies causation) or simply 2 concordant metrics (only correlation) has yet to be determined. In patients with nonarthritic hip pain, comprehensive quantitative consideration of both femoral and acetabular version and capsular thickness determines the optimal hip preservation procedure. Surgical indications are as important as surgical technique.

Evaluation and Management of the Athlete's Hip

Hip and groin pain is common in athletes, and there are many possible underlying pathologies. It is important to describe athletic hip pathology in the context of sport-specific physiologic loads and biomechanical demands. Three distinct types of athletes with this pathology are collision athletes, hypermobility athletes, and endurance athletes. Although there is considerable overlap between sports, athletes with hip pain should always be evaluated in the context of their sport. Understanding the effect of sport-specific biomechanical demands may help with both diagnosis and treatment of athletic hip pathology; however, each athlete's injury should be analyzed on an individual basis.

Effects of hip joint kinematics on the effective pelvis stiffness and hip impact force during simulated sideways falls

Improved understanding is required on how hip fracture risk is influenced by landing configuration. We examined how hip impact dynamics was affected by hip joint kinematics during simulated sideways falls. Twelve young adults (7 males, 5 females) of mean age 23.5 (SD = 1.5) years, participated in pelvis release experiments. Trials were acquired with the hip flexed 15° and 30° for each of three hip rotations: +15° ("external rotation"), 0°, and -15° ("internal rotation"). During falls, force-deformation data of the pelvis were recorded. Outcome variables included the peak hip impact force (Fexperimental) and effective stiffness of the pelvis (k1st, ksecant, and kms) determined with different methods suggested in literature, and predicted hip impact force during a fall from standing height (F1st, Fsecant and Fms). The two-way repeated-measures ANOVA was used to test whether these variables were associated with hip joint angles. The Fexperimental, ksecant and Fsecant were associated with hip rotation (F = 5.587, p = 0.005; F = 9.278, p < 0.0005; F = 5.778, p = 0.004, respectively), and 15 %, 31 % and 17 % smaller in 15° external than internal rotation (848 versus 998 N; 24.6 versus 35.6 kN/m; 2,637 versus 3,170 N, respectively). However, none of the outcome variables were associated with hip flexion (p > 0.05). Furthermore, there were no interactions between the hip rotation and flexion for all outcome variables (p > 0.05). Our results provide insights on hip impact dynamics, which may help improve a hip model to assess hip fracture risk during a fall.

Influence of a passive exoskeleton on kinematics, joint moments, and self-reported ratings during a lifting task

It was found that the Auxivo LiftSuit reduced the load on the back and hip muscles when lifting heavy loads, but its effect on lower body kinematics, joint moments, and self-reported ratings was unclear. The purpose of this study was to assess the effect of this passive lift-exoskeleton design, on lower body kinematics, joint moments, and self-reported ratings during lifting of heavy loads. Twenty healthy subjects performed lifting of heavy loads with and without the exoskeleton under surveillance of a motion capture system. Medium and maximum level adjustments of the exoskeleton, as well as no exoskeleton use were analyzed. Our results indicate significant reduction (p <.01) in pelvis segment tilt and hip flexion ROM with the exoskeleton at maximum level adjustment in males during lifting. Lumbosacral flexion moment ranges were significantly decreased (p <.013) with the exoskeleton at maximum and medium level adjustment in males during lifting. The general user impressions were mostly positive, with participants reporting that it was easier to perform the task with the exoskeleton than without it (p <.0.001), and preferring and recommending the exoskeleton for the task. Although our findings may suggest negative effects of the Auxivo LiftSuit in males and females due to a ROM restriction and loose fit, respectively, it does not mean that the Auxivo LiftSuit is not useful for lifting tasks. Further design improvements are required to allow full range of motion of hips and pelvis, as well to provide better adjustment and level of support in female users.

Hip Pain in Adolescent Patients

Hip pain is a common complaint in adolescents. There are several causes for hip pain in this population, with dysplasia and impingement being the most common; however, other conditions such as extra-articular impingement, torsional disorders, labral tears, and osteochondral lesions also require consideration. Many of these conditions are related to underlying anatomic abnormalities and increased activity in this age group. An understanding of the common pathologies of the adolescent hip is integral to the evaluation, diagnosis, and treatment of these patients.

Soft Tissue Cam Impingement in Adolescents: MRI Reveals Impingement Lesions Underappreciated on Radiographs

BACKGROUND

Femoroacetabular impingement (FAI) has been described as repetitive and abnormal contact between a structurally abnormal proximal femur (cam) and/or acetabulum (pincer), occurring during the terminal range of motion of the hip. While cam and pincer lesions have traditionally been defined as osseous abnormalities, there may be a subset of adolescent patients whose impingement is primarily soft tissue (nonosseous). The existence of a nonosseous cam lesion in adolescents with FAI has not been well described.

PURPOSE

To identify and characterize a series of adolescent patients with nonosseous (soft cam) FAI identified on magnetic resonance imaging (MRI) and compare these patients' clinical presentation and outcome with those of a cohort with primary osseous cam FAI in the same age group.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A prospective institutional registry of patients with symptomatic FAI was reviewed. Patients were included if they had an MRI scan and a lateral radiograph of the hip (45° Dunn or frog) at a baseline visit. On MRI, the anterolateral femoral head was evaluated using radial, coronal, sagittal, or axial oblique sequences. A soft cam lesion was identified by the presence of soft tissue thickening of ≥2 mm at the anterolateral femoral head-neck junction. An alpha angle was measured on MRI scans and radiographs when a lesion was identified. The cohort with soft cam lesions was reviewed and findings and outcomes were compared with those of a cohort with osseous cam lesions. Continuous variables were first examined for normality, and then nonparametric tests-such as the Kruskal-Wallis test-were considered. The change between pre- and postoperative patient-reported outcomes (PROs) was described by mean and standard deviation and evaluated with an independent-samples t test.

