Complications and Outcomes After Three-Column Osteotomy: A 5-Year Follow-up.

BACKGROUND: Three-column spinal osteotomies (3-CO) are powerful techniques used to correct spinal deformity. These surgeries are associated with an elevated risk of complications. While outcomes have been reported in the literature with 2 years follow-up, longer-term outcomes of three-column osteotomies remain understudied.

OBJECTIVES: This study aims to examine patient reported outcomes and complications for three-column osteotomies at 5 years.

STUDY DESIGN: Retrospective review of a prospectively collected spinal deformity cases database.

PATIENT SAMPLE: All consecutive adult patients at a single spine surgery center treated with either a pedicle subtraction osteotomy (PSO) or vertebral column resection (VCR) for spinal deformity, and with a minimum 5-year follow-up were included.

OUTCOME MEASURES: Visual-analog scale (VAS) for back pain score [0 to 10], Oswestry Disability Index (ODI) score [0 to 100], number of complications, revision rate, sagittal balance, lumbar lordosis at preoperative and at 5-year visit.

METHODS: Data was extracted from a prospectively collected spinal deformity surgery database continuously updated since 2002 with data from operative reports, patients' medical visit notes and patients' self-reported VAS and ODI questionnaires completed at each office visit. Radiographic measurements were performed on standing full-length spine radiographs taken at pre-op and 5Yr visits. Descriptive statistics, comparison of means and proportions among groups, and a logistic regression analysis were conducted using the statistical software package SPSS version 28. Statistical significance was set at p <0.05.

RESULTS: 127 consecutive adult patients with minimum of 5-year follow-up undergoing a 3-CO posterior spinal surgery for spinal deformity were identified and included in the study, 79 (62%) were treated with PSO, and 48 (38%) with VCR. Both PSO and VCR groups demonstrated significant improvements in VAS (PSO pre-op: 6.7, 5Yr: 4.6, p<0.001; VCR pre-op: 7.1, 5Yr: 5.2, p<0.001), and ODI (PSO pre-op: 52.9, 5Yr: 45.4, p<0.001; VCR pre-op: 57.5, 5Yr 43.0, p<0.001) that were maintained at 5 years. Major and minor complications occurring within 5 years were not statistically different between the PSO and VCR groups (major: 59.5% vs 56.3%, p=0.85; minor: 45.6% vs 37.5%, p=0.46). The rate of revision surgery within 5 years was 39.4% overall. Of the fifty patients requiring revision, 37.5% were for nonunion, 27.1% instrumentation failure, 14.6% proximal junctional kyphosis (PJK), 12.5% vertebral fracture, 6.3% motor weakness, and 2.1% infection. Improvements in lumbar lordosis were maintained at 5 years in both the PSO (29.9° vs 47.2°, p<0.001) and VCR (34.6° vs 48.5°, p<0.001) groups while sagittal balance maintained significant improvement in the VCR group (9.5 cm vs 6.3 cm, p=0.008) but not the PSO (11.4 cm vs 9.3 cm, p=0.065).

CONCLUSION: Patients undergoing three-column osteotomies had a major complication rate of 57.5% and a minor complication rate of 42.5% after 5 years. Improvements in lumbar lordosis were maintained at 5-year follow-up, but sagittal balance was only maintained in the VCR group. Despite these radiographic findings, both VCR and PSO groups maintained significant clinical improvements in both VAS and ODI scores at 5-year follow up.