Object. When performing surgery, the extraforaminal window is very narrow at the L5—S1 level. The authors describe a microsurgical method for decompression of the L-5 nerve root trapped between a marginal osteophyte of the vertebral body and the transverse process. The procedure was performed in 16 patients with extraforaminal stenosis.
Methods. The cranial part of the L5—S1 facet joint and the caudal portion of the pedicle and transverse process of L-5 were removed via a midline skin incision and partial resection of the pars interarticularis; a high-speed drill was used as was a surgical microscope. The affected nerve root was decompressed and mobilized cranially.
Postoperatively all patients reported excellent relief of their sciatic pain, and there were no technique-associated complications. There was no recurrence during the follow-up period, that ranged from 14 to 70 months.
Conclusions. The authors recommend this technique for the effective decompression of symptomatic extraforaminal L5—S1 stenosis. The need for a dangerous and tedious removal of the vertebral osteophyte together with spinal fusion is avoided.