Relationship between various clinical signs in lesions of the descending motor system (a statistical study).

Classical upper motor neuron disease findings weakness, hypertonus, hyperreflexia, clonus and decreased skill), in patients with lesions of the descending motor system as manifested by extensor plantar responses, were statistically analyzed to determine if there was a relationship between them. In the upper extremity a highly significant relationship existed between weakness and decreased skill (p<0.005). In the lower extremity a highly significant relationship was noted between hyperreflexia and clonus (p<0.005) and a significant relationship existed between weakness and hypertonus (0.025>p>0.010). No statistically significant relationship was noted between the other findings in either the upper or the lower extremity.