The early diagnosis of aseptic loosening of a total hip replacement by plain radiography, scintigraphy and arthrography has been shown to be unreliable. It has been suggested that it may be possible to distinguish between a secure and a loose prosthesis using a vibration technique. We have assessed the use of this technique in vitro using models of early and late loosening. Late loosening with an unstable prosthesis can be reliably detected by vibration analysis, but this method was shown to have a very poor diagnostic sensitivity in early loosening when there is no obvious prosthetic instability

In a prospective study of 132 patients with an average age of 35 years, unstable intra-articular fractures of the distal radius were treated by external fixator. Only 15 cases required limited open reduction. Follow-up was for a mean of 42 months. There were few complications and 83% of patients had good or excellent results. There was a statistically significant correlation between the severity of the fracture and the clinical outcome, irrespective of radiological restoration. Articular and soft-tissue damage following violent compressive forces may lead to a degree of functional impairment

1. The literature on hyperextension injuries of the spine is briefly reviewed. 2. Such injuries in the cervical spine can be subdivided into five groups based on the pathological anatomy, based on the experience of fifty-one patients in the Spinal Injuries Centre for Victoria over the past five years. 3. Extension injuries of the thoraco-lumbar spine are discussed. They are rare and have a poor prognosis. 4. The importance of treatment based on sound clinical and pathological knowledge is emphasised, particularly in order that stable and unstable lesions may be recognised early and managed correctly

Aims

Biofilm formation is intrinsic to prosthetic joint infection (PJI). In the current study, we evaluated the effects of silver-containing hydroxyapatite (Ag-HA) coating and vancomycin (VCM) on methicillin-resistant Staphylococcus aureus (MRSA) biofilm formation.

Ten normal neonatal hips were examined in stillborn babies. At first, forcible Barlow manoeuvres did not produce subluxation or dislocation, but by repeated examination a previously stable joint could be rendered unstable. Dissection of the hips showed that the vacuum fit between the femur and the acetabulum was an important factor in neonatal hip stability. The posterior capsule was not a strong or, in itself, an important structure. It is postulated that the capsule and the labrum act together as 'O' rings to maintain the vacuum fit; it is possible that repeated examinations, by producing an effusion, could break the seal and allow instability

Attempts to eliminate congenital dislocation of the hip by detecting it early have not been completely successful. It is not known why some infants, checked by competent examiners, still appear late with dislocations. The usual explanations of a mistake by the examiner, or of spontaneous dislocation of a hip that was stable at birth, do not explain why some centres succeed while others fail, or why good examiners may become less effective with experience. The explanation suggested is that the examination itself could be responsible and may actually cause a hip to become unstable

Distraction fractures of the upper lumbar spine are most often associated with the wearing of seat-belts. Twenty patients with this spinal fracture were reviewed and half of them had intra-abdominal injuries. Eight patients required an exploratory laparotomy. Three distinct patterns of distraction fractures have been identified. Open reduction, local spinal fusion and Harrington instrumentation are recommended for unstable fractures and for those with neurological involvement. Four cases of non-union are included ln the series. Legislation for the compulsory wearing of seat-belts should encompass improvements in design and stricter criteria for installation

Aims

The aim of this study was to investigate the difference in functional outcome after repair and non-repair of the pronator quadratus muscle in patients undergoing surgical treatment for a distal radial fracture with volar plating.

1. The management of fractures in five patients with haemophilia is described: two patients had antibodies to antihaemophilic globulin. 2. The principles of management of injured haemophilia patients are described, as are the special problems in patients with antibodies to AHG. 3. Stability of the fragments must be achieved to prevent the hazards of displacement of the fracture, recurrent bleeding and pseudotumour formation which may threaten viability of the limb. 4. Stabilisation of potentially unstable fractures can be achieved at the onset by internal fixation. Plaster casts should be reserved for stable fractures or fractures occurring in young children

1. Seventy-five injuries of the cervical spine are reported. Fifty-three were dislocations and fracture-dislocations involving the third to the seventh segments. 2. The importance of careful examination in all neck injuries is stressed. 3. The injuries are divided into stable and unstable types and the causation of the instability is discussed. 4. Plaster immobilisation for more than six months failed in some patients to prevent recurrence of dislocation. 5. Operative treatment was advised in all cases of dislocation, the spine being wired and grafted with iliac bone. This prevents recurrence and shortens the period of convalescence

