Surgical experience of 120 patients with lumbosacral lipomas

The surgical experience of 120 patients with lumbosacral lipomas is describ ed. 47 of 120 patients were preoperatively found to be neurologically intac t, the remaining 73 patients presented with various neurological signs incl uding reflex changes, sensory disturbances, muscle weakness and sphincter p roblems. Neuro-imagings allowed a classification of lumbosacral lipomas int o five types: (1) dorsal type; (2) caudal type; (3) combined type; (4) fila r type; and (5) lipomyelomeningocele. Although all 120 patients underwent u ntethering of the spinal cord, the nerve roots passing through the lipoma i tself and the neural tissues protruding externally to the spinal canal, res pectively, tended to prevent satisfactory surgical removal of the lipoma in combined type lipomas and lipomyelomeningoceles. During 8.96 years of a me an postoperative follow-up period, there was no significant deterioration i n most of the patients and some patients even improved in function. However , two patients with combined type lipomas developed neurological deteriorat ion just after surgery, and five (two dorsal, two caudal and one combined t ype lipomas) did in the fashion of a late-onset. There are two different pa tient groups of lumbosacral lipomas: one group (caudal and filar type lipom as, and most of dorsal type lipomas) in whom the surgical anatomy is simple and satisfactory untethering surgery could be done without risk, and anoth er (combined type lipomas and lipomyelomeningocele) in whom surgery would b e accompanied with some risk and sometimes complete untethering could not b e achieved because of the complicated anatomy of the lesion. Surgical diffi culty of the latter group can be correlated with the increased frequency of neurological deterioration occurring just after the operation, but not of delayed one. Concerning prophylactic surgery for asymptomatic patients, the former group of patients are obviously good candidates, but the latter gro up is not.