Interlaminar Endoscopic Treatment of Adjacent Segment Disease After Posterior Instrumented Lumbar Fusion

This study aimed to investigate the feasibility of interlaminar endoscopic surgery for the treatment of adjacent segment disease (ASD) after posterior instrumented lumbar fusion.

Between January 2019 and March 2023, the data of 22 patients with ASD who underwent revision interlaminar technique (R-ILT) endoscopic surgery after posterior instrumented lumbar fusion were retrospectively analyzed. For comparison, the data of 30 patients with single segment lumbar spinal stenosis who underwent primary interlaminar technique (P-ILT) endoscopic surgery were collected. The patient demographics and perioperative indicators were recorded and the clinical outcomes were analyzed with relevant evaluation scales. The surgical satisfaction was assessed using the modified MacNab criteria, lumbar stability was evaluated using the change in dynamic position radiographs of the spine at the final follow-up.

There were no statistical differences in patient demographics. The operation time, blood loss, fluoroscopy time, and the incidence of dural sac tears were higher in R-ILT group (p < 0.05). Both groups had significant relief in their lower back and leg pain symptoms, but the relief of the low back pain in R-ILT group was not as good as that in P-ILT group. Regarding recovery of lower limb function, the results of both groups were similar, according to the modified MacNab criteria, the good-to-excellent rate was 81.82% in R-ILT group and 86.66% in P-ILT group. The change in dynamic position X-ray of the spine proved that ILT would not destroy the stability of the spine.

Interlaminar endoscopic surgery is a feasible option for treating ASD. However, due to the impact of the initial operation, the difficulty and risk of reoperation have increased; therefore, surgical indications must be strictly controlled, and superb surgical skills are required.