Progressive and Hereditary Diaphyseal Dysplasia

Abstract

Progressive diaphyseal dysplasia, since its original description by Engelmann in 1929,¹has been characterized by progressive osteosclerosis of the diaphyses of the long bones associated with neuromuscular abnormalities. An underdeveloped physical state with muscular weakness and a wide-based waddling gait has been a prominent and constant finding.^2,3Although muscle biopsies have been generally unrevealing,^4,5Singleton et al reported in 1956 the presence of atrophic muscle fibers with degenerative changes.⁶Central nervous system (CNS) findings have included varied tendon reflex responses, ankle clonus, optic atrophy, and nystagmus.^2,3,7,8Lennon, Schechter, and Hornabrook⁸in 1961 attributed some of these neurological changes to narrowed cranial nerve exit foramina of the skull. Additional skeletal abnormalities have included prominent and symptomatic lordosis, scoliosis, flat feet, and knock-kneed and bowlegged deformities.⁴ Roentgenograms of the long bones have revealed symmetrical diaphyseal sclerosis bilaterally with thickening of the periosteum and endosteum.