Hip Internal Rotation Research Articles

Two-to-three times increase in natural hip and lumbar non-sagittal plane kinematics can lead to anterior cruciate ligament injury and cartilage failure scenarios during single-leg landings

BackgroundAnalyzing sports injuries is essential to mitigate risk for injury, but inherently challenging using in vivo approaches. Computational modeling is a powerful engineering tool used to access biomechanical information on tissue failure that cannot be obtained otherwise using traditional motion capture techniques. MethodsWe extrapolated high-risk kinematics associated with ACL strain and cartilage load and stress from a previous motion analysis of 14 uninjured participants. Computational simulations were used to induce ACL failure strain and cartilage failure load, stress, and contact pressure in two age- and BMI-matched participants, one of each biological sex, during single-leg cross drop and single-leg drop tasks. The high-risk kinematics were exaggerated in 20% intervals, within their physiological range of motion, to determine if injury occurred in the models. Where injury occurred, we reported the kinematic profiles that led to tissue failure. FindingsOur findings revealed ACL strains up to 9.99%, consistent with reported failure values in existing literature. Cartilage failure was observed in all eight analyzed conditions when increasing each high-risk kinematic parameter by 2.61 ± 0.67 times the participants' natural landing values. The kinematics associated with tissue failure included peak hip internal rotation of 22.48 ± 19.04°, peak hip abduction of 22.51 ± 9.09°, and peak lumbar rotation away from the stance limb of 11.56 ± 9.78°. InterpretationOur results support the ability of previously reported high-risk kinematics in the literature to induce injury and add to the literature by reporting extreme motion limits leading to injurious cases. Therefore, training programs able to modify these motions during single-leg landings may reduce the risk of ACL injury and cartilage trauma.

Handheld dynamometry: Validity and reliability of measuring hip joint rate of torque development and peak torque.

Measuring rate of torque development (RTD) and peak torque (PT) for hip muscle performance presents challenges in clinical practice. This study investigated the construct validity of a handheld dynamometer (HHD) versus an isokinetic dynamometer (IKD), and intra-rater repeated reliability for RTD and PT and their relationship in hip joint movements. Thirty healthy individuals (mean age = 30 ± 8 years, 13 males) underwent two test sessions in a single day. RTD (0-50, 0-100, 0-150, 0-200ms) and PT normalised to body mass in maximal voluntary isometric contractions were measured using a HHD and an IKD in hip flexion, extension, abduction, adduction, internal and external rotation. For validity between the devices, RTD0-50 exhibited the largest significant systematic bias in all hip movements (3.41-11.99 Nm·s-1 kg-1) and widest limits-of-agreement, while RTD0-200 had the lowest bias (-1.33-3.99 Nm·s-1 kg-1) and narrowest limits-of-agreement. For PT, agreement between dynamometers was observed for hip flexion (0.08 Nm·kg-1), abduction (-0.09 Nm·kg-1), internal (-0.01 Nm·kg-1), and external rotation (0.05 Nm·kg-1). For reliability, intra-rater intraclass correlation coefficient (ICC2,1) ranged from moderate to good in RTD0-50 and RTD0-100 (0.5-0.88), and good to excellent in RTD0-150 and RTD0-200 (0.87-0.95) in all movements. The HHD displayed excellent intra-rater, relative reliability values (ICC2,1) in all movements (0.85-0.95). Pearson's correlation revealed good linear correlation between PT and RTD0-150 and RTD0-200 in all movements (r = .7 to .87, p = < .001). Validity analysis demonstrated significant systematic bias and lack of agreement in RTD measures between the HHD and IKD. However, the HHD displays excellent to moderate intra-rater, relative reliability for RTD and PT measures in hip movements. Clinicians may use the HHD for hip muscle PT assessment but note, late phase RTD measures are more reliable, valid, and relate to PT than early phase RTD. Additionally, the correlation between RTD and PT at various time epochs was examined to better understand the relationship between these measures.

Factors Informing Training Load During the Transition From Club to National Football Teams.

