Walking speed is associated with postoperative pain catastrophizing in patients with lumbar spinal stenosis: a prospective observational study

BACKGROUND: The purpose of this study was to investigate whether walking speed is associated with postoperative pain catastrophizing in patients with lumbar spinal stenosis. METHODS: In this prospective observational study, consecutive patients with clinically and radiologically defined lumbar spinal stenosis underwent surgical treatment (decompression, or posterolateral or transforaminal lumbar interbody fusion) at Tottori University Hospital, between October 2015 and April 2018. The pain catastrophizing scale, walking speed, leg and back pain (numerical rating scale), and Japanese Orthopaedic Association score were evaluated preoperatively and at 3, 6, and 12 months postoperatively. Correlations between the pain catastrophizing scale and each variable were analyzed at each evaluation time point. The effect of walking speed on the pain catastrophizing scale was analyzed using mixed-effect models for repeated measurements. RESULTS: Ninety-four patients were included at baseline, and 83, 88, and 82 patients were analyzed at 3, 6, and 12 months postoperatively, respectively. The pain catastrophizing scale was significantly correlated with walking speed, leg pain, back pain, and the Japanese Orthopaedic Association score at all evaluation time points. The pain catastrophizing scale was associated with walking speed at all evaluation time points. CONCLUSIONS: Our results suggest that changes in postoperative pain catastrophizing after lumbar spine surgery are associated with walking speed. Thus, walking speed is a necessary assessment for the management of pain catastrophizing and associated pain and disability in patients after lumbar spine surgery.