Study Design. Retrospective cohort analysis.
Objective. To compare early treatment failures, survivorship, and clinical outcomes of 3 procedures used to treat symptomatic lumbar spinal stenosis and degenerative deformity.
Summary of Background Data. Symptomatic lumbar stenosis is commonly seen in association with degenerative deformity, often leading to more complex surgical treatment, with laminectomy and fusion, supplanting laminectomy alone. More recently, the interspinous process spacer (ISP), developed to treat straightforward spinal stenosis, has been used in patients with spinal deformity to limit morbidity, although no studies have compared outcomes in this patient population.
Methods. A retrospective cohort analysis of 90 consecutive patients, mean age 70 years, with 5-year mean follow-up (minimum, 2 yr), treated for stenosis with associated deformity with ISP device placement, laminectomy alone, or laminectomy and short-segment fusion. Early failure was defined as return to the operating room for revision of the index level or adjacent segment within 2 years. A Kaplan-Meier survival analysis was performed, and clinical outcomes and patient satisfaction was assessed.
Results. Reoperation within 2 years was noted in 16.7% of patients treated for spinal stenosis and mild deformity. There was a significantly higher rate of same-level recurrence in the ISP group (33.3%), than the laminectomy (8.3%) and lami/fusion groups (0%) (P< 0.0001). Early reoperation due to adjacent segment pathology (ASP) was most common in the lami/fusion group (13.3%). Kaplan-Meier analysis revealed lowest survival for the ISP group and highest survival in the laminectomy-alone group at 2 years (P= 0.043) and 5 years (P= 0.007).
Conclusion. Early failure was significantly more common in patients treated with an ISP device for spinal stenosis and lumbar deformity, whereas reoperation due to symptomatic adjacent segment pathology was most common in patients treated with laminectomy and fusion. Laminectomy alone had the highest rate of survival.
Level of Evidence: 3