RESULTS

A total of 31 (9.3%) of 332 hips (mean age, 16.4 years [range 13.1-19.6 years]; women, 83.9%) were identified with a soft tissue impingment lesion on MRI at the femoral head-neck junction between the 12 and 3 o'clock positions. These lesions demonstrated a thickened perichondral ring (71%), periosteal thickening (26%), or a cartilaginous epiphyseal extension (3%). The mean alpha angle on MRI was greater than on radiographs (63.5°± 7.9° vs 51.3°± 7.9°; P < .0001). A total of 22 patients (71%) with soft impingement underwent hip preservation surgery. When compared with patients in the osseous cohort who also underwent surgical management, both groups showed similar significant improvements from pre- to postoperatively (soft: modified Harris Hip Score [mHHS], 26.9 ± 18.2; Hip disability and Osteoarthritis Outcome Score [HOOS], 31.4 ± 22.9; osseous: mHHS, 22.8 ± 20.8; HOOS, 27.4 ± 20.1; P < .0001), with a mean follow-up of 3.4 years (range, 1-7 years) in the soft cam cohort and 3 years (1-10.1 years) in the osseous cam cohort.

CONCLUSION

Clinicians should be aware of nonosseous or soft cam lesions that cause impingement in adolescent patients without an obvious osseous cam on radiographs. MRI is required to detect these soft cam lesions. When nonoperative treatment fails, the PROs in these patients after operative management are comparable with those in patients with osseous cam lesions. Further research is needed to determine whether the soft cam precedes an osseous cam or whether it is a separate entity.

Sciatic nerve palsy after direct anterior approach for total hip replacement

SummarySciatic nerve injury after total hip replacement is rare with a reported incidence of about 0.09%-3.7%. The most commonly reported causes include traction on the nerve during reduction, compression of the nerve from subfascial haematoma, significant leg lengthening, improper retractor placement, thermal burns from cautery and extraneous cement. We present a case of complete sciatic nerve palsy in a patient operated on using direct anterior approach (DAA). To date, there are no reports describing sciatic nerve palsy secondary to haematoma immediately after primary arthroplasty through the DAA. We performed an MRI of lumbosacral spine with both hips, which revealed a haematoma. Consequently, we promptly took the patient to the operation theatre for re-exploration. Using the same approach, we dislocated the hip and removed the clots. By the end of 2 weeks, the patient was able to dorsiflex the ankle and had fully recovered from sciatic nerve palsy.

Unravelling the hip-spine dilemma from the CHECK-cohort: is sagittal pelvic morphology linked to radiographic signs of femoroacetabular impingement?

INTRODUCTION

To date the aetiology of femoroacetabular impingement (FAI) is still not completely understood. There are mechanical theories that suggest symptomatic FAI is linked to sagittal pelvic morphology and spinopelvic-femoral dynamics. The aim of this study is to evaluate the relation of sagittal pelvic morphology and orientation to radiographic signs of FAI. Additionally, we test whether the relation between FAI and spinopelvic parameters differs in osteoarthritic hips.

METHODS

From a prospective, observational cohort study, 1002 patients between 45 and 65 years old with a first episode of knee or hip pain were followed for 8 years. All patients who had lateral lumbar radiographs and clinical and radiographic follow-up of the hips were included in the present study. Range of internal rotation of the hip as well as radiographic signs of FAI (alpha and Wiberg angle) and presence of hip osteoarthritis (Kellgren and Lawrence) were systematically measured at baseline. Pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS)) were measured at 8-year follow-up. Associations between PI, PT, SS and FAI parameters were tested using generalised estimating equations.

RESULTS

421 subjects, 842 hips, were included. No significant relations between PI, PT or SS and alpha or Wiberg angle were found. Comparison of hips with and without radiological sign(s) of FAI showed no differences in PI, PT or SS. There was no relation between range of internal rotation of the hip and spinopelvic parameters.

CONCLUSION

Sagittal pelvic morphology and orientation are not related to the presence of radiological signs of FAI in this study population.

Effects of Hip Pain Diagnostic Labels and Their Explanations on Beliefs About Hip Pain and How to Manage It: An Online Randomized Controlled Trial

OBJECTIVES: To compare the effects of diagnostic labels and their explanations on people's beliefs about managing hip pain. DESIGN: Online randomized controlled trial involving 626 participants. METHODS: Participants aged ≥45 years with and without hip pain considered a hypothetical scenario (initial doctor consultation for hip pain). They were randomized to receive a diagnostic label and explanation of (1) hip osteoarthritis, (2) persistent hip pain, or (3) hip degeneration. Primary outcomes were the beliefs (1) exercise would damage the hip and (2) surgery is necessary at some stage (scales, 0 = definitely would not/unnecessary, 10 = definitely would/necessary). Secondary outcomes included beliefs about other treatments and care providers. RESULTS: Compared to hip degeneration, participants who were allocated to hip osteoarthritis and persistent hip pain believed exercise was less damaging (mean difference -1.3 [95% CI: -1.9, -0.7] and -1.8 [-2.3, -1.2], respectively) and surgery less necessary (-1.5 [-2.1, -1.0] and -2.2 [-2.7, -1.6], respectively). Compared to hip osteoarthritis, participants who were allocated to persistent hip pain believed surgery was less necessary (-0.7 [-1.2, -0.1]), but not that exercise was less damaging (-0.5 [-1.1, 0.1]). Compared to hip degeneration, participants who were allocated to hip osteoarthritis and persistent hip pain were less concerned about their hip and believed exercise and care from an exercise and sports physician, rheumatologist, or physiotherapist would be more helpful, and care from an orthopaedic surgeon less helpful. CONCLUSIONS: People who were allocated a diagnostic label and explanation of hip osteoarthritis or persistent hip pain believed exercise was less damaging and surgery less necessary for a hip problem than hip degeneration. J Orthop Sports Phys Ther 2023;53(11):673-684. Epub 5 October 2023. doi:10.2519/jospt.2023.11984.

