Outcome after less-invasive decompression of lumbar spinal stenosis: a randomized comparison of unilateral laminotomy, bilateral laminotomy, and laminectomy. - Thome,C.; Zevgaridis,D.; Leheta,O.; Bazner,H.; Pockler-Schoniger,C.; Wohrle,J.; Schmiedek,P. (J Neurosurg, 2005)