Revision Spinal Fusion in Patients Older than 75: Is it Worth the Risks?

2012

Summary

38 patients >75 years undergoing revision spinal fusion were compared with 54 age-matched patients undergoing primary fusion. Although both groups demonstrated similar and significant improvement at 1 year post-op, revision patients did substantially worse at 2 years while having more complications.

Introduction

The benefits of spinal fusion in patients older than 65 is well-documented. However, the clinical benefit to patients older than 75 of revision surgery, which often yields worse outcomes with higher complication rates, is uncertain.

Methods

92 consecutive patients > 75 with minimum 2 year follow-up underwent spinal fusion as either a primary (n=54) or revision (n=38) operation. Diagnoses were spondylolisthesis (n=39), scoliosis (n=26), and other degenerative spinal disorders (n=27). Outcomes were obtained prospectively by visual-analog pain scale (VAS) and Oswestry Disability Index (ODI) at pre-op, 1 year, 2 year, and latest follow-up.

Results

Revision patients had significantly worse scores compared with primary patients at all-time intervals, for both VAS (pre-op: 6.6 vs 5.6, 1 year: 3.6 vs 2.2, 2 year: 4.7 vs 2.4) and ODI (pre-op: 52.0 vs 44.3, 1 year: 36.4 vs 24.6, 2 year: 48.2 vs 24.3). Both groups improved significantly at 1 year post-op. At 2 years, the results of revision surgery deteriorated (VAS: -1.9, ODI: -3.8) while the benefits of primary procedures were maintained (VAS: -3.2, ODI: -20.0). Complications were greater in the revision group and included revision surgery (8 [21.1%] vs 6 [11.1%]), non-union (2 [5.3%] vs 2 [3.7%]), adjacent level fracture (5 [13.2%] vs 3 [5.6%]), infection (5 [13.2%] vs 3 [5.3%]), foot drop (1 [2.6%] vs 3 [5.3%]), imbalance (3 [7.9%] vs 1 [1.8%]), pulmonary failure (1 [2.6%] vs 1 [1.7%]), and death (1 [2.6%] vs 2 [3.6%]).

Conclusions

Despite having worse initial ODI and VAS scores, revision patients >75 years initially benefit as much as patients >75 undergoing primary operations. However, at 2 years revision patients do not have a sustained benefit despite a higher complication rate. While spinal fusion can be beneficial in elderly patients, revision surgery has an unfavorable risk to benefit profile.