Autosomal recessive osteopetrosis with Arnold Chiari malformation type 1 and syringomyelia

Osteopetrosis is a rare genetic disorder with decreased bone resorption due to osteoclast failure. This leads to a generalized increase in bone density and abnormal bone remodeling. Neurological manifestations can occur due to intracranial restriction of growth of foramina. We present the case of a 23-year-old man with autosomal recessive osteopetrosis who presented with right sided upper motor neuron signs. Magnetic imaging resonance demonstrated a Chiari I malformation with an extensive syrinx extending from the cervicomedullary junction to the level of T12/L1 disc space.