Hip Internal Rotation Research Articles

Gluteal activation during squatting reduces acetabular contact pressure in persons with femoroacetabular impingement syndrome: A patient-specific finite element analysis

BackgroundFemoroacetabular impingement syndrome is a motion-related clinical disorder resulting from abnormal hip joint morphology. Mechanical impingement, in which the aspherical femoral head (cam morphology) abuts with the acetabular rim, is created with simultaneous hip flexion, internal rotation, and adduction. Impaired function of the gluteal muscles may be contributory to femoroacetabular impingement syndrome progression. The purpose of this study was to assess the influence of gluteal muscle recruitment on acetabular contact pressure during squatting in persons with cam femoroacetabular impingement syndrome. MethodsEight individuals (4 males, 4 females) with a diagnosis of cam femoroacetabular impingement syndrome underwent CT imaging of the pelvis and proximal femora, and a biomechanical assessment of squatting (kinematics, kinetics, and electromyography). Two maximal depth bodyweight squat conditions were evaluated: 1) non-cued squatting; and 2) cued gluteal activation squatting. Utilizing subject-specific electromyography-driven hip and finite element modeling approaches, hip muscle activation, kinematics, bone-on-bone contact forces, and peak acetabular contact pressure were compared between squat conditions. FindingsModest increases in gluteus maximus (7% MVIC, P < 0.0001) and medius (6% MVIC, P = 0.009) activation were able to reduce hip internal rotation on average 5° (P = 0.024), and in doing so reduced acetabular contact pressure by 32% (P = 0.023). Reductions in acetabular contact pressure occurred despite no change in hip abduction and increased bone-on-bone contact forces occurring in the cued gluteal activation condition. InterpretationOur findings highlight the importance of gluteal activation in minimizing mechanical impingement and provide a foundation for interventions aimed at preventing the development and progression of femoroacetabular impingement syndrome.

An Updated Model Does Not Reveal Sex Differences in Patellofemoral Joint Stress during Running.

Structure-specific loading may have implications in understanding the mechanisms of running related injury. As females demonstrate a prevalence of patellofemoral pain twice that of males, this may indicate differences in patellofemoral loads between males and females. Previous works investigating differences in patellofemoral joint stress have shown conflicting results, but the models employed have not used estimates of muscle forces or sex specific contact areas. The aim of this study was to examine sex differences in patellofemoral joint stress using an updated model to include estimates of quadriceps muscle force and sex-specific patellofemoral contact area. Descriptive Laboratory Study. Forty-five healthy recreational runners ran at a controlled speed down a 20-meter runway. Kinetic and kinematic data were utilized to estimate muscle forces using static optimization. Quadriceps muscle force was utilized with sex-specific patellofemoral joint contact area in a two-dimensional patellofemoral joint model to estimate patellofemoral joint stress. Multivariate tests were utilized to detect sex differences in patellofemoral loading and hip and knee kinematics. No differences were found between sexes in measures of patellofemoral loading or quadriceps force. Females displayed a reduced knee extension moment and greater hip adduction and internal rotation than males. The inclusion of static optimization to estimate quadriceps muscle force and sex-specific contact area of the patellofemoral joint did not reveal sex differences in patellofemoral joint stress, but differences in non-sagittal plane hip motion were detected. Therefore, two-dimensional patellofemoral models may not fully characterize differences in patellofemoral joint stress between males and females. Three-dimensional patellofemoral models may be necessary to determine if sex differences in patellofemoral joint stress exist. 3b.

Effect of Different Pelvic-Drop Exercises On Muscle Activity In Patients With Gluteus Medius Muscle Weakness

