We studied five cadaver shoulders to determine the strength relationship of the four rotator cuff muscles. The mean fibre length and volume of each muscle were measured, from which the physiological cross-sectional area was calculated. This value was used to estimate the force which each muscle was capable of generating. The lever arm of each muscle about the humeral head was then measured and the moment exerted was calculated. The strength ratios between the muscles were more or less constant in the five specimens. Subscapularis was the most powerful muscle and contributed 53% of the cuff moment; supraspinatus contributed 14%, infraspinatus 22% and teres minor 10%. The force-generating capacity of the subscapularis was equal to that of the other three muscles combined

We describe 11 cases of posterior fracture-dislocation of the shoulder that required open reduction and fixation. Difficulties with access through anterior approaches led us to use the superior subacromial approach. This is an extension of the approach often used to expose the rotator cuff; the joint is opened by splitting the supraspinatus tendon 5 mm behind the cuff interval. The glenoid, proximal humerus and any fracture fragments can be seen from above, allowing reduction of the dislocation and osteosynthesis to be performed with minimal risk of damage to the humeral head and its blood supply. The proximity of the axillary nerve limits the exposure of the proximal humeral shaft. The superior subacromial approach is ideal for posterior dislocation with fracture of the articular segment, but is not suitable when there is a fracture of the proximal humeral shaft

Open reduction and internal fixation was employed in the treatment of 25 severely displaced fractures and fracture-dislocations of the proximal humerus. Our aims were accurate reduction and stable fixation to allow early mobilisation and to achieve full functional recovery. In 15 fractures an AO T-plate was used and in 10 a bent semitubular plate was employed as a blade plate. Excellent or satisfactory results were obtained in all six patients with two-part fractures involving the surgical neck; in four of the five patients with three-part fractures involving the surgical neck and tuberosities; in nine of the 11 patients with fracture-dislocation; and in two of the three patients with split fractures of the humeral head. Overall results were good or satisfactory in 21 of the 25 cases. Unsatisfactory results were associated with rotator cuff damage

We reviewed eight children (ten shoulders) who had suffered neonatal sepsis, after a mean follow-up of 14 years (11 to 15). The delay between the onset of symptoms and diagnosis was one day in five patients, two days in three and seven days in one. All ten shoulders were treated by aspiration, followed by arthrotomy in two. At follow-up, five of the ten shoulders had a full range of movement and the others had minimal restriction of external rotation. Shortening of 10 cm was present in one patient, while two with bilateral involvement had disproportionally short humeri. Early diagnosis and treatment favour the outcome in septic arthritis of the shoulder. With late diagnosis, deformation of the humeral head and shortening of the humerus cause marked cosmetic abnormality but negligible functional loss

We treated 12 shoulders in ten patients with irreparable rotator-cuff tears by transfer of the latissimus dorsi. There were nine men and one woman. Their average age was 64.0 years and the average follow-up was 35.6 months (26 to 42). The results were excellent in four shoulders, good in four, fair in one, and poor in three. Active forward flexion improved from a preoperative average of 99° to a postoperative average of 135°. Osteoarthritic changes appeared in five shoulders and proximal migration of the humeral head progressed in six. EMG revealed that nine of the 12 transferred muscles showed activity which was synergistic with the supraspinatus on external rotation with abduction. We conclude that latissimus dorsi transfer can be effective in restoring shoulder function after massive irreparable tears of the rotator cuff

1. Six cases of posterior dislocation of the shoulder are described. 2. In four cases the diagnosis was made on clinical grounds. 3. The important clinical signs are the adducted and medially rotated position of the arm, a hard mass posteriorly below the acromion representing the displaced humeral head, and limitation of movement, especially abduction and lateral rotation. 4. In two cases the dislocation was not recognised at the first examination. This confirms the statement of previous authors that posterior dislocation is easily missed. 5. The value of the vertical projection in the radiography of suspected posterior dislocation is emphasised. 6. Reduction was accomplished without difficulty in five cases and the subsequent progress of these was uneventful. In the remaining case reduction was difficult and unstable, and the final recovery incomplete. It is considered that this patient would have been better treated by early open reduction

