A novel minimally invasive technique of inter-spinal distraction fusion surgery for single-level lumbar spinal stenosis in octogenarians: a retrospective cohort study

Objective Surgical treatment of lumbar spinal stenosis (LSS) in octogenarians (patients aged ≥ 80 years) has been a challenge. Inter-spinal distraction fusion (ISDF)—a minimally invasive procedure—was used for treating LSS in octogenarians. This retrospective cohort study aimed to investigate the clinical efficacy and safety of a minimally invasive ISDF technique for LSS in octogenarian patients. Methods From April 2015 to April 2019, octogenarian patients who underwent lumbar fusion surgery due to single-segment LSS were included. The patients were grouped into the ISDF group and posterior lumbar interbody fusion (PLIF) group based on the type of surgery. Clinical outcomes were evaluated using scores of the visual analog pain scale (VAS), Oswestry Disability Index (ODI), and Japanese Orthopedics Association (JOA) scale. Radiographs were assessed for the intervertebral angle (IA), lumbar lordosis (LL), and posterior disc height (PDH). After 2 years postoperatively, all patients underwent computed tomography (CT) to evaluate the fusion condition. Perioperative data and related complications were recorded. Results Sixty-two patients were included (mean age: 82.22 ± 1.95 years). The ISDF and the PLIF groups had 34 and 28 patients, respectively. The average follow-up time was 2.1 ± 0.25 years. There was no significant difference in VAS, ODI, JOA, and PDH scores between both groups preoperatively and at each postoperative time-point. The IA and LL showed significant differences between both groups after surgery ( p < 0.05). The postoperative IA in the ISDF group were significantly lower than the preoperative values, while that in the PLIF group were markedly increased. The PLIF group had an increased LL compared with that preoperatively ( p < 0.05), while the LL in the ISDF did not significantly change. The operative time, blood loss, hospital stay time, and the rate of perioperative complications of the ISDF group were significantly lower than those of the PLIF group ( p < 0.05). There was no significant difference in the fusion rates between both groups. Conclusion ISDF surgery is a viable method for octogenarian patients with LSS that provides a similar clinical efficacy, shorter operative time, less blood loss, shorter hospital stay time, and fewer complications, compared to the PLIF surgery.