Abstract
Four patients with mucolipidosis type III, three of them brothers, were seen initially in the first two decades of life. Their main symptoms were carpal tunnel syndrome, trigger fingers and generalized joint stiffness. Radiographs showed spinal deformities and hip dysplasia, but these were not causing pain. Carpal tunnel syndrome was treated surgically but joint stiffness and hip and knee contractures were managed by physiotherapy. Up to the age of 24 none of these patients has had pelvic osteotomy for hip dysplasia; this operation, not yet reported in mucolipidosis type III, may eventually be necessary.