We have tested the hypothesis that the meniscofemoral ligaments make a significant contribution to resisting anteroposterior and rotatory laxity of the posterior-cruciate-ligament-deficient knee. Eight cadaver human knees were tested for anteroposterior and rotatory laxity in a materials-testing machine. The posterior cruciate ligament (PCL) was then divided, followed by division of the meniscofemoral ligaments (MFLs). Laxity results were obtained for intact, PCL-deficient, and PCL-MFL-deficient knees. Division of the MFLs in the PCL-deficient knee increased posterior laxity between 15° and 90° of flexion. Force-displacement measurements showed that the MFLs contributed 28% to the total force resisting posterior drawer at 90° of flexion in the intact knee, and 70.1% in the PCL-deficient knee. There was no effect on rotatory laxity. This is the first study which shows a function for the MFLs as secondary restraints to posterior tibial translation. The integrity of these structures should be assessed during both imaging and arthroscopic studies of PCL-injured knees since this may affect the diagnosis and management of such injuries

We made a prospective study of 58 patients with suspected internal derangement of the knee. They were examined by magnetic resonance imaging using 3-D gradient echo intermediate-weighted studies before having an arthroscopy. The preoperative clinical assessment was found to have a diagnostic sensitivity of 77% and a specificity of 43%, compared with 100% and 63% respectively for magnetic resonance imaging. Comparison of magnetic resonance imaging and arthroscopy confirmed the accuracy of magnetic resonance imaging in the diagnosis of internal derangement but the results for articular cartilage lesions were much less good, with a sensitivity of only 18% but a specificity of 100%. Acceptance of the magnetic resonance imaging findings could have resulted in a 29% reduction in the number of arthroscopies without missing any significant meniscal lesion

We reviewed 275 cases and calculated the prevalence of bacteriologically or radiologically confirmed acute haematogenous osteomyelitis in children under 13 resident in Greater Glasgow during 1970 to 1990. In the 20-year period there was a fall of over 50%, mainly involving cases of long-bone infection, and those due to Staphylococcus aureus. There was a reduced incidence of complications. The proportion of cases involving long bones decreased from 84% to 57%, and those of Staphylococcus aureus infection from 55% to 31%. These changes, in what is becoming a rare disease, need to be known to ensure early diagnosis and adequate treatment, particularly of subacute non-staphylococcal infection at unusual sites

We diagnosed 50 patients (58 shoulders) with a mean age at presentation of 17.3 years, as having involuntary positional instability of the shoulder. They were managed by a programme consisting of a careful explanation, analysis of abnormal muscle couples and then muscle retraining carried out by a specialist physiotherapist. The mean follow-up was two years. Six shoulders had a poor result, but 52 were graded as good to excellent. Nine patients (12 shoulders) relapsed and required further episodes of retraining. In our experience, involuntary positional instability of the shoulder causes symptoms which interfere with normal activities; these can be controlled by a treatment plan of retraining of the muscle pattern with functional benefit. Only 19 of the patients were referred with a diagnosis of positional instability. There should be more awareness of this rather uncommon condition. Surgery is not indicated in these patients

We reviewed a series of 91 patients with deep infection of a cemented total hip arthroplasty caused by coagulase-negative staphylococci (C-NS). Of these, 72 were treated by one-stage exchange arthroplasty with a failure rate of 13% due to recurrence of infection. The other 19 patients have started or completed treatment by a two-stage exchange without failure to date. In 27 of the 91 patients multiple strains of C-NS were discovered, many being resistant to previously used antibiotics. The use of gentamicin-containing cement in the primary arthroplasty was significantly associated with the emergence of gentamicin-resistant C-NS in subsequent deep infection. Bacteriological diagnosis of such infections must take into consideration the possibility that multiple strains of the organism are involved

In a retrospective review of 302 clinically suspected cases of congenital syphilis, bone changes were found in 197. The skeletal manifestations were periostitis (102 cases), osteitis (20), and metaphyseal changes (71). Combinations of more than one lesion were found in 61. Pseudoparalysis was a presenting sign in 34 infants; 12 of these were found to have had pathological fractures and four had dactylitis. Complete radiological healing without residual changes was seen in all 59 cases that were recalled for review. The orthopaedic surgeon should consider the diagnosis of congenital syphilis when destructive lesions of bone are seen in an infant

We have analysed associated factors in 164 patients with acute compartment syndrome whom we treated over an eight-year period. In 69% there was an associated fracture, about half of which were of the tibial shaft. Most patients were men, usually under 35 years of age. Acute compartment syndrome of the forearm, with associated fracture of the distal end of the radius, was again seen most commonly in young men. Injury to soft tissues, without fracture, was the second most common cause of the syndrome and one-tenth of the patients had a bleeding disorder or were taking anticoagulant drugs. We found that young patients, especially men, were at risk of acute compartment syndrome after injury. When treating such injured patients, the diagnosis should be made early, utilising measurements of tissue pressure

Ten children who had clinically stable hips at birth were radiographed at one month because they had factors predisposing to hip dislocation. In all cases one or both hips gave rise to a suspicion of dysplasia, though clinical abnormalities were slow to appear. Four of these hips subsequently dislocated. We believe that infants with late presentation of acetabular dysplasia and clinical abnormality belong to a different aetiological group from those with neonatal instability due to ligamentous laxity. The significance of this differentiation is that some infants presenting late have only recently dislocated, and the diagnosis has not necessarily been "missed" at neonatal examination

