Failure of autologous fat grafts to prevent postoperative epidural fibrosis in surgery of the lumbar spine

In three cases of lumbar disc herniation, autologous fat grafts were inserted over the dura mater and the exposed nerve roots during surgery with the aim of preventing postoperative epidural fibrosis. A second operation had to be performed in two of these cases as a result of the radiographic appearance of excessive scar formation in the epidural and adjacent regions of the nerve root giving rise to symptoms. In the third patient, myelographic studies revealed the development of this type of hypertrophic scarring; however, the patient refused a further operation. The hypertrophic epidural scarring occurred in these three cases despite the presence of autologous fat grafts. Histopathological examination of the fat removed from the two patients who were operated on a second time showed a fibrotic infiltration into the fat graft.