[Functional and orthopaedic aspects of dystrophinopathies]

Although the clinical picture and the natural progression of Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD) differ, borderline forms exist. Classical orthopaedic treatment is based on self-rehabilitation (by the parents and the patient), physical therapy, posture alignment with orthotics, ergotherapy to set up technical aides, notably positioning in an electric wheelchair to provide more satisfactory autonomy. The functional aspect predominates over pure orthopaedics. Although surgical indications have evolved for the lower limbs, pelvic-spinal arthrodesis for treatment of scoliosis remains the reference treatment, but the methods have evolved since the advent of corticotherapy for DMD. Corticotherapy slows the progression of motor deficits, the age at which walking ability is lost is delayed (shifting from 10 years to 13-14 years depending on the studies), scoliosis progresses later, respiratory insufficiency is better controlled, and therefore survival is prolonged (between 20 and 40 years). However, although this functional aspect seems to respond better to the progress in overall treatment, it also results from a multidisciplinary approach to the disease. Nevertheless, assessment is required, not at a time t as reflected by the scales currently in use, but during daily activities as proposed by qualitative and quantitative monitoring seeking to model nyctohemeral functional motor skills. The principle is to characterize the type of activity (sitting, standing, lying down, walking), its duration, its intensity (walking speed), its frequency (number of activity changes, number of walking episodes), and their sequence (temporal sequence, organization of activity variation). The goal is to identify the variety of functional motor skills and their occurrence over time to determine whether treatment contributes a functional benefit and whether this benefit is put into practice daily.