Simulation of double-leg stance in conditions of limited hip mobility

Hip osteoarthritis is one of the most common and disabling conditions affecting elderly. Coxarthrosis accompanied by impairment amortization properties cartilage, its thinning destruction, appearance pain syndrome, impaired motor functions due to a decrease in muscle strength development stable flexion-adduction contractures, which change congenital programs, and, with prolonged course degenerative disease, lead formation pathological habits. Objective: determine required muscles lower limb limited hip mobility support an upright posture double-leg stance. Materials methods. The work extremities under restricted was simulated using OpenSim 4.0 software. It based on ToyLandingModel, has contact geometry objects fix model area. Four models were created: norm (without limitation joint mobility), 2 — adduction 5°, 3 7°, flexion 10°, 4 20°, shortening femur bones cm. Results. found that insignificant contractures joint, changes slightly during With are observed almost all limb. There some peculiarities contractures. All around thigh reduce necessary maintain balance, while leg muscles, contrary, increase several times. For example, m.medial gastrocnemius contracture develops10 times higher compensatory force (200 N) than normal (20 N), although resources 1500 N, it very demanding posture. Similarly, m.tibialis posterior require (threefold), but antagonist anterior, reduces contraction average 100 N. Conclusions. According data conducted modeling stance mobility, proved movements nature entire pelvis. analysis obtained results showed restriction stabilization increases muscles. That is, there imbalance