This study examined the relationship of precamp match exposure, travel demands, perceptual wellness, and musculoskeletal screening with ensuing training load (TL) during national-team (NT) duties for international footballers (soccer). Match minutes and days since last match prior to NT arrival were collected for match exposure. Travel duration and time-zone difference were included as travel demands. Perceptual fatigue, soreness, sleep quality, and stress scores were collected via self-report questionnaire on arrival to NT. Musculoskeletal testing on day 1 of NT included knee to wall and hip internal and external rotation. Relative TL across the first 3 days of NT camp was measured via total distance, high-speed runningdistance, very high-speed running distance, and accelerations and decelerations per minute. Linear mixed models determined the influence of independent variables on respective TL metrics, with the player included as a random effect. Total distance, high-speed running, very high-speed running, and decelerations per minute were all highest on day 3 (P < .001). Small relationships existed (R2 < .15) between decreased total distance per minute and increased soreness (P = .037), while decreased high-speed running per minute was associated with increased fatigue (P = .017). Small associations existed between decreased accelerations per minute, increased hip internal rotation(P < .001), fatigue (P = .033), and knee to wall (P = .016), while decreased decelerations per minute were associated with increased soreness (P = .001), knee to wall (P = .024), and days between recent match and arrival (P = .003). Very small relationships existed between fatigue, soreness, musculoskeletal screening, and prior match exposure with TL. The larger influence of camp day suggests that deliberate periodization of training is a major factor for prescription on arrival into NT duties.

The Biomechanical and Functional Status of Patients with Knee Osteoarthritis - A Cross Sectional Study

Background and Objectives: Knee deformity associated with osteoarthritis (OA) is one of the most common complications reported to orthopaedic surgeons. Genu valgum and genu varum are the most commonly occurring deformities due to knee osteoarthritis. When there is progression in degeneration due to osteoarthritis, deformities tend to worsen and will eventually lead to reduction in cadence rate, hindfoot angle, range of motion in both hip and knee. Thus, this study is conducted to analyze these parameters like cadence, hindfoot angle, hip internal flexion, knee flexion, WOMAC scale and VAS pain rating scale between the groups of individuals with Genu valgum and genu varum deformity. Methodology: A convenient division was made of a total of 80 knee osteoarthritis (OA) patients into two groups by measuring their medial tibiofemoral angle, namely Genu valgum and genu varum. The patients were evaluated for various parameters including gait cadence, reduced knee flexion, hip internal rotation, hind foot angle, WOMAC scale, and VAS pain scale. The discrepancies in these parameters were analyzed between the Genu valgum and genu varum groups. This study design represents a cross-sectional approach. Results: The Independent t-test was used to examine the results among the groups, with a significance level set at p ≤ 0.05. Considerable statistical changes were observed in cadence, hindfoot angle, knee flexion ROM, and hip internal rotation ROM, with corresponding p-values of 0.0006, 0.049, 0.002, and 0.01, respectively. However, no significant differences were found in the case of the WOMAC scale and VAS pain rating scale between the groups with Genu valgum and genu varum deformities, as their p-values were considerably higher than the significance level (0.169, 0.948). Conclusion: The objective of the study was to gain insight into the biomechanical and functional condition of individuals suffering from knee osteoarthritis. Substantial differences were observed between the groups regarding cadence, hindfoot angle, knee flexion range of motion (ROM), and hip internal rotation ROM. However, when evaluating the WOMAC scale and VAS pain rating scale, both groups exhibited nearly identical values, indicating a lack of statistical significance in these outcome measures.

Sex differences in factors of pelvis and lower-limb joint kinematics influencing dynamic knee valgus during single-leg squat.

Dynamic knee valgus (DKV) during dynamic activity is associated with patellofemoral pain, one of the most common sports disorders, especially in females. No studies have examined the factors that can lead to DKV in females as compared to males while addressing the influence of factors on each other. To identify factors of pelvis and lower joints kinematics affecting DKV during single-leg squat (SLS) in females compared to males with multiple regression analysis. Forty-four healthy young people (24 females, 20 males) performed SLS, and pelvis, hip, knee, and ankle 3D kinematics were recorded. The 2D knee frontal plane projection angle (FPPA) was adopted as the DKV measurement. Multiple regression analysis was performed to determine the relationship between FPPA and the kinematics of each joint and segment. Hip adduction and pelvic contralateral rotation were explanatory factors for FPPA in females. Hip adduction, hip internal rotation, and knee external rotation were explanatory factors in males. The lower limb or pelvic motion factors affecting DKV during SLS differ between the sexes, with pelvic contralateral rotation being extracted only in women, possibly due to differences in pelvic width.

