1. The histories of 149 patients, coming to the Hospital for Sick Children within the first three years of life with congenital dislocation of the hip (191 dislocated hips), and treated by conservative methods, have been reviewed. 2. The patients with unilateral dislocations (107) have been divided into three groups, according to the angle of slope of the opposite acetabulum. This angle was measured on the first radiograph and related to the mean value for age and sex. 3. The opposite hip was classed as "normal" if the acetabular angle was below or within one standard deviation above the mean for sex and age; as "moderately shallow" if it was between one and two standard deviations above the mean; and as "shallow" if it was over two standard deviations above the mean. This grouping was found to have a direct bearing on the results of conservative treatment in unilateral cases. a) Those with "normal" opposite acetabula–accounting for most of the unilateral cases–responded well. b) Those with "moderately shallow" opposite acetabula responded variably. c) The group with "shallow" opposite acetabula usually failed to respond. 4. Most bilateral dislocations behaved as unilateral dislocations with shallow opposite hips. 5. Additional factors influencing the response to conservative treatment–sex, age at first attendance, family history, fragmentation of the femoral epiphysis and eccentric reduction–are discussed

Two acetabula which contained large bone allografts introduced at revision arthroplasty were obtained at post-mortem. The allografts had been placed in superior defects to support cementless acetabular components, and both hips were functioning well at the time of death. Clinical radiographs demonstrated apparent healing of graft to host bone, no graft collapse and stability of the acetabular components. Microscopic examination of sections through these specimens showed that the bulk allografts were encapsulated in fibrous tissue. Vascularity was increased at the host-graft interface, but there was limited evidence of bone union between the graft and the host. In the few areas where union had occurred, revascularisation extended no more than 2 mm beyond the graft-host interface. Within the body of the graft, the acellular matrix of trabecular bone maintained structural integrity up to 48 months after surgery. In areas where the allograft was adjacent to an implant, there was fibrous tissue orientated parallel to the implant surface. The acetabulum which contained a porous-coated component showed evidence of bone growth into the porous surface where it was in contact with viable host bone. No ingrowth occurred in areas where the porous coating was in contact with the graft. Although the grafts were functioning well, allograft revascularisation and remodelling were minimal, and the radiological appearance of healing did not correlate with histological findings

Aims

Vitamin E-diffused, highly crosslinked polyethylene (VEPE) and porous titanium-coated (PTC) shells were introduced in total hip arthroplasty (THA) to reduce the risk of aseptic loosening. The purpose of this study was: 1) to compare the wear properties of VEPE to moderately crosslinked polyethylene; 2) to assess the stability of PTC shells; and 3) to report their clinical outcomes at seven years.

Since wear and loosening of the ultra-high-molecular-weight polyethylene cup are factors which limit the life of an arthroplasty we have attempted to identify factors associated with either low wear (0.02 mm/year or less) or high wear (0.2 mm/year or more). In a series of 1434 Charnley low-friction arthroplasties (1092 patients) 190 (13.2%) showed low wear while 149 (10.4%) showed high wear. We used chi-squared test to assess the significance of various factors. The significant factors of the low-wear group were female gender (p = 0.042), rheumatoid arthritis (p = 0.014), Charnley grade C (p = 0.03) and varus position of the stem (p = 0.003). The use of acetabular cement pressurisation (p = 0.07) and medialisation of the cup (p = 0.07) approached significance. In the high-wear group there was a predominance of men (p = 0.042) with osteoarthritis (p = 0.006) as the underlying hip pathology, and the stem in a valgus position (p = 0.023). Support of the cup by the rim of the acetabulum approached significance (p = 0.07). There was no statistical significance between the two groups for revision for aseptic loosening of the stem or fracture of the stem (p = 0.49). There was a highly significant difference (p < 0.0001) between the two groups for revision for wear and aseptic loosening of the cup, 5.3% compared with 39%. Changes in the cup geometry are probably sufficient to explain the increasing incidence of loosening and revisions with the increasing depth of penetration of the cup. There is much to be gained from the use of a low-wearing ceramic-ultra-high-molecular-weight combination. Tissue reaction to the polyethylene particles cannot be the cause of aseptic loosening of the stem

Aims

A variety of surgical approaches are used for total hip arthroplasty (THA), all with reported advantages and disadvantages. A number of common complications can occur following THA regardless of the approach used. The purpose of this study was to compare five commonly used surgical approaches with respect to the incidence of surgery-related complications.

Aims

Studying the indications for revision total hip arthroplasty (THA) may enable surgeons to change their practice during the initial procedure, thereby reducing the need for revision surgery. The aim of this study was to identify and describe the potentially avoidable indications for revision THA within five years of the initial procedure.

Aims

The aim of this study was to evaluate the efficacy of the surgical dislocation approach and modified trapdoor procedure for the treatment of chondroblastoma of the femoral head.

Aims

This study presents the long-term survivorship, risk factors for prosthesis survival, and an assessment of the long-term effects of changes in surgical technique in a large series of patients treated by metal-on-metal (MoM) hip resurfacing arthroplasty (HRA).

