Long-Term Outcomes After Minimally Invasive Bilateral or Unilateral Laminotomy for Degenerative Lumbar Spinal Stenosis: A Minimum 10-Year Follow-Up Study

OBJECTIVE: The optimal surgical procedure for minimal surgical intervention in symptomatic degenerative lumbar spinal stenosis (DLSS) is unknown. This article presents a method of minimally invasive decompression alone and reports the long-term outcomes and complications of patients treated with minimally invasive bilateral or unilateral laminotomy decompression performed by one surgeon. METHODS: Patients with DLSS who underwent minimally invasive laminotomy decompression alone from March 2008 to October 2010 were included in the study, and 106 patients were followed up for at least 10 years. Clinical outcomes were assessed by Japanese Orthopedic Association, Oswestry Disability Index, and visual analog scale for back pain scores, and changes in walking tolerance and leg numbness were evaluated. Complications were recorded. RESULTS: A total of 106 patients who met the inclusion and exclusion criteria were included in the study (mean age = 64 years, range = 43-83). The Japanese Orthopedic Association, Oswestry Disability Index, and visual analog scale back pain scores of patients significantly changed between before surgery and at subsequent follow-up (P < 0.001). The walking tolerance and leg numbness of patients significantly improved (P < 0.001), and these functions were well maintained during follow-up. Complications included intraoperative dural tears (n = 5), a wound infection (n = 1), deep vein thrombosis (n = 1), and nerve root lesions on the asymptomatic side (n = 2), all of which recovered within 3 months. CONCLUSIONS: Minimally invasive laminotomy decompression is an effective procedure and achieves beneficial long-term clinical results for DLSS.