Long-term outcomes of revision fusion for lumbar pseudarthrosis: clinical article

Abstract

Object: The number of low-back fusion procedures for the treatment of spine disorders has increased steadily over the past 10 years. Lumbar pseudarthrosis is a potential complication of lumbar arthrodesis and can be associated with significant pain and disability. The aim of this study was to assess, using validated patient-reported outcomes measures, the long-term effectiveness of revision arthrodesis in the treatment of symptomatic pseudarthrosis.

Methods: This is a retrospective study of 47 patients who underwent revision lumbar arthrodesis for pseudarthrosis-associated back pain. Baseline 2-year outcomes were assessed using the following: visual analog scale (VAS) for back pain, Oswestry Disability Index (ODI), Zung Self-Rating Depression Scale, time to narcotic independence, time to return to work, EuroQol health-state utility, and physical and mental quality of life (Short Form [SF]-12 Physical and Mental Component Summary scores).

Results: The mean duration of time between prior fusion and development of symptomatic pseudarthrosis was 2.69 years. Bone morphogenetic protein was used in 4 cases (8.5%) of revision arthrodesis. A significant improvement in VAS back pain (7.31 ± 0.81 vs 5.06 ± 2.64, p = 0.001), ODI (29.74 ± 5.35 vs 25.42 ± 6.0, p = 0.001), and physical health SF-12 (23.83 ± 6.89 vs 27.85 ± 8.90, p = 0.001) scores was observed when comparing baseline and 2-year post-revision arthrodesis scores, respectively, with a mean cumulative 2-year gain of 0.35 quality-adjusted life years. The median time to narcotics independence was 12.16 (interquartile range 1.5-24.0) months and the median time to return to work was 4 months (interquartile range 3-5 months). By 2 years after revision surgery, no patients had experienced pseudarthrosis. The SF-12 Mental Component Summary (44.72 ± 7.90 vs 43.46 ± 7.51, p = 0.43) and Zung Self-Rating Depression Scale scores (39.36 ± 7.48 vs 41.39 ± 10.72, p = 0.37) were not significantly improved by 2 years.

Conclusions: The authors' study suggests that revision lumbar arthrodesis for symptomatic pseudarthrosis provides improvement in low-back pain, disability, and quality of life. Revision lumbar arthrodesis should be considered a viable treatment option for patients with pseudarthrosis-related back pain. Mental health symptoms from pseudarthrosis-associated back pain may be more refractory to revision surgery.