Hip Rotation Research Articles

Body Mass Index is Related to Femoral Anteversion, Hip Rotation During Gait, and Passive Hip Range of Motion in Children and Adolescents.

Overweight and obesity are major global health issues, often linked to orthopaedic problems, skeletal malalignments, and altered gait biomechanics. However, skeletal and biomechanical adaptions in the transverse plane remain underexplored. Therefore, this study aimed to investigate the relationship between body mass index (BMI) and variables describing lower extremity torsional profiles, hip rotation mobility, and transverse plane gait characteristics in children and adolescents. Acetabular and femoral anteversion, tibial torsion (measured through computed tomography), hip and knee rotation, and foot progression angles during the stance phase of gait (measured by 3D gait analysis), as well as passive hip rotation range of motion (evaluated as the midpoint of hip rotation in clinical examination), were retrospectively analyzed in 122 children and adolescents. Correlations between all variables and logit-transformed BMI percentiles were calculated. Moderate correlations were found between BMI percentile and hip rotation during the stance phase (r=-0.68, P<0.001), the passive midpoint of hip rotation (r=-0.51, P<0.001), and femoral anteversion (r=-0.50, P<0.001). Small correlations were observed for acetabular anteversion (r=-0.36, P<0.001), knee rotation during stance phase (r=0.34, P<0.001), and foot progression angle during stance phase (r=-0.31, P<0.001). Tibial torsion showed a nonsignificant negligible relationship with BMI percentile (r=-0.26, P=0.004). BMI percentile was positively correlated with external hip rotation during the stance phase of gait and passive external hip rotation, and negatively correlated with femoral anteversion. These findings suggest abnormal body weight is associated with static and dynamic biomechanical alterations. Therefore, weight management should be considered in orthopaedic assessments and treatment planning for children and adolescents.

Comparison of gait deviation index (GDI) and gait variability index (GVI) measured by marker-based and markerless motion capture systems in children with cerebral palsy (CP)

BackgroundThe Gait Deviation Index (GDI) is a metric clinicians use to assess overall gait pathology in children with cerebral palsy (CP) by comparing kinematic data to a normative sample. The Gait Variability Index (GVI) is a related metric that quantifies the variability in spatio-temporal variables during gait. The GDI and GVI have been verified using marker-based motion capture approaches, but video-based markerless motion capture has not been compared using these tools in children with CP. Research questionDo GDI and GVI scores differ when measured using markerlessTheia3D and a marker-based approach between the more and less affected legs in children with CP? MethodsFifteen children with CP (GMFCS levels I-IV) and 24 typically developing children aged 6–18 years were recruited for this study. Overground walking was performed at a self-selected pace while the pelvis and lower limb kinematics were simultaneously recorded using both motion capture systems. Differences in GDI and GVI scores when considering the effect of system and limb impairment were analyzed using two-way repeated-measures ANOVAs. ResultsGDI scores were 6.9 points lower (p < 0.05) when measured using Theia3D compared to the marker-based approach and 6.8 points lower (p < 0.05) in the more affected limbs than in the less affected limbs. These GDI score differences are considered clinically significant. No differences were identified in GVI scores between systems or limb impairment. Differences in kinematic measurements were found in children with CP, including pelvic tilt, hip flexion/extension, hip rotation, and foot progression angle, where root mean square differences between systems exceeded 10°. SignificanceTheia3D can adequately measure variability in spatio-temporal gait parameters for quantifying GVI scores in children with CP compared to the marker-based approach. However, caution is needed when quantifying lower limb kinematics and interpreting GDI and GVI scores using Theia3D in children with CP.

3D-Printed Prosthesis with an Articular Interface for Anatomical Acetabular Reconstruction After Type I + II (+ III) Internal Hemipelvectomy

