The subacromial area lies between the top of the arm bone (humerus) and a bony prominence on the shoulder blade (acromion). The coraco acromial ligament completes the arch.
A muscle and fluid filled cushion (bursa) lie between the arm bone and acromion. With certain movements and positions these structures can become pinched and inflamed. The pain that you have been experiencing is caused by this pinching and is typically felt on movements such as reaching and putting your arm into a jacket sleeve.
The Acromio-clavicular Joint is a small joint formed between the summit of the shoulder blade (acromion) and the collar-bone (clavicle).This joint can be a frequent source of pain in the shoulder region, especially while performing movements at or above the level of the shoulder. Moving ones arm across the chest at shoulder level, to touch the opposite shoulder can produce significant discomfort if this joint is affected.
Sometimes a calcific deposit (Calcifying tendonitis) is found in the tendons and this may be the cause of the symptoms.
Usually physiotherapy is the mainstay in the management, surgery is indicated if conservative management fails.
The operation is done arthroscopically usually through two or three 5mm puncture wounds. It involves cutting the ligament and shaving away part of the acromion bone. This increases the space of the subacromial area and reduces the pressure on the muscle and bursa allowing them to heal.
The operation aims to increase the size of the subacromial area and reduce the pressure on the muscle. This allows the muscle to heal.
Pain may arise as well from the small joint between the shoulder blade and the collar bone (Acromio-clavicular joint (AC joint)) due to a cartilage tear or arthritis with wear & tear. In these cases resection arthroplasty of the AC joint [removal of few millimeters of bone from each side of this joint is performed].
If a calcific deposit will be found in the tendons, this will be excised to allow the tendons to heal.