INVESTIGAÇÃO QUANTITATIVA E QUALITATIVA DA ANÁLISE TRIDIMENSIONAL DA MARCHA EM PACIENTES COM MIELOPATIA CERVICAL

ABSTRACT Objective: This study aims to describe a kinematic gait assessment protocol and identify its main alterations in individuals with cervical spondylotic myelopathy (CSM) compared to healthy patients. Methods: In total, 14 patients diagnosed with CSM were enrolled and submitted to a three-dimensional gait analysis. The movement of patients was captured with infrared emission cameras that identified tracking markers placed on the lower limbs. Reference positions were used, and the patients walked along a rubberized walkway. The Gait Profile Score (GPS) and Movement Analysis Profile (MAP) were used to analyze variables. Results were subjected to a Student’s t-test at 95% confidence interval. The R Core Team (2016) software was used for statistical analysis, graphically comparing the study results with data from healthy patients. Results: When comparing the kinematic data bilaterally, no statistical differences were found. However, graphical analysis showed changes in the gait of patients with CSM compared to healthy individuals. There were differences in all movements, with a more significant discrepancy in hip and knee flexion and extension, dorsiflexion and plantar flexion, and internal and external hip rotation. Conclusion: We describe a protocol for gait kinematics assessment using GPS and MAP, and we presented the differences in gait kinematics in patients with CSM compared to healthy individuals. Level of Evidence II, Prospective study.

Association between lower limb alignment and low back pain: A systematic review with meta-analysis.

Low back pain (LBP) is a prevalent and costly condition globally, prompting the need to identify risk factors for effective management. Lower extremity misalignment plays a crucial role in the incidence of LBP. Therefore, we aimed to investigate the current evidence on a link between lower limb alignment and LBP, enhancing the understanding of this relationship. We searched four databases, including PubMed, Embase, Web of Science, and Scopus, up to September 2024. Inclusion criteria encompassed studies related to LBP and lower limb alignment, with eligible study types including case-control, cohort, and cross-sectional studies, all written in English. Two authors independently screened and assessed the methodological quality of the retrieved papers using the Downs and Black quality assessment checklist. Data of interest including study design, age, sample size, cases, association, and P-value were extracted from the included studies. Mean differences and 95% confidence intervals (CI) were calculated with random effects model in RevMan version 5.4. Thirteen articles evaluating lower limb alignment in individuals with LBP were included (102,359 participants in total). The meta-analysis results demonstrated that increased pronation with strong evidence(p = 0.02), increased hip internal rotation with moderate evidence, and increased knee internal rotation with limited evidence are associated with an increased risk of LBP. Overall, while some studies supported a relationship between lower limb alignment and LBP, the heterogeneity of study designs and methodological limitations hindered drawing a definitive conclusion. Future research should emphasize prospective cohort studies, incorporating objective measures of lower extremity alignment and standardized outcome measures.

Lumbar Spondylolysis in Ambulant Children with Spastic Cerebral Palsy.

Lumbar spondylolysis is a common condition; nonetheless, its cause in patients with spastic cerebral palsy (CP) remains unknown. Furthermore, examination of children with CP may not accurately capture complaints, thus causing diseases to be overlooked. Understanding the clinical features and gait patterns of lumbar spondylolysis in CP can aid in diagnosis. This study aimed to identify the clinical features and specific gait patterns of lumbar spondylolysis in ambulatory children with CP. Seventy-three children with CP were divided into two groups according to the presence or absence of lumbar spondylolysis on X-ray and magnetic resonance imaging. Three-dimensional gait analysis (3DGA) was performed to evaluate the kinematic data of the lower limbs. Eight participants (11.4%) had lumbar spondylolysis primarily affecting the L5 vertebra. The lumbar spondylolysis group had a higher body weight and Body Mass Index, along with a smaller left popliteal angle on the spastic side. In 3DGA, detailed kinematic data indicated significant group differences in the mean angles of hip internal rotation (39.6° vs. 20.2°) during an entire gait cycle. The gait profile score was 19.7° in the lumbar spondylolysis group and 14.9° in the spinal uninvolved group; the difference in gait profile score between the two groups showed a minimal clinically important difference of 2.75. The overall gait profile score revealed that the gait of the lumbar spondylolysis group was deteriorated. Excessive internal rotation of the hip during gait might be a contributing factor to lumbar spondylolysis in children with CP.

