Pelvic bone defect in patients with severe congenital dysplasia of the hip (CDH) lead to abnormalities in lumbar spine and lower limb alignment that can determine total hip arthroplasty (THA) patients' outcome. These variables may be different in uni- or bilateral CDH. We compared the clinical outcome and the spinopelvic and lower limb radiological changes over time in patients undergoing THA due to uni- or bilateral CHD at a minimum follow-up of five years. Sixty-four patients (77 hips) undergoing THA due to severe CDH between 2006 and 2015 were analyzed: Group 1 consisted of 51 patients with unilateral CDH, and group 2, 113 patients (26 hips) with bilateral CDH. There were 32 females in group 1 and 18 in group 2 (p=0.6). The mean age was 41.6 years in group 1 and 53.6 in group 2 (p<0.001). We compared the hip, spine and knee clinical outcomes. The radiological analysis included the postoperative hip reconstruction, and the evolution of the coronal and sagittal spinopelvic parameters assessing the pelvic obliquity (PO) and the sacro-femoro-pubic (SFP) angles, and the knee mechanical axis evaluating the tibio-femoral angle (TFA). At latest follow-up, the mean Harris Hip Score was 88.6 in group 1 and 90.7 in group 2 (p=0.025). Postoperative leg length discrepancy of more than 5 mm was more frequent in group 1 (p=0.028). Postoperative lumbar back pain was reported in 23.4% of the cases and knee pain in 20.8%, however, there were no differences between groups. One supracondylar femoral osteotomy and one total knee arthroplasty were required. The radiological reconstruction of the hip was similar in both groups. The PO angle improved more in group 1 (p=0.01) from the preoperative to 6-weeks postoperative and was constant at 5 years. The SFP angle improved in both groups but there were no differences between groups (p=0.5). 30 patients in group 1 showed a TFA less than 10º and 17 in group 2 (p=0.7). Although the clinical outcome was better in terms of hip function in patients with bilateral CDH than those with unilateral CDH, the improvement in low back and knee pain was similar. Patients with unilateral dysplasia showed a better correction of the PO after THA. All spinopelvic and knee alignment parameters were corrected and maintained over time in most cases five years after THA

For clinical movement analysis, optical marker-based motion capture is the gold standard. With the advancement of AI-driven computer vision, markerless motion capture (MMC) has emerged. Validity against the marker-based standard has only been examined for lightly-dressed subjects as required for marker placement. This pilot study investigates how different clothing affects the measurement of typical gait metrics. Gait tests at self-selected speed (4 km/h) were performed on a treadmill (Motek Grail), captured by 9 cameras (Qualisys Miqus, 720p, f=100Hz) and analyzed by a leading MMC application (Theia, Canada). A healthy subject (female, h=164cm, m=54kg) donned clothes between trials starting from lightly dressed (LD: bicycle tight, short-sleeved shirt), adding a short skirt (SS: hip occlusion) or a midi-skirt (MS: partial knee occlusion) or street wear (SW: jeans covering ankle, long-sleeved blouse), the lattern combined with a short jacket (SWJ) or a long coat (SWC). Gait parameters (mean±SD, t=10s) calculated (left leg, mid-stance) were ankle pronation (AP-M), knee flexion (KF-M), pelvic obliquity (PO-M) and trunk lateral lean (TL-M) representing clinically common metrics, different joints and anatomic planes. Four repetitions of the base style (LD) were compared to states of increased garment coverage using the t-test (Bonferroni correction). For most gait metrics, differences between the light dress (LD) and various clothing styles were absent (p>0.0175), small (< 2SD) or below the minimal clinically important differences (MCID). For instance, KF-M was for LD=10.5°±1.7 versus MD=12.0°±0.5 (p=0.07) despite partial knee cover. AP-M measured for LD=5.2°±0.6 versus SW=4.1°±0.7 (p<0.01) despite ankle cover-up. The difference for KF-M between LD=10.5°±1.7 versus SWL=6.0°±0.9, SW and SWJ (7.6°±1.5, p<0.01) indicates more intra-subject gait variability than clothing effect. This study suggests that typical clothings styles only have a small clinically possibly negligible effect on common gait parameters measured with MMC. Thus, patients may not need to change clothes or be instructed to wear specific garments. In addition to avoiding marker placement, this further increases speed, ease and economy of clinical gait analysis with MMC facilitating high volume or routine application