Background: Pelvic reconstruction after type I + II (or type I + II + III) internal hemipelvectomy with extensive ilium removal is a great challenge. In an attempt to anatomically reconstruct the hip rotation center (HRC) and achieve a low mechanical failure rate, a custom-made, 3D-printed prosthesis with a porous articular interface was developed. The aim of this study was to investigate the clinical outcomes of patients treated with this prosthesis. Methods: This retrospective cohort study included 28 patients with type I + II (+ III) internal hemipelvectomy through the articular interface of the sacroiliac joint and managed with a prosthesis at a single center between August 2016 and August 2021. Complications and oncological outcomes were analyzed. The position of the reconstructed HRC was assessed and lower-limb function was evaluated. Biomechanical analyses of different fixation modes of the prosthesis were conducted using finite element analysis. Results: The displacement distance of the HRC from preoperatively to postoperatively was a mean (and standard deviation) of 14.12 ± 8.75 mm. The rate of implant-related complications was 14.3% (4 of 28) for prosthetic breakage, 14.3% (4 of 28) for aseptic loosening, 7.1% (2 of 28) for dislocation, and 7.1% (2 of 28) for deep infection. The mean Musculoskeletal Tumor Society (MSTS)-93 score was 18.2. The aseptic loosening rate was significantly greater for prostheses fixed with 3 sacral screws (4 of 10, 40.0%) than for those fixed with 4 (0 of 10, 0%) or 5 screws (0 of 8, 0%) (p = 0.024). The prosthetic breakage rate was lower in patients who underwent lumbosacral fixation (0 of 13, 0%) than in those who did not (4 of 15, 26.7%), although the difference did not reach significance (p = 0.102). Biomechanical analyses suggested that the addition of lumbosacral fixation or increasing the number of sacral screws from 3 to 4 or 5 visibly reduced the peak stress of the sacral screws. Conclusions: The use of a 3D-printed prosthesis with an articular interface for pelvic reconstruction demonstrated stable prosthetic fixation, anatomical acetabular reconstruction, and acceptable early functional outcomes. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Improvement of the gait deviation index for spinal cord injury to broaden its applicability: the reduced gait deviation index for spinal cord injury (rSCI-GDI).

The SCI-GDI is an accurate and effective metric to summarize gait kinematics in adults with SCI. It is usually computed with the information registered with a photogrammetry system because it requires accurate information of pelvic and hip movement in the three anatomic planes, which is hard to record with simpler systems. Additionally, due to being developed from the GDI, the SCI-GDI is built upon nine joint movements selected for a pediatric population with cerebral palsy, for which the GDI was originally developed, but those nine movements are not necessarily as meaningful for adults with SCI. Nevertheless, pelvic movement and hip rotation have been proven to have low reliability even when acquired with gold-standard photogrammetry systems. Additionally, the use of photogrammetry is limited in real-life scenarios and when used with rehabilitation technologies, which limits the use of the SCI-GDI to evaluate gait in alternative scenarios to gait laboratories and to evaluate technologies for gait assistance. This research aimed to improve the SCI-GDI to broaden its applicability beyond the use of photogrammetry. An exploration of the mathematical relevance of each joint movement included in the original GDI for the performance of the metric is performed. Considering the results obtained and the clinical relevance of each of the 9 joints used to compute the SCI-GDI in the gait pattern of the SCI population, a more adaptable SCI-GDI is proposed using four joint movements that can be precisely captured with simpler systems than photogrammetry: sagittal planes of hip, knee and ankle and hip abduction/adduction. The reduced SCI-GDI (rSCI-GDI) effectively represents gait variability of adults with SCI as does the SCI-GDI, while providing more generalizable results and equivalent or stronger correlations with clinical tests validated in the population. During the derivation of the improved index, it was demonstrated that pelvic movements, hip rotation, and foot progression angle introduce high variability to the dataset of gait patterns of the adult population with SCI, but they have low relevance to characterize gait kinematics of this population. The rSCI-GDI can be calculated using the 14-feature vectorial basis included in the electronic addendum provided.

The Role of the Lead Hip in Collegiate Baseball Pitching: Implications for Ball Velocity and Upper-Extremity Joint Moments.

Hip flexibility is an important biomechanical factor for a baseball pitcher. However, there have been limited investigations into the association between upper-extremity joint stresses and ball velocity and hip flexibility, as assessed via motion patterns during the pitch. The purpose of this study was to provide a detailed kinematic description of the lead hip during the pitch and determine the association between lead hip motion and both ball velocity and the elbow varus moment. This study was a secondary analysis of the kinematic and kinetic data previously collected on 99 collegiate-level baseball pitchers using standard optoelectronic motion capture. Significant associations were noted between lead hip internal rotation and both peak ball velocity and the elbow varus moment. The data indicated that for every 10° increase in internal lead hip rotation, ball velocity increased by 0.6m/s (P < .001, r2 = .26), and the elbow varus moment increased by 5N·m (P < .001, r2 = .33). The results of this study suggested that internal hip rotation may be an important means of identifying pitchers that may be at risk for future injury.

