A technique for performing allograft-augmented revision total knee replacement (TKR) using computer assistance is described, on the basis of the results in 14 patients. Bone deficits were made up with impaction grafting. Femoral grafting was made possible by the construction of a retaining wall or dam which allowed pressurisation and retention of the graft. Tibial grafting used a mixture of corticocancellous and morsellised allograft. The position of the implants was monitored by the computer system and adjusted while the cement was setting. The outcome was determined using a six-parameter, quantitative technique (the Perth CT protocol) which measured the alignment of the prosthesis and provided an objective score. The final outcomes were not perfect with errors being made in femoral rotation and in producing a mismatch between the femoral and tibial components. In spite of the shortcomings the alignments were comparable in accuracy with those after primary TKR. Computer assistance shows considerable promise in producing accurate alignment in revision TKR with bone deficits

Vascular malformations are rare congenital lesions which often have associated skeletal changes. Over a period of ten years, 90 patients at our clinic had a vascular anomaly of the lower limb, examined by either CT or MRI. Of these, 18 (20%) had bony involvement. A questionnaire was sent to these patients (8 men, 10 women) to evaluate their age of presentation, initial symptoms and current complaints. Radiological imaging revealed 15 low- and three high-flow lesions. The mean age at presentation to a physician was six years of age. Pain was the most common complaint. Disparity in leg length of 2 cm or more was observed in ten patients. Of the 16 patients with muscle infiltration, 13 had four or more muscles involved. Treatment by resection alone would require radical surgery

We have studied the case records of 16 patients with dislocations of the cervical spine who deteriorated neurologically during or after reduction. The dislocations were reduced by skull traction in four patients, by manipulation in four and by operation in seven. This complication was not related to age, sex, mechanism of injury, or the level and the type of dislocation. Fourteen patients made substantial recoveries, one made a partial recovery and one patient remained totally paralysed and died three months later. The causes and prevention of spinal-cord damage at this stage of management are discussed, and the early use of MRI or CT myelography is recommended

The action of fast bowling in the game of cricket is known to cause injuries to the lumbar spine. We studied a group of 16- to 18-year-old fast bowlers, selected for special training in Western Australia. All 24 had MR scans of the spine, 22 had radiographs and CT scans; in 20 the bowling technique was analysed biomechanically. There was a high incidence of back pain and this was always associated with a radiological abnormality. Pars interarticularis defects were diagnosed in 54% and intervertebral disc degeneration in 63%. Bowling actions which involved counter-rotation were associated with a higher incidence of both injuries

We report a case of systemic intraosseous lipomatosis involving the proximal femur, both ends of the tibia, and the tarsal and metatarsal bones. The lesions progressed during a five-year follow-up with a pathological fracture of the tibial plateau. CT scans were characteristic and helpful in diagnosis but MR imaging added little information. Intraosseous lipomatosis is a hamartomatous malformation due to hyperplasia of adipose tissue, and is fundamentally different from solitary benign intraosseous lipoma. Management involves reconstruction of any pathological fracture. Large progressive lesions should be treated by curettage and grafting in an attempt to prevent such fractures

Rupture of the tendons of both peroneus longus and peroneus brevis results in considerable disability. We have performed transfer of flexor digitorum longus (FDL) to peroneus brevis in two patients with lateral instability of the hindfoot due to chronic transverse tears of both tendons for which end-to-end repair was not possible. Both patients had excellent function when reviewed after eight and six years, respectively, with no symptoms. CT showed a normal appearance of the FDL in both patients, but the peroneal muscles looked abnormal. Transfer of the FDL provides a reliable solution to lateral instability of the hindfoot resulting from loss of function of both peronei

Aims

This paper documents the epidemiology of adults (aged more than 18 years) with a calcaneal fracture who have been admitted to hospital in England since 2000. Secondary aims were to document whether publication of the United Kingdom Heel Fracture Trial (UK HeFT) influenced the proportion of patients admitted to hospital with a calcaneal fracture who underwent surgical treatment, and to determine whether there has been any recent change in the surgical technique used for these injuries.

Hip arthrography was performed in 19 patients in the initial stage of Perthes' disease. Sphericity and subluxation were measured and it was found that subluxation was independent of the femoral head deformity. We therefore tried to identify the cause of early subluxation: in seven patients a swollen ligamentum teres was thought to be responsible, and was associated with medial pooling of the contrast medium. A swollen ligamentum teres was seen in another seven cases; the other five arthrograms were normal. These findings were further clarified by enhanced CT scans, which confirmed that ligament swelling may be an important cause of early subluxation

