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Objective. To date there is only limited knowledge about the wearing time of orthoses. Ankle-foot orthoses (AFOs) have not been studied with this research question. Additional influences of the orthotic design as well as weekdays and the weekend are also unknown. Design. Monocentric, clinically prospective intervention study. Patients. Inclusion of 10 patients with bilateral spastic cerebral palsy. Methods. Equipment of all subjects with a dynamic ankle-foot orthosis (DAFO) and modular shank supply (MSS, dynamic elastic shank adaptation or ground reaction AFO). Integration of temperature sensors for recording the wearing time for a period of 3 months. Results. The actual wearing time was below the recommendations on actually worn days as well as the average of the entire study period. In addition, the actual usage in terms of days and hours was well below the recommendations. The wearing time showed differences between weekdays and weekend. Differences between DAFO and MSS were not detectable. Conclusion. The actual usage behavior of ankle-foot orthoses differs from the recommendations of the prescriber. This applies to both DAFOs and modular use with shank supplies. Environmental factors may have a significant impact on wearing times on weekdays and the weekend.

Introduction A unilateral transfemoral amputation (TFA) has a major impact on function. A leg-length discrepancy is the primary structural change, accompanied by the loss of lower-limb muscle volume and function. Prostheses can help individuals with a TFA to regain function, but such individuals still do not reach the functional level of unimpaired peers and exhibit gait deviations. This study gives insight into the causality between residual limb strength and gait deviations in individuals with a TFA. Methods A convenient sample of 13 male individuals with a TFA (38.0 ± 12.6y; 179.7cm ± 6.5cm; 82.9kg ± 12.4kg) was recruited for this study. One participant with TFA was excluded, as he differed from the rest of the cohort, in residual limb length and the use of walking aids. A cohort of 18 unimpaired subjects served as a reference group (REF; nine females; 44y ± 13y; 174cm ± 9cm; 71kg ± 12kg). All participants underwent a conventional clinical gait analysis using a marker based 3D motion capture system and force platforms. Kinematics and kinetics were determined utilizing standard modelling methods. All subjects underwent a strength test, using a custom-made device to determine isometric moments of the hip joint in abduction, adduction, extension, and flexion. Peak values for maximum isometric moments for each movement direction and selected kinematic and kinetic values were derived from the results. Differences between subjects with TFA and unimpaired were compared using a Mann-Whitney U Test and associations between groups by Spearman's rank correlation.

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Objective: To compare biomechanical and clinical outcome of laterally wedged insoles (LWI) and an ankle-foot orthosis (AFO) in patients with medial knee osteoarthritis. Design: Single-centre, block-randomized, cross-over controlled trial. Setting: Outpatient clinic. Subjects: About 39 patients with symptomatic medial knee osteoarthritis. Interventions: Patients started with either LWI or AFO, determined randomly, and six weeks later changed to the alternative. Main measures: Change in the 1st maximum of external knee adduction moment (eKAM) was assessed with gait analysis. Additional outcomes were other kinetic and kinematic changes and the patient-reported outcomes EQ-5D-5L, Oxford Knee Score (OKS), American Knee Society Clinical Rating System (AKSS), Hannover Functional Ability Questionnaire – Osteoarthritis and knee pain. Results: Mean age (SD) of the study population was 58 (8) years, mean BMI 30 (5). Both aids significantly improved OKS (LWI P = 0.003, AFO P = 0.001), AKSS Knee Score (LWI P = 0.01, AFO P = 0.004) and EQ-5D-5L Index (LWI P = 0.001, AFO P = 0.002). AFO reduced the 1st maximum of eKAM by 18% ( P < 0.001). The LWI reduced both maxima by 6% ( P = 0.02, P = 0.03). Both AFO and LWI reduced the knee adduction angular impulse (KAAI) by 11% ( P < 0.001) and 5% ( P = 0.05) respectively. The eKAM (1st maximum) and KAAI reduction was significantly larger with AFO than with LWI ( P = 0.001, P = 0.004). Conclusions: AFO reduces medial knee load more than LWI. Nevertheless, no clinical superiority of either of the two aids could be shown.

MRI is an excellent diagnostic tool to evaluate fatty degeneration after TFA. The highest amount of fatty degeneration of the quadriceps muscle was monitored within the first 10 months. Early physiotherapy is important to strengthen the remaining stump muscles during rehabilitation.

A prototype of a powered knee orthotic device was developed to determine whether fractional external torque and power support to the knee relieves the biomechanical loads and reduces the muscular demand for a subject performing sit-to-stand movements. With this demonstrator, consisting of the subsystems actuation, kinematics, sensors, and control, all relevant sensor data can be acquired and full control is maintained over actuator parameters. A series-elastic actuator based on a direct current motor provides up to 30 Nm torque to the knee via a hinge joint with an additional sliding degree of freedom. For reasons of feasibility under everyday conditions, user intention is monitored by employing a noninvasive, nonsticking muscle activity sensor to replace electromyographic sensors, which require skin preparation. Furthermore, foot plates with force sensors have been developed and included to derive ground reaction forces. The actual knee torque needed to provide the desired support is based on an inverse dynamics model using ground reaction forces signals and leg kinematics. A control algorithm including disturbance feed forward has been implemented. A demonstration experiment with two subjects showed that 23 % of moment support in fact leads to a similar reduction in activation of the main knee extensor muscle.

Strong coupling between stump and socket will help the user controlling his prosthesis. Shear stress at the stump may increase in stump-socket interface stiffness and may be the reason for residual limb problems. Torsion adapters therefore may be beneficial for comfort and stump condition in individual cases.