Association Between Hip Translation and Hip Rotation and Anatomy: A Pilot Quasi-static MRI Study.

There is little known about translation of the hip and the relationship with hip rotation and morphology in asymptomatic patients. (1) Femoral head would exhibit significant translations in asymptomatic hips, (2) femoral head translations would correlate to femoral rotations, and (3) range of femoral head translations would correlate to hip morphology. Cross-sectional study; Level of evidence, 3. A total of 11 individuals (age, 23-47 years; 64% female) with asymptomatic hips underwent hip magnetic resonance imaging (MRI) in the following postures: neutral (supine), midflexion, maximum-flexion, internal rotation, internal rotation + midflexion, internal rotation + maximum-flexion, adduction, flexion-abduction-external rotation (FABER), extension, and lateral abduction. All rotations were passive. MRI-generated 3-dimensional hip models were used to quantify femoral rotations and translations. Femoral head diameter, acetabular diameter, lateral center-edge angle, alpha angle, femoral anteversion, acetabular version and inclination, and neck-shaft angle were measured from MRI. A t test was used if measured translations were statistically significant. Linear regression was used to assess the associations between translation and rotation. Pearson correlation was used to assess the relationships between hip anatomy and range of femoral head translations. In all tested positions, the femoral head translated anteriorly by 2 ± 1 mm (maximum 5 mm, P < .001), posteriorly by 1 ± 1 mm (maximum 6 mm, P < .001), superiorly by 2 ± 2 mm (maximum 7 mm, P < .001), inferiorly by 2 ± 2 mm (maximum 6 mm, P < .001), laterally by 1 ± 1 mm (maximum 4 mm, P < .001), and medially by 2 ± 1 mm (maximum 5 mm, P < .001), relative to the rested supine position. Femoral flexion was associated with posterior translation of the femoral head (P = .038). Femoral abduction was associated with medial translation of the femoral head (P = .042). Higher femoral anteversion and smaller alpha angle were associated with a higher total magnitude of femoral head translation in the anterior-posterior direction (P < .04). Smaller femoral anteversion, higher acetabular inclination, smaller lateral center-edge angle, and lower neck-shaft angle were associated with a higher total magnitude of femoral head translation in the superior-inferior direction (P ≤ .03). Our study demonstrated that, during passive physiologic movement, asymptomatic hips on average translated up to 2 mm (with up to 7 mm maximum translation in some positions), which is potentially related to hip rotations and morphology. Further investigations are warranted to understand the normal and pathologic hip translations and their impact on hip function (ie, instability and impingement).

Two-year 3D gait outcomes following in-situ pinning or modified Dunn procedure in children with slipped capital femoral epiphysis

BackgroundSlipped Capital Femoral Epiphysis (SCFE) is femoral head slippage off the femoral neck through the physis occurring in children aged 8–16 years. Surgical intervention is required in all paediatric cases and there is no universal agreement on choice of surgical procedure. Research questionWhat are the two-year 3D gait outcomes in children with SCFE who have undergone in-situ pinning (PIN) or modified Dunn procedure (MDP) compared with normative reference values? Methods17 children with SCFE who had undergone PIN (n=7, slip severity mild to moderate) or MDP (n=10, slip severity moderate to severe) surgical procedures prospectively underwent a 3D gait analysis post-surgery (2∙0 ± 0∙5 years). Ten age-matched children were also recruited to provide normative reference values. The conventional gait model was modified to incorporate Hara hip equations and Lerner pelvic tracking methods. Gait Profile Scores, Gait Variable Scores, kinematics, kinetics and spatiotemporal data were calculated for each group. ResultsOverall gait pattern, determined by the Gait Profile Score, indicated that both SCFE groups differed from the normative reference group (PIN 6∙6 ± 2∙5⁰, MDP 6∙2 ± 2∙0⁰ vs. 4∙0 ± 1∙3⁰ norm, p<0∙05). Normalised walking speed was reduced in the MDP group (0∙40 ± 0∙04) compared to the normative reference group (0∙46 ± 0∙06; p=0∙032). SignificanceGait patterns of children with SCFE treated with PIN was more markedly altered than that of children with SCFE treated with MDP, despite having lower SCFE severity. Increased external hip rotation observed in the PIN group may be a pre-cursor for osteoarthritis in adulthood. Therefore the use of the corrective MDP which normalises hip rotation may be beneficial for reducing functional impairments.

Which jump test is most sensitive for classifying ACL injury history in fatigued or non-fatigued athletes?

