Vitamin C with its antioxidant role has many indications. The objective of this study is to demonstrate that taking vitamin C as a preventive significantly reduces the occurrence of complex regional pain syndrome (CRPS) type 1 in the aftermath of a scheduled surgery of the upper limb.

The preventive role of vitamin C on the development of CRPS type 1 was already demonstrated in traumatology and foot surgery.

The management of CRPS type 1 is long and expensive. A preventive care seems beneficial. Some studies already performed suggest a similar role in scheduled surgery of the upper limb, major provider of CRPS type 1.The aim of the study is to demonstrate a significant reduction of CRPS 1 when taking vitamin C during the perioperative period in upper limb surgery. It is a prospective, randomized, double-blind, with placebo use, in two parallel group, multicenter and national. Patients are followed by their surgeon, under the terms of monitoring their disease. Two visits are required: one at 6 months and at 12 months. The patients will be reviewed at least in the two consultations looking for CRPS type 1 according to the criteria of the International Association for the Study of Pain (IASP)

Inclusion Criteria:

• patients over 18 yo
• patients undergoing major surgery of the upper limb
• patients able to give their consent to follow the protocol of treatment and monitoring.

Exclusion Criteria:

• children,
• patients under guardianship,
• pregnant or lactating women,
• patients with hemochromatosis,
• allergy or known hypersensitivity to one of the molecules of treatment,
• patients suffering or having already suffered from complex regional pain syndrome type 1 or type 2,
• patients unable due to personal or professional mobility, to conduct post-operative follow up,
• patients undergoing surgery with nerve suture with nerve graft, emergency surgery,
• patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency,
• patients with chronic kidney disease