Patients who had a revision total hip arthroplasty using the Bürch-Schneider anti-protrusio cage (APC) by a single surgeon have been reviewed after a minimum of five years. There were 63 operations in 58 patients with an average age of 63 years (41 to 83) at the time of revision. At an average follow-up of 8.5 years (5 to 18), 15 patients (25.9%) rated their results as excellent, 38 (65.5%) as good, and five (8.6%) as fair. Five further revisions of the acetabular prosthesis were required, three due to aseptic loosening, one for recurrent dislocation and one due to sepsis. Of the remainder, one was definitely loose, two probably loose, and 12 possibly so. Impressive augmentation of bone stock can be achieved with the anti-protrusio cage, while enabling the hip to be centred in its anatomical position

A controlled study, comparing computer- and conventional jig-assisted total knee replacement in six cadavers is presented. In order to provide a quantitative assessment of the alignment of the replacements, a CT-based technique which measures seven parameters of alignment has been devised and used. In this a multi-slice CT machine scanned in 2.5 mm slices from the acetabular roof to the dome of the talus with the subject’s legs held in a standard position. The mechanical and anatomical axes were identified, from three-dimensional landmarks, in both anteroposterior and lateral planes. The coronal and sagittal alignment of the prosthesis was then measured against the axes. The rotation of the femoral component was measured relative to the transepicondylar axis. The rotation of the tibial component was measured with reference to the posterior tibial condyles and the tibial tuberosity. Coupled femorotibial rotational alignment was assessed by superimposition of the femoral and tibial axial images. The radiation dose was 2.7 mSV. The computer-assisted total knee replacements showed better alignment in rotation and flexion of the femoral component, the posterior slope of the tibial component and in the matching of the femoral and tibial components in rotation. Differences were statistically significant and of a magnitude that support extension of computer assistance to the clinical situation

We reviewed 28 patients with brachial plexus lesions caused by shoulder dislocation. Contrary to most other reports, we found that the neurological lesions involved the infraclavicular and the supraclavicular brachial plexus. With supraclavicular lesions the involvement was always of the suprascapular nerve, and this always recovered spontaneously. Isolated axillary nerve lesions had the poorest prognosis for spontaneous recovery. We explored all lesions that showed no recovery after three to five months and performed either grafting or neurolysis. We discuss the combinations of nerve lesions, their recovery, the surgical indications, and the operations. We also suggest a new classification for these injuries which is more clinically relevant than the anatomical classification of Leffert and Seddon (1965)

Aims

The routine use of dual-mobility (DM) acetabular components in total hip arthroplasty (THA) may not be cost-effective, but an increasing number of patients undergoing THA have a coexisting spinal disorder, which increases the risk of postoperative instability, and these patients may benefit from DM articulations. This study seeks to examine the cost-effectiveness of DM components as an alternative to standard articulations in these patients.

We examined the structure of the digital flexor sheath by dissection and histology. The inner aspect of the sheath was found not to be a continuous smooth surface, as depicted in anatomical and surgical texts. The thin parts of the sheath often overlapped the pulleys before attaching to their superficial aspects, so that the pulleys possessed free edges within the sheath. The frequency of occurrence and sizes of these overlaps were studied in 48 cadaveric fingers; the largest and most frequent overlap was at the distal end of the A2 pulley. Functional studies showed an intricate mechanism of pulley approximation and sheath bulging during flexion. Sutured or partly cut tendons triggered on the free edges; this could be a major contributor to the failures of tendon repairs in "no man's land"

Minor degrees of malalignment of the patella and anatomical abnormalities including a flattened sulcus angle and an increased ratio between patellar tendon length and patellar length (PT:P) have been suggested as predisposing factors in the causation of chondromalacia patellae, as well as patellar instability. In order to confirm or refute this hypothesis a prospective study has been performed comparing the congruence and sulcus angles and the PT:P ratio in a group of 35 patients with chondromalacia confirmed by arthroscopy and a group of 33 patients with instability, with those of a group of 50 knees in normal volunteers. While there was a statistically significant correlation between an increased sulcus and congruence angle and a high-riding patella in patients with instability, no correlation could be identified in patients with idiopathic chondromalacia