Introduction &amp; Purpose In fast-paced clinical decision-making, jump-landing movement assessments are rarely used to guide return-to-sport (RTS) decisions after an anterior cruciate ligament (ACL) injury. While these tests are crucial for identifying deficits in movement execution (e.g., dynamic valgus, extended knee, knee internal rotation) that could predispose to ACL re-rupture (Kaplan &amp; Witvrouw, 2019), identifying these deficits can be challenging. To integrate RTS movement assessments into clinical practice, the first step is to identify the most sensitive jump-landing test that can best expose remaining deficits in neuromuscular control and resulting landing kinematics associated with ACL injury. Further, RTS tests are mostly performed in a non-fatigued state although fatigued individuals often fail to reach the RTS criteria (Dingenen &amp; Gokeler, 2017). This exploratory study aimed to rank common jump-landing tests in their ability to identify (sensitivity and classification rate) deficits in whole-body landing kinematics following ACL injury, under both fatigued and non-fatigued conditions. Methods A total of 43 volunteers were recruited into ACL group (n = 21, 11 females, 3.9 years post ACL injury) and control group (n = 22, 12 females). 3D motion data (Vicon, 250 Hz) were recorded during a single-leg forward hop (SH), single-leg countermovement jump (CMJ), single-leg triple crossover hop (COH), and single-leg 90° medial rotation hop (MRH) before and after a fatigue-inducing intervention (single-leg squats and step-ups). Thirteen joint angles (50 ms after initial contact) from the lower body, trunk, and pelvis representing the landing kinematics were calculated in OpenSim. A correlation analysis was performed to check for multicollinearity issues. Eight distinct logistic regression models (four jumps, fatigued/non-fatigued, α = .05) were computed to predict ACL injury history based on a combination of joint angles. For each model, a backward stepwise method was employed to determine which combination of joint angles resulted in the highest classification rates. Results ACL injury history was successfully predicted in seven (χ² &gt; 4.4, p &lt; .036) of the eight logistic regression models (Figure 1). The SH in the fatigued condition (χ² = 22.5, p = .008) demonstrated the highest sensitivity of 85.7% and a classification rate of 86%. Significant predictors for this model were knee rotation (Odds ratios [OR] = 1.537), hip abduction (OR = 1.385), hip rotation (OR = 1.525), and ankle flexion (OR = 0.771). The CMJ (non-fatigued) showed the second-highest sensitivity of 81% and a classification rate of 81.4% (p = .027). Significant predictors were knee rotation (OR = 1.440), hip abduction (OR = 1.428), hip rotation (OR = 1.297), and pelvis rotation (OR = 0.664). The MRH in the non-fatigued condition exhibited the lowest sensitivity, and no classification was possible in the non-fatigued COH model (χ² = 3.6, p = .056). Discussion &amp; Conclusion The fatigued SH was the most sensitive jump-landing test for classifying groups and detecting kinematic differences due to previous ACL injury. Thus, we recommended the SH over other tests for RTS decision-making, as it is most likely to reveal kinematic abnormalities. Higher classification rates in the fatigued condition support RTS testing in fatigued states to better identify movement deficits. To integrate jump-landing assessments into RTS decisions in a feasible way, our future work will involve 3D motion capture using pose estimation algorithms on video data.

Long-term computed tomographic osteolytic analysis of highly cross-linked polyethylene prosthesis after total hip arthroplasty

