Acute postoperative aggravation of radiculopathy as a complication of free fat transplantation in lumbar disc surgery: case report.

This case report illustrates a rare case of motor weakness caused by a free fat graft herniation. A 40-year-old woman who had undergone surgery for a herniated lumbar intervertebral disc experienced right lower leg weakness. On magnetic resonance image (MRI) a herniated free fat graft was noted. An emergent operation was performed and the herniated fat graft was removed. Postoperatively, the patient recovered well with improvement of the motor weakness. MRI is a good method for diagnosis of fat graft herniation. The mechanisms of this complication have been documented, and the size of the fat graft plays an important role. The methods for prevention of this herniation are also discussed. Although the transplantation of adipose tissue has many advantages, including the prevention of postoperative epidural fibrosis, great care is needed when applying a fat graft intra-operatively. When a postoperative neurologic deficit develops, herniation of the fat graft must be considered. An emergent operation is the treatment of choice for this particular complication.