['To evaluate the potential prognostic impact of the effect of radiotherapy (RT) on motor function and of the post-RT ambulatory status on survival in metastatic spinal cord compression (MSCC) patients.', 'Of 1,852 patients irradiated for MSCC, 778 patients (42%) received short-course RT and 1,074 (58%) received long-course RT. The effect of RT on motor function (improvement vs. no change vs. deterioration) and the ambulatory status after RT (ambulatory vs. nonambulatory) were evaluated with respect to survival.', 'The actuarial survival rate of the entire cohort was 56% at 6 months, 43% at 12 months, and 32% at 24 months. The patients in whom motor function improved after RT had a significantly better 1-year survival rate than those who had no change or deterioration of motor function (75% vs. 40% and 3%, p < 0.001). The 1-year survival rate of the patients who were ambulatory after RT was significantly better than for those who were not ambulatory (63% vs. 4%, p < 0.001). The results were confirmed in multivariate analysis.'] Is improved posttreatment functional outcome associated with better survival in patients irradiated for metastatic spinal cord compression?