<h3>Research Objectives</h3> To determine the effects of pelvic-drop exercise with three different hip rotations on gluteus medius, tensor fasciae latae, gluteus maximus activity, and gluteus medius:tensor fasciae latae activity ratio in patients with gluteus medius weakness. <h3>Design</h3> Cross-sectional study. The effects of different hip rotation positions on hip abductor activity during pelvic-drop exercise were analyzed using a one-way repeated-measures analysis of variance. <h3>Setting</h3> University research laboratory. <h3>Participants</h3> Eighteen patients with gluteus medius weakness participated in the study. <h3>Interventions</h3> The patients performed three different forms of pelvic-drop exercise with neutral hip, hip internal rotation, and hip external rotation. <h3>Main Outcome Measures</h3> Surface electromyography was performed to quantify the activity of gluteus medius, tensor fasciae latae, and gluteus maximus. <h3>Results</h3> Pelvic-drop exercise with hip internal rotation showed significantly greater gluteus medius activity than pelvic-drop exercise with neutral hip and hip external rotation. Tensor fasciae latae also showed significantly greater activity during pelvic-drop exercise with hip internal rotation than pelvic-drop exercise with neutral hip. <h3>Conclusions</h3> Pelvic-drop exercise with hip internal rotation is recommended to stimulate greater gluteus medius activity while preserving gluteus medius:tensor fasciae latae muscle activity ratio. <h3>Author(s) Disclosures</h3> The authors declare no conflict of interest.

Movement Competency Screen: Rethinking the Rating

Background Dancers are at high risk of musculoskeletal disorders. There has been a growing interest in the last few years in pre-season screening using tools to evaluate movement competency, among which is the Movement Competency Screen (MCS). It is currently scored using a categorical 3-level rating system, but this method does not seem to take into account the load level of movements. A 5-level scoring system could potentially alleviate this problem. Hypothesis/Purpose For each scoring system, to investigate (1) the internal consistency, and (2) the association with transversus abdominis activation (TrA), hip muscle strength and with Functional Movement screen (FMSTM) total score. Study design Secondary analyses of a prospective cohort study. Methods One hundred and eighteen professional and preprofessional dancers evolving in ballet or contemporary dance were recruited. The MCS was performed and was scored according to the 3- and 5-level scoring systems. The key variables for movement competency that were considered for convergent validity were the activation ratio of the TrA evaluated with ultrasound imaging and hip strength assessed with a handheld dynamometer. Movement competency was also measured with the FMSTM. Results Internal consistency was higher for the 5-level scoring of the MCS items ( α=0.548) compared to the 3-level scoring system ( α=0.494). Multiple linear regressions showed that TrA activation, hip adductor strength, and FMSTM could significantly explain 24.0% of the variance for the 5-level scoring system of the MCS whereas hip internal rotator strength and FMSTM could explain only 16.4% of the variance for the 3-level scoring system. Conclusion The 5-level scoring system showed better metrologic properties in terms of internal consistency and concurrent validity and therefore, should be preferred over the 3-level scoring system in future research. Level of Evidence Level III

Kinetic and kinematic comparisons in high school pitchers with low and high pitch location consistency.

Although ball velocity has often been associated with increased kinetics at the upper extremity and risk of injury in youth and adolescent pitchers, it is unclear if the performance metric pitch location consistency has any positive or negative associations with pitching kinetics. High school pitchers (n=59) pitched 8-12 fastballs using 3D motion capture (480 Hz). Pitchers were divided into high-consistency (HiCon) and low-consistency (LoCon) groups based on the absolute center deviation of each pitcher's pitch to the center of the pitcher's mean pitch location. Ninety-five percent confidence ellipses with major and minor radii were constructed, and kinematics and kinetics were compared between groups. Compared with LoCon pitchers, HiCon pitchers had decreased lead hip flexion at elbow extension (40°±12° vs. 52°±13°, respectively, P=.008), and at foot contact, decreased back hip extension (-1° ±10° vs. -10° ±13°, respectively, P=.038) and increased back hip internal rotation (9°±15° vs. -2° ± 15°, respectively, P=.043). LoCon pitchers achieved maximum lead hip flexion earlier in the pitch (61.3%±23.2% vs. 75.8%±15.1%, respectively, P=.039). A multiregression model predicted 0.49 of variance in pitch location consistency using kinematic inputs. Pitchers who differ in pitch location consistency outcomes do not appear to demonstrate physiologically unsafe kinematics. High school pitchers who strive for improved pitch consistency can consider adjusting parameters of hip kinematics during early portions of the pitch.

Body asymmetries as risk factors for musculoskeletal injuries in dancesport, hip-hop and ballet dancers?