To analyze the occurrence of osteolysis in total hip arthroplasty (THA) with highly cross-linked polyethylene prosthesis during a follow-up of more than 15 years. The clinical data of 84 patients (105 hips) treated with THA in the Affiliated Hospital of Kanazawa Medical University in Japan between June 2000 and April 2004 and met the selection criteria was retrospectively analyzed. There were 7 males and 77 females, aged from 41 to 75 years, with an average of 56.4 years. There were 94 hips with secondary hip osteoarthritis, 4 hips after pelvic osteotomy, 2 hips with primary hip osteoarthritis, 2 hips with traumatic hip osteoarthritis, 2 hips with osteonecrosis of the femoral head, and 1 hip with rheumatoid arthritis. According to Crowe classification, there were 79 hips of type Ⅰ, 19 hips of type Ⅱ, 6 hips of type Ⅲ, and 1 hip of type Ⅳ. The highly cross-linked polyethylene acetabular liner combined with a 26 mm zirconia femoral head were used in all patients. X-ray films were taken after operation to analyze the radiation transmission and osteolysis around the acetabular prosthesis. The vertical distance (the distance between the teardrop line at the lower edge of the pelvis and the perpendicular line of the hip rotation center), the horizontal distance (the horizontal distance between the hip rotation center and the interteardrop line and the vertical line at the lower edge of the teardrop), and the acetabular cup anteversion angle were measured at last follow-up. The acetabular and femoral osteolysis was analyzed by CT scan and three-dimensional multiplanar reconstruction (3D-MPR). Combined with X-ray film and CT results, osteolysis was evaluated according to the Narkbunnam score. Deep vein thrombosis of lower limbs occurred in 2 cases. All patients were followed up 15-18 years, with an average of 15.9 years. One hip dislocation and 1 periprosthetic fracture occurred postoperatively, and no acetabular loosening or prosthetic lining ruptures occurred. Except for 1 patient who had a radiolucent line in the acetabulum after operation, the other 83 patients did not show any radiolucent line in the acetabulum or the femur. None of the patients underwent hip revision. X-ray films at last follow-up showed an acetabular cup anteversion angle of -10°-39°, with an average of 22°; a vertical distance of 3.5-47.1 mm, with an average of 24.6 mm; and a horizontal distance of 22.6-48.1 mm, with an average of 31.7 mm. There was no acetabular or femoral osteolysis in all patients on X-ray films and CT 3D-MPR images at last follow-up, and the Narkbunnam score was 0 in any region. Highly cross-linked polyethylene prosthesis does not increase the risk of long-term complications such as osteolysis after THA.

Hip Range of Motion and Strength in Young Pre-Professionals Ballet Dancers Versus Non-Dancers.

Introduction: Lower-extremity external rotation, commonly known as turnout, is a fundamental skill in dance. Limited data exist regarding joint range of motion and strength in pre-professional young dancers and non-dancers. This study aimed to evaluate the differences in hip range of motion and hip strength between pre-professional ballet dancers and non-dancers. Additionally, the study assessed the variations between the left and right sides within each group. Methods: This observational study assessed 60 pre-professional ballet dancers and 31 non-dancers with an average age of 11.91 ± 1.49. Evaluation included passive hip rotation, tibial torsion, total passive turnout measured with digital goniometers, and total active turnout (both static and dynamic) through standing on paper and rotational discs. Hip rotation strength was measured using a force sensor device. Statistical analyses encompassed student t-tests, Pearson's correlations, and ANCOVA with age and body weight as covariates, applying the Bonferroni correction for multiple comparisons. Results: Ballet dancers exhibited greater passive hip external rotation and lower passive hip internal rotation compared to non-dancers. They also demonstrated superior total active turnout (static and dynamic). After adjusting for age and weight, dancers demonstrated significantly higher hip external rotation strength than non-dancers. Hip internal rotation strength did not differ significantly between the groups. Ballet dancers displayed inherent asymmetry, with the left side showing greater tibial torsion and standing active turnout, while the right side exhibited greater hip external rotation during dynamic active turnout. Non-dancers did not show significant side differences. Conclusions: Young pre-professional ballet dancers exhibited significant hip rotation differences compared to non-dancers, including notable right-left asymmetry. These findings should be considered when planning training, aiming to optimize musculoskeletal attributes and promote balanced hip rotation. Recognizing these asymmetries and addressing muscular imbalances is vital for injury prevention and performance enhancement.

One-stage revision for reconstructing acetabular defects by trabecular metal acetabular revision system in periprosthetic joint infection