1. The problem of paralytic hip instability has been studied in a series of twenty-one patients brought to a spina bifida clinic. 2. Thirty iliopsoas tendon transfers were done in an attempt to reduce deformity and improve hip stability. 3. At the time of review, ten of these hips were stable and twenty were unstable. Ten hips were improved by operation, and one hip was worse. The other nineteen remained the same. 4. All of the children except one were capable of walking with an orthotic device. 5. Some of the complexities of the problem of paralytic hip instability in the patient with myelomeningocele are discussed

We investigated the clinical and radiological outcome after unilateral fracture of the lateral process of the talus in 23 snowboarders with a mean follow-up of 3.5 years (12 to 76 months). In this consecutive cohort study both operative and non-operative cases were considered. The mean American Orthopaedic Foot and Ankle Society hindfoot score was 94 (82 to 100). The non-operative group of seven with a minimally-displaced fracture scored higher (98 points) than the operative group of 16 with displaced or unstable fractures (93 points). In 88% of operative cases, significant concomitant hindfoot injuries were found at operation. All but eight (35%) patients (six operative and two non-operative) regained their pre-injury level of sporting activity. Subtalar osteoarthritis was present in nine (45%) of the 20 patients available for radiological review, including one late-diagnosed non-operative case and eight operative cases with associated injuries or fracture comminution. The outcome after fracture of the lateral process of the talus in snowboarders is favourable provided an early diagnosis is made and adequate treatment, which is related to the degree of displacement and associated injuries, is undertaken

We classified fractures of the base of the middle phalanx into five types: 1) single palmar fragment; 2) single dorsal fragment; 3) two main fragments; 4) not involving the articular surface, including epiphyseal separation in children; and 5) all others. Types 1 and 2 were subclassified into avulsion, split and split-depression. Surgery is recommended for unstable type-1 avulsion fractures, type-2 avulsions which may develop buttonhole deformities, and all fractures which displace articular cartilage surfaces. Long-term follow-up showed that surgical treatment which produced good stability and congruity gave good results. These should be the primary aims of treatment

Aims

The aim of this study was to review the value of accepting referrals for children with ‘clicky hips’ in a selective screening programme for hip dysplasia.

Various techniques have been used for the fixation of the posterior pelvis, each with disadvantages specific to the technique. In this study, a new protocol involving the placement of posterior pelvic screws in the CT suite is described and evaluated. A total of 66 patients with unstable pelvic ring injuries was stabilised under local anaesthesia with sedation. The mean length of time for the procedure was 26 minutes per screw. There were no technical difficulties or misplaced screws and no cases of infection or nonunion. All patients stated that they would choose to have the CT scan procedure again rather than a procedure requiring general anaesthesia. The charges for the procedure were approximately £1840 ($2800) per operation. CT-guided placement of iliosacral screws is a safe, feasible, and cost-effective alternative to radiologically-guided placement in the operating theatre in selected patients

A simple procedure of using a Smillie knife to release the lateral patellar retinaculum and the capsule in the unstable patella syndrome is described. The syndrome includes recurrent dislocation, recurrent subluxation and acute dislocation of the patella. Arthroscopy, to exclude any other pathology such as chondromalacia patellae, is performed before proceeding to closed lateral release. The results of this procedure are as good as those after more major surgical procedures. In a small percentage of patients a second operation such as tibial tubercle transfer or patellectomy may be necessary, especially in patients with an underlying congenital abnormality; but in many patients this type of major surgery has proved unnecessary

The range of rotation of the talus in the horizontal plane was studied in the cadaveric ankle under conditions which simulated normal load-bearing. In the unloaded state there was 25 degrees of rotation, approximately half of which resulted from movement of the inferior tibiofibular joint. Rotation was load-dependent in both the intact ankle and in the ankle rendered unstable by division of the ligaments. Experimental division of the ligaments increased the range of rotation. The malleoli were contact areas during flexion and extension but excision of their articular surfaces caused only a moderate increase in rotation. The factors which limit talar rotation in intact and injured ankles are discussed

Six highly unstable elbows with severe bone loss due to rheumatoid arthritis were replaced by a non-constrained, unlinked prosthesis. Bone defects were filled with autogenous bone grafts. The mean follow-up was 4.5 years (2 to 8). The clinical results were excellent in four elbows and good in two, with good varus-valgus stability in all. Radiological follow-up showed no appreciable signs of loosening, and the bone grafts had retained most of their original size, with minimal resorption. There were no major complications such as dislocation, skin necrosis, infection or ulnar neuropathy. The study has shown that the so-called mutilans elbow can be successfully replaced using a properly selected type of non-constrained, unlinked prosthesis with bone grafting of the major defects