The study aimed to determine the incidence and expression of body asymmetries in dancers of three different dance styles: dancesport (n = 14), hip-hop (n = 21) and ballet (n = 20) and to examine how body asymmetries (muscle strength and power, stability and range of motion) are associated with musculoskeletal injuries occurring over the past 12 months. Cross-sectional and retrospective study. Maximal isometric voluntary contraction was measured for trunk, hip, knee and ankle movements. Participants performed a single leg stance, unilateral landing, weight bearing symmetry, squat and countermovement jump on force platforms. Passive range of motion was measured for hip, knee and ankle with two-arm goniometer or digital inclinometer (hip flexion, extension and rotations). A retrospective questionnaire was used to collect data on musculoskeletal injuries occurring in the last 12 months. Different dance styles were associated with different body asymmetries, including strength asymmetries (hip flexion and external rotation), agonist/antagonist asymmetries (trunk flexion/extension, hip abduction/adduction, ankle dorsi/plantar flexion) and hip adduction and internal rotation range of motion asymmetries. Moreover, strength asymmetries of hip flexion, adduction and abduction/adduction as well as stability asymmetries were associated with the total number of musculoskeletal injuries. The incidence of body asymmetries (> 10%) in dancesport, hip-hop and ballet dancers was confirmed, as well as the association of some asymmetries with self-reported injuries occurring over the last 12 months. The cause-effect relationship should be clarified by further studies.

Elevated hip adduction angles and abduction moments in the gait of adolescents with recurrent patellar dislocation.

Impaired hip kinematics and kinetics may incite patellar instability. This study tested the hypothesis that hip adduction and internal rotation angles during gait are higher in adolescents with recurrent patellar dislocations compared to healthy controls. Case-control study. Eighty-eight knees (67 patients) with recurrent patellar dislocation (mean age 14.8years ± 2.8 SD) were compared to 54 healthy knees (27 individuals, 14.9years ± 2.4 SD). Peak hip, knee and pelvis kinematics and kinetics were captured using 3D-gait analysis (VICON, 12 cameras, 200Hz, Plug-in-Gait, two force plates) and compared between the two groups. One cycle (100%) consisted of 51 data points. The mean of six trials was computed. Peak hip adduction angles and abduction moments were significantly higher in patients with recurrent patellar dislocation compared to the control group (p < 0.001 and 0.002, respectively). Peak internal hip rotation did not differ significantly. Elevated hip adduction angles and higher hip abduction moments in gait of adolescents with recurrent patellar dislocation may indicate an impaired function of hip abductors that contributes to patellar instability.

Effect of Ultrasound-Guided Percutaneous Neuromodulation of Sciatic Nerve on Hip Muscle Strength in Chronic Low Back Pain Sufferers: A Pilot Study.

Background: Limited hip internal rotation range of motion (IR-ROM) and hip abductor weakness are recognized in low back pain (LBP) sufferers. The main aim was to investigate the effect of a ultrasound (US)-guided percutaneous neuromodulation (PNM) technique on hip strength in people with LBP. A second purpose was to discover whether the location along the sciatic nerve, where percutaneous neuromodulation was applied, could influence the change of strength response in these patients. Methods: Sixty LBP sufferers were recruited and divided randomly into three groups. All participants received an isolated percutaneous electrical stimulation at one of three different locations of the sciatic nerve pathway (proximal, middle, and distal), depending on the assigned group. Pain intensity, hip passive IR-ROM, hip muscle strength, and the Oswestry disability index (ODI) were analyzed. All variables were calculated before the intervention and one week after the intervention. Results: All interventions significantly decreased pain intensity and improved the IR-ROMs, strength, and functionality after one week (p = 0.001). However, between-group (treatment x time) differences were reported for flexion strength in the non-intervention limb (p = 0.029) and ODI (p = 0.021), although the effect size was small (Eta2 = 0.1) in both cases. Conclusions: The application of an isolated intervention of the US-guided PNM technique may be a useful therapeutic tool to increase the hip muscle strength in patients with chronic LBP.

