Types (terms used)

Instability of the shoulder may be categorized by:

How patients present:

Surgical options:

I will not outline the conservative rehabilitation program which is usually undertaken before resorting to surgery for the recurrent subluxations and dynamic impingement as it outside the purpose of this project, but further details may be obtained from the Clinic.

There are 3 approaches to surgically stabilize the shoulder joint

1. Open surgery - newer approaches have allowed faster rehabilitation
2. Arthroscopic reattachment of the ligaments - minimal invasion, less scarring
3. Laser shortening of capsule and ligaments - from within, even less traumatic
4. Combination of 2. and 3.

1. Open surgery

This has been very reliable over the years to repair the ligaments back to the bone of the glenoid (cup) and in most cases the ligaments are shortened at the same time. The capsular repair (capsulorrhaphy) is associated with a 3 cm incision often placed in the axilla so that it is not greatly visible or larger incision on the front of the shoulder.

The main muscle on the front of the shoulder (subscapularis) is split between its fibres to expose the capsule which is cut in a "T" fashion and sewn up by overlapping the 2 flaps created, thus shortening and reinforcing the anterior capsule (ligaments). The labrum which connects the ligaments to the bone is reattached with bone anchors while the capsule is open. Previously surgeons would transect or cut the subscapularis muscle-tendon and this would need to be repaired with stitches and slow down the rehabilitation until sufficient strength returned to the repaired muscle, but by not cutting the muscle and only splitting it, earlier movement and exercises can be commenced.

Postoperative

• The patient can usually be discharged the day after surgery with oral analgesics.
• A sling is worn for 3 weeks, day and night, but may be removed for showers. The hand is left free to use while in the sling and driving is not permitted until the sling is removed.
• Appointment at 3 weeks for review of wound and begin physio for exercise program, strengthening rotator muscles and regaining range of motion.
• No stress in the overhead position for 3 months, when may consider racquet and non contact sports. At 6 months consider contact and throwing sports, but not full pitching which may take up to 18 months to regain full speed.

2. Arthroscopic Stabilization

The ligaments can be reattached to the bony cup (glenoid) through the arthroscope without a large skin incision and without cutting the muscles or capsule of the shoulder joint.

The first part of the operation is to examine all parts of the joint to remove any loose fragments, assess the direction of instability and the amount of capsular laxity (stretching of ligaments), and view the area of detached labrum. The bone is roughened so that the ligaments will stick back firmly and then a bone anchor is placed in the bone edge, a thread from the anchor is passed through the torn ligament or labrum and as it is tensioned, the ligaments are firmly applied to the bleeding surface of bone securely, thus reattaching the joint's restraining ligaments. More than one anchor is usually needed.

Some papers suggest that there is a higher rate of recurrences after arthroscopic repairs than after open repairs. This may be due to the loss of protective pain in the early postoperative period, which may allow stretching of the healing tissue before it is strong. More likely the ligaments are stretched as well as detached at the time of injury and this method reattaches these stretched ligaments, if they are cut and shortened then this is a single "all or none" step and may not be accurate or variable. With the simultaneous use of the LASER the ligaments, once attached, can be shortened in addition, until the required shortening is achieved (see below).
With the open surgery, the ligaments and muscles may be over tightened and lead to some loss of motion and later arthritis due to increased tension on the joint surfaces (cartilage).

Postoperative

• Much the same as for the open repair but because no skin or muscle dissection the pain is much less so;
• Discharge may be on the same day
• Sling to prevent undue use or movement for 3 weeks, but gentle movements encouraged, showering normally. No driving for 3 weeks.
• Strengthening at 3 weeks and full range of movements at 6 weeks but not overstretching of external rotation.
• Non contact sport at 3 months and contact sport from 6 months.
• N.B. Because there is much less pain, patients must be careful not to overdo or use the shoulder too early and damage the repair.

3. Laser Assisted Capsular Shrinkage (LACS)

Heating collagen tissue such as ligaments, will cause shortening of the fibres and so using a LASER on very low power setting, so that the tissues are only heated to about 60-70°, the shoulder ligaments and capsule can be tightened to the desired tension and thus stabilize an unstable joint.

This may be performed alone, on the patient with the more minor degrees of instability, such as dynamic instability, subluxations and congenital laxity. When the ligaments have been torn off, then they must of course be reattached (through the arthroscope) and then the LASER should be used to tighten them. The results after this combined minimally invasive technique have been very successful in a series published by Phillipe Hardy (Orthopade (1996) 25:91-93).

The operation is much the same as described for the arthroscopic repair, then the LASER probe is passed in a crisscross pattern over the inside of the capsule and anterior ligaments while watching the capsule shrink. The more passes and tissue affected the tighter the joint becomes. The living cells between the "weals" grow into the denatured collagen matrix and lay down new collagen in the shortened position permanently.

The Laser tightening alone is a relatively atraumatic procedure with minimal swelling and pain, therefore there is no need to stay in hospital and rarely any need for analgesia. When an arthroscopic reattachment is undertaken at the same time, the operation takes longer, there may be more swelling and pain and may require one night in hospital.

Postoperative

1. As above but minimal pain and patients often feel immediately the improved stability (tightness) and security.
2. Sling is still worn for 3 weeks to limit free use and increase awareness of the need to protect the healing tissue while maturing and developing strength.
3. Range of movements begins at 1 week under the supervision of the physiotherapist. This is increased progressively to the full range which is obtained by 3 weeks and strengthening exercises are undertaken after this.
4. Driving can be undertaken at 3 weeks, light duties at work when comfortable but restricted by sling (? 2-3 days), no lifting or overhead work for 6 weeks.
5. Non contact sports at 3 months and contact at 6 months to allow maturity of shortened collagen before undue stressing.

These times are dictated by the biological healing times and any short cutting may be associated with risk of damage to the repair and increased risk of redislocation or instability.

Complications:

Complications such as anaesthetic, medical and surgical can occur after any surgery but fortunately are uncommon. The anaesthetist will discuss risks of anaesthesia with you prior to the operation and advise on the safest form (you may contact him/her before the day of surgery if you wish, or your doctor is concerned).

Possible complications with shoulder surgery include:

• infection - we take all steps to minimise this, including covering the operation with an antibiotic
• bleeding, swelling, stiffness and possible nerve injury
• frozen shoulder and/or adhesions - often self limiting, more common in Diabetics and minimised by starting controlled movement early. Muscle tension and spasm tend to make patients more prone to this so must be controlled.
• scar formation is usually minimal because of the arthroscopic technique.
• recurrence of instability - especially if the shoulder is reinjured, or tightening of the capsule is not sufficient, or the capsule stretches out because of abnormal structure of collagen (a cause of the instability in the first place)