People who have rotator cuff tears may have shoulder pain and weakness, with reduced shoulder function, leading to a reduced quality of life. Rotator cuff tears can be caused by an injury or can develop gradually. They can be minor or severe depending on the degree of damage to the tendons. Minor tears to the rotator cuff are very common and may not cause any symptoms at all. Diagnosis is usually by ultrasound or MRI.
Conservative treatment may include physical therapy, pharmacological treatments (including pain relief, and topical or oral non-steroidal anti-inflammatory medicines) and corticosteroid injections. If the tear is severe or has not responded to other treatments, surgical interventions such as debridement, rotator cuff repair, subacromial smoothing, tendon transfer or shoulder arthroplasty may be needed.
Inserting a biodegradable subacromial spacer aims to improve pain and restore shoulder function in people who have irreparable rotator cuff tears. The aim is to reduce subacromial friction by lowering the humeral head during shoulder abduction. It is a less invasive and potentially safer alternative to reverse shoulder arthroplasty or tendon transfer, and has shorter procedure and rehabilitation times.
The procedure is done under general or regional anaesthesia. The subacromial space is visualised using either arthroscopy or mini-open surgery. The damaged area is surgically cleared. Measurements are taken to determine the size of biodegradable spacer needed. The balloon-like spacer is then inserted into the subacromial space and inflated with saline solution. Once a sufficient volume is reached, the balloon is sealed and left in place. The balloon spacer is made from a biodegradable polymer and resorbs over about 1 year.