Comparison of hip strength in football players with hip and/or groin-related pain and healthy controls

Introduction: Muscle weakness and atrophy have been associated with longstanding joint pathology, and strength testing is often recommended during the physical examination of patients with hip/groin pain. The aim of this study was to compare peak strength in football players (soccer and Australian football) presenting with hip and/or groin-related pain with healthy controls. Methods: Male and female football players were recruited across Melbourne and Brisbane, Australia. Demographic information and two questionnaires; the Copenhagen Hip and Groin Outcome Score (HAGOS) and the International Hip Outcome Tool 33 (iHOT) were collected. Hand-held dynamometry was utilised to test isometric hip muscle strength across flexion, extension, abduction, adduction, internal and external rotation planes. Peak strength (N) and torque (Nm) were normalised to body mass and linear mixed effects models were used to investigate the relationship between strength and symptomatic hips. Results: 191 football players with hip and/or groin-related pain (mean [+/- SD] age, 27.8 ± 6.3 years) and 69 controls (mean [+/- SD] age, 27.3 ± 5.6 years) were include in this study. Of this, 293 symptomatic hips and 138 control hips were used for analyses. Results demonstrated peak adduction (-0.18 Nm/kg: 95% CI -0.27 to -0.08, P 0.001), external rotation (-0.06 Nm/kg: 95% CI -0.09 to -0.02, P 0.003) and internal rotation strength (-0.06 Nm/kg: 95% CI -0.10 to -0.03, P 0.001) were lower in symptomatic hips than control hips. Abduction strength was lower in symptomatic Australian football players hips than controls (-0.20 Nm/kg: 95% CI -0.33 to -0.06, P 0.004) but this was not observed in symptomatic soccer players hips (-0.05 Nm/kg: 95% CI -0.15 to 0.06, P 0.382). No difference was found between peak flexion strength (0.07 Nm/kg: 95% CI -0.15 to 0.01, P 0.103) or peak extension strength (-0.07 Nm/kg: 95% CI -0.18 to 0.05, P 0.249) in symptomatic hips and control hips. Discussion: The findings from this research suggest that hip adduction, internal and external rotation are lower in footballers with hip and/or groin related pain than controls irrespective of the sport played. Hip abduction strength was lower in symptomatic Australian Rules football players but not observed in soccer. Impact:•Findings from this research suggest common impairments are found in hip adduction, internal and external rotation in football players with hip and/or groin related pain than controls regardless of sport played.•Hip abduction strength was lower in symptomatic Australian Rules football players but not observed in soccer. My co-authors and I acknowledge this research was supported by an Australian National Health and Medical Research Council (NHMRC) project grant 1088683.

Comparing Functional Motor Control Exercises With Therapeutic Exercise in Wrestlers With Iliotibial Band Syndrome.

Iliotibial band syndrome (ITBS) is a common overuse injury in runners with parallels to our findings of overuse in Greco Roman wrestlers. Despite research indicating coordination and movement-based factors about the hip, no studies were found using functional motor control (FMC) in runners or wrestlers with ITBS. Thus, we compared FMC exercises and therapeutic exercises (TEs) on pain, function, muscle strength, and range of motion (ROM) in national-level Greco Roman wrestlers with ITBS. Controlled laboratory study. Sixty national-level Greco Roman wrestlers diagnosed with ITBS were randomly assigned to 8weeks of FMC exercises, TE, and a control group (20 individuals for each group). Pain (visual analog scale), function (triple hop test for distance, single-leg vertical jump test, and agility T test), muscle strength (handheld dynamometer), and ROM (goniometer) were measured at baseline and 8weeks after intervention as posttest. Although both interventions significantly reduced pain (P < .001, η2 = .87), improved function (triple hop test P = .004, η2 = .94; single-leg vertical jump P = .002, η2 = .93; and T test P < .001, η2 = .93) and strength (hip abduction (P < .001, η2 = .52), hip external rotation (P = .02, η2 = .95), knee flexion (P ≤ .001, η2 = .94), and knee extension (P < .001, η2 = .91) compared with the control group, FMC showed more significant improvements in comparison with TE. Significant differences (P = .001) were observed between FMC and TE compared with the control group in ROM outcome. However, TE was more effective than FMC in improving ROM hip abduction (P < .001, η2 = .93), hip adduction (P = .000, η2 = .92), hip internal rotation (P < .001, η2 = .92), and hip external rotation (P < .001, η2 = .93). FMC exercises were superior to TE in terms of pain, function, and muscle strength, whereas TE was more effective for improving ROM. FMC exercise is suggested as an effective intervention for improvement of the outcomes related to ITBS in national-level Greco Roman wrestlers.

