Congenital segmental spinal muscular atrophy: a case report

Spinal muscular atrophies are genetic disorders in which anterior horn cells in the spinal cord and motor nuclei of the brainstem are progressively lost. We present a patient with arthrogryposis due to congenital spinal muscular atrophy predominantly affecting the upper limbs. Spinal muscular atrophies with onset at birth may be a cause of arthrogryposis. Localized forms of neurogenic arthrogryposis have been divided into cervical and caudal forms. Our case is similar to the cases described by Hageman et al (J Neurol Neurosurg Psychiatry 1993;56:365-368): severe symmetric lower motor neuron deficit in the upper extremities at the time of birth, no history of injury to the cervical spinal cord or the brachial plexus during delivery, and severe muscle wasting suggesting chronic denervation in utero. Because there was improvement of our patient's situation, her disease was also possibly nonprogressive and sporadic. To our knowledge, this is the first reported case of a Turkish patient with congenital cervical spinal muscular atrophy. Congenital cervical spinal muscular atrophy affecting predominantly the upper limbs is a relatively rare form of motor neuron disease and should be considered in the differential diagnosis of infants with congenital contractures and severe muscle weakness by wasting mainly confined to the upper limbs.