Objective: To investigates the clinical efficacy of the trabecular metal acetabular revision system (TMARS) in one-stage reconstruction of acetabular deficiencies associated with periprosthetic joint infection (PJI). Methods: This is a retrospective case series study,including the data of 59 patients with PJI underwent acetabular defect reconstruction by TMARS during one-stage revisions in the Department of Orthopaedics, the First Affiliated Hospital of Xinjiang Medical University from January 2013 to December 2021. There were 32 males and 27 females, aged (59.5±14.6) years (range: 26 to 84 years). Among them, 29 cases used tantalum cups, 13 cases used tantalum cups and tantalum reinforcing blocks, 9 cases used cup-cage, and 8 cases used multi-cup reconstruction techniques. The surgery procedure, Harris Hip score (HHS), recovery of the hip rotation center, implant survival rate, postoperative reinfection rate, and complications were recorded. Data were compared using the Wilcoxon rank-sum test. Results: All of the 59 patients underwent the operations successfully. Operation time was (188.9±48.4) minutes (range: 110 to 340 minutes), and intraoperative bleeding volume was (M(IQR)) 1 000(400)ml (range: 600 to 1 800 ml). After a postoperative follow-up of 5.1 (2.6) years (range: 2.0 to 10.5 years), the prosthesis survival rate was 94.9% (56/59). Recurrence of infection occurred in 3 cases (5.1%), aseptic loosening in 1case(1.7%), and hip dislocation in 4 cases (6.8%). At the last follow-up, HHS improved significantly(84 (12) vs. 44 (9), Z=-6.671, P<0.01), and the center of rotation of the hips were recovered in all cases. Conclusions: In one-stage revision surgeries aimed at reconstructing acetabular defects, utilizing the TMARS can provide stable initial fixation, restore a more natural center of rotation, significantly enhance early postoperative hip joint function, and reduce the likelihood of infection recurrence. This approach stands as a reliable choice for addressing acetabular defects during revision surgeries for infected hip joints.

Femoroacetabular impingement syndrome in middle-aged individuals is strongly associated with the development of hip osteoarthritis within 10-year follow-up: a prospective cohort study (CHECK)

ObjectiveThe objective is to determine the association and absolute risk of femoroacetabular impingement syndrome (FAIS) for the development of radiographic hip osteoarthritis (RHOA).MethodsThis is a nationwide, multicentre prospective cohort study...

Establishing a Reference Database for Select Clinical Measures in National Basketball Association Players.

Musculoskeletal injuries are prevalent in the NBA and are associated with a significant number of games missed. There is a lack of reference data for clinical measures in NBA players, making it difficult for sports medicine professionals to set goals and develop programs. Values for clinical measures in NBA players will differ from those of the general population but will not differ between dominant (D) and nondominant (ND) limbs. Descriptive laboratory study. Level 3. Clinical measures were taken on 325 players invited to NBA training camp (2008-2022). Measures included range of motion for great toe extension, hip rotation, weightbearing ankle dorsiflexion, flexibility, arch height (AH) indices, and tibial varum. Clinical values for NBA players differ from reference norms of the general population. Results for NBA players include great toe extension (D, 40.4°; ND, 39.3°), 90/90 hamstring (D, 41.5°; ND, 40.9°), hip internal rotation (D, 29.0°; ND, 28.8°), hip external rotation (D, 29.7°; ND, 30.9°), total hip rotation (D, 60.2°; ND, 60.4°), Ely (D, 109.9°; ND, 108.8°), AH difference (D, 0.5 mm; ND, 0.5 mm), AH index (D, 0.310; ND, 0.307), arch stiffness (D, 0.024; ND, 0.024), arch rigidity (D, 0.924; ND, 0.925), tibial varum (D, 4.6°; ND, 4.5°), and weightbearing ankle dorsiflexion (D, 35.4°; ND, 35.6°). Descriptive statistics are presented; 2-tailed paired t tests show that, whereas most measures demonstrated differences between sides, the results were not statistically significant. Clinical measures of NBA players differ from those reported for the general population and athletes of other sports although there were no statistically significant differences between D and ND limbs. Establishing a reference database may help clinicians develop more sensitive and more effective preseason and return-to-play screening processes, aiding the management of player orthopaedic care and reducing injury risk.

Immediate effect of posture-dependent and weight-bearing gluteus medius exercise on muscle function in the lower extremities and dynamic knee valgus

BACKGROUND: The gluteus medius (GM) plays an important role in stabilizing the knee and preventing injury. OBJECTIVE: This study aimed to determine the immediate effects of weight-bearing gluteus medius exercises on lower-extremity muscle function and dynamic knee valgus. METHODS: Eighteen healthy adults (nine each of both sexes) performed three types of weight-bearing gluteus medius exercises (standing, mini-squat, and dead-lift), and a range of kinematic variables were tested in triplicate. Weight-supporting GM exercise consisted of three sets of 15 repetitions of the lateral band walk. The Y-balance test (YBT) and vertical single-leg jump were used as indicators of muscle function in the lower limbs. We used a video analyzer to film the dynamic knee valgus and performed a YBT for the supporting leg and landing leg following a jump. RESULTS: The height of the single-leg vertical jump and the posterolateral and total YBT scores were significantly higher in the dead-lift posture than in the standing and mini-squat postures. Motion analysis of the dead-lifts revealed high hip flexion on the supporting leg in the posterolateral direction, as determined by the YBT, with low levels of internal hip rotation on the landing leg during the one-leg vertical jump. CONCLUSION: As an immediate effect of gluteus medius exercise, the dead-lift posture facilitated single-leg vertical jump, posterolateral balance, and reduced dynamic knee valgus.