Comparison between Hip Internal Rotation Assistive Device and Conventional Radiograph Positioning: An Experimental Study.

Plain anteroposterior radiograph of the hip plays an important role in diagnosing hip pathology. However, one of the most common mistakes is image distortion because the hip is externally rotated due to natural femoral neck anteversion. Thus, the lower extremities should be internally rotated by 15°-20°. The researchers developed a hip internal rotation assistive device and compared it with conventional radiograph positioning. A hip internal rotation assistive device was designed. This study consisted of 20 volunteers without clinical hip pathology. The volunteers were informed to do a hip radiograph twice to compare the efficacy of the developed device with a conventional positioning. The thickness of the lesser trochanter (TLT) was measured and interpreted by an orthopedist and a radiologist. Statistical significance and inter- and intra-observer reliabilities were analysed. According to the orthopaedist's measurement, the mean TLT distance was 4.42 + 3.2mm and 4.97 + 3.16mm for the conventional technique and assistive device, respectively, without statistical significance between both groups (p = 0.05). Consistent with the musculoskeletal radiologist, the mean TLT distance was 4.00 + 2.06mm for the conventional technique and 3.92 + 2.27mm for the assistive device, without statistical significance between both groups (p = 0.56). Intra-observer reliability was 0.900 and 0.898 for the orthopaedist and the radiologist, respectively. Interobserver reliability of the assistive device and conventional technique were 0.800 and 0.588, respectively. The efficacy of the developed device was similar to that of the conventional technique. Inter/intra-observer reliabilities were at a good agreement level in both methods. The developed device would also be useful in clinical applications, especially in decreasing unnecessary radiation exposure of medical personnel.

Physical functions, to be or not to be a risk factor for osteochondritis dissecans of the humeral capitellum?

Physical risk factors for osteochondritis dissecans (OCD) of the humeral capitellum in young baseball players have not been fully elucidated. We aimed to identify the risk factors for capitellar OCD in baseball players aged 8-14 years. Between December 2018 and December 2019, young baseball players were recruited from 8 regional baseball leagues. Ultrasonography and physical assessments were performed preseason and at the end of the study period. Bilateral passive ranges of motion (ROM) of horizontal adduction of the shoulders, internal rotation (IR) of the hips, and the thoracic kyphosis angle were measured. 1-year follow-ups were scheduled to determine the occurrence of OCD. Players with OCD were categorized into an OCD group; those without OCD and any elbow pain for one year were categorized into a non-injured group. The players' baseline data (age, sex, position in baseball, and Rohrer's Index) were analyzed using univariate analyses. Their physical parameters were analyzed using two-way analysis of variance with repeated measures to investigate OCD-related risk factors. In total, 3651 baseball players attended the 1-year follow-up. Of these, 71 (1.9%) players had OCD of the humeral capitellum. In the OCD group, a significant association was found at baseline and at the end of the study period between a higher Rohrer index at the baseline and a smaller hip IR ROM on the nondominant side. Loss of hip IR ROM on the nondominant side is a newly discovered risk factor related to physical function in the development of OCD.

Validity and Reliability of a Novel Smartphone Tele-Assessment Solution for Quantifying Hip Range of Motion.