Sex-specific bone and muscular morphological features in ischiofemoral impingement: A three-dimensional study

The study aimed to investigate how hip bone and muscular morphology features differ between ischiofemoral impingement (IFI) patients and healthy subjects among males and females. Three-dimensional models were reconstructed based on magnetic resonance imaging images from IFI patients and healthy subjects of different sexes. Bone morphological parameters and the cross-sectional area of the hip abductors were measured. The diameter and angle of the pelvis were compared between patients and healthy subjects. Bone parameters of the hip and cross-sectional area of the hip abductors were compared between affected and healthy hips. The comparison results of some parameters were significant for females but not males. For females, the comparison results of pelvis parameters showed that the anteroposterior diameter of the pelvic inlet (p = 0.001) and intertuberous distance (p < 0.001) were both larger in IFI patients than in healthy subjects. Additionally, the comparison results of hip parameters showed that the neck shaft angle (p < 0.001) and the cross-sectional area of the gluteus medius (p < 0.001) and gluteus minimus (p = 0.005) were smaller, while the cross-sectional area of the tensor fasciae latae (p < 0.001) was significantly larger in affected hips. Morphological changes in IFI patients demonstrated sexual dimorphism, including bone and muscular morphology. Differences in the anteroposterior diameter of the pelvic inlet, intertuberous distance, neck shaft angle, gluteus medius, and gluteus minimus may explain why females are more susceptible to IFI.

Utility of 3D Planning Software in Understanding Residual Proximal Femoral Deformity for Planning of Revision Hip Arthroscopy

BACKGROUND

During the early evolution of femoroacetabular impingement (FAI) treatment, undercorrection of femoral deformity was a leading cause of hip arthroscopy failures. As the pendulum has swung, overresection of femoral deformity has increased in prevalence as a cause of persistent hip pain after arthroscopy. Computed tomography (CT) scans are increasingly being used in hip arthroscopy for preoperative planning purposes and may allow for improved 3-dimensional (3D) assessment of complex femoral deformities after previous femoroplasty.

PURPOSE

To assess whether CT scans provide additional utility over standard radiographs in understanding proximal femoral morphology in patients being evaluated for revision hip arthroscopy after previous femoroplasty in the setting of FAI.

STUDY DESIGN

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

METHODS

Preoperative CT scans and standard radiographs were obtained in 80 patients who underwent revision hip arthroscopy for FAI. The anteroposterior and Dunn radiographic views were used to assess patients for residual proximal femoral deformity and were compared with the CT scan views using a commercially available software program. Determinations of underresection were made using alpha angle, while overresection was determined according to a previously described technique. Chi-square tests were performed to determine statistical significance between radiographic and CT classifications of overresection, underresection, and concomitant over- and underresection. A kappa value was calculated to determine the agreement between measurements on the radiographs and CT scans.

RESULTS

There were 30 patients (37.5%) for whom the CT scans revealed information about femoral morphology that was not detected on the radiographs. The kappa value of agreement was 0.28 between CT and radiographic measurements. Underresected cams were detected in 30 patients (37.5%) on CT scans versus 17 patients (21.3%) on radiographs (P = .024). Overresected cams were detected in 31 patients (38.8%) on CT scans versus 14 patients (17.5%) on radiographs (P = .0049). Concomitant areas of under- and overresection were detected in 12 patients (15.0%) on CT scans versus 3 patients (3.8%) on radiographs (P = .027).

CONCLUSION

CT scans with 3D planning software may be more sensitive than traditional radiographic views at detecting aberrant proximal femoral anatomy in the setting of failed FAI surgery. The use of 3D planning software may be considered as an adjunctive tool to better understand complex deformity in the proximal femur for the planning of revision hip arthroscopy.

Intramuscular innervation of the tensor fasciae latae: Application to total hip arthroplasty

The aims of this study were to clarify the extra- and intramuscular branching patterns of the tensor fasciae latae (TFL) with reference to surface landmarks on the thigh and to thus suggest a safe approach for total hip arthroplasty. Sixteen fixed and four fresh cadavers were dissected and subjected to the modified Sihler's staining method to reveal the extra- and intramuscular innervation patterns, and the findings were matched with surface landmarks. The landmarks were measured from the anterior superior iliac spine (ASIS) to the patella and divided into 20 parts along the total length. The average vertical length of the TFL was 15.92 ± 1.61 cm, which was 38.79 ± 2.73% when converted to a percentage. The entry point of the superior gluteal nerve (SGN) was an average of 6.87 ± 1.26 cm (16.71 ± 2.55%) from the ASIS. In all cases, the SGN entered parts 3-5 (10.1%-25%). As the intramuscular nerve branches traveled distally, they had a tendency to innervate more deeply and inferiorly. In all cases, the main SGN branches were intramuscularly distributed in parts 4 and 5 (15.1%-25%). Most tiny SGN branches were found inferiorly in parts 6 and 7 (25.1%-35%). In three of 10 cases, very tiny SGN branches were observed in part 8 (35.1%-38.79%). We did not observe SGN branches in parts 1-3 (0%-15%). When information on the extra- and intramuscular nerve distributions was combined, we found that the nerves were concentrated in parts 3-5 (10.1%-25%). We propose that damage to the SGN can be prevented if parts 3-5 (10.1%-25%) are avoided during surgical treatment, particularly during the approach and incision.

