Spina bifida occulta. Foot deformities, enuresis and vertebral cleft: clinical picture and neurophysiological assessment.

AIM: The aim of the study was to investigate the relationship between the clinical evidence of foot deformities in spina bifida occulta and the associated neurophysio-logical damage. METHODS: The authors studied 47 patients with foot deformities (37 flat foot, 10 pes cavus) and vertebral cleft, variably associated with enuresis, midline cutaneous lesions, and further orthopaedic deformities. An electrophysiological evaluation was performed in an attempt to investigate the peripheral nervous system in greater detail, including conventional motor and sensory nerve conduction, F-wave recording and electromyogram (EMG) testing. RESULTS: The peroneal nerve F wave latency was longer in patients with pes cavus than in those with flat foot (P<0.04). Conversely, the posterior tibial nerve F-wave latency was longer in patients with flat foot than in those with pes cavus (P<0.02). Needle EMG showed large amplitude motor unit potentials during voluntary recruitment in all patients, suggesting a neurogenic origin of these EMG changes. Neurophysiological study makes it possible to distinguish between myogenic and lower motor neuron involvement. The existence of some degree of spinal cord dysraphism may be pathophysiologically associated with foot deformities. CONCLUSION: Children with foot deformities and clinical evidence of occult spinal dysraphism should have a neuro-physiological assessment in order to obtain an early diagnosis and avoid ineffective foot surgery.