This is a double-blind interventional superiority study evaluating the efficacy of suprascapular nerve block in addition to conventional therapies for adhesive capsulitis. Adhesive capsulitis is a pathology that results in reduced shoulder mobility due to retraction of the periarticular capsule. It may be primary or secondary to traumatic or neurological events, or associated with diabetes in particular. The usual treatment includes re-education sessions to improve joint amplitude and restore shoulder mobility. In persistent forms, intra-articular injection of cortisone is combined with distension of the capsule with a local anaesthetic under radiographic control. In some countries, subscapular nerve block (reversible anaesthesia) is used to improve pain. The combination of arthrodistension and subscapular nerve block has never been performed to accelerate the healing process. The aim of this study is to compare the performance of these two procedures together against the reference technique alone on time to improvement with the number of patients improved at one month according to the Constant score. This score is used to assess shoulder pain and function, with a significant improvement above eight points.