The operative treatment of fractures of the proximal humerus can be complicated by poor bone quality. Our aim was to evaluate a new method which allows prediction of the bone quality of the proximal humerus from radiographs. Anteroposterior radiographs were taken of 19 human cadaver humeri. The cortical thickness was measured at two levels of the proximal humeral diaphysis. The bone mineral density (BMD) was determined for the humeral head (HH), the surgical neck (SN), the greater tuberosity (GT) and lesser tuberosity (LT) using dual-energy x-ray absorptiometry. The mean cortical thickness was 4.4 ± 1.0 mm. Specimens aged 70 years or less had a significantly higher cortical thickness than those aged over 70 years. A significant positive correlation was found between cortical thickness and the BMD for each region of interest. The cortical thickness of the proximal diaphysis is a reliable predictor of the bone quality of the proximal humerus

We examined macroscopically and microscopically 55 cadaver rotator-cuff tendons attached to their humeral heads to determine the distance between the edge of the articular cartilage and the tendon insertion of the supraspinatus (the width of the sulcus) and the score of regressive changes at the sulcus. In 33 specimens we measured the tensile strength. The width of the sulcus was correlated with the score of regressive changes and with the ultimate tensile strength of the supraspinatus tendon. The width of the sulcus correlated positively with the score of regressive changes (r = 0.66, p < 0.0001), but there was a negative correlation between the latter and the ultimate tensile strength (r = −0.81, p = 0.001) and between the width of the sulcus and the ultimate tensile strength (r = −0.74, p = 0.004). We believe that the width of the sulcus is a simple and useful clinical indicator of the integrity and the tensile strength of the supraspinatus tendon

We performed a prospective study using MRI in 16 consecutive infants with a mean age of 5.2 months (2.7 to 8.7) who had shown inadequate recovery from an obstetric lesion of the brachial plexus in the first three months of life, in order to identify early secondary deformities of the shoulder. Shoulders were analysed according to a standardised MRI protocol. Measurements were made of the appearance of the glenoid, glenoid version and the position of the humeral head. The appearance of the glenoid on the affected side was normal in only seven shoulders. In the remainder it was convex in seven and bioconcave in three. The degree of subluxation of the humeral head was significantly greater (p = 0.01) in the affected shoulders than in normal shoulders (157° v 170°). The presence of an abnormal appearance of the glenoid, retroversion of the glenoid and subluxation of the humeral head increased with age. There was a statistical difference (p = 0.05) between infants younger than five months and those who were older

Ninety-five patients with steroid-induced avascular necrosis of bone have been personally treated by the author. Of these, eighteen had a lesion of the head of the humerus, on one or both sides. The conditions for which the steroids were given included post-transplantation, lupus erythematosus, glomerulonephritis and asthma. The characteristic lesion began as a subchondral osteolytic area which frequently progressed to collapse. The articular cartilage divided from the subchondral bone, either becoming detached as a free cap or at a later stage reattaching. In some cases the lesion was minimal and the symptoms were slight. Conservative treatment has consisted of pendulum exercises and avoidance of abduction, particularly against resistance. In fourteen patients this led to satisfactory function with only intermittent symptoms. Four patients required replacement of five humeral heads with Neer's prostheses. After one to seven years the results of all five were classified as excellent in terms of absence of symptoms and a free range of movement

The purpose of this paper is to call attention to the anterior bone block method of Hybbinette-Eden for recurrent dislocation of the shoulder joint. 1. The operative technique is not difficult, and the after-treatment is short and relatively agreeable for the patient. 2. Sixty of our own cases are described, with four recurrences. The recurrences all occurred as the result of real trauma. In a total of 128 Scandinavian cases there were eight recurrences—that is 6·3 per cent. 3. In our opinion, based on the observations of radiography, arthrography, and operation, it is the compression fracture of the head of the humerus which deserves the name "essential lesion." Destruction of the anterior rim of the glenoid may be very slight, or entirely lacking. No false joint cavity or rupture big enough to receive the head of the humerus was ever observed by arthrography or by inspection during operative exploration. Recurrent dislocation is an intracapsular subluxation, which occurs when the anterior rim of the glenoid slides into the hollow in the humeral head