Tele-health has become a major mode of delivery in patient care, with increasing interest in the use of tele-platforms for remote patient assessment. The use of smartphone technology to measure hip range of motion has been reported previously, with good to excellent validity and reliability. However, these smartphone applications did not provide real-time tele-assessment functionality. We developed a novel smartphone application, the TelePhysio app, which allows the clinician to remotely connect to the patient's device and measure their hip range of motion in real time. The aim of this study was to investigate the concurrent validity and between-sessions reliability of the TelePhysio app. In addition, the study investigated the concurrent validity, between-sessions, and inter-rater reliability of a second tele-assessment approach using video analysis. Fifteen participants (nfemales = 6) were assessed in our laboratory (session 1) and at their home (session 2). We assessed maximum voluntary active hip flexion in supine and hip internal and external rotation, in both prone and sitting positions. TelePhysio and video analysis were validated against the laboratory's 3-dimensional motion capture system in session 1, and evaluated for between-sessions reliability in session 2. Video analysis inter-rater reliability was assessed by comparing the analysis of two raters in session 2. The TelePhysio app demonstrated high concurrent validity against the 3D motion capture system (ICCs 0.63-0.83) for all hip movements in all positions, with the exception of hip internal rotation in prone (ICC = 0.48, p = 0.99). The video analysis demonstrated almost perfect concurrent validity against the 3D motion capture system (ICCs 0.85-0.94) for all hip movements in all positions, with the exception of hip internal rotation in prone (ICC = 0.44, p = 0.01). The TelePhysio and video analysis demonstrated good between-sessions reliability for hip external rotation and hip flexion, ICC 0.64 and 0.62, respectively. The between-sessions reliability of hip internal and external rotation for both TelePhysio and video analysis was fair (ICCs 0.36-0.63). Inter-rater reliability ICCs for the video analysis were 0.59 for hip flexion and 0.87-0.95 for the hip rotation range. Both tele-assessment approaches, using either a smartphone application or video analysis, demonstrate good to excellent concurrent validity, and moderate to substantial between-sessions reliability in measuring hip rotation and flexion range of motion, but less in internal hip rotation in the prone position. Thus, it is recommended that the seated position be used when assessing hip internal rotation. The use of a smartphone to remotely assess hip range of motion is an appropriate, effective, and low-cost alternative to the face-to-face assessments. This method provides a simple, cost effective, and accessible patient assessment tool with no additional cost. This study validates the use of smartphone technology as a tele-assessment tool for remote hip range of motion assessment.

Dynamic Taping Improves Landing Biomechanics in Young Volleyball Athletes.

Poor landing biomechanics such as hip adduction, internal rotation, and knee valgus have been recognized as modifiable risk factors of anterior cruciate ligament (ACL) injury. Dynamic taping is a newly developed technique with better elasticity and extensibility, which could change the landing biomechanics. The purpose of this study was to identify whether dynamic taping could improve lower limb biomechanics in athletes. Forty-two high school volleyball athletes (21 males and 21 females) participated in the study. Biomechanical properties, including the landing error scoring system (LESS) and anterior–posterior knee laxity, were evaluated before and after the application of dynamic tape while athletes performed the jump-landing task. As a result, we found that dynamic tape significantly reduced the faulty landing strategy by an average of 0.64 errors in all volleyball athletes. The effect induced by dynamic tape was more prominent in female athletes and high-risk athletes (1.1 errors). Furthermore, the application of dynamic tape improved anterior–posterior knee laxity, especially in female athletes (p < 0.001). In conclusion, we found that dynamic tape provided a short-term, passive, and clinically significant means to normalize inadequate biomechanics during landing in athlete groups, which could have a protective effect and further alleviate the risk of ACL injury.

Biomechanical Asymmetry of Strength and Dynamic Balance Kinetics in Middle-Ages with Adhesive Capsulitis of the Hip.

The representative clinical features of adhesive capsulitis of the hip (ACH) are restricted range of motion (ROM) and pain. However, reports on kinetics such as strength and dynamic balance that explain physical functions are rare. This study compared subjective hip scores using Copenhagen Hip and Groin Outcome Score (HAGOS) and ROM using a manual goniometer as well as strength using isokinetic equipment, and dynamic balance through the Y-balance test, between patients with ACH and healthy individuals. Data of 193 middle-aged participants (men: 99 and women: 94) were analyzed. The ACH group scored significantly lower in all six HAGOS sub-sections. Hip joint flexion, abduction, internal and external rotation ROM were significantly lower in ACH compared to healthy group. These results were the same for men and women. In the strength of men and women, flexion, adduction, and abduction, and dynamic balance in all three directions were significantly decreased in ACH. Meanwhile, there were no significant between-group differences in the functional decrease in extension and adduction of ROM, and extension strength. In conclusion, subjective evaluation and dynamic balance of patients with ACH were decreased in the all parts. In ROM, flexion, abduction, internal rotation, and external rotation were restricted except for extension and adduction. Men and women with ACH maintained extensor strength, but had weakened strength in flexion, adduction and abduction. This information will be useful for therapists to understand the biomechanical properties of ACH and to design effective rehabilitation programs.