HipScreen mobile app for the measurement of hip migration percentage in children with cerebral palsy: Accuracy, reliability, and discriminatory ability

AIM

To assess the accuracy, reliability, and discriminatory ability of a mobile app for measurement of migration percentage in hip surveillance radiographs of children with cerebral palsy (CP).

METHOD

The free mobile app HipScreen (www.hipscreen.org) was utilized by a diverse group of users to measure the migration percentage of 40 hips at two time points after completing an online tutorial and competency test. The mean absolute error (MAE) was calculated against the reference standard obtained on a radiology workstation. Statistical analyses included linear regression, intraclass correlation coefficient (ICC), and area under receiver-operating characteristic curve (AUC).

RESULTS

Thirty-seven users completed the study, with 30 having a healthcare professional background, but only 15 with x-ray interpretation expertise. The overall MAE of migration percentage measurement using the HipScreen app was 5.72% (95% confidence interval [CI]: 5.38-6.06), with good reliability between time points (ICC = 0.83). With a migration percentage less than 30% considered as a positive case, the HipScreen app had a sensitivity of 94% (95% CI: 87-97), specificity of 66% (95% CI: 61-77), and an AUC of 0.92 (95% CI: 0.88-0.96).

INTERPRETATION

Users from a broad range of backgrounds can utilize the HipScreen app to measure hip surveillance radiographs with clinically acceptable accuracy, reliability, and discriminatory ability.

WHAT THIS PAPER ADDS

The HipScreen app can accurately and reliably measure migration percentage. As a screening tool, HipScreen has excellent sensitivity and discriminatory ability. A broad range of HipScreen users achieve clinically acceptable performance.

The correlation between transient osteoporosis of the hip and pregnancy: A review

Transient osteoporosis of the hip is indubitably a comparatively infrequent entity affecting both men and women worldwide. Its occurrence in the course of pregnancy, specifically in the third trimester, and lactation are of paramount concernment. The exact association between transient hip osteoporosis and pregnancy is precarious. Etiology and potential pathophysiological mechanisms behind this correlation are still to be utterly defined. Magnetic resonance imaging is highly regarded as the gold standard imaging method for assiduous assessment of this disorder. Physicians of copious medical specialties should practice scrupulous techniques for early and pertinent diagnosis when pregnant women are presented with persistent hip pain, as differential diagnosis with femoral head avascular necrosis can be exceedingly arduous. Treatment is predominantly conservative with protected weight-bearing and analgesic medication in the first line of management. In terms of prognosis, the disease ordinarily resolves spontaneously after a few months. Further research is required in order to elucidate the ambiguity surrounding the establishment of globally approved diagnosis and treatment guidelines for pregnancy-associated transient hip osteoporosis. This paper aims to accentuate the significance of this particular disorder by providing a succinct review of the existing literature, augmenting clinicians' knowledge about the features of pregnancy-related transient proximal femur osteoporosis.

Is there hip muscle weakness in adults with chronic non-specific low back pain? A cross-sectional study

BACKGROUND

Patients with chronic low back pain may present changes in hip muscles. However, there is still limited and controversial evidence of the association between hip muscle weakness and chronic low back pain and whether this weakness can be assessed with functional tests. The purpose of this study was to assess whether there is hip muscle weakness in patients with non-specific chronic low back pain and whether there is an association between the positive Trendelenburg and Step-Down tests and hip muscle strength.

METHODS

This cross-sectional study included 40 patients with chronic low back pain and 40 healthy participants, assessed in an outpatient clinic in Vitória, Espírito Santo, Brazil. Muscle strength was measured for the hip abductors, adductors, extensors, internal rotators, and external rotators using isometric manual dynamometry and functional stability was measured by the Trendelenburg and Step-Down tests. Muscle strength was compared using the t test for independent samples and the chi-square test. The association between the tests and strength was performed using a binary logistic regression analysis.

RESULTS

Healthy participants showed a statistically significant greater muscle strength for the right hip abductors (mean difference [MD]: 28.1%, 95% confidence interval [CI]: 9.4 to 46.9), right adductors (MD: 18.7%, 95% CI: 6.2 to 31.2), right internal rotators (MD: 8.7%, 95% CI: 1.5 to 15.8), right extensors (MD: 21.1%, 95% CI: 6.2 to 31.2), left abductors (MD: 30.4%, 95% CI: 11.9 to 49), left adductors (MD: 18.4%, 95% CI: 3.7 to 33.2), and left extensors (MD: 21.6%, 95% CI: 6.6 to 36.5). There was no difference between groups for the positive functional tests, and there was no association between the tests and hip muscle strength.

CONCLUSION

Patients with chronic low back pain tend to have hip abductors, adductors, and extensors weakness. Furthermore, the functional tests should not be associated to hip muscle strength in patients with chronic low back pain.

