Using a dynamic biomechanical model of malunion of the shoulder, we have determined the change in deltoid force required for abduction with various combinations of superior and posterior displacement of fractures of the greater tuberosity of the humerus. We tested eight fresh human cadaver shoulders in a dynamic shoulder-testing apparatus during cycles of glenohumeral abduction from 0° to 90°. The greater tuberosities were osteotomised and stabilised to represent malunion with combinations of superior and posterior displacements of 1 cm and less. The peak force was measured for each displacement in each specimen and statistically compared with values of no displacement using a repeated-measures analysis of variance. The abduction force was significantly increased by 16% (p = 0.006) and 27% (p = 0.0001) by superior displacements of 0.5 cm and 1 cm, respectively, while combined superior and posterior displacement of 1 cm gave an increase in force of 29% (p = 0.001). While treatment criteria for acceptable residual displacement of the greater tuberosity are widely used, there is little information on the direct biomechanical effects of displacement on shoulder mechanics. Although the results of conservative treatment are influenced by a number of factors, including associated injuries, rehabilitation and the pre-existing function of the shoulder, our data suggest that small amounts of residual displacement may alter the balance of forces required to elevate the arm at the glenohumeral joint

Most brachial plexus palsies are due to trauma, often resulting from motorcycle accidents. When nerve repair and physiotherapy are unsuccessful, muscle transfer may be considered. Paralysis of the deltoid and supraspinatus muscles can be addressed by transfer of the trapezius. Between March 1994 and June 1997 we treated 38 patients with brachial plexus palsy by trapezius transfer and reviewed 31 of these (7 women, 24 men) after a mean follow-up of 23.8 months (12 to 39), reporting the clinical and radiological results and subjective assessment. The mean age of the patients was 29 years (18 to 46). The operations had been performed according to the method of Saha described in 1967, involving transfer of the acromion with the insertion of the trapezius to the proximal humerus, and immobilisation in an abduction support for six weeks. Rehabilitation started on the first postoperative day with active exercises for the elbow, hand and fingers, and electrical stimulation of the transferred trapezius. All 31 patients had improved function with a decrease in multidirectional instability of the shoulder. The average increase in active abduction was from 7.3° (0 to 45) to 39° (25 to 80) at the latest review. The mean forward flexion increased from 20° (0 to 85) to 44° (20 to 90). Twenty-nine of the 31 were satisfied with the improvement in stability and function. Trapezius transfer for brachial plexus palsy involving the shoulder improves function and stability with clear subjective benefits

Autogenous bone graft which has been either autoclaved or irradiated is commonly used in oriental countries as an alternative to allograft. We started to use the technique of extracorporeal irradiation of the resected specimen and reimplantation (ECIR) in 1991. There was, however, a high incidence of fracture of the irradiated bone and loss of articular cartilage. In an attempt to reduce these complications, we combined the irradiated autograft with a conventional arthroplasty. Between 1995 and 1998, 14 patients underwent limb salvage by this method. Seven had an osteosarcoma, two bony metastases, three a chondrosarcoma, one a malignant fibrous histiocytoma, and one a leiomyosarcoma. Ten tumours were located in the proximal femur, two in the proximal humerus, and two in the distal femur. One patient who had a solitary metastasis in the proximal part of the left femur died from lung metastases 13 months after operation. The remaining 13 patients were alive and without evidence of local recurrence or distant metastases at a mean follow-up of 43 months (28 to 72). Postoperative palsy of the sciatic nerve occurred in one patient, but no complications such as wound infection, fracture, or nonunion were seen. All host-irradiated bone junctions healed uneventfully within eight months. Using the Enneking functional evaluation system, the mean postoperative score for all 14 patients was 80% (57 to 93). The use of irradiated autograft prosthesis composites reduces the complications of ECIR and gives good functional results. It may be a good alternative in limb-salvage surgery, especially in countries where it is difficult to obtain allografts

Aims

The aim of this study was to analyze the results of two radiocapitellar prostheses in a large case series followed prospectively, with medium-term follow-up.

1. Analyses are presented of comparable groups of the two commonest bone-forming tumours—osteochondroma and osteogenic sarcoma—derived from the following sources: Bristol Bone Tumour Register; British Empire Cancer Campaign Annual Report (1949); Stocks and Barrington (1925); Meyerding (1927); and Geschickter and Copeland (1949). 2. From this study, the following features emerge as characteristic and common to both tumours. 1) Both tumours are commoner in the male during the age periods 0-34 years, and over fifty years, with the possible exceptions of tumours of the humerus during early life and tumours of the pelvis. 2) The male preponderance is most marked for the appendicular long bones. 3) The male preponderance is greatest during the age period 15-34 years. 4) In the separate bones, these tumours tend to arise at a somewhat earlier age in the female. 5) In both sexes both tumours tend to arise at an earlier age in the bones of the upper arm and shoulder girdle than in those of the lower limb and pelvis. 6) Both tumours are related to an aberration of endochondral growth in length of bone. 3. The greater growth of the male, and differences in skeletal development in the two sexes, offer a simple and reasonably consistent explanation of these peculiarities and make it possible to discern the interplay of the three factors of age, sex and site of origin of the tumour. 4. From this concept it is possible to make a crude estimate of the factors of time and bulk of tissue which when combined may well account for the observed male preponderance of these tumours, and their anatomical distribution

