Article révisé par les pairs
Résumé : Neuromuscular biopsies were obtained in 10 patients with traumatic spinal cord lesions at various levels and in one patient with cerebral lesions due to a long-lasting coma. In all cases, there was a rapid onset of atrophy of both fiber types, with numerous transmissional type III and intermediate fibers. Only the two patients with cervical lesions had an increased terminal innervation ratio suggesting denervation. Our observations do not support the hypothesis of a transneuronal degeneration. These changes cannot be related to disuse only as the atrophy does not preferentially involve type II fibers. The underlying neural mechanism of spasticity in muscle of patients with cortico-spinal lesions could explain the change of the histochemical pattern of the muscle fibers.