The clinical and pathological features of six cases of desmoplastic fibroma of bone are presented. Desmoplastic fibroma is rarely seen as a primary tumour of bone; when it does occur the sites of predilection are the long bones, but other sites such as the scapula and os calcis can be involved. Radiographically the lesion tends to expand the bone from within; it is well-demarcated and lytic, often with a trabeculated soap-bubble appearance. The cellular structure and the morphological arrangement are similar to those of aggressive fibromatosis of soft tissues. Differential diagnosis from malignant spindle-cell lesions of bone is important because the treatment of choice for desmoplastic fibroma of bone is simply excision with a thin layer of healthy tissue

The operative and anaesthesic technique for 44 patients undergoing posterior spinal fusion with Harrington rod instrumentation for idiopathic scoliosis is described. There were two groups of 21 and 23 patients, matched for diagnosis and status before operation. The management of both groups was similar but in one group anaesthesia with induced hypotension was employed, using a mixture of sodium nitroprusside and trimetaphan. The mean blood loss at operation and after operation in this group was significantly lower than in the other group, with a consequent reduction in the transfusion requirement. No adverse sequelae were observed. All patients showed a drop in haemoglobin concentration after operation, despite clinically adequate blood transfusion

The clinical and radiological features in three cases of cystic angiomatosis of bone are reported. Although these features are generally diagnostic except from histiocytosis X, the definitive diagnosis must be established by a pathological study, preferably of a segment of an involved rib or fibula. The prognosis varies according to the type of clinical presentation-in particular upon whether the lesions are solely skeletal or whether there is extraskeletal visceral involvement. Whereas these last cases may often prove fatal, those with only skeletal involvement have a favourable prognosis: indeed, the cystic bone lesions may regress without any treatment, as occurred in some cases reported in the literature and in two of our three cases

1. Twenty-two cases of synovial rupture of the knee have been studied. This condition may complicate any chronic synovitis of the knee in which a tense intra-articular effusion is subjected to increased tension during flexion and extension of the joint. 2. Two types of rupture have been seen; a herniation of the synovial membrane into the popliteal fossa and down the leg, and an acute synovial tear with extravasation of joint contents between the muscle planes of the calf. 3. The diagnosis of this condition, the differentiation of the types of rupture and their treatment are discussed. 4. The acute rupture usually responds to simple bed-rest; the large synovial herniations often need removal and repair of the posterior capsule

1. Out of 11,868 children born in one maternity department and examined neonatally three cases (possibly four) of typical dislocation were missed at the first examination but diagnosed and treated with good results within the following few months. 2. One single neonatal examination of the hip is not sufficient. Repeated examinations during the first weeks and months are essential. 3. Treatment with a Frejka pillow is unsatisfactory. The von Rosen splint is preferable. 4. Following the campaign for neonatal diagnosis and early treatment no case of established dislocation has been encountered after the age of six months. 5. Atypical cases present special problems

1 . A specific mechanism of injury can produce a tear of the articular disc of the wrist without any associated bony lesion. 2. Torn discs have been found associated with Colles's fractures and with dislocation of the inferior radio-ulnar joint. 3. The injury gives rise to clear-cut symptoms and definite physical signs. 4. Operation in fourteen cases has shown five types of tear of the disc. 5. Arthrographs of the wrist are helpful in establishing the diagnosis. 6. In isolated tears removal ofthe disc relieves the symptoms and does not prejudice function. 7. If there is other joint injury, removal of the disc cannot be expected to give as satisfactory a result

Aims

Periprosthetic joint infection (PJI) remains a challenging complication following total hip arthroplasty (THA). It is associated with high levels of morbidity, mortality and expense. Guidelines and protocols exist for the management of culture-positive patients. Managing culture-negative patients with a PJI poses a greater challenge to surgeons and the wider multidisciplinary team as clear guidance is lacking.

Aims

Positive cultures are not uncommon in cases of revision total knee and hip arthroplasty (TKA and THA) for presumed aseptic causes. The purpose of this study was to assess the incidence of positive intra-operative cultures in presumed aseptic revision of TKA and THA, and to determine whether the presence of intra-operative positive cultures results in inferior survival in such cases.

We studied the stability of cemented all-polyethylene keeled glenoid components by radiostereometric analysis (RSA) in 16 shoulders which had received a total shoulder replacement. There were 14 women (one bilateral) and one man with a mean age of 64 years. The diagnosis was osteoarthritis in eight and rheumatoid arthritis in seven. Two of the shoulders were excluded from the RSA study because of loosening of the tantalum markers. Three tantalum markers were inserted in the glenoid socket, two in the coracoid process and two in the acromion. The polyethylene keeled glenoid component was marked with three to five tantalum markers. Conventional radiological and RSA examinations were carried out at five to seven days, at four months and at one and two years after operation. Radiolucent lines were found in all except three shoulders. Migration was most pronounced in the distal direction and exceeded 1 mm in four shoulders. In ten shoulders rotation exceeded 2° in one or more axes with retroversion/anteversion being most common. No correlation was found between migration and the presence of radiolucencies on conventional radiographs

Aims

The primary aim of this study was to evaluate the performance and safety of magnetically controlled growth rods in the treatment of early onset scoliosis. Secondary aims were to evaluate the clinical outcome, the rate of further surgery, the rate of complications, and the durability of correction.

We report our results in 24 children with malignant primary bone tumours of the distal femur treated with a Stanmore extendible endoprosthesis (SEER). This consists of a femoral component that can be lengthened, a constrained knee and an uncemented sliding tibial component which crosses the proximal tibial physeal plate perpendicularly. The average age of the patients at diagnosis was ten years and the mean follow-up was 4.7 years (2.5 to 7.9). The mean growth of the affected tibia was 76% (18 to 136) and of the fibula 83% (15 to 750) of the growth of the unaffected limb. Measurement of growth arrest lines showed that the mean growth of the proximal tibial physis on the affected side was 69% (43 to 100) of that of the normal side. The great variability in the growth of the physis cannot yet be explained