Evidence & Methods
Spinal fusion is a common procedure for a wide range of degenerative conditions. It is unclear whether outcome metrics primarily describing pain and pain-restricted function are adequate descriptors of outcome in this diverse group.
In a heterogeneous cohort of patients having cervical fusion for a degenerative process, the authors defined clinically important improvements in pain score, NDI, and the PCS (of the SF-36) by a post-hoc anchor-based method. Remarkably, less than half of the subjects reported any improvement in the post-hoc anchor: self-reported improvement in general health. MCID and SCB were calculated for various metrics using this anchor and appeared somewhat small. External metrics (eg, pain medication, health care utilization, occupational status) were not evaluated.
The authors' method does not appear to persuasively describe “good outcomes” in this setting. Unlike fusion in the lumbar spine, where pain is nearly always a central presenting feature, many cervical procedures are done to prevent or correct neurologic injury or deformity, independent of pain considerations. In addition, a patient's perception of “general health” after these procedures may also be independent of changes in neck discomfort. Separate analyses of specific conditions or rationale for surgery may show better validity for the post-hoc anchor-based calculations than this analysis by operation-type.
– The Editors