A few points in this report deserve to be stressed. Indications–It is important that the orthopaedic surgeon should decide at a very early stage which of the two methods, closed or open, he must use. These do not exclude each other but are on the other hand complementary. Nowadays the dislocated hip can be reduced by open operation with a very good chance of lasting success. This should be carried out if a hip cannot easily be reduced otherwise, or if there is any doubt that closed reduction has been successful–and as early as possible, preferably before the age of three years. Technique–Ample exposure of the joint and removal of all obstacles to reduction are important. Reduction must be complete and stable but without stress, and there must be no interference with the articular bone and cartilage. After-care–Reduction, however perfect, is only the first step towards recovery. The hip must be observed carefully and the most suitable moments for mobilisation and for walking must be chosen; this calls for nice judgment. When it is clear that the roof of the acetabulum is not developing or that persistent valgus and anteversion may encourage subluxation, a secondary operation should be undertaken at once. Radiography is necessary about every three months for the first two years. Assessment of results–With a strict system of assessment, like McFarland's, we have observed 68·3 per cent favourable results in 171 hips treated by open reduction. It is obvious that the problem of congenital dislocation of the hip has not yet been completely solved. But if we review the progress of recent years we come to the encouraging conclusion that much has already been achieved, and that the efforts of the many orthopaedic surgeons who have dedicated themselves to the treatment of congenital dislocation of the hip have not gone unrewarded

We have reviewed 103 of 126 Chiari osteotomies carried out in our department between 1956 and 1987. The cases were graded radiologically, using the Japanese Orthopaedic Association (JOA) system, into a pre/early osteoarthritis (OA) group and an advanced OA group. In the pre/early group there were 86 hips. The mean follow-up was for 17.1 years (4 to 37). Preoperatively, 51 hips had an average JOA clinical score of 78.6 ± 8.4 points and the final mean JOA clinical score was 89.4 ± 12.5 points. Advanced degenerative change developed in 33.7% and one hip required a total replacement arthroplasty (TRA). Chiari osteotomy alone, without accompanying intertrochanteric osteotomy, was performed on 62 hips. For these the median survival time was 26.0 ± 2.5 years, using as the endpoint progression to advanced OA. Differences in survivorship curves related significantly to the severity of the preoperative OA, the shape of the femoral head and the level of osteotomy. In the advanced OA group, we followed up 17 hips for a mean of 16.2 years (1 to 27). Before operation, the mean JOA clinical score in 13 hips was 63.2 ± 7.9 points and the final score 84.0 ± 12.0 points. TRA was eventually carried out on four hips. Our findings suggest that the Chiari osteotomy remains radiologically effective for about 25 years. The procedure is best suited to subluxated hips with round or flat femoral heads and early or no degenerative change. Intra-articular osteotomy can lead to osteonecrosis, and should be avoided. In hips with advanced OA, the Chiari procedure creates an acetabulum which facilitates later TRA, and may delay the need for this procedure in younger patients

After open reduction for developmental dysplasia of the hip (DDH), a pelvic or femoral osteotomy may be required to maintain a stable concentric reduction. We report the clinical and radiological outcome in 82 children (95 hips) with DDH treated by open reduction through an anterior approach in which a test of stability was used to assess the need for a concomitant osteotomy. The mean age at the time of surgery was 28 months (9 to 79) and at the latest follow-up, 17 years (12 to 25). All patients have been followed up until closure of the triradiate cartilage with a mean period of 15 years (8 to 23). At the time of open reduction before closure of the joint capsule, the position of maximum stability was assessed. A hip which required flexion with abduction for stability was considered to need an innominate osteotomy. If only internal rotation and abduction were required, an upper femoral derotational and varus osteotomy was carried out. For a ‘double-diameter’ acetabulum with anterolateral deficiency, a Pemberton-type osteotomy was used. A hip which was stable in the neutral position required no concomitant osteotomy. Overall, 86% of the patients have had a satisfactory radiological outcome (Severin groups I and II) with an incidence of 7% of secondary procedures for persistent dysplasia including one hip which redislocated. The results were better (p = 0.04) in children under the age of two years. Increased leg length on the affected side was associated with poor acetabular development and recurrence of joint dysplasia (p = 0.01). The incidence of postoperative avascular necrosis was 7%. In a further 18%, premature physeal arrest was noted during the adolescent growth spurt (Kalamchi-MacEwen types II and III). Both of these complications were also associated with recurrence of joint dysplasia (p = 0.01). Studies with a shorter follow-up are therefore likely to underestimate the proportion of poor radiological results

Aims

The aim of this study was to examine the results of the acetabular distraction technique in achieving implantation of a stable construct, obtaining biological fixation, and producing healing of chronic pelvic discontinuity at revision total hip arthroplasty.

Aims

The hypothesis of this study was that thigh circumference, distinct from body mass index (BMI), may be associated with the positioning of components when undertaking total hip arthroplasty (THA) using the direct anterior approach (DAA), and that an increased circumference might increase the technical difficulty.

Aims

We previously reported the long-term results of the cementless Duraloc-Profile total hip arthroplasty (THA) system in a 12- to 15-year follow-up study. In this paper, we provide an update on the clinical and radiological results of a previously reported cohort of patients at 23 to 26 years´ follow-up.

Aims

Leucocyte esterase (LE) has been shown to be an accurate marker of prosthetic joint infection (PJI), and has been proposed as an alternative to frozen section (FS) histology for intraoperative diagnosis. In this study, the intraoperative assessment of LE was compared with FS histology for the diagnosis of prosthetic hip infection.

Aims

Displaced, comminuted acetabular fractures in the elderly are increasingly common, but there is no consensus on whether they should be treated non-surgically, surgically with open reduction and internal fixation (ORIF), or with acute total hip arthroplasty (THA). A combination of ORIF and acute THA, an approach called ’combined hip procedure’ (CHP), has been advocated and our aim was to compare the outcome after CHP or ORIF alone.