Surgical treatment for traumatic, anterior glenohumeral instability requires repair of the anterior band of the inferior glenohumeral ligament, usually at the site of glenoid insertion, often combined with capsuloligamentous plication. In this study, we determined the mechanical properties of this ligament and the precise anatomy of its insertion into the glenoid in fresh-frozen glenohumeral joints of cadavers. Strength was measured by tensile testing of the glenoid-soft-tissue-humerus (G-ST-H) complex. Two other specimens of the complex were frozen in the position of apprehension, serially sectioned perpendicular to the plane containing the anterior and posterior rims of the glenoid, and stained with Toluidine Blue. On tensile testing, eight G-ST-H complexes failed at the site of the glenoid insertion, representing a Bankart lesion, two at the insertion into the humerus, and two at the midsubstance. For those which failed at the glenoid attachment the mean yield load was 491.0 N and the mean ultimate load, 585.0 N. At the glenoid region, stress at yield was 7.8 ± 1.3 MPa and stress at failure, 9.2 ± 1.5 MPa. The permanent deformation, defined as the difference between yield and ultimate deformation, was only 2.3 ± 0.8 mm. The strain at yield was 13.0 ± 0.7% and at failure, 15.4 ± 1.2%; therefore permanent strain was only 2.4 ± 1.1%. Histological examination showed that there were two attachments of the anterior band of the inferior glenohumeral ligament at the site of the glenoid insertion. In one, poorly organised collagen fibres inserted into the labrum. In the other, dense collagen fibres were attached to the front of the neck of the glenoid

Aims

The aim of this study was to investigate the local recurrence rate at an extended follow-up in patients following navigated resection of primary pelvic and sacral tumours.

Aims

The aim of this study was to report the outcomes of patients who underwent definitive surgery for secondary chondrosarcomas arising from osteochondromas.

Out of 21 900 cases filed at the Latin-American Registry of Bone Pathology between April 1940 and July 1981, there were 987 with Paget's disease (4.51 per cent); 62 of these (6.28 per cent) were complicated by sarcoma and two were associated with giant-cell tumours of bone (osteoclastoma) without signs of malignancy. There was a slight predominance of men and the ages ranged from 45 to 87 years, with an average of 66 years. The most frequent sites were the femur (23 cases), the humerus (nine), the pelvis (10), and the tibia (nine). The low incidence of vertebral involvement (five cases) is noteworthy and is in sharp contrast to uncomplicated Paget's disease. The most common tumour type was osteosarcoma (39 cases), followed by fibrosarcoma (15 cases); other varieties (chondrosarcoma, malignant fibrous histiocytoma and reticulum-cell sarcoma) were much rarer. Most of the sarcomata occurred when the Paget's disease was polyostotic. Tumours often developed simultaneously, or at short time intervals, in the same or different bones; these bones had, in all cases, been affected by Paget's disease. The histological features of the osteosarcomata were characteristic, with large numbers of osteoclast giant cells, alternating with atypical osteoblasts, thus exaggerating the anarchic remodelling process of Paget's disease. The neighbouring areas of the pagetic bone showed an increased number of osteoclasts. These facts suggest a possible pathogenetic relationship between sarcoma and Paget's disease; the possibility of both processes having a viral aetiology is discussed

The histodynamic response to long-term "non-traumatic" immobilisation was studied in young adult Beagle dogs by means of radiomorphometry and histomorphometry, the right forelimb being encased in plaster and the left forelimb serving as a control. The dogs were killed at two, four, six, eight, twelve, sixteen, twenty, twenty-four, thirty-two and forty weeks and the third metacarpal, radius, ulna and humerus removed for analysis of the contributions of the periosteal, haversian and endosteal envelopes to the bone loss at the mid-diaphysis. The bone mass responded to long-term immobilisation in three stages. First there was a rapid initial loss of bone, reaching its maximum (some 16 per cent of original mass) at six weeks, to which all three bone envelopes, to some extent, contributed. A rapid reversal followed, the bone mass approaching the control values between eight and twelve weeks after immobilisation. A second stage of slower but longer lasting bone loss ended twenty-four to thirty-two weeks after immobilisation; the periosteal envelope was the main contributor (80 to 90 per cent of the total loss). The third stage was characterised by maintenance of the bone mass which had been reduced by some 30 to 50 per cent of original values. This pattern was qualitatively similar in all four bones but the distal bones lost more bone than the proximal bones. The extent of resorption surface and the total histologically "active" periosteal envelope increased parallel to the phases of bone loss. The linear mineralisation rate did not differ significantly between the experimental and control sides

Aims

The purpose of this study was to compare the effectiveness of surgical repair to conservative treatment and subacromial decompression for the treatment of chronic/degenerative tears of the rotator cuff.

Aims

The aim of this study was to determine the risk of local recurrence and survival in patients with osteosarcoma based on the proximity of the tumour to the major vessels.

Aims

Delayed diagnosis is a well-known complication of a Monteggia fracture-dislocation. If left untreated, the dislocated radial head later becomes symptomatic. The purposes of this study were firstly, to evaluate the clinical and radiological results of open reduction of the radial head and secondly, to identify the factors that may affect the outcome of this procedure.