46 Universal calcinosis in juvenile dermatomyositis: a case report

BackgroundDermatomyositis (DM) is an inflammatory myopathy that is often severe and affects children (juvenile DM) in 50% of cases. Subcutaneous calcinosis is seen in 30–70% of juvenile DM and often poses a problem in terms of treatment.We report a patient with diffuse subcutaneous calcinosis in juvenile DM.ObservationThe patient is K.S, a 17-year-old girl, with background history of congenital heart disease (atrial septal defect), which was corrected surgically in 2021. Since the age of 13, she has had DM for which she has received corticosteroid therapy at a dose of 2 mg/kg/day and improved clinically. The clinical examination reveals subcutaneous nodules in the arms, forearms, phalanx of the right index finger, inner thigh, knees and legs, associated with reduced range of movement of the right elbow (presence of calcifications) and limitation of internal rotation of the right hip.Laboratory investigations showed no inflammatory syndrome, the muscle enzymes and electromyogram were normal. Radiographs showed calcifications at the sites with subcutaneous nodules.Bone densitometry showed a decrease in bone mineral density (Z score= -3.4 standard deviation at the lumbar spine). The thoracic CT scan showed interstitial lung disease.The patient was managed with pamidronic acid for the diffuse calcinosis. She is also on diltiazem for Raynaud's phenomenon and hydroxychloroquine.ConclusionSubcutaneous calcinosis is diffuse in our patient. Treatment with bisphosphonates (pamidronic acid) is recommended.

Spine and lower body symmetry during treadmill walking in healthy individuals-In-vivo 3-dimensional kinematic analysis.

Although it is relevant to understand spine and lower body motions in healthy individuals for a variety of applications, such as clinical diagnosis, implant design, and the analysis of treatment outcomes, proper assessment and characterization of normative gait symmetry in healthy individuals remains unclear. The purpose of this study was to investigate the in vivo 3-dimensional (3D) spine and lower body gait symmetry kinematics during treadmill walking in healthy individuals. Sixty healthy young adults (30 males and 30 females) were evaluated during normal and fast treadmill walking using a motion capture system approach. Statistical parametric mapping and the normalized symmetry index approaches were used to determine spine, pelvis, and lower body asymmetries during treadmill walking. The spine and pelvis angular motions associated with the left and right lower limb motions, as well as the left and right lower extremity joint angles were compared for normal and fast treadmill walking. The lower lumbar left-right rotation (5.74±0.04°) and hip internal rotation (5.33±0.18°) presented the largest degrees of asymmetry during normal treadmill. Upper lumbar left-right lateral flexion (1.48±0.14°) and knee flexion (2.98±0.13°) indicated the largest asymmetries and during fast treadmill walking. Few asymmetry patterns were similar between normal and fast treadmill walking, whereas others appeared either only during normal or fast treadmill walking in this cohort of participants. These findings could provide insights into better understanding gait asymmetry in healthy individuals, and use them as reference indicators in diagnosing and evaluating abnormal gait function.

