Aims. This study aims to assess the relationship between history of pseudotumour formation secondary to metal-on-metal (MoM) implants and periprosthetic joint infection (PJI) rate, as well as establish ESR and CRP thresholds that are suggestive of infection in these patients. We hypothesized that patients with a pseudotumour were at increased risk of infection. Methods. A total of 1,171 total hip arthroplasty (THA) patients with MoM articulations from August 2000 to March 2014 were retrospectively identified. Of those, 328 patients underwent metal artefact reduction sequence MRI and had minimum two years’ clinical follow-up, and met our inclusion criteria. Data collected included demographic details, surgical indication, laterality, implants used, history of pseudotumour, and their corresponding preoperative ESR (mm/hr) and CRP (mg/dl) levels. Multivariate logistic regression modelling was used to evaluate PJI and history of pseudotumour, and receiver operating characteristic curves were created to assess the diagnostic capabilities of ESR and CRP to determine the presence of infection in patients undergoing revision surgery. Results. The rate of PJI for all identified MoM THAs was 3.5% (41/1,171), with a mean follow-up of 10.9 years (2.0 to 20.4). Of the patients included in the final cohort, 8.2% (27/328) had PJI, with a mean follow-up of 12.2 years (2.3 to 20.4). Among this cohort, 31.1% (102/328) had a history of pseudotumour. The rate of PJI in these patients was 14.7% (15/102), which was greater than those without pseudotumour, 5.3% (12/226) (p = 0.008). Additionally, logistic regression analysis showed an association between history of pseudotumour and PJI (odds ratio 4.36 (95% confidence interval 1.77 to 11.3); p = 0.002). Optimal diagnostic cutoffs for PJI in patients with history of pseudotumour versus those without were 33.1 mm/hr and 24.5 mm/hr for ESR and 7.37 mg/dl and 1.88 mg/dl for CRP, respectively. Conclusion. Patients with history of pseudotumour secondary to MoM THA had a higher likelihood of infection than those without. While suspicion of infection should be high for these patients, ESR and CRP cutoffs published by the European Bone and Joint Infection Society may not be appropriate for patients with a history of pseudotumour, as ESR and CRP levels suggestive of PJI are likely to be higher than for those without a pseudotumour. Additional investigation, such as aspiration, is highly recommended for these patients unless clinical suspicion and laboratory markers are low. Cite this article: Bone Joint J 2024;106-B(6):555–564

Aims. One-stage revision hip arthroplasty for periprosthetic joint infection (PJI) has several advantages; however, resection of the proximal femur might be necessary to achieve higher success rates. We investigated the risk factors for resection and re-revisions, and assessed complications and subsequent re-revisions. Methods. In this single-centre, case-control study, 57 patients who underwent one-stage revision arthroplasty for PJI of the hip and required resection of the proximal femur between 2009 and 2018 were identified. The control group consisted of 57 patients undergoing one-stage revision without bony resection. Logistic regression analysis was performed to identify any correlation with resection and the risk factors for re-revisions. Rates of all-causes re-revision, reinfection, and instability were compared between groups. Results. Patients who required resection of the proximal femur were found to have a higher all-cause re-revision rate (29.8% vs 10.5%; p = 0.018), largely due to reinfection (15.8% vs 0%; p = 0.003), and dislocation (8.8% vs 10.5%; p = 0.762), and showed higher rate of in-hospital wound haematoma requiring aspiration or evacuation (p = 0.013), and wound revision (p = 0.008). The use of of dual mobility components/constrained liner in the resection group was higher than that of controls (94.7% vs 36.8%; p < 0.001). The presence and removal of additional metal hardware (odds ratio (OR) = 7.2), a sinus tract (OR 4), ten years’ time interval between primary implantation and index infection (OR 3.3), and previous hip revision (OR 1.4) increased the risk of proximal femoral resection. A sinus tract (OR 9.2) and postoperative dislocation (OR 281.4) were associated with increased risk of subsequent re-revisions. Conclusion. Proximal femoral resection during one-stage revision hip arthroplasty for PJI may be required to reduce the risk of of recurrent or further infection. Patients with additional metalware needing removal or transcortical sinus tracts and chronic osteomyelitis are particularly at higher risk of needing proximal femoral excision. However, radical resection is associated with higher surgical complications and increased re-revision rates. The use of constrained acetabular liners and dual mobility components maintained an acceptable dislocation rate. These results, including identified risk factors, may aid in preoperative planning, patient consultation and consent, and intraoperative decision-making. Cite this article: Bone Joint J 2021;103-B(11):1678–1685

