hydrodilatation hydrodilatation hydrodilatation or hydraulic arthrographic capsular distension or distension arthrography is a medical treatment for adhesive capsulitis of shoulder. the treatment is applied by a radiologist assisted by a radiographer. contrast medium, a local anaesthetic and cortisone are injected into the joint. then up to 40ml of sterile saline solution are injected, using x-ray as guidance, to stretch the joint capsule. risk of complications is low. whether the treatment is successful is known after a couple of weeks. hydrodilatationother namesdistension arthrography the procedure is performed under imaging guidance, using either fluoroscopy, ultrasound or computed tomography (ct). hydrodilatation is felt to provide benefit via two mechanisms: manual stretching of the capsule and thus disruption of adhesions which are characteristic of adhesive capsulitis, and; the introduction of cortisone provides a potent anti-inflammatory effect and thus prevents further adhesion recurrence. research in 2008 has questioned the benefit of hydrodilatation as giving no statistical benefit over injecting cortisone alone.