Incidence of Iatrogenic Lumbar Spinal Instability after Laminectomy, Discectomy or Facetectomy

OBJECTIVE: This thesis aim to report the incidence of iatrogenic spinal instability that occurs after laminectomy, discectomy or facetectomy in Lumbar spine surgery. METHODS: This is a prospective study of 50 cases of degenerative lumbar spondylosis complaining of various symptoms of claudication, sciatica and back pain which were surgically managed by laminectomy according to the level of stenosis in the period between October 2018 and October 2020 in the neurosurgery department at Cairo university hospitals. Mesial facetectomy was added according to the degree of stenosis if needed. Some patients needed discectomy if sciatica was an eminent symptom. RESULTS: Out of 50 patients included: 9 patients (18%) developed postoperative instability. The number of levels operated on and the degree of mesial facetectomy were found to be variables that may affect postoperative stability. CONCLUSION: Iatrogenic instability may result from large laminectomy and extensive facetectomy for lumbar stenosis in patients who do not have obvious pre-existing instability. Key words: Iatrogenic spinal instability - Laminectomy - conventional open discectomy - Mesial facetectomy.