OBJECTIVE: To describe the clinical and histopathologic picture of a 
childhood-onset, severe variant of scapuloperoneal MD with rigidity of the 
spine.
BACKGROUND: Rigidity of the spine is a feature of numerous syndromes, including 
X-linked Emery-Dreifuss MD, Bethlem myopathy, and the rigid spine syndrome. 
These are, however, relatively static or very slowly progressive neuromuscular 
disorders, usually associated with preserved ambulation into adult life.
PATIENTS AND METHODS: Five unrelated children (three boys and two girls) 
presented in the first 2 years of life with poor neck control, waddling gait, 
and frequent falls. Early wasting of the distal leg muscles, biceps, triceps, 
and neck muscles was noted in all patients, and all had contractures and severe 
rigidity of the spine. The condition progressed rapidly, and all patients lost 
ambulation before the age of 8 years. Cardiac function was normal in all.
RESULTS: Creatine kinase was moderately elevated in all, and muscle biopsy 
specimens showed nonspecific dystrophic changes with normal expression of 
dystrophin, the sarcoglycans, and laminin alpha2, alpha5, beta1, and gamma1 
chains. Emerin expression was normal in two of the boys whose tissue was 
available for study.
CONCLUSIONS: The distribution of weakness, wasting, and contractures of the 
patients described resembled Emery-Dreifuss MD, but the rapid progression of 
weakness and contractures and the involvement of both sexes together with normal 
emerin expression suggest that this form is not X-linked Emery-Dreifuss MD. We 
suggest that these patients represent a severe MD characterized by early onset 
distal wasting and severe rigidity of the spine, with probable autosomal 
recessive inheritance.