Relation Y-Balance Test and Lower-limb Strength of Sport Science Faculty Students at the Arab American University

The purpose of this study was to elucidate the relationship between the Y-balance test (YBT) distance and the lower-limb strength of Sport Science Faculty students at Arab American University. Forty (40) collegiate students aged (19.80 ± 1.26) years, enrolled in the second semester of the 2022-2023 academic year from the sports science department, volunteered for this study. The participants underwent MMT (Manual Muscle Testing) to evaluate the maximum muscle strength of the lower limbs, including hip flexion, hip extension, hip abduction, hip adduction, hip internal rotation, hip external rotation, knee flexion, knee extension, ankle dorsiflexion, and ankle plantar flexion). Additionally, they performed the Y-Balance Test (YBT) evaluations in the anterior, posteromedial, and posterolateral directions. An independent sample t-test was used to compare the means between two groups, specifically males and females, to assess the differences. Pearson's correlation coefficient was used to quantify the linear relationships between YBT distances and lower-limb strength. The hip extension was positively correlated with the YBT distances in the anterior, posteromedial, and posterolateral distances. Furthermore, hip flexion and hip abduction were positively correlated with the anterior and posteromedial YBT distances. Knee flexion and knee extension strength showed a positive correlation with the YBT anterior distance. In conclusion, there was a weak correlation between lower-limb strength (hip flexion, hip extension, hip abduction, knee flexion, and knee extension) and dynamic postural control, as measured by the YBT, and this achieves one of the sustainable development goals of the United Nations in Iraq which is (Good Health).

Could dry needling change the kinematics of gait in individuals with piriformis muscle syndromes? Secondary analysis of a randomized controlled trial

IntroductionPiriformis muscle syndrome (PMS) is a condition that can lead to symptoms including gluteal pain, local tenderness, and limitation of hip joint motion in daily activities, and it may have a major impact on some daily functions such as gait. We proposed that dry needling (DN) can improve the gait of individuals with PMS. MethodsThirty-two individuals with PMS were assigned equally and randomly to the treatment group or the wait-list control group. Subjects in the treatment group received three sessions of DN of the piriformis muscle. All participants in both groups were educated to correct their lifestyles. The outcome measures were the gait-related parameters (walking speed, peak hip flexion, peak hip extension, time to peak internal and external hip rotation, and knee sagittal range of motion), which were evaluated at baseline and after treatment. To compare different outcomes, analysis of covariance (ANCOVA) was used, with baseline as the covariance and groups as a factor. ResultAfter DN sessions, peak hip extension during gait showed a statistically significant difference [adjusted MD 1.9 (3.7–0.08), p < 0.05, d = 0.56 (0.1–1.28)] in favor of the DN group. Peak hip flexion, on the other hand, exhibited a marginal statistically significant difference [adjusted MD -3.2 (−6.51 to 0.01), p = 0.053, d = 0.44 (1.16 to −0.02)] compared to the control group. ConclusionThe findings suggest that participants in DN showed significantly greater peak extension angle of the hip during walking in individuals with PMS than in the control group.

