NEUROGRAPHIC ASSESSMENT OF INTRAMEDULLARY MOTONEURON LESIONS IN CERVICAL SPINAL-CORD INJURY - CONSEQUENCES FOR HAND FUNCTION

Examination of hand function and neurography of the median- and ulnar nerves was performed in 15 patients with acute and 26 patients with ch ronic tetraplegia due to cervical spinal cord injury (SCI). 30% of pat ients showed a mild and 20% a severe axonal lesion of motor fibres of both nerves. The latter is caused by intramedullary damage of ventral horn cells and anterior nerve roots as neurographic examination of sen sory nerve fibres was normal in these patients. The most frequent and severe nerve lesion was present in those with lower cervical spinal co rd injuries (C6/7-Th1) where the median and ulnar nerves originate. In the latter patients the development of active hand function, which en ables the patient to perform active grasping movements, was closely re lated to the result of neurography, already early after trauma. The re sults of median and ulnar neurography in tetraplegia due to cervical S CI allow to differentiate between intramedullary damage of motoneurone s and the anterior nerve roots (peripheral nervous system) or the pyra midal tract fibres (central nervous system) within the spinal cord res ponsible for the paresis of the intrinsic hand muscles. Neurography is of prognostic value in cervical SCI to predict the outcome of hand fu nction and therefore influences the appropriate occupational therapy a nd the program and aims of rehabilitation.