Effectiveness of an Oxygen-nitrous Oxide Mixture During Physical Therapy for Frozen Shoulder

Inclusion Criteria: * Affiliated with a social security system * Has signed the consent form * Patient has a painful, or initially painful but stable frozen shoulder (adhesive capsulitis): stiffening characterized by a passive loss of amplitude on three planes. This loss of amplitude is greater than or equal to 50% of controlateral amplitude when the controlateral shoulder is considered as normal. Otherwise, the loss of amplitude is greater than or equal to 50% of normal anatomical values. * Radiography confirms the integrity of the glenohumeral interspace. Exclusion Criteria: * Intercurrent, evolving or unstable pathology: cancer, advanced cardio-vascular pathology, severe infection * The patient is taking a treatment that may interfere with the study (eg corticoids, pain killers, chemotherapy) * Contra-indication for physical therapy * Coagulopathy * Advanced diabetes mellitus, with neurological or joint complications * Contra indication for the experimental treatment * Pregnant or nursing women * Patient's mental state prevents him/her from understanding the nature of the study, its objectives and potential consequences. * Patient under guardianship * Patient is in an exclusion period determined by a previous study * Patient not able to follow protocol constraints or timetable * Medical history of local infection, polyarthritis or neuropathy that might explain the shoulder pain. * Absence of radiculopathy of cervical origin, of rotator cuff tears or evolving shoulder te…