Clinical examinations and radiographic skeletal surveys have been carried out in 15 patients with foetal alcohol syndrome. Fusion of the capitate and hamate bones in the carpus was bilateral in one patient and unilateral in two. All three had accessory ossification centres at the proximal ends of both second metacarpals. Two of these patients also had radio-ulnar synostosis. Digital shortening, which was demonstrated by pattern profile analysis, was very variable in degree and anatomical distribution. Other skeletal changes of uncertain significance were a "beaten copper" appearance of the calvarium in four patients, and coxa valga in one other. Diagnosis of the foetal alcohol syndrome warrants consideration in any individual presenting with carpal fusion or with radio-ulnar synostosis

Ligamentous instability of the ankle joint can be confirmed by radiographs taken in two planes. The place of the anteroposterior varus stress view is established, but the lateral view which shows anterior subluxation of the talus is frequently omitted. The anatomical significance of the two stress views has been determined by dividing different components of the lateral ligament of 20 cadaveric ankles and noting the subluxation that resulted from these procedures. A clinical assessment was then made of 54 ankles (46 patients) with radiological evidence of instability when subjected to varus and anterior stress. Anterior subluxation was found to be considerably more common than varus tilt, and it is therefore suggested that the lateral stress view should be an essential part of the investigation of the unstable ankle

In order to investigate the functional anatomy of gluteus minimus we dissected 16 hips in fresh cadavers. The muscle originates from the external aspect of the ilium, between the anterior and inferior gluteal lines, and also at the sciatic notch from the inside of the pelvis where it protects the superior gluteal nerve and artery. It inserts anterosuperiorly into the capsule of the hip and continues to its main insertion on the greater trochanter. Based on these anatomical findings, a model was developed using plastic bones. A study of its mechanics showed that gluteus minimus acts as a flexor, an abductor and an internal or external rotator, depending on the position of the femur and which part of the muscle is active. It follows that one of its functions is to stabilise the head of the femur in the acetabulum by tightening the capsule and applying pressure on the head. Careful preservation or reattachment of the tendon of gluteus minimus during surgery on the hip is strongly recommended

A total of 60 children and adolescents with rupture of the anterior cruciate ligament (ACL) was seen between 1980 and 1990. Observation of the 23 patients who were treated conservatively revealed that the natural history of the injury resulted in severe instability and poor function of the knee. Associated meniscal tears were present in 15 knees. Three osteochondral fractures occurred and osteoarthritic changes developed in ten knees. In 1990 therefore we introduced reconstruction of the ACL with a four-strand hamstring graft using an anatomical placement with transphyseal tunnels and anchorage well away from the growth plate. Over a period of nine years, 47 knees underwent reconstruction. The mean follow-up was 49 months (12 to 96). No child suffered physeal damage or leg-length discrepancy. The results were satisfactory in 77% and there was little difference between patients treated before the adolescent growth spurt and those treated during or after this time. These results, however, were not as good as those seen in adults during the same period

We carried out 60 revision procedures for failed porous coated anatomic total knee replacements in 54 patients, which were divided into two groups. The 14 knees in group I had a well-fixed femoral component at surgery which was retained, and in the 46 knees in group II both tibial and femoral components were loose and were revised using a variety of implants. Our review comprised clinical and radiological assessment. A total of 13 knees required a second revision. Six (42%) in group I failed very early (mean 2.1 years) when compared with seven (15%) in group II (mean 6.8 years). Failure was due to wear of the polyethylene insert by the abraded, retained femoral component (crude odds ratio 4.07; 95% CI 1.07 to 15.5). We recommend a complete change of primary bearing surfaces at the time of revision of an uncemented total knee replacement in order to prevent early wear of polyethylene

Medial tibial plateaux excised during 46 unicompartmental arthroplasties for osteoarthritis were collected and photographed. The anterior cruciate ligament was intact in all joints. In every case the cartilage and bone erosion was centred anteriorly on the plateau and the posterior cartilage was intact. The site of the lesion and the intact state of the cruciate ligaments taken together explain why varus deformity was observed only in the extended knee, and why the deformity was correctable and had not become fixed. Failure of the anterior cruciate ligament may allow the erosion to extend posteriorly, producing fixed varus deformity and leading to degeneration of the lateral compartment. Anteromedial osteoarthritis is a distinct clinicopathological entity; its radiographic features enable it to be diagnosed from lateral radiographs; its anatomical features render it suitable for treatment by unicompartmental arthroplasty