L’efficacité des semelles posturales dans la gestion de la posture chez les personnes atteintes de paralysie cérébrale : une revue de portée

BackgroundChildren with cerebral palsy often have gait abnormalities that can affect their daily activities. Insoles have been used as a treatment option to improve walking in children with cerebral palsy, but their efficacy remains uncertain. The aim of this study was to investigate the effects of postural insoles with corrective elements on gait parameters in children with cerebral palsy. MethodsChildren with cerebral palsy often have gait abnormalities that can affect their daily activities. Insoles have been used as a treatment option to improve walking in children with cerebral palsy, but their efficacy remains uncertain. The aim of this study was to investigate the effects of postural insoles with corrective elements on gait parameters in children with cerebral palsy. ResultsOf 35 initial registrations, three studies met the inclusion criteria. Results showed that postural insoles are effective in improving foot biomechanics and posture. However, the quality of the evidence was generally low, and further high-quality studies are needed to confirm these results. ConclusionsPostural insoles with corrective elements may be an effective treatment option for improving gait parameters in children with cerebral palsy. The use of these semelles can lead to an increase in cadence and speed, as well as an improvement in the range of motion of ankle dorsiflexion and a decrease in the range of motion of knee flexion and hip internal rotation.

The Association among Physical Activity, Sociodemographic, Trunk Muscles Thickness and Low Back Pain-Related Disability in Amateur Soccer Players: An Observational Study

Abstract Objective Although low back pain (LBP) is one of the most common musculoskeletal disorders, there is limited evidence assessing which factors contribute LBP severity in amateur athletes. We aimed to analyze relationships between sociodemographic, clinical, lifestyle and lumbar multifidus (LM) at L4 and L5 levels, rectus abdominis (RA), external and internal obliques (EO and IO) and transversus abdominis (TrA) muscles thickness assessed with ultrasound imaging (US) variables with lumbar disability in amateur athletes with LBP and lumbar disc herniation. Methods Eighty-two male amateur soccer athletes were analyzed. Demographic data, internal hip rotation, finger-floor distance, pain intensity, number of LBP episodes within the last year, metabolic equivalent of tasks for physical activity, sitting time, muscle thickness and disability caused by LBP were collected. Results Pain intensity showed significant associations with LBP recurrence, disability, sedentarism, trunk and hip flexibility, vigorous physical activity and TrA, EO and RA muscles thickness (p&lt;0.05). Similarly, disability was associated with number of LBP episodes, vigorous activity, sitting time, finger floor distance, and RA, EO and IO muscles thickness (p&lt;0.05). TrA thickness and internal hip rotation were not associated with lumbar disability (p&gt;0.05). Conclusion LBP intensity and pain-related disability were significantly associated with LBP episodes, vigorous activity, sitting time, finger floor distance, and thickness of abdominal muscles were associated with pain intensity and disability. However, lumbar multifidus thickness at rest, ankle dorsiflexion and walking time were not associated with clinical severity.

Effect of Hip Mobilization with Movement in Weight-Bearing Position on Mobility of Hip Internal Rotation

Effect of Hip Mobilization with Movement in Weight-Bearing Position on Mobility of Hip Internal Rotation

Lower extremity characteristics and postural alignment in young pre-professional dancers

ABSTRACT Lower extremities (LE) play a fundamental role in ballet technique, yet they are not often assessed as thoroughly as other areas of the body in the youngest pre-professional dancers. The aim of this study was to assess the functional and structural characteristics in the LE of first-grade dance conservatory students to a more thorough extent. This study included a manual assessment of LE length in supine and sitting positions, measuring passive hip internal rotation (PHIR) and external rotation (PHER), comparing PHIR/PHER between both sides, functional assessment and visual inspection of rear and forefoot, classification of joint mobility, and inspection of postural alignment. Seventy-eight young dance students (9.5 ± 2.5 years, 91% female) were evaluated. Over 60% presented LE length discrepancy in both supine and sitting positions. Asymmetry of PHIR and PHER was detected. Signs of increased pronation were observed in 62.8% of cases, and 24.4% presented indications of postural asymmetry and/or scoliosis. Including the tests performed in this study in dance screenings may help in detecting functional characteristics of LE earlier. These in turn might affect the performance of young students; but if detected early, they can be assisted with correction or treatment.

The McMaster osteotomy-a novel surgical treatment to chronic slipped capital femoral epiphysis: description ofsurgical technique andcase study.