Thigh-hip ratio is significantly associated with all-cause mortality among Japanese community-dwelling men

Anthropometric evaluation is a simple yet essential indicator of muscle and fat mass when studying life prognosis in aging. This study aimed to investigate the contributions of anthropometric measurements, independent of body mass index, to measures of all-cause mortality. We examined data for 1,704 participants from the 2014 Nomura Cohort Study who attended follow-ups for the subsequent eight years (follow-up rate: 93.0%). Of these, 765 were male (aged 69 ± 11 years) and 939 were female (aged 69 ± 9 years). The Japanese Basic Resident Registry provided data on adjusted relative hazards for all-cause mortality. The data were subjected to a Cox regression analysis, wherein the time variable was age and the risk factors were gender, age, anthropometric index, smoking habits, drinking habits, exercise habits, cardiovascular history, hypertension, lipid levels, diabetes, renal function, and serum uric acid. Of the total number of participants, 158 (9.3%) were confirmed to have died, and of these, 92 were male (12.0% of all male participants) and 66 were female (7.0% of all female participants). The multivariable Cox regression analysis revealed that a smaller thigh-hip ratio predicted eight-year all-cause mortality in male participants, but only baseline body mass index was associated with all-cause mortality in female participants. Thigh-hip ratio is a useful predictor of death in Japanese community-dwelling men.

Hip Pain and Physical Therapy Nonarthritic Hip Pain: What Is It? What Should I Do About It? How Do I Get Back to My Regular Activities?

Hip pain can have many causes, both arthritic and non-arthritic. Experts in managing hip pain developed a guideline to help rehabilitation clinicians help you understand more about hip pain. Here we explain what physical therapy might offer you if you have hip pain and arthritis has been ruled out. You will find out about some of the leg strength and balance tests your physical therapist might ask you to do, and exercises to help alleviate your hip pain and improve your strength, movement and balance.J Orthop Sports Phys Ther 2023;53(10):643-644. doi:10.2519/jospt.2023.0506.

Team Approach: Hip Preservation Surgery

The evaluation and treatment of adolescents and young adults with hip pain has seen tremendous growth over the past 20 years. Labral tears are well established as a common cause of hip pain but often occur because of underlying bony abnormalities. Femoroacetabular impingement (FAI) and acetabular dysplasia are now well-established causes of hip osteoarthritis and are increasingly treated in the prearthritic stage in hopes of improving symptoms and prolonging the longevity of the native hip. Beyond FAI and acetabular dysplasia, this patient population can present with a complex and variable group of underlying conditions that need to be taken into account. Expertise in the conservative management of this population, including physical therapy, is valuable to maximize the success. Preoperative, surgical, and postoperative decision-making and care in this population is complex and evolving. A comprehensive, multidisciplinary approach to the care of this patient population has been used for over 20 years by our institution with great success. The purpose of this article is to review the "team-based approach" necessary for successful management of the spectrum of adolescent and young adult hip disorders.

Electromyographic analysis of trunk and hip muscles during Yoga poses prescribed for treating chronic low back pain

Yoga is effective for the management of chronic low back pain as it improves muscle strength and endurance. The objective of the current study was to assess trunk and hip muscle activation during Yoga poses usually prescribed for patients with chronic LBP. The study included 22 healthy Yoga trained subjects (mean age: 24.4 ± 2.6 years; 16 females, 6 males). The testing involved collecting surface electromyography data from Rectus Abdominis (RA) and Transverse Abdominis (TA), Gluteus Medius (GM), and Erector Spinae (ES) as subjects attained and held 16 different Yoga poses in standing, kneeling, supine, or prone positions in random order. The signal of each muscle was processed and normalized to its maximum voluntary isometric contraction (MVC). Statistical comparisons were made across selected poses and phases (attaining and holding) for each muscle using repeated-measures ANOVA. The data was also descriptively analyzed for sorting muscle activity. The activation of trunk flexors was significantly higher during boat pose (>50% MVC) followed by plank pose (∼30% MVC), activation of ES was significantly higher during reverse boat (41.7% ± 3.3 MVC) as compared to bow, snake, backward-sway, and warrior poses. The GM activation was significantly less in standing poses than during side-lying and Tiger poses (32-42% MVC). The cat-camel, kneeling camel, downward dog, backward-sway, swaying-palm tree, and warrior poses activated all tested muscles fairly (<20% MVC). The study helps the grading of Yoga positions according to the challenge imposed. The challenging poses may be used to develop graded rehabilitation programs to improve muscle strength/endurance.

The Effect Of Physical Therapy Intervention After Cerebellar Resection

A variety of diseases, including gait ataxia, lack of coordination, diminished dexterity, and unsteady posture, can be brought on by cerebellar dysfunction. This case study looks into how a physical therapy program affected a 40-year-old patient's dynamic balance after cerebellar tumour surgery. The patient complained of losing his balance and having uncoordinated motions on the left side of the body. The Timed Up and Go (TUG) test was used to gauge how the Frenkel coordination exercises and balance training affected dynamic balance following cerebellar tumour removal. The patient's muscle strength in the left-side hip extensors, abductors and adductors, knee flexors and extensors, as well as the left-side shoulder, elbow, and wrist flexion and extension, significantly improved.

A case report with literature review

AIM

Avascular necrosis (AVN) or osteonecrosis is characterized by death of bone tissue due to endothelial damage and vascular abnormality. Coronavirus can induce endothelial damage and abnormal blood clotting, so that COVID-19 is known as a vascular disease. We aim to evaluate the relationship between AVN and COVID-19.