We report a retrospective study of 54 acetabular fractures treated by open reduction and internal fixation, with an average follow-up of 9.6 years (3 to 17). Reduction leaving displacement of less than or equal to 2 mm was achieved in 36 hips (67%); good or excellent functional results were obtained in 33 patients (61%). Early complications requiring re-operation included postoperative loss of reduction in one case and an intra-articular screw in another. Arthrodesis or total hip arthroplasty had been performed in 10 patients (19%) who had late symptomatic degenerative changes. Failure to obtain accurate reduction was the most important factor leading to a poor result, but heterotopic calcification caused poor results in seven patients, five of whom had had an anatomical reduction

We report a retrospective study of 46 patients with continuing difficulties after anterior reconstruction of a shoulder for instability. In 31 patients instability was still present; in 12 of these, posterior or multidirectional instability had not been recognised and a further 11 had an uncorrected anatomical defect. In 20 patients with significant pain there was often more than one cause: impingement syndrome was seen in nine, osteoarthritis in seven, implant irritation in four and instability alone in two. A disabling medial rotation contracture was seen in 10 patients, four of whom had painful osteoarthritis. We conclude that recurrence of symptoms may imply that the direction of the instability was not recognised, that an anterior repair should not be too tight, and that pain after successful stabilisation is often due to impingement

From an anatomical study and clinical review of fractures of the lateral humeral condyle in children, the following conclusions are drawn. The mechanism of injury is a violent varus force with the elbow in extension, the condyle being avulsed. by the lateral ligament and the extensor muscles. If the fracture is incomplete, with an intact hinge of pre-osseous cartilage medially, the fragment will not be displaced. If the fracture is complete the fragment may be displaced, and open reduction with internal fixation is mandatory. The results of open reduction more than three weeks after the fracture are no better than those of no treatment at all, and may kill the lateral condylar fragment by damaging its blood supply. The major problem of a neglected fracture is tardy ulnar nerve palsy; to avoid this, immediate anterior transposition of the nerve is recommended, operation for the fracture itself being of no benefit

We describe a new technique, known as coregistration imaging, which superimposes . 99m. Tc isotope bone scans on to plain radiographs. We used the technique selectively in cases in which the nuclear medicine physician, who reported the isotope scan, had difficulty in localising the anatomical site of the abnormality. In the forefoot, coregistration of isotope scans did not help to localise pathology; the scan alone gave sufficient detail. In 17 patients with pain in the hind- and midfoot, isotope scanning identified eight sites of abnormality in those with normal radiographs. In those with more than one abnormality on plain radiographs the isotope scan eliminated 12 sites of suspicion. Coregistration of the images significantly increased the certainty of localisation of disease (p < 0.001). We recommend the selective use of coregistration scanning as a useful technique for investigating patients with pain in the foot and ankle

Biological fixation of cementless femoral implants requires primary stability by optimal fit in the proximal femur. The anatomy of the bone must then be known precisely. We analysed in vitro the accuracy of bone measurements of 32 femurs and compared the dimensions obtained from radiographs and CT scans with the true anatomical dimensions. Standard radiographs gave only a rough approximation of femoral geometry (mean difference: 2.4 +/- 1.4 mm) insufficiently accurate to allow selection of the best fitting prosthesis from a range of sizes and altogether inadequate to design a custom-made prosthesis. CT scans give greater accuracy (mean difference: 0.8 +/- 0.7 mm) in our experimental conditions, but in clinical practice additional sources of error exist

We compared the ability of three different posterior cruciate ligament (PCL) reconstructions to restore normal anteroposterior laxity to the knee from 0 to 130° of knee flexion. Cadaver knees were tested intact, after PCL rupture or after bone-patellar tendon-bone grafting. Grafts were performed isometrically or with a single bundle representing the anatomical anterior PCL fibre bulk (aPC) or with a double bundle that added the posterior PCL fibre bulk (pPC). The grafts were tensioned to restore normal knee laxity at 60° of flexion, except for the pPC which was tensioned at 130°. The isometric graft led to overconstraint as the knee extended resulting in high graft tension in extension and excess laxity in flexion. The aPC graft matched normal laxity from 0 to 60° of flexion but was lax from 90 to 130° of flexion. Only the double-bundled graft could restore normal knee laxity across the full range of flexion