We performed single-photon-emission CT (SPECT) and planar bone scans to assess femoral head vascularity in ten patients with displaced intracapsular hip fracture. The heads were labelled with tetracycline and after excision at hemiarthroplasty were assessed for tetracycline uptake distribution by fluorescence under UV light. The four which had the greatest tetracycline uptake were normal on SPECT and planar imaging. In two cases the planar bone scans were normal although SPECT suggested avascularity thus giving false-negative results. Surgeons should be aware of this; SPECT may prove to be a more accurate method of assessing vascularity of the femoral head in fractures of the femoral neck

Our previous reports on the pathological anatomy and operative treatment of intra-articular fractures of the calcaneum failed to take account of the fracture pattern anterior to the posterior facet of the subtalar joint. We have reviewed our experience of 63 operative cases and have studied fractures with axial and coronal CT scans reconstructed onto plastic model bones. A constant anterolateral fragment exists, which is displaced by an extended lateral approach to the fracture. If it is unrecognised and unreduced, union in a displaced position may limit hindfoot eversion and disrupt the calcaneocuboid joint. We describe techniques for reduction and fixation of the fragment

The results of a cadaver dye-infusion experiment suggested that the hand has ten muscle compartments and that the volar interossei occupy a separate anatomical compartment from the adjacent dorsal interossei. This is not supported by clinical findings. With various minor modifications, we repeated the experiment, infusing Omnipaque into the second dorsal interosseus muscle of four cadaver hands. We used real-time CT imaging to monitor the spread of contrast medium and side-ported needles to measure compartmental pressures. In all four hands, the tissue barrier between dorsal and volar interossei became incompetent at pressures of less than 15 mmHg. Our data indicate that, although cadaver infusion studies can delineate potentially significant musculoskeletal barriers, their physiological relevance must be confirmed clinically

Degenerative spondylolisthesis is four times more common in women than in men. Although this gender difference has long been recognised there has been no explanation for it. We have examined the radiographs and CT scans of 118 patients over the age of 55 years and of a control group under the age of 46 years. Our findings confirmed the presence of more sagittally-orientated facet joints in patients with degenerative spondylolisthesis but did not show that the gender difference can be explained by the morphology of the facet joint. Furthermore, we conclude that the increased angle of the facet joint is the result of arthritic remodelling and not the primary cause of degenerative spondylolisthesis. It is more likely to be due to loss of soft-tissue resilience with subsequent failure of the facet joints which are acting as the last restraints to subluxation

Bone apatite contains carbonate and is therefore not pure hydroxyapatite. We have successfully developed sintered carbonate apatite (CA) with a concentration of carbonate of 6 weight% and have evaluated its osteoconductive and bioresorption characteristics. Cylindrical porous sintered CA and sintered hydroxyapatite (HA) measuring 4 × 4 mm with a porosity of 20% were implanted into surgically-created bone defects in the knees of rabbits. The animals were killed after 1, 3, 6 and 12 months. The defects were evaluated by microfocus CT and histology. Bone growth into and around both materials increased. Newly-formed bone was placed in direct contact with both. Osteoclast-like cells resorbed only CA, and were coupled with osteoblasts. The porosity of sintered CA increased, indicating bioresorption, whereas that of sintered HA did not increase. Our findings indicate that sintered CA may be useful as a bioresorbable bone substitute

Magnetic resonance imaging was performed on 28 patients with suspected calcaneal tendon injury prior to treatment. None of the patients were involved in competitive sports. All underwent clinical examination, some had had ultrasound or CT scans. We identified four types of lesions: type I, inflammatory reaction; type II, degenerative change; type III, incomplete rupture and type IV, complete rupture. Thirteen of the 28 patients underwent surgery and the diagnostic findings were verified. We recommend that type I, type II and type III lesions be managed conservatively, while type IV lesions should be operated in the young and active patient

Splitting fractures of the humeral head are rare; part of the humeral head dislocates and the unfractured part remains attached to the shaft. We report eight cases in young patients. In five the diagnosis was made at presentation: three had minimal internal fixation using a superior subacromial approach, one had a closed reduction and one a primary prosthetic replacement. All five patients regained excellent function with no avascular necrosis at two years. In three the injury was initially unrecognised; two developed a painless bony ankylosis and one is awaiting hemiarthroplasty. It is important to obtain the three trauma radiographic views to diagnose these unusual fractures reliably. CT delineates the configuration of the fracture. In young patients open reduction and internal fixation seems preferable to replacement of the humeral head, since we have shown that the head is potentially viable

We have studied 34 consecutive patients receiving Cotrel- Dubousset instrumentation for a single and flexible thoracic scoliotic curve, evaluating the rib hump deformity from a single CT scan through the apical vertebra of the curve. Using two measures of rotation we found a mean improvement of 25% in the rotation of the vertebra after operation. Any, usually minor, deterioration occurred in the first six months postoperatively, and there was no significant further deterioration in 19 patients assessed over two years after surgery. Cotrel-Dubousset instrumentation can produce a significant correction of vertebral rotation and of the associated rib hump deformity