We have evaluated the effect of vacuum aspiration of the iliac wing on the osseointegration of cement into the acetabulum. We entered a total of 40 patients undergoing primary total hip arthroplasty into two consecutive study groups. Group 1 underwent acetabular cement pressurisation for 60 seconds before insertion of the acetabular component. Group 2 had the same pressurisation with simultaneous vacuum suction of the ilium using an iliac-wing aspirator. Standard post-operative radiographs were reviewed blindly to assess the penetration of cement into the iliac wing. Penetration was significantly greater in the group with aspiration of the iliac wing

Aims. Prosthetic joint infection (PJI) and aseptic loosening in total hip arthroplasty (THA) can present with pain and osteolysis. The Musculoskeletal Infection Society (MSIS) has provided criteria for the diagnosis of PJI. The aim of our study was to analyze the utility of F18-fluorodeoxyglucose (FDG) positron emission tomography (PET) CT scan in the preoperative diagnosis of septic loosening in THA, based on the current MSIS definition of prosthetic joint infection. Patients and Methods. A total of 130 painful unilateral cemented THAs with a mean follow-up of 5.17 years (. sd. 1.12) were included in this prospective study. The mean patient age was 67.5 years (. sd. 4.85). Preoperative evaluation with inflammatory markers, aspiration, and an F18 FDG PET scan were performed. Diagnostic utility tests were also performed, based on the MSIS criteria for PJI and three samples positive on culture alone. Results. The mean erythrocyte sedimentation rate, C-reactive protein, and white cell count were 47.83 mm/hr, 25.21 mg/l, and 11.05 × 10. 9. /l, respectively. The sensitivity, specificity, accuracy, negative predictive value, and false-positive rate of FDG PET compared with MSIS criteria were 94.87%, 38.46 %, 56.38%, 94.59 %, and 60.21%, respectively. The false-positive rate of FDG PET compared with culture alone was 77.4%. Conclusion. FDG PET has a definitive role in the preoperative evaluation of suspected PJI. This the first study to evaluate its utility based on MSIS criteria and compare it with microbiology results alone. However, FDG PET has a high false-positive rate. Therefore, we suggest that F18 FDG PET is useful in confirming the absence of infection, but if positive, may not be confirmatory of PJI. Cite this article: Bone Joint J 2019;101-B:910–914

Aims

Current diagnostic tools are not always able to effectively identify periprosthetic joint infections (PJIs). Recent studies suggest that circulating microRNAs (miRNAs) undergo changes under pathological conditions such as infection. The aim of this study was to analyze miRNA expression in hip arthroplasty PJI patients.

Aims

Two-stage exchange revision total hip arthroplasty (THA) performed in case of periprosthetic joint infection (PJI) has been considered for many years as being the gold standard for the treatment of chronic infection. However, over the past decade, there have been concerns about its safety and its effectiveness. The purposes of our study were to investigate our practice, collecting the overall spacer complications, and then to analyze their risk factors.

The aim of this study was to evaluate the ten-year clinical and functional outcome of hip resurfacing and to compare it with that of cementless hip arthroplasty in patients under the age of 55 years. . Between 1999 and 2002, 80 patients were enrolled into the study: 24 were randomised (11 to hip resurfacing, 13 to total hip arthroplasty), 18 refused hip resurfacing and chose cementless total hip arthroplasty with a 32 mm bearing, and 38 insisted on resurfacing. The mean follow-up for all patients was 12.1 years (10 to 14). Patients were assessed clinically and radiologically at one year, five years and ten years. Outcome measures included EuroQol EQ5D, Oxford, Harris hip, University of California Los Angeles and University College Hospital functional scores. . No differences were seen between the two groups in the Oxford or Harris hip scores or in the quality of life scores. Despite a similar aspiration to activity pre-operatively, a higher proportion of patients with a hip resurfacing were running and involved in sport and heavy manual labour after ten years. We found significantly higher function scores in patients who had undergone hip resurfacing than in those with a cementless hip arthroplasty at ten years. This suggests a functional advantage for hip resurfacing. There were no other attendant problems. Cite this article: Bone Joint J 2015; 97-B:617–22

Aims

Large acetabular bone defects encountered in revision total hip arthroplasty (THA) are challenging to restore. Metal constructs for structural support are combined with bone graft materials for restoration. Autograft is restricted due to limited volume, and allogenic grafts have downsides including cost, availability, and operative processing. Bone graft substitutes (BGS) are an attractive alternative if they can demonstrate positive remodelling. One potential product is a biphasic injectable mixture (Cerament) that combines a fast-resorbing material (calcium sulphate) with the highly osteoconductive material hydroxyapatite. This study reviews the application of this biomaterial in large acetabular defects.

