Arthroscopic Capsular Release (ACR) is a minimally invasive keyhole (arthroscopic) procedure which has excellent success rates (90%) in alleviating pain and improving range of movment in patients suffering from frozen shoulder. The procedure is performed under a general anaesthetic and an anaesthetic injection (interscalene block) to numb the nerves in the arm so you should wake up feeling no pain. Two very small incisions (less than 1cm) are used, one at the back of the shoulder and one at the front, to perform the procedure. A camera is inserted into the joint and the diagnosis of frozen shoulder can then be confirmed and any another abnormality in the shoulder excluded. A radio frequency probe instrument is inserted into the joint via the other incision and this is used to release all the thickened scar tissue causing the frozen shoulder. As the procedure is performed under direct vision with a camera inside the joint no damage is caused to any of the normal structures within the shoulder joint which can happen with a manipulation under anaesthetic. As with any operation there is a very small risk of infection (less than 1%) or reaction to the general anaesthetic. Overall the operation is 90% successful in restoring good movement and pain relief to the shoulder. However 10% of patients find their shoulder ‘refreezes’ after a few weeks and further treatment may then be necessary including possibly further surgery.
A combination of steroid and local anaesthetic is injected into the shoulder joint at the end of the arthroscopic release. Only 2 stitches are needed to close the very small incisions.
When the patient wakes up from surgery the arm will be in a sling and this is worn for approximately 2 days until the arm feels normal and the anaesthetic block numbing the arm has resolved. Patients are encouraged to move the shoulder as much as possible and as soon as possible in combination with supervised physiotherapy. This is very important to prevent the shoulder stiffening up again and preserve the increased range of movement gained by performing the arthroscopic release. At surgery a full range of movement is usually obtained in the shoulder. After surgery some of this movement is lost initially as the muscles which move the shoulder (rotator cuff) which have become ‘tight’ in the months since the frozen shoulder started, will still be ‘tight’ and this is where the supervised physiotherapy exercises are critical to ‘stretching out’ these tight muscles. . The 2 sutures used to close the very small incisions are removed after 2 weeks and the incisions will not be very noticeable.
Generally by 6 weeks post operatively about 80-90% of most normal shoulder movements will have been achieved although recovery of internal rotation (hand behind the back) is much slower and takes a number of months. In about 20% of patients a second injection of steroid is needed at about 6 weeks as they feel the pain is getting worse again and generally this second injection then resolves the pain permanently.
Patient's can return to driving within approximately 10-14 days, light work (office based) by 2-3 weeks and manual activities by 6 weeks.