Purpose of the study: Surgery for lumbar canal stenosis is classically an intracanalar procedure with the risk of injury of the dura mater or nerve roots or of postoperative haematoma with secondary sequelae. Extracanalar surgery could be useful for the treatment of lumbar canal stenosis in older patients.

Material and methods: The Farcy procedure is based on the observation that the root is compressed in the recessus by the tip of the upper facet. The foramen is too small. The tip can be cut with a chisel along a horizontal line plumb with the pedicle landmark on the upper border of the lateral mass. The tip of the facet and its osteophyte can be removed laterally to medially with a curette and separated from the capsule and the yellow ligament without exposing the root. Release of the foramen is verified with an elevator. From August 1999 to July 2000, 15 patients (ten women and five men) underwent the Farcy procedure in association with fusion-osteosynthesis. Mean age was 60.4 years (55–71). The patients had suffered a mean 8.5 years (1–30). All had lumbalgia. Radiculalgia involved one root in seven patients, two in four and three in four. The Beaujon score was 6.73 (0–14) before surgery. The procedure was performed at one level in five patients, at two in four, at three in four and at four in two. Laminectomy was associated in two patients early in our experience.

Results: Postoperative Beaujon score was 15.2 (9–12) with cure of lumbalgia in eleven patients and cure of radiculalgia in ten patients. five patients had a 100% relative gain and only four had a gain of less than 50%. There were two failures explained by a history of stroke in two women (67 and 71 years). The only complications were one haematoma that was reoperated and one superficial infection.

Discussion: These results are comparable with those obtained with intracanalar surgery. The procedure is equally effective and is more rapid without the risk of the classical complications. The one extradural haematoma observed was related to laminectomy which later was noted to be unnecessary.

Conclusion: The Farcy procedure is a useful technique for the treatment of lumbar spine stenosis. Further experience is needed to determine whether this extracanalar technique should replace classical techniques with the risk of complications related to exposure of the canal.