Introduction and Objective. Slipped Capital Femoral Epiphysis (SCFE) is one of the most common hip disorders in children and is characterized by a proximal femoral deformity, resulting in early osteoarthritis. Several studies have suggested that SCFE patients after in situ fixation show an altered gait pattern. Early identification of gait alterations might lead to earlier intervention programs to prevent osteoarthritis. The aim of this study is to analyse gait alterations in SCFE patients after in situ fixation compared to typically developed children, using the Computer Assisted Rehabilitation Environment (CAREN) system. Materials and Methods. This is a cross-sectional, multi-center case-control study in the Netherlands. Eight SCFE patients and eight age- and sex-matched typically developed were included from two hospitals. Primary outcomes were kinematic parameters (absolute joint angles), studied with gait analysis using statistical parametric mapping (SPM). Secondary outcomes were spatiotemporal parameters, the Notzli alpha angle, muscle activation patterns (EMG), and clinical questionnaires (VAS, Borg CR10, SF-36, and HOOS), analyzed using non-parametric statistical methods. Results. Patients (mean BMI=28±9 kg/m. 2. ) showed altered gait patterns, with significantly increased external hip rotation and decreased downward pelvic obliquity during the pre-swing phase of the gait cycle compared to typically developed (mean BMI=22±3 kg/m. 2. ). Walking speed, cadence, % stance time, and step length were reduced in SCFE patients. Coefficient of variances of cadence, stance time, and step length were increased. Patients had a mean alpha angle of 64, SD=7.9. Clinical questionnaires showed that general health (SF-36) was 80±25, energy/fatigue (SF-36) was 67±15, pain (VAS) was 0±1.5, and total HOOS score was 85±18. Conclusions. SCFE patients after in situ fixation appear to have developed a compensation mechanism, showing slight alterations in gait parameters, good general health, little functional limitations of the hip, and no self-reported pain. Cam deformities, altered joint loading, and this compensation mechanism might influence long-term early osteoarthritis. BMI reduction should be implemented in care plans, as obesity might also play a role in unfavorable long-term outcomes

Summary. Movement analysis (IMA) and activity monitoring (AM) using a body-fixed inertia-sensor can discriminate patients with ankle injuries from controls and between patients of different pathology or post-injury time. Weak correlations with PROMs show its added value in objectifying outcome assessment. Introduction. Ankle injuries often result in residual complaints calling for objective methods to score outcome alongside subjective patient-reported outcome measures (PROMs). Inertial motion analysis (IMA) and activity monitoring (AM) using a body-fixed sensor have shown clinical validity in patients suffering knee, hip and spine complaints. This study investigates the feasibility of IMA and AM 1) to differentiate patients suffering ankle injuries from healthy controls, 2) to compare different ankle injuries, 3) to monitor ankle patients during recovery. Methods. 32 patients suffering ankle problems (ankle sprain, n=17, 42 ±26yrs; operatively managed ankle fracture, n=15, 44 ±17yrs) during short-term recovery (6weeks to 3months post-trauma) were compared to 22 matched healthy controls (41 ±13yrs). Function was measured using IMA: Gait, Sit-Stand (STS) and 10s one-leg Balance test (OLB) were performed while wearing a 3D inertia-sensor at the lower back. Physical activity was measured during 4 successive days using a 3D accelerometer (AM), attached at the upper leg. Validated algorithms were used to derive motion parameters (e.g. speed for gait, bending angle for STS, sway area for OLB, # steps for AM). Moreover three ankle specific questionnaires were completed: Manchester-Oxford Foot and Ankle Questionnaire (MOXFQ), Foot and Ankle Ability Measure (FAAM), AOFAS ankle-hindfoot score. Data was analysed using paired t-tests, one-way ANOVA and Pearson's r. Results. Both patient groups performed worse in function (IMA), activity (AM) and scales (PROM). Even at 3 months mean walking speed (−26%) and cadence (−9%) were slower while pelvic obliquity during ST (+18%) and sway during OLB (+230%) was higher than in controls (p<0.05). Activity was less regarding step/day (−31%) and sit-stand transfers (−11%, p<0.05). Also PROMs were significantly worse in patients (range 17–37%). Comparing in-between patients, significant differences were found in PROMs and function (IMA) with fracture patients walking slower (−30%) or showing more sway during one-legged balance (+250%). Mean activity scores (steps, bouts, cadence) were also less for fractures (p>0.05). During recovery, PROMs improved significantly, while function (IMA) and activity (AM) only showed small or selective improvements (e.g. 8° reduction in bending angle during ST, 20% increase in cadence). Only weak to moderate correlations were found between PROM, IMA (r-range: 0.32–0.79) and AM parameters (r-range: 0.31–0.71). Discussion & Conclusion. Function, physical activity and PROMs were impaired in patients with ankle injuries compared to healthy subjects, with the fracture group performing worse on IMA and PROMs than the sprain group. In this first study ever to measure activity in ankle patients, it was shown that e.g. fracture patients walk ca. half as many steps and bouts as age-matched controls even though at 6weeks they were unable to walk 20m without walking aids (floor effect of IMA function test). The lack of improvements in IMA and AM during recovery while PROMs improved significantly, together with the few and only weak-to-moderate correlations between PROMs, IMA and AM shows that subjective and objective recovery differ and highlight the added value of IMA and AM for objectifying routine clinical outcome assessment