The capsular shift procedure is done to treat instability due to ligamentous laxity. Usually there is no traumatic avulsion of the labroligamentous tissues.

In surgical repair the anterior labrum is separated from the glenoid. The labrum and attached ligaments are shifted superiorly and attached with bone anchors to the decorticated glenoid. The labrum and ligaments are rolled into a soft tissue ‘bumper’ (we refer to this as labroplasty). Arthroscopic rotator interval plication is added to the procedure.

For six months to six years we followed up 67 patients treated between 1994 and 2000. There were two cases of recurrent subluxation (3%). Patient satisfaction was high.

The acromion is a bony process that juts out from the lateral end of the scapular spine. It is continuous with the blade and the spinous process. The process is rectangular, and carries a facet for the clavicle. Inferiorly is sited the subacromial bursa. Inferior encroachment or displacement of the acromion can result in impingement.

The aim of this osteological study was to assess the presence of acromial displacement and variations predisposing to compaction of the subacromial space. Using the method described by Morrison and Bigliana, we assessed the scapulae of 128 men and women ranging from 35 to 92 years of age. We found a flat acromion in 30%, no hook in 48%, a small hook in 18% and a large hook in 4%. The presence of a hook was associated with a subacromial facet and a large hook with glenoid erosion.

This study confirms the presence of four types of acromion.

We discuss aspects of glenohumeral instability and rotator cuff tears in a clinically orientated approach, presenting a new way of quantifying structural bone loss from the anterior glenoid and defining the Glenoid Index as an indicator of the appropriate surgical approach to address anterior instability.

Repair of the rotator cuff depends on viable and functional muscular tissue. We discuss the potential for repair of the supraspinatus tendon in relation to the tangent sign, fat infiltration and retraction. Comparing MRI and arthroscopic findings, we highlight pitfalls in the diagnosis and repair of the subscapularis tendon.

Painful conditions of the acromioclavicular (AC) joint are common in South Africa, particularly among sportsmen. These conditions are often treated by open excision of the distal end of the clavicle, but an arthroscopic procedure offers many advantages.

From February 1994 to February 2000, we performed 138 procedures. The mean age of patients ({71% men and 29% women) was 29 years (19 to 53). In cases of rotator cuff impingement, arthroscopic acromioplasty was followed by clavicular excision via the subacromial route. With a normal acromion and rotator cuff the AC joint was approached through two superior AC portals, avoiding removal of the AC ligaments. In all cases a standard 3.5-mm arthroscope was placed in one portal for viewing and the mechanical shaver inserted through the other. About 7 mm to 8mm of bone was removed from the clavicle. Patients were in hospital for about a day and 87% were discharged the same day.

The mean follow-up time was 34 months (2 months to 4 years). Patient satisfaction was high in 32%, fair in 60% and poor in 8%. Most patients (92%) returned to all previous sports and activities.

We concluded that the arthroscopic Mumford procedure is at least as successful as its open equivalent. It can be done as an outpatient procedure and permits a rapid return to activities. Cosmesis is excellent and stability of the AC joint is preserved.

The rotator cuff is sited on the anatomical neck of the humerus and is formed by the insertion of the supraspinatus (SP), infraspinatus (IS), teres minor (TM) and subscapularis. All play a vital role in the movement of the glenohumeral joint, and the anatomy is of critical importance in arthroscopic rotator cuff repair. We undertook an osteological and gross anatomical dissection study of the insertion mechanism of these tendons, in particular the SP .

The SP inserts by a triple or quadruple mechanism. The ‘heel’ (medial) and capsule fuse, inserting into the anatomical neck proximal to the anterior facet of the greater humeral tubercle. The ‘foot arch’ inserts as a strong, flat, fibrous tendon into the facet. This area is cuboidal, rectangular, or ellipsoid, and measures 36 mm² to 64 mm². In about 5%, the insertion is fleshy (pitted), rendering it weaker than a tendinous attachment. The ‘toe’ lips over the edge of the facet laterally and fuses with the periosteum, fibres of the inter-transverse ligament and the IS. A proximal ‘hood’ of about 4 mm stretches down inferiorly and fuses with the periosteum of the humeral shaft. The subacromial or subdeltoid synovial bursa are sited laterally.

The IS and TM insert into the middle and posterior facets (225 mm and 36 mm²) at respective angles of 80° and 115°. The inferior portion of the TM facet is not fused with the shoulder capsule. The subscapularis inserts broadly into the lesser tubercle, and the superior fibres fuse with the shoulder capsule and intertransverse ligament. The insertion of the subscapularis does not contribute directly to the formation of the ‘hood’, which belongs exclusively to the SP, IP and TM.

This study confirms the complexity of the SP insertion and suggests that an unfavourable attachment or biomechanical anatomical malalignment may lead to eventual tendon/cuff degeneration.