Effects of Mecobalamin on the Prevention of Complex Regional Pain Syndrome Type 1 Following Foot Ankle Surgery: A Randomized, Double-Blinded, Placebo-Controlled Trial.

Abstract

Mecobalamin has been proposed to improve the outcomes of Foot and Ankle patients with complex regional pain syndrome type 1 (CRPS-1). The primary outcome was to evaluate the effects of mecobalamin on the event rate of CRPS-1 after foot ankle surgery. The secondary outcomes were to compare the visual analog scale (VAS) and functional outcomes of both groups. The study recruited 440 patients. Operative foot and ankle patients were randomized into control (220 patients) and Mecobalamin groups (220 patients). Patients were assessed for CRPS-1 using the Budapest criteria for a follow-up period of 12 months. Preoperative and postoperative foot and ankle ability measure, Short Form 36, and VAS were compared. Analysis included 432 patients. CRPS-1 occurred in 4 patients (1.8%) in the mecobalamin group compared with 20 patients (9.3%) in the placebo group. After adjustment using multivariable regression, mecobalamin was associated with a significantly lower risk of CRPS-1, with the risk difference of -8.1% (95% confidence interval: -12.4 to -3.8; p < 0.001) compared with placebo. Postoperative pain and functional outcomes also favored mecobalamin. The reduction in VAS score from preoperation to postoperation was significantly greater in the mecobalamin group, with an adjusted mean difference of -0.49 (95% confidence interval: -0.8 to -0.2; p = 0.001) at the 1-year follow-up. Prophylactic mecobalamin significantly lowered the occurrence of CRPS-1 in foot ankle surgery. Level I. See Instructions for Authors for a complete description of levels of evidence.