CASE

Here we present a 39-year old man with severe COVID-19 and corticosteroid consumption who developed late onset AVN of both hips 20 month after COVID-19.

CONCLUSION

An awareness of the possible osteonecrosis for all physicians dealing with patients with musculoskeletal problems following COVID-19 is necessary.

Pregnancy, Hip Pain, and Total Hip Replacement

➤ Young women who are 15 to 45 years of age and undergo total hip replacements are at increased risk for revision compared with women >75 years of age.➤ Among women of childbearing age with a total hip replacement, 12% to 17% will later have at least 1 pregnancy.➤ Young women who undergo total hip replacement do not have an increased risk of pregnancy complications.➤ Of the 60% of women who experienced pain with a total hip replacement during pregnancy, 21% had persisting pain, and 4% reported the pain as severe.➤ Women who have a total hip replacement and later experience pregnancy and childbirth have no increased risk of pregnancy complications or increased revision rates; there was no effect of the mode of delivery on revision rates or complications including fracture, dislocation, or loosening, according to the limited studies available.

Validation of a musculoskeletal model to investigate hip joint mechanics in response to dynamic multiplanar tasks

Existing hip-focused musculoskeletal (MSK) models are limited by the hip range of motion, hip musculature detail, or have only been qualitatively validated. The purposes of this study were to: i) modify the existing 2396Hip MSK model to simulate dynamic tasks with multiplanar hip joint motion; and ii) validate the modified MSK model quantitatively against experimental data. Experimental data was collected from five healthy adults (age = 25 [6] years, two females) during eight movement tasks. The motion and ground reaction force data were input into the MSK modeling software OpenSim to calculate muscle activations and hip contact forces (HCFs). The HCFs were compared to experimental HCFs previously measured in total hip arthroplasty (THA) patients using instrumented hip prostheses. A gait simulation was performed using data from one THA patient to directly assess the model's accuracy in estimating HCFs. The young adults' modeled and experimental muscle activations for seven muscles were compared using a cross-correlation function. The model only overestimated the peak resultant HCFs by 0.06-0.08 N/BW compared to the experimentally measured HCFs of the THA patient. The young adults' HCFs were over two standard deviations higher than previously measured in the THA patients, which is likely a result of different movement patterns. The correlation coefficients indicated strong correlations between experimental and modeled muscle activations in 50 of the 56 comparisons. The results of this study suggest the new MSK model is an appropriate method to quantify HCFs and muscle activations in response to dynamic, multiplanar tasks among young, healthy adults.

Comparison of In-service Reduced vs. Full Torso Coverage Armor for Females

INTRODUCTION

Body armor and torso-borne equipment are critical to the survivability and operational effectiveness of a soldier. Historically, in-service designs have been predominantly designed for males or unisex, which may be disadvantageous for females who are shaped differently and, on average, smaller in stature and mass than their male counterparts. This study assesses the biomechanical and performance impact of two Canadian in-service armors and fighting load conditions on females.

MATERIALS AND METHODS

Four tasks (i.e., range of motion, treadmill march [×2], and a wall obstacle) were performed in a Baseline condition and two in-service torso-borne equipment conditions; the full torso coverage (FTC) condition has full upper torso soft armor with the fighting load carried in a separate vest, while the reduced coverage (RC) has a plate carrier with fighting load integrated into the armor carrier, bulk positioned higher, and less torso coverage. Both used identical combat loads and front and back armor plates. Trunk range of motion, march lower limb kinematics, march shoulder and hip skin pressures, perceived discomfort after the march, and time to traverse a wall obstacle were captured. Data were collected to assess the biomechanics and usability of the systems for eight females, representative of military recruits. Linear mixed-effects models were created, and analysis of variances (ANOVAs) were then performed on all the outcome measures (P < .05). Tukey's post-hoc procedures were performed when appropriate (P < .05).

RESULTS

There were significant differences between the RC and FTC for the sit and reach test (P < .001), lateral bend test (P < .001), and wall traverse time (P < .01). In all cases, the RC outperformed FTC. There were no differences between the two in-service conditions with respect to hip, knee, and ankle flexion/extension. The RC average skin pressure was higher than the FTC at the left and right shoulders by 103% and 79%, respectively, and peak skin pressure at the left shoulder by 75%. Both in-service conditions showed decrements in performance from Baseline for sit and reach (P < .001), lateral bend (P < .001), and peak hip and knee flexion (P < .01) with the FTC showing decreases in trunk rotation (P < .001) and wall traverse time (P < .01).

CONCLUSIONS

Improved outcomes for the RC can be attributed to design differences. The lower placement of bulk in FTC may act as a physical barrier during range of motion tasks and the wall obstacle. The presence of shoulder caps on FTC provides another physical barrier that likely impedes full movement through the arms and shoulders. While the narrower shoulder straps of the RC remove the barrier, it causes more concentrated skin pressures on the shoulder that can lead to injury. The results suggest that the RC offers a potential for increased operational effectiveness in females (and potentially for males) compared to the FTC system. Shoulder pressure, an important predictor of discomfort and injury, is the only measure for which FTC outperformed the RC. Future torso-borne equipment designs targeting this outcome measure could help increase the effectiveness of the RC and other similar systems that reduce torso coverage, though survivability implications must also be considered.

Investigation of the association of weight loss with radiographic hip osteoarthritis in older community-dwelling female adults

OBJECTIVE

Most guidelines recommending weight loss for hip osteoarthritis are based on research on knee osteoarthritis. Prior studies found no association between weight loss and hip osteoarthritis, but no previous studies have targeted older adults. Therefore, we aimed to determine whether there is any clear benefit of weight loss for radiographic hip osteoarthritis in older adults because weight loss is associated with health risks in older adults.