The stabilising effects on the glenohumeral joint of each of the rotator-cuff muscles and of the biceps were studied with the arm in abduction and external rotation in 13 cadaver shoulders. The muscles were loaded one at a time with forces proportional to their cross-sectional areas. We recorded the positions of the humeral head before and after the application to the humerus of an anterior force of 1.5 kg. When the capsule was intact, the anterior displacement with the subscapularis loaded was significantly larger than with the other muscles loaded (p = 0.0009). With the capsule vented, the displacement with the biceps loaded was significantly smaller than that with the subscapularis loaded (p = 0.0052). After creating an imitation Bankart lesion, the displacement with the biceps loaded was significantly less than with any of the rotator-cuff muscles loaded (p = 0.0132). We conclude that in the intact shoulder, the subscapularis is the least important anterior stabiliser, and that the biceps becomes more important than the rotator-cuff muscles as stability from the capsuloligamentous structure decreases. Strengthening of the biceps as well as the rotator-cuff muscles should be part of the rehabilitation programme for anterior shoulder instability

Aims

The Mathys Affinis Short is the most frequently used stemless total shoulder prosthesis in the UK. The purpose of this prospective cohort study is to report the survivorship, clinical, and radiological outcomes of the first independent series of the Affinis Short prosthesis.

1. A study of 2,200 patients receiving electro-convulsive therapy showed that fifty-three sustained fractures or dislocations—an incidence of 2·4 per cent. Of the fifty-three injuries, twenty-one occurred in the spine, fifteen in the neck of femur, fifteen in the upper end of humerus, one in the coracoid process; one dislocated jaw required anaesthesia for its reduction (other cases of transient dislocation of the jaw are excluded). 2. The incidence, site, and type of spinal fractures are recorded, and the relation of the fracture to the first convulsion is noted. No late changes were found in the spines of patients examined two years or more after treatment. A neutral position of the spine during the convulsion is believed to diminish the risk of fracture. 3. Fracture of the neck of the femur is a serious injury in these patients. In one case the injury was bilateral. 4. The fifteen cases of fracture-dislocation of the upper humerus are analysed. They included two cases of posterior dislocation of the humeral head; the possible mechanism of this is explained and a method of prevention suggested. 5. Fifty-three patients with chronic epilepsy with psychosis were examined. Four cases of fractured spine were discovered. The site of fracture was different from that of fractures caused by convulsive therapy and a reason for this is suggested. The type and mechanism of the fracture are similar in the two groups

Aims

To report early (two-year) postoperative findings from a randomized controlled trial (RCT) investigating disease-specific quality of life (QOL), clinical, patient-reported, and radiological outcomes in patients undergoing a total shoulder arthroplasty (TSA) with a second-generation uncemented trabecular metal (TM) glenoid versus a cemented polyethylene glenoid (POLY) component.

Aims

Reverse total shoulder arthroplasty (RTSA) using trabecular metal (TM)-backed glenoid implants has been introduced with the aim to increase implant survival. Only short-term reports on the outcomes of TM-RTSA have been published to date. We aim to present the seven-year survival of TM-backed glenoid implants along with minimum five-year clinical and radiological outcomes.

Aims

The amount of glenoid bone loss is an important factor in deciding between soft-tissue and bony reconstruction when managing anterior shoulder instability. Accurate and reproducible measurement of glenoid bone loss is therefore vital in evaluation of shoulder instability and recommending specific treatment. The aim of this systematic review is to identify the range methods and measurement techniques employed in clinical studies treating glenoid bone loss.

Aims

The purpose of this study was to report bone adaptive changes after anatomical total shoulder arthroplasty (TSA) using a standard-length hydroxyapatite (HA)-coated humeral component, and to report on a computer-based analysis of radiographs to determine changes in peri-implant bone density objectively.