Efficacy of decompression and fixation for metastatic spinal cord compression: analysis of factors prognostic for survival and postoperative ambulation

Abstract

Objective: The goals of surgical intervention for metastatic spinal cord compression (MSCC) are prolonging survival and improving quality of life. Non-ambulatory paraplegic patients, either at presentation or after treatment, have a much shorter life expectancy than ambulatory patients. We therefore analyzed prognostic factors for survival and postoperative ambulation in patients surgically treated for MSCC.

Methods: We assessed 103 patients with surgically treated MSCC who presented with lower extremity weakness between January 2001 and December 2008. Factors prognostic for overall survival (OS) and postoperative ambulation, including surgical method, age, sex, primary tumor site, metastatic spinal site, surgical levels, Tokuhashi score, and treatment with chemo- or radiation therapy, were analyzed retrospectively.

Results: Median OS was significantly longer in the postoperatively ambulatory group [11.0 months; 95% confidence interval (CI), 9.29-12.71 months] than in the non-ambulatory group (5.0 months; 95% CI, 1.80-8.20 months) (p=0.035). When we compared median OS in patients with high (9-11) and low (0-8) Tokuhashi scores, they were significantly longer in the former (15.0 months; 95% CI, 9.29-20.71 months vs. 9.0 months; 95% CI, 7.48-10.52 months; p=0.003). Multivariate logistic regression analysis showed that preoperative ambulation with or without aid [odds ratio (OR) 5.35; 95% CI 1.57-18.17; p=0.007] and hip flexion power greater than grade III (OR 6.23; 95% CI, 1.29-7.35; p=0.038) were prognostic of postoperative ambulation.

Conclusion: We found that postoperative ambulation and preoperative high Tokuhashi score were significantly associated with longer patient survival. In addition, preoperative hip flexion power greater than grade III was critical for postoperative ambulation.

Keywords: Ambulation; Cord compression; Hip flexion; Prognostic factor; Spinal metastasis; Survival.

Fig. 1

Two different surgical methods are shown. The amount of anterior column removal is larger and anterior support is done in 360° group.

Fig. 2

This graph shows Kaplan-Meier overall survival curve of surgically treated MSCC patients. Table shows 10-month median survival. metastatic spinal cord compression (MSCC)

Fig. 3

These two graphs show Kaplan-Meier survival curves of post-operative ambulation group (blue colored graph) and non-ambulation group (green colored graph). Median survival of post-operative ambulation group is longer than that of non-ambulation group. Table of this figure shows 11-month and 5-month median survival in the post-operative ambulation group (blue colored character) and the non-ambulation group (green colored character). Log rank test also shows statistically significant difference between two groups (p=0.035).

Fig. 4

These two graphs show Kaplan-Meier survival curves of low Tokuhashi score group (blue colored graph) and high Tokuhashi score group (green colored graph). Median survival of low Tokuhashi score group is shorter than that of high Tokuhashi score group. Table of this figure shows 9-month and 15-month median survival in the low Tokuhashi score group (blue colored character) and the high Tokuhashi score group (green colored character). Log rank test also shows statistically significant difference between two groups (p=0.003).

Fig. 5

These two graphs show Kaplan-Meier survival curves of good prognosis group (blue colored graph) and poor prognosis group (green colored graph). Median survival of poor prognosis is shorter than that of good prognosis group. Table of this figure shows 12-month and 9-month median survival in the good prognosis group (blue colored character) and the poor prognosis group (green colored character). Log rank test also shows statistically significant difference between two groups (p=0.039).