Aims

Adult patients with history of childhood infection pose a surgical challenge for total hip arthroplasty (THA) due to distorted bony anatomy, soft-tissue contractures, risk of reinfection, and relatively younger age. Therefore, the purpose of the present study was to determine clinical outcome, reinfection rate, and complications in patients with septic sequelae after THA.

Aims

Femoral cement-in-cement revision is a well described technique to reduce morbidity and complications in hip revision surgery. Traditional techniques for septic revision of hip arthroplasty necessitate removal of all bone cement from the femur. In our two centres, we have been using a cement-in-cement technique, leaving the distal femoral bone cement in selected patients for septic hip revision surgery, both for single and the first of two-stage revision procedures. A prerequisite for adoption of this technique is that the surgeon considers the cement mantle to be intimately fixed to bone without an intervening membrane between cement and host bone. We aim to report our experience for this technique.

Aims

This study investigates the use of the metabolic equivalent of task (MET) score in a young hip arthroplasty population, and its ability to capture additional benefit beyond the ceiling effect of conventional patient-reported outcome measures.

Aims

There is a paucity of long-term studies analyzing risk factors for failure after single-stage revision for periprosthetic joint infection (PJI) following total hip arthroplasty (THA). We report the mid- to long-term septic and non-septic failure rate of single-stage revision for PJI after THA.

Aims

After failed acetabular fractures, total hip arthroplasty (THA) is a challenging procedure and considered the gold standard treatment. The complexity of the procedure depends on the fracture pattern and the initial fracture management. This study’s primary aim was to evaluate patient-reported outcome measures (PROMs) for patients who underwent delayed uncemented acetabular THA after acetabular fractures. The secondary aims were to assess the radiological outcome and the incidence of the associated complications in those patients.

We treated 50 consecutive patients with infected total hip arthroplasties according to a standard protocol. Previous surgery to eradicate the infection had been attempted in 13 patients and discharging sinuses were present in 20. Aspiration arthrography was routinely carried out before our interventions. The first stage was a meticulous removal of all foreign and potentially infected material. Samples were taken for culture and a thorough lavage carried out. Antibiotic-loaded beads were placed in the femoral shaft and an antibiotic-loaded cement ball in the acetabulum. At the second stage an uncemented arthroplasty was introduced. Bone allograft was used in 18 patients. The interval between procedures was usually three weeks, but this was extended if the wound was slow to heal or there was extensive bony destruction. Appropriate antibiotics were given for three months. At a mean follow-up of 5.8 years the rate of reinfection was 8% (4 patients). Two of these patients have had another, successful, two-stage revision. At this medium-term review, a satisfactory clinical and radiological outcome was obtained in all except two patients

Aims

The purpose of this study was to evaluate unexpected positive cultures in total hip arthroplasty (THA) revisions for presumed aseptic loosening, to assess the prevalence of low-grade infection using two definition criteria, and to analyze its impact on implant survival after revision.

Aims

We aimed to report the mid- to long-term rates of septic and aseptic failure after two-stage revision surgery for periprosthetic joint infection (PJI) following total hip arthroplasty (THA).

Aims

We studied the safety and efficacy of multimodal thromboprophylaxis in patients with a history of venous thromboembolism (VTE) who undergo total hip arthroplasty (THA) within the first 120 postoperative days, and the mortality during the first year. Multimodal prophylaxis includes discontinuation of procoagulant medications, VTE risk stratification, regional anaesthesia, an intravenous bolus of unfractionated heparin prior to femoral preparation, rapid mobilization, the use of pneumatic compression devices, and chemoprophylaxis tailored to the patient’s risk of VTE.

Aims

The increasing infection burden after total hip arthroplasty (THA) has seen a rise in the use of two-stage exchange arthroplasty and the use of increasingly powerful antibiotics at the time of this procedure. As a result, there has been an increase in the number of failed two-stage revisions during the past decade. The aim of this study was to clarify the outcome of repeat two-stage revision THA following a failed two-stage exchange due to recurrent prosthetic joint infection (PJI).

Aims

The present study investigated the five-year interval changes in pseudotumours and measured serum metal ions at long-term follow-up of a previous report of 28 mm diameter metal-on-metal (MoM) total hip arthroplasty (THA).

Aims

Single-stage revision is not widely pursued due to restrictive inclusion criteria. In this study, we evaluated the results of single-stage revision of chronically infected total hip arthroplasty (THA) using broad inclusion criteria and cementless implants.

Aims

Recurrent infection following two-stage revision total hip arthroplasty (THA) for prosthetic joint infection (PJI) is a devastating complication. The purpose of this study was to report the survival of repeat two-stage revision hip arthroplasty, describe complications, and identify risk factors for failure.

