Success and failure after surgery of degenerative disease of the lumbar spine: an operational definition based on satisfaction, pain, and disability from a prospective cohort

BACKGROUND: To describe success and failure (S&F) after lumbar spine surgery in terms equally understandable across the entire health ecosystem. METHODS: Back and leg pain and disability were prospectively recorded before and up to 12 months after the procedure. Satisfaction was recorded using a Likert scale. Initially, patients were classified as satisfied or unsatisfied. Optimal satisfaction/unsatisfaction cutoff values for disability and pain were estimated with ROC curves. Satisfied and unsatisfied groups underwent a second subdivision into four subcategories: success (satisfied AND pain and disability concordant with cutoff values), incomplete success (satisfied AND pain and disability nonconformant with cutoff values), incomplete failure (unsatisfied AND pain and disability nonconformant with cutoff values), and failure (unsatisfied AND pain and disability concordant with cutoff values). RESULTS: A total of 486 consecutive patients were recruited from 2019–2021. The mean values of preoperative PROMs were ODI 42.2 (+ 16.4), NPRS back 6.6 (+ 2.6) and NPRS leg 6.2 points (+ 2.9). Of the total, 80.7% were classified as satisfied, and 19.3% were classified as unsatisfactory. The optimal disability and pain cutoff values for satisfaction/unsatisfaction (NPRS = 6, AND ODI = 27) defined a subdivision: 59.6% were classified as success, 20.4% as incomplete success, 7.1% as incomplete failure and 12.4% as failure. The descriptions of each group were translated to the following: success—all patients were satisfied and presented no or only mild to tolerable pain and no or borderline disability; incomplete success – all patients were satisfied despite levels of pain and/or disability worse than ideal for success; incomplete failure – all patients were not satisfied despite levels of pain and/or disability better than expected for failure; failure – all patients were unsatisfied and presented moderate to severe pain and disability. CONCLUSION: It is possible to report S&F after surgery for DDL with precise and meaningful operational definitions focused on the experience of the patient.