METHODS

We used data from white female participants aged ≥65 years from the Study of Osteoporotic Fractures. Our exposure of interest was weight change from baseline to follow-up at 8 years. Our outcomes were the development of radiographic hip osteoarthritis (RHOA) and the progression of RHOA over 8 years. Generalized estimating equations (clustering of 2 hips per participant) were used to investigate the association between exposure and outcomes adjusted for major covariates.

RESULTS

There was a total of 11,018 hips from 5509 participants. There was no associated benefit of weight loss for either of our outcomes. The odds ratios (95% confidence intervals) for the development and progression of RHOA were 0.99 (0.92-1.07) and 0.97 (0.86-1.09) for each 5% weight loss, respectively. The results were consistent in sensitivity analyses where participants were limited to those who reported trying to lose weight and who also had a body mass index in the overweight or obese range.

CONCLUSION

Our findings suggest no associated benefit of weight loss in older female adults in the structure of the hip joint as assessed by radiography.

Weak gluteus maximus and weak iliopsoas with normal gluteus maximus: Two complementary new signs to diagnose lower limb functional weakness

BACKGROUND AND PURPOSE

The diagnosis of functional neurological disorder should be actively made based on the neurological signs. We described two new complementary signs to diagnose functional weakness of the lower limb, "weak gluteus maximus (weak GM)" and "weak Iliopsoas with normal gluteus maximus (weak iliopsoas with normal GM)," and tested their validity.

METHODS

The tests comprised Medical Research Council (MRC) examinations of the iliopsoas and GM in the supine position. We retrospectively enrolled patients with functional weakness (FW) or structural weakness (SW) who presented with weakness of either iliopsoas or GM, or both. Weak GM means that the MRC score of GM is 4 or less. Its complementary sign, weak ilopsoas with normal GM, means that the MRC score of ilopsoas is 4 or less, whereas that of GM is 5.

RESULTS

Thirty-one patients with FW and 72 patients with SW were enrolled. The weak GM sign was positive in all 31 patients with FW and in 11 patients with SW, that is, 100% sensitivity and 85% specificity. Therefore, the complementary sign, weak iliopsoas with normal GM, was 100% specific for SW.

DISCUSSION

Although 100% should be discounted considering limitations of this study, these signs will likely be helpful in differentiating between FW and SW in the general neurology setting. Downward pressing of the lower limb to the bed in the supine position is interpreted by the patient as an active movement exerted with an effort and might be preferentially impaired in FW.

The Significance of Isolated Hip Click as a Sign of DDH: Implications on Referral Guidelines

BACKGROUND

The clinical significance of an isolated hip click remains unclear. The rates of developmental dysplasia of the hip (DDH) in those referred for hip click vary from 0% to 28%. The purpose of this study was to evaluate the rate of DDH in patients prospectively referred for isolated hip click.

METHODS

We prospectively enrolled patients referred to a single pediatric orthopaedic center with concern for DDH secondary to isolated hip click felt by the pediatrician on examination. Patients with known sonographic abnormalities or risk factors for DDH (breech presentation or positive family history) were excluded. Ultrasounds were obtained upon initial presentation and defined as abnormal if alpha angle <60 degrees and/or femoral head coverage (FHC) <50%. Mild dysplasia, analogous to Graf IIa physiological immaturity, was defined as alpha angle 50<α<60 and/or <50% FHC in a patient <3 months age. Severe dysplasia was defined as ≤33% FHC, which has been proposed to be sonographically consistent with a hip dislocation.

RESULTS

Two hundred fifty-five children were referred for isolated hip click. One hundred eighty-nine patients (74%) had normal ultrasound whereas 66 patients (26%) had sonographic abnormalities (mean age 6.5±6.2 wk at initial ultrasound). Fifty patients (19.6%) demonstrated physiological immaturity, 3 patients (1.2%) demonstrated moderate sonographic dysplasia, and 13 patients (5.1%) had sonographic findings consistent with severe dysplasia or dislocated hip. Hips with severe dysplasia were younger than the remaining population (2.8±2.4 wk vs. 6.6±6.2 wk, P <0.001) with no difference in sex distribution ( P =0.07) or first-born birth order ( P =0.36). For those with sonographic abnormality, 18 (27%) patients were treated with Pavlik harness, 1 (2%) was treated with abduction orthosis, and the remainder (71%) were observed for resolution of physiological immaturity.

CONCLUSIONS

Infants with isolated hip click identified by their pediatrician may have higher rates of dysplasia than previously reported. We recommend screening ultrasound and/or orthopaedic referral for all infants with isolated hip click.

LEVEL OF EVIDENCE

Level II-prospective prognostic study.

