| An extremely rare, complex form of hereditary spastic paraplegia with characteristics of slowly progressive spastic paraplegia (with increased muscle tone, decreased strength in the anterior tibial muscles and hyperreflexia in the lower extremities with Babinski sign) presenting in adulthood, associated with Paget disease of the bone. Cognitive decline, dementia and myopathic changes at muscle biopsy have not been reported. Mutations in the VCP gene (9p13.3), encoding transitional endoplasmic reticulum ATPase, have been found to be causative for this disease. |