Slipped capital femoral epiphysis (SCFE) is a common adolescent hip disorder that can lead to complex proximal femur deformities and devastating consequences such as avascular necrosis, femoroacetabular impingement syndrome and early-onset osteoarthritis. Existing surgical techniques are often insufficient to fully address the constellation of multiplanar deformities in patients with severe SCFE. Therefore, the McMaster Osteotomy, a novel intertrochanteric proximal femur osteotomy, was developed to improve anatomic correction and hip mechanics in patients with chronic SCFE. The McMaster Osteotomy was implemented in two patients (A: 16-year-old male, B: 17-year-old female) with proximal femur deformities due to chronic SCFE. Surgical planning was facilitated with a 3D-printed pelvic model generated from a CT scan of a patient with the SCFE deformity. Patient B also underwent concurrent arthroscopic osteochondroplasty and labral repair. Pre- and post-operative function and radiographic measurements were recorded. Post-operatively, patient A's neck-shaft angle improved from 125° to 136°, Southwick angle from 52° to 33°, neck length from 66 mm to 80 mm and hip internal rotation from 5° to 25°. Patient B's post-operative neck-shaft angle improved from 122° to 136°, Southwick angle from 25° to 15°, neck length from 76 mm to 84 mm, hip internal rotation from 5° to 20° and alpha angle from 87.6° to 44.3°. Both patients are pain-free and have obtained full union of their osteotomies. The McMaster Osteotomy is a versatile technique that can produce a more anatomic reconstruction of hip anatomy and restoration of abductor mechanics. As an extracapsular technique, the risk of femoral head avascular necrosis is minimized.

Total Hip Arthroplasty for Low-Grade Developmental Hip Dysplasia Changes the Ipsilateral Knee Alignment on the Axial and Coronal Planes

Background: There is a paucity of data regarding the post-operative influence of total hip arthroplasty (THA) on the axial and coronal alignments of the ipsilateral knee. A CT study was designed to assess the post-THA changes in axial and coronal knee alignments in low-grade dysplastic hips. Methods: Forty Crowe I–II dysplastic hips in 37 patients were assessed: a pre-operative CT scan from the fourth lumbar vertebra to the tibial plateaus was compared to a similar post-operative CT scan performed after a minimum of 2 years after THA. Results: THA implantation caused significant post-operative changes in terms of the rotation height (2 mm lowering; p = 0.003); center of rotation medialization (10 mm medialization; p &lt; 0.001); femoral offset (11 mm increase; p &lt; 0.001); femoral antetorsion (22° internal rotation; p &lt; 0.001), and hip internal rotation (9° internal rotation; p &lt; 0.001). The femoral axis angle deviated in the valgus (5.5° ± 1.1°, p &lt; 0.001) and the mechanical lateral distal femoral angle deviated in the varus (86° ± 2.7°, p = 0.001). The pelvic–tibial alignment changed from 88.2° ± 11.7° to 96° ± 9.3° (p &lt; 0.001). Patellar alignment was not influenced. Conclusions: In conclusion, THA imposes significant changes in low-grade dysplastic hips: all the modifications tend to neutralize the coronal alignment and, mostly, the rotational alignment, without substantial and durable variations of the patellofemoral joint. Large clinical trials should confirm whether radiological changes impact anterior knee pain and patellar stability.

Sting and evaluation of a prototype of a mobility trainer: Verticalizer for children (2 to 7 years) weighing up to 20 kg.

The prototype of mobility trainer-verticalizer (hereinafter - PMTV) is designed to develop existing movements caused by individual physical conditions and disease damage, as close as possible to the natural biomechanics of a healthy person. The aim is to make the equipment comfortable, simple, suitable for everyday use in a variety of environments, from medical institutions to the patient's home, and customizable according to the anthropometric data of the growing child. To investigate and evaluate the technical characteristics and feasibility of a PMTV for children (2 to 7 years) weighing up to 20 kg. Empirical research method (anthropometric measurements); quantitative research method (survey); qualitative research method (interviews). The PMTV is suitable for use with children aged 2 to 7 years, although children with various disabilities may have heights, weights and other anthropometric data that fall far below or exceed the healthy standard. The exercise with the use of a PMTV had a positive effect on muscle tone, with a decrease in muscle tone in both the upper and lower limbs. An increased range of motion (hereinafter - ROM) of shoulder flexion and abduction was observed. In the lower limb, there was an improvement in the ROM of hip internal and external rotation and the flexion and extension of knee. Physiotherapy using PMTV had a positive effect on the subject's limb volume and muscle tone, a positive effect on the subject's passive ROM, and a positive effect on the subject's gross motor function.