Hip Strength Profiling of Ice Hockey Athletes Across Various Joint-Specific Angles: Monitoring and Injury Implications

ABSTRACT

Secomb, JL, Kelly, M, and Dascombe, BJ. Hip strength profiling of ice hockey athletes across various joint-specific angles: monitoring and injury implications. J Strength Cond Res 37(7): e422-e429, 2023-The purpose of this research was to compare the hip adduction and abduction relative strength, adduction-to-abduction strength ratio (ADD:ABD), and interlimb asymmetries of ice hockey athletes between the typically used bilateral position and 3 unilateral positions in joint-specific angles (0°, 25°, and 50° of hip abduction) relevant to an ice hockey stride. A secondary purpose was to explore any relationships between these measures and hip and groin noncontact injuries, and self-reported pain and disability. Twenty-five semiprofessional male ice hockey athletes (26.7 ± 6.7 years) were assessed for hip abduction range of motion (ROM), hip adduction and abduction relative strength, and completed the Copenhagen Hip and Groin Outcome Score (HAGOS) questionnaire. Within-subjects repeated-measures analysis of variance revealed a significant effect for the assessment position for adduction ( F1,24 = 52.4, p < 0.01) and abduction relative strength ( F1,24 = 152.1, p < 0.01), ADD:ABD ( F1,24 = 38.9, p < 0.01), and the interlimb asymmetries for each of these variables ( F1,24 = 9.8-12.3; p < 0.01), with large strength differences observed between the bilateral assessment and all unilateral assessment positions for adduction and abduction relative strength. In addition, 4 athletes experienced a noncontact hip or groin injury within 1 month after testing, and when compared with the rest of the cohort ( n = 21) with Welch's t -tests, demonstrated significantly reduced hip abduction ROM (mean difference [MD] = -8.4 ± 2.5°; p < 0.01), sport subscale score for the HAGOS questionnaire (MD = -33.9 ± 7.1; p < 0.01), and a decline in hip adduction relative strength in the unilateral position of 50° compared with the position of 25° hip abduction (MD = -13.4 ± 3.8; p = 0.04). These results suggest that practitioners working with ice hockey athletes may benefit from profiling hip strength in these unilateral joint-specific angle positions because they provide an evidence base to determine the hip strength needs of ice hockey athletes in positions associated with skating performance and noncontact hip and groin injury mechanisms (between 25° and 50° of hip abduction).

Development of acetabular retroversion in LCPD hips-an observational radiographic study from early stage to healing

BACKGROUND

Acetabular retroversion is observed frequently in healed Legg-Calvé-Perthes disease (LCPD). Currently, it is unknown at which stage and with what prevalence retroversion occurs because in non-ossified hips, retroversion cannot be measured with standard radiographic parameters.

METHODS

In a retrospective, observational study; we examined pelvic radiographs in children with LCPD the time point of occurrence of acetabular retroversion and calculated predictive factors for retroversion. Between 2004 and 2017, we included 55 children with a mean age of 5.7 ± 2.4 years at diagnosis. The mean radiographic follow-up was 7.0 ± 4.4 years. We used two new radiographic parameters which allow assessment of acetabular version in non-ossified hips: the pelvic width index and the ilioischial angle. They are based on the fact that the pelvic morphology differs depending on the acetabular version. These parameters were compared among the four Waldenström stages and to the contralateral side. Logistic regression analysis was performed to determine predictive factors for acetabular retroversion.

RESULTS

Both parameters differed significantly among the stages of Waldenström (p < 0.003 und 0.038, respectively). A more retroverted acetabulum was found in stage II and III (prevalence ranging from 54 to 56%) compared to stage I and IV (prevalence ranging from 23 to 39%). In hips of the contralateral side without LCPD, the prevalence of acetabular retroversion was 0% in all stages for both parameters. Predictive factors for retroversion were younger age at stage II and IV, collapse of the lateral pillar in stage II or a non-dysplastic hip.

CONCLUSIONS

This is the first study evaluating acetabular version in children with LCPD from early stage to healing. In the developing hip, LCPD may result in acetabular retroversion and is most prevalent in the fragmentation (stage II) and early healing stage (stage III). Partial correction of acetabular retroversion can occur after healing. This has a potential clinical impact on the timing and type of surgical correction, especially in pelvic osteotomies for correction of acetabular version.

LEVEL OF EVIDENCE

Level III, retrospective observational study.

Intra and interrater reliability for lower limb flexibility assessment using photogrammetry

INTRODUCTION

Photogrammetry represents an advancement in the flexibility evaluation, and although it was highly explored for postural assessment, there is a scarcity of studies analyzing lower limb angular measurements using it. The purpose of this study is to verify the reliability of intrarater and interrarater photogrammetry in assessing lower limb flexibility.

METHODS

This was a randomized cross-sectional observational study with test-retest design and a two-day interval. Thirty healthy, physically active adults were included. Three novice raters assessed the participants through flexibility tests of iliopsoas, hamstring, quadriceps and gastrocnemius on two occasions, and independently analyzed the captured images to establish reliability. Intraclass correlation coefficient (ICC), standard error of measurement (SEM), and minimal detectable change (MDC) were calculated.

RESULTS

Intrarater reliability was excellent for iliopsoas (ICC = 0.96; SEM = 1.4; MDC = 3.8), hamstring (ICC = 0.99; SEM = 1.1; MDC = 3.1), quadriceps (ICC = 0.99; SEM = 0.8; MDC = 2.3) and gastrocnemius (ICC = 0.98; SEM = 0.9; MDC = 2.5). Interrater reliability was excellent for iliopsoas (ICC = 0.94; SEM = 1.7; MDC = 4.6) and gastrocnemius (ICC = 0.91; SEM = 2.1; MDC = 5.8), but good for hamstring (ICC = 0.90; SEM = 2.8; MDC = 7.9) and quadriceps (ICC = 0.85; SEM = 3.0; MDC = 8.3).

CONCLUSIONS

The excellent intrarater and good to excellent interrater reliability suggest that photogrammetry assessment of lower limb flexibility by novice raters is reliable. However, clinicians should consider the higher threshold of range of motion change necessary to outweigh measurement error due to interrater variability.