New imaging characteristics for predicting postoperative neurologic status in patients with metastatic epidural spinal cord compression. A retrospective analysis of 81 cases

BACKGROUND CONTEXT: Several clinical features have been proposed for the prediction of postoperative functional outcome in patients with metastatic epidural spinal cord compression (MESCC). However, few articles address the relationship between preoperative imaging characteristics and the postoperative neurologic status. PURPOSE: This study aims to analyze the postoperative functional outcome and to identify new imaging parameters for predicting postoperative neurologic status in patients with MESCC. STUDY DESIGN: This study is a retrospective consecutive case series of patients with MESCC who were treated surgically. PATIENT SAMPLE: We assessed 81 consecutive patients who were treated with decompressive surgery for MESCC between 2013 and 2015. OUTCOME MEASURES: Eight imaging characteristics were analyzed for postoperative motor status by logistic regression models. Neurologic function was assessed using the Frankel grade preoperatively and postoperatively. METHODS: The following imaging characteristics were assessed for postoperative motor status: location of lesions in the spine, lamina involvement, retropulsion of the posterior wall, number of vertebrae involved, pedicle involvement, fracture of any involved vertebrae, T2 signal of the spinal cord at the compression site, and circumferential angle of spinal cord compression (CASCC). RESULTS: The postoperative neurologic outcome was better than the preoperative neurologic status (p<.01). In the entire group, 40.7% of the patients were non-ambulatory before the surgical procedure, whereas 77.8% of the patients could walk after surgery (p=.01). In the multivariate analysis, the location of the lesions (odds ratio [OR]: 3.89, 95% confidence interval [CI]: 1.19-12.77, p=.02) and CASCC (OR: 2.31, 95% CI: 1.44-3.71, p<.01) were significantly associated with postoperative neurologic outcome. A CASCC of more than 180° was associated with an increased OR that approached significance, and the larger the CASCC, the higher the risk of poor postoperative neurologic status. CONCLUSIONS: The postoperative neurologic status was dependent on the location of spine lesions and the CASCC. Patients with upper thoracic or cervicothoracic junction spine metastases or CASCC over 180° were at higher risk of relatively poor postoperative neurologic outcome. Timely, adequate surgical decompression is urgently warranted in these patients.