Hereditary Motor Sensory Neuropathy: Understanding Function Using Motion Analysis

Abstract

Hereditary motor sensory neuropathies, or Charcot-Marie-Tooth disease, represent a heterogeneous group of inherited neuropathies that are characterized by progressive wasting and resulting weakness of the distal muscles in the legs and arms. Lower extremities are typically initially effected and, as result, impact ambulation. At present there is no curative treatment available; therefore, treatment of gait issues is often sought to help with ambulation and activities of daily living. Computerized motion analysis techniques have improved our understanding of the various presentations of hereditary neuropathies and can assist in making optimal treatment decisions to improve gait. These presentations include three distinct ankle variations: excessive equinus (toe walking), cavo-varus (lateral border weight bearing), and flail foot (heel weight bearing) patterns. As each patient presents differently in terms of deformity specifics and severity, a detailed analysis that describes ankle/foot function during gait in terms of foot pressures, muscle activity, kinematics, and kinetics along with clinical examination information such as muscle strength and passive range of motion is very beneficial. Assessment of treatment outcomes from bracing to orthopedic surgery as well as disease progression which also varies person to person is necessary to develop evidence-based treatment indications and goals. Motion analysis can play a very important role in the assessment of inherited neuropathies on both an individual patient basis and in research with the ultimate goal of improving treatment outcomes.