Hip Muscle Strength, Range of Motion, and Functional Performance in Young Elite Male Australian Football Players.

Hip and groin injuries are common in field sports such as football, with measurement of hip strength and range of motion (ROM) recommended for assessment of these conditions. We aimed to report hip strength, hip ROM, and functional task performance in young elite Australian football athletes. Cross-sectional study. Fifty-eight newly drafted Australian Football League athletes completed hip abduction, adduction, internal rotation, external rotation, and flexion strength testing with an adjustable stabilized or hand-held dynamometer. Hip internal rotation and external rotation, bent knee fall out, and ankle dorsiflexion ROM were also measured. Players completed hop for distance, side bridge, and star excursion balance functional tests. We compared findings between the dominant and nondominant limbs. We found small deficits unlikely to be clinically meaningful in the dominant limb for hip abduction and adduction strength, and a small deficit in the nondominant limb for external rotation strength and side bridge time. Athletes had lower hip internal rotation (mean difference 2.56°; 95% confidence interval, 0.87 to 4.26) and total rotation ROM (2.03°; 95% confidence interval, 0.06 to 4.01) on the dominant limb. There were no meaningful differences between dominant and nondominant limbs for hip strength, ROM, or functional tests. Our results may be used for benchmarking young male Australian football athletes when targeting optimal strength and returning from injury.

Recovery in Hip Range of Motion in Young Flexibility Athletes 1 Year After Periacetabular Osteotomy.

Background: Periacetabular Osteotomy (PAO) is a well-established surgical intervention for the treatment of hip dysplasia. Purpose: Our primary objective was to assess whether a group of young flexibility athletes who underwent PAO for hip dysplasia recovered their pre-operative hip range of motion (ROM) within 1 year of surgery. Our secondary objective was to compare hip ROM recovery between a group of young flexibility athletes and a group of non-flexibility athletes who underwent PAO for hip dysplasia. Results: In our study, 100% of flexibility athletes regained preoperative hip external rotation at 1-year post-operation. This was also the first plane of motion to return to preoperative motion in flexibility athletes. A significantly higher percentage of non-flexibility athletes regained their preoperative hip internal rotation compared to flexibility athletes (100% compared to 54%; P = .02), but not flexion or external rotation at 1-year post-operation. Conclusion: Our findings may help providers to set expectations regarding the recovery of hip ROM in flexibility athletes who undergo PAO for hip dysplasia.Level of Evidence: Level IV.

Predictors of Changes in Pelvic Rotation after Surgery with or without Femoral Derotational Osteotomy in Ambulatory Children with Cerebral Palsy.

Asymmetry of pelvic rotation affects function. However, predicting the post-operative changes in pelvic rotation is difficult as the root causes are complex and likely multifactorial. This retrospective study explored potential predictors of the changes in pelvic rotation after surgery with or without femoral derotational osteotomy (FDRO) in ambulatory children with cerebral palsy (CP). The change in the mean pelvic rotation angle during the gait cycle, pre- to post-operatively, was examined based on the type of surgery (with or without FDRO) and CP distribution (unilateral or bilateral involvement). In unilaterally involved patients, pelvic rotation changed towards normal with FDRO (p = 0.04), whereas patients who did not undergo FDRO showed a significant worsening of pelvic asymmetry (p = 0.02). In bilaterally involved patients, the changes in pelvic rotation did not differ based on FDRO (p = 0.84). Pelvic rotation corrected more with a greater pre-operative asymmetry (β = -0.21, SE = 0.10, p = 0.03). Sex, age at surgery, GMFCS level, and follow-up time did not impact the change in pelvic rotation. For children with hemiplegia, internal hip rotation might cause compensatory deviation in pelvic rotation, which could be improved with surgical correction of the hip. The predicted changes in pelvic rotation should be considered when planning surgery for children with CP.