Study design: A retrospective surgical case series was conducted using a condition-specific, patient-based outcomes assessment.
Objective: The goal of this study was to describe the outcome predictors of decompressive surgery for degenerative lumbar spinal stenosis (DLSS).
Summary of background data: Surgical decompression is the recommended treatment for patients with moderate to severe DLSS. Previous studies have reported that factors such as the number of operated levels and patient health status are predictors of surgical outcomes.
Methods: This study analyzed the success rates of 58 DLSS patients treated with decompressive surgery. Outcomes were measured with the Zurich Claudication Questionnaire (ZCQ) completed pre-operatively and at least 12 months post-operatively (range 12-54 months). The ZCQ includes three distinct domains that involve symptom severity, physical function, and patient satisfaction. Variables such as age, sex, pre-operative symptom severity, and arthrodesis were analyzed as predictors of success.
Results: The study group included 21 males and 37 females, and the mean age of all patients was 66 years (range 41-80 years). Overall, 63.8% of the patients had significant clinical improvement in Symptom Severity, 55.2% had significant clinical improvement in Physical Function, and 58.6% of the patients were at least somewhat satisfied; 63.8% (37/58) of the patients were considered to be clinically successful. Patients with more severe pre-operative symptoms and more physical function restrictions had better success results than those patients with milder symptoms and less restrictive physical function. Also, patients who were followed for less than 24 months had better success than those followed for more than 24 months. There was no significant difference in the clinical success rates of (1) patients who were fused and those not fused, (2) males and females, (3) patients aged less than 65 years and those greater than 65 years, and (4) patients who were treated at one or two levels and those treated at three or four levels.
Conclusion: The results of this retrospective study indicate that operative decompression of the lumbar spine offers significant improvement for patients with DLSS. Although not all comparisons were statistically significant, there was a trend for DLLS patients aged less than 65 years with more severe pre-operative symptoms and physical function disturbances treated at one or two levels with a laminectomy and fusion to have the best outcomes.