A Comparison of Combined Pilates-Kinesio Tape and Mulligan-Kinesio Tape Exercises on Pain, Lumbar Range of Motion, Hamstring Strength, and Pelvic Rotation in Women with Non-specific Chronic Low Back Pain

Background: Low back pain is one of the most significant musculoskeletal problems, causing various functional limitations that adversely affect individuals' quality of life. Objectives: The effect of combined Pilates-Kinsey and Mulligan-Kinsey exercises in women with non-specific chronic back pain has not been investigated. Methods: In the present quasi-experimental study, thirty women with non-specific chronic back pain with a range age of 35 - 65 years old were included in the study and were randomly divided into two Pilates-Kinesiotype (n = 15) and Mulligan-Kinesiotype (n = 15) groups. Exercise interventions were conducted for 6 weeks and 3 sessions per week. Pain, lumbar range of motion, hamstring stiffness and hip rotation were measured before and after the training intervention. Also, analysis of covariance (ANCOVA) test was used to analyze the data. Results: The results showed that there is a significant difference between the effect of Pilates-Kinesiotype training and Mulligan Kinesiotype training in the variables of pain, hamstring stiffness and hip rotation (P &lt; 0.05) and the reduction of pain and hip rotation in the Pilates-Kinesiotype training group compared to The Mulligan-Kinesiotype group was better. But the hamstring range of motion was better in the Mulligan-Kinesiotype group than in the Pilates-Kinesiotype group. In addition, the results showed that there is no significant difference between the waist range of motion of the research groups (P &lt; 0.05). Conclusions: Due to the fact that mulligan and Pilate's exercises together with Kinesiotype have an effect on pain variables, hamstring stiffness and hip rotation, and each of mulligan and Pilate's exercises have different effectiveness. These exercises can be used in combination with Kinesiotype to help women with non-specific chronic back pain.

Effect of femoral derotational osteotomy in patients with idiopathic increased femoral anteversion on joint loading and muscular demands.

This study aimed to analyse the effect of the femoral derotational osteotomy (FDRO) on joint kinematics, kinetics, joint and muscle forces, and muscle moments in patients with idiopathic increased femoral anteversion compared with typically developing children (TDC). In this retrospective study, 17 patients (25 limbs, 13.2 ± 2.2 years, femoral anteversion = 49.0° ± 7.1°) were compared to nine TDC (9 limbs, 12.0 ± 3.0 years, femoral anteversion = 18.7° ± 4.1°). Gait analysis was performed 8.5 ± 7.2 months pre-surgery and 17.3 ± 5.5 months post-surgery. Joint angles, moments and forces as well as muscle forces and muscle contributions to joint moments were analysed using statistical parametric mapping. Significant improvements in kinematics (hip rotation, foot progression, knee and hip flexion) were observed pre- to post-FDRO. Joint forces remained unaltered after surgery and did not differ from TDC. Gluteus minimus and deep external rotators muscle forces decreased in mid-stance, while adductor muscle forces increased during stance post-op compared to pre-op. Due to an improved knee extension postoperatively, the rectus femoris muscle force decreased to normal values during mid- and terminal stance. Postoperatively, only the deep external rotator muscle forces differed from TDC. This study showed that FDRO can restore muscle forces and muscle contributions to joint moments in addition to normal gait kinematics, while joint contact forces remain within normative ranges. This knowledge might also apply to other conditions in which pathological femoral anteversion is present.

Pelvic limb monoparesis with excessive external hip rotation in a dog.

Pelvic limb monoparesis with excessive external hip rotation in a dog.

Borderline Developmental Dysplasia of the Hip With Osseous Impingement as Distinct From Femoroacetabular Impingement and Developmental Dysplasia of the Hip.

