Effects of Mecobalamin on the Functional Outcomes of Complex Regional Pain Syndrome Type 1 of the Foot and Ankle

Because of the unclear pathophysiology and the lack of consensus on the gold standard treatment of complex regional pain syndrome (CRPS), management requires a multidisciplinary approach, with the use of various treatment modalities. Nonetheless, no studies have ever been conducted to uncover the potential of mecobalamin as a treatment for CRPS type 1. Hence, the aim of this clinical trial was to evaluate the effects of mecobalamin on the functional outcomes of patients with CRPS type 1 of the foot and ankle, the total amount of pregabalin ingested, and the duration of pregabalin use in each patient.

Forty-seven patients diagnosed with acute CRPS type 1 of the foot and ankle were recruited. Patients were randomly allocated into a control group (23 patients) and a mecobalamin group (24 patients), both receiving similar pain control medications and rehabilitation programs. Three divided doses of mecobalamin 1.5 mg/d were provided to the mecobalamin group for the first 3 months, whereas a placebo was administered to the control group. Data were collected from the pretreatment period, and from 1, 3, 6, and 12 months following the treatment.

Both groups had similar demographics. The mean Foot and Ankle Ability Measure (FAAM) activities of daily living (ADL) and FAAM-sport scores in the mecobalamin group at 3 months were 74.5 ± 17.9 and 56.3 ± 22.9, whereas the mean FAAM-ADL and FAAM-sport scores in the placebo group at 3 months were 62.2.5 ± 15.2 and 43.4 ± 14.9, respectively (P < .05). The 36-Item Short Form Health Survey (SF-36) mental health subscale after 3 months were 83.3 ± 9.5 points and 75.8 ± 12.6 points in the mecobalamin and placebo group, respectively (P < .05). However, at other time points of assessment (1, 6, and 12 months), the improvement in symptoms was not distinguishable between the 2 groups. Both the amount and duration of total pregabalin required to achieve similar improvements in pain scores were significantly lower in the mecobalamin group than the control group.

This small study revealed an improvement of the functional outcomes in patients with CRPS type 1 of the foot and ankle who received mecobalamin instead of a placebo at 3 months that was not sustained at 6 and 12 months. We identified an average 39% total reduction in the amount of total pregabalin used in the mecobalamin group in the first 12 months.