08 Juvenile idiopathic arthritis and corticosteroid-induced osteonecrosis of the femoral head

Abstract Background Juvenile idiopathic arthritis (JIA) is a group of inflammatory joint diseases that begin before the age of 16. Depending on the clinical form of JIA, medical treatment may involve long-term high-dose corticosteroid therapy, which may lead to aseptic femoral head osteonecrosis of patients. We report three observations of aseptic osteonecrosis of the femoral head in patients followed for JIA. 1st observation: Mr I.A, aged 19 years, presented with ankylosing spondylitis with peripheral involvement, with a juvenile onset, for which he had received a high dose of corticosteroids at an average of 1.5 mg/kg/day since the age of 15 months on an intermittent basis. Clinically, the patient had a height of 1.65, a right limp when walking and limited movement of the right hip with a Lequesne algofunctional index of 10.5 (significant disability). MRI of the pelvis showed aseptic osteonecrosis of the right femoral head (ONATF), Arlet and Ficat stage 3. Observation 2: Mr A.B, 27-year-old, had systemic JIA since the age of 12. He received corticosteroid therapy at an average dose of 1 mg/kg/day intermittently. Clinically the patient presents with signs of cortisone impregnation (a cushingoid face, purple stretch marks, thin skin) and bilateral cataract. The patient walks with the help of a crutch. The examination of the hips revealed a limitation of mobility of the left hip with a Lequesne algo-functional index of 18.5. Bone densitometry showed a decrease in bone density. Standard radiographs noted a left ONATF, Arlet and Ficat stage 4 with L4 and L5 vertebral fractures. 3rd Observation: Mr B.M, 26-year-old, followed for systemic JIA since the age of 14. He was treated with high dose corticosteroids at a rate of 1 mg/kg/day. The clinical examination revealed unevenness of the lower limbs, a left limp when walking, limited internal rotation and abduction of the right hip. The patient also had multiple inflammatory acne lesions and a bilateral cataract. Bone densitometry showed a decrease in bone density. Standard radiography showed bilateral ONATF, stage 3 on the right and 4 on the left according to Arlet and Ficat's classification, which required the placement of a double total hip replacement. Conclusion Corticosteroid therapy is one of the main risk factors for non-traumatic aseptic osteonecrosis. Our three patients presented with ONAT with major disability following long-term corticosteroid therapy. The efficacy of corticosteroids is well established but they should be used with caution to avoid side effects

Hip Range of Motion and Strength in Male Athletes with Stage 1 Osteitis Pubis: A Cross-Sectional and Correlational Study.

Background: The objectives of this study were: (1) to determine whether athletes with stage 1 osteitis pubis (OP) present differences in hip range of motion (ROM) and muscle strength, between both sides and compared with healthy athletes; (2) to investigate the relationship between the internal rotation (IR) ROM and pain intensity and physical function. Methods: a cross-sectional and correlational study was designed, in which 30 athletes (15 athletes with stage 1 OP and 15 healthy athletes) were included. Pain intensity, physical function, hip ROM and hip muscle strength were assessed. Results: The ROM assessment reported significant differences between both groups in the IR, external rotation (ER) and adduction (ADD) ROM of the painful side (PS) (p < 0.05). The OP group showed differences between both sides in IR ER and ADD ROM (p < 0.05). No statistically significant differences were found between or within groups in the maximum isometric strength of the hip (p > 0.05). A strong negative correlation between pain intensity and IR ROM (r = −0.640) and a strong positive correlation between physical function and IR ROM (r = 0.563) were found in the OP group. Conclusions: Male athletes with stage 1 OP present a hip IR, ER and ADD ROM limitation in the PS compared to non-PS and to healthy athletes. IR ROM is correlated to pain intensity and physical function in athletes with stage 1 OP.

On-Field Biomechanical Assessment of High and Low Dive in Competitive 16-Year-Old Goalkeepers through Wearable Sensors and Principal Component Analysis.

Diving saves are the main duty of football goalkeepers. Few biomechanical investigations of dive techniques have been conducted, none in a sport-specific environment. The present study investigated the characteristics of goalkeepers’ dive in preferred (PS) and non-preferred (nPS) side through an innovative wearables-plus-principal-component analysis (PCA) approach. Nineteen competitive academy goalkeepers (16.5 ± 3.0 years) performed a series of high and low dives on their PS and nPS. Dives were performed in a regular football goal on the pitch. Full-body kinematics were collected through 17 wearable inertial sensors (MTw Awinda, Xsens). PCA was conducted to reduce data dimensionality (input matrix 310,878 datapoints). PCA scores were extracted for each kinematic variable and compared between PS and nPS if their explained variability was >5%. In high dive, participants exhibited greater hip internal rotation and less trunk lateral tilt (p < 0.047, ES > 0.39) in PS than nPS. In low dives, players exhibited greater ipsilateral hip abduction dominance and lower trunk rotation (p < 0.037, ES > 0.40) in PS than nPS. When diving on their nPS, goalkeepers adopted sub-optimal patterns with less trunk coordination and limited explosiveness. An ecological testing through wearables and PCA might help coaches to inspect relevant diving characteristics and improve training effectiveness.