Borderline developmental dysplasia of the hip (BDDH) accompanied by cam deformity and subspinous impingement has been found to benefit from arthroscopic surgery. However, the research comparing BDDH combined with osseous impingement to femoroacetabular impingement (FAI) without borderline dysplasia remains limited. To compare the clinical symptoms, intraoperative findings, and outcomes of hip arthroscopy in patients with BDDH and osseous impingement versus cam-type FAI. It was hypothesized that BDDH with osseous impingement could be classified as a distinct entity between FAI and developmental dysplasia of the hip (DDH). Cohort study; Level of evidence, 3. Data were collected from patients 18 to 50 years old who underwent primary hip arthroscopy between September 2016 and October 2020. Patients were divided based on preoperative lateral center-edge angle (LCEA) into 2 groups: (1) BDDH group (LCEA 18°-25°; n = 67); and (2) cam-type FAI group without BDDH (FAI group; LCEA 25°-40° and alpha angle >55°; n = 145). Disparities in symptoms, preoperative examination, intraoperative findings and procedures, and patient-reported outcome (PRO) scores were compared. Follow-up was available for 61 (91.0%) patients in the BDDH group and 125 (86.2%) patients in the FAI group. The incidence of cam deformity in BDDH patients was 91.8%. The preoperative characteristics and intraoperative findings were similar between the groups; however, preoperative internal and external hip rotation, Tönnis angle, femoroepiphyseal acetabular roof index, labral size, capsule thickness, and percentage of ligamentum teres tear were significantly higher in the BDDH group than the FAI group, and the percentage of pain aggravating factor, cam deformity, and anterior inferior iliac spine types 2 and 3 were also significantly different between groups (P < .05 for all). The percentage of intraoperative minimal acetabuloplasty, subspinous decompression, labral repair, ligamentum teres debridement, and capsular closure was significantly higher in the BDDH group than the FAI group, while the percentage of femoroplasty was higher in the FAI group (P < .05). Pre- to postoperative improvement on PRO scores was seen in both groups. Given the differences in etiology and surgical procedures between the 2 conditions, it is suggested that BDDH with osseous impingement be classified as an entity distinct from FAI and DDH (and separate from BDDH without impingement) while excluding joint instability.

Is There a Pathologic Running Motion Associated with Running-Related Injuries? A Methodological Study Using a Motion Analysis System Without Sensors.

(1) Background and objectives: Running-related injuries (RRIs) are commonly attributed to improper running posture and overuse. This study aims to analyze the running motions of individuals with and without RRIs using a sensor-free method, which offers a user-friendly and straightforward approach. (2) Materials and Methods: A total of 155 runners were divided into two groups: the normal runner group (runners who had never been injured, n = 50) and the RRI group (runners who had experience at least one injury while running, n = 105). The forward head posture (FHP), trunk lean, hip rotation, horizontal movement of the center of gravity (COG), vertical movement of the COG, pelvic rotation, hip hike, and type of strike were measured for posture analysis. (3) Results: We found that the left-right balance of the pelvis and the spinal posture during running were associated with RRIs. The difference in hip hike and FHP emerged as key predictors of running-related musculoskeletal injury occurrence from our logistic regression analysis. (4) Conclusions: Identifying pathological movements in runners through running motion analysis without the use of sensors can be instrumental in the prevention and treatment of RRIs.

Impacts of asymmetric hip rotation angle on gait biomechanics in patients with knee osteoarthritis

BackgroundKnee Osteoarthritis (OA) is a highly prevalent age-related disease. The altered kinematic pattern of the knee joint as well as the adjacent joints affects to progression of knee OA. However, there is a lack of research on how asymmetry of the hip rotation angle affects the gait pattern in knee OA patients.Research questionWhat are the impacts of asymmetric hip rotation range on gait biomechanical characteristics and do the gait patterns differ between patients with knee OA and healthy elderly people?MethodsTwenty-nine female patients with knee OA and 15 healthy female elders as control group were enrolled in this study. The spatiotemporal parameters, kinematic and kinetic data during walking were measured using a three-dimensional motion capture system. The differences between knee OA and control group were analyzed using an independent t-test.ResultsThe knee OA group exhibited a significant reduction in hip internal rotation range and internal/external rotation ratio on more affected side (p < 0.05). Significant differences were found in spatiotemporal parameters except to the step width. Significant reductions were also found in kinematic parameters (pelvic lateral tilt range, sagittal angle ranges in hip, knee and ankle, knee adduction mean angle). There were also significant differences in vertical ground reaction force and knee adduction moment (p < 0.05).ConclusionsKnee OA patients have asymmetric hip rotation ranges. Especially limited hip internal rotation could lead to the reduction of pelvic lateral tilt, which may cause greater knee joint loading. Therefore, it is necessary to pay attention to recovery of hip rotation after knee surgery.