Aims

The aims of this study were to characterize antibiotic choices for perioperative total knee arthroplasty (TKA) and total hip arthroplasty (THA) prophylaxis, assess antibiotic allergy testing efficacy, and determine rates of prosthetic joint infection (PJI) based on perioperative antibiotic regimen.

Aims

To report our experience with trunnion corrosion following metal-on-polyethylene total hip arthroplasty, in particular to report the spectrum of presentation and determine the mean time to presentation.

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.

Objectives

Our primary aim was to describe migration of the Exeter stem with a 32 mm head on highly crosslinked polyethylene and whether this is influenced by age. Our secondary aims were to assess functional outcome, satisfaction, activity, and bone mineral density (BMD) according to age.

Aims

Fretting and corrosion at the modular head/neck junction, known as trunnionosis, in total hip arthroplasty (THA) is a cause of adverse reaction to metal debris (ARMD). We describe the outcome of revision of metal-on-polyethylene (MoP) THA for ARMD due to trunnionosis with emphasis on the risk of major complications.

Aims

We hypothesised that the synovial white blood cell (WBC) count in patients with a late periprosthetic joint infection (PJI) of the hip would depend on the duration of a patient’s symptoms, and that the optimal diagnostic threshold would also depend on this period of time.

Patients with neuromuscular imbalance who require total hip arthroplasty (THA) present particular technical problems due to altered anatomy, abnormal bone stock, muscular imbalance and problems of rehabilitation.

In this systematic review, we studied articles dealing with THA in patients with neuromuscular imbalance, published before April 2017. We recorded the demographics of the patients and the type of neuromuscular pathology, the indication for surgery, surgical approach, concomitant soft-tissue releases, the type of implant and bearing, pain and functional outcome as well as complications and survival.

Recent advances in THA technology allow for successful outcomes in these patients. Our review suggests excellent benefits for pain relief and good functional outcome might be expected with a modest risk of complication.

Cite this article: Bone Joint J 2018;100-B(1 Supple A):17–21.

Objectives

The diagnosis of periprosthetic joint infection (PJI) is difficult and requires a battery of tests and clinical findings. The purpose of this review is to summarize all current evidence for common and new serum biomarkers utilized in the diagnosis of PJI.

Aims

Using a systematic review, we investigated whether there is an increased risk of post-operative infection in patients who have received an intra-articular corticosteroid injection to the hip for osteoarthritis prior to total hip arthroplasty (THA).

Aims

The purpose of this study was to validate the diagnosis of periprosthetic joint infection (PJI) in the Danish Hip Arthroplasty Register (DHR).

Aims

There are many guidelines that help direct the management of patients with metal-on-metal (MOM) hip arthroplasties. We have undertaken a study to compare the management of patients with MOM hip arthroplasties in different countries.

Aims

We present a case series of ten metal-on-polyethylene total hip arthroplasties (MoP THAs) with delayed dislocation associated with unrecognised adverse local tissue reaction due to corrosion at the trunnion and pseudotumour formation.

Based on the first implementation of mixing antibiotics into bone cement in the 1970s, the Endo-Klinik has used one stage exchange for prosthetic joint infection (PJI) in over 85% of cases. Looking carefully at current literature and guidelines for PJI treatment, there is no clear evidence that a two stage procedure has a higher success rate than a one-stage approach. A cemented one-stage exchange potentially offers certain advantages, mainly based on the need for only one operative procedure, reduced antibiotics and hospitalisation time. In order to fulfill a one-stage approach, there are obligatory pre-, peri- and post-operative details that need to be meticulously respected, and are described in detail. Essential pre-operative diagnostic testing is based on the joint aspiration with an exact identification of any bacteria. The presence of a positive bacterial culture and respective antibiogram are essential, to specify the antibiotics to be loaded to the bone cement, which allows a high local antibiotic elution directly at the surgical side. A specific antibiotic treatment plan is generated by a microbiologist. The surgical success relies on the complete removal of all pre-existing hardware, including cement and restrictors and an aggressive and complete debridement of any infected soft tissues and bone material. Post-operative systemic antibiotic administration is usually completed after only ten to 14 days.

Cite this article: Bone Joint J 2013;95-B, Supple A:77–83.

Acetabular bone loss is a challenging problem facing the revision total hip replacement surgeon. Reconstruction of the acetabulum depends on the presence of anterosuperior and posteroinferior pelvic column support for component fixation and stability. The Paprosky classification is most commonly used when determining the location and degree of acetabular bone loss. Augments serve the function of either providing primary construct stability or supplementary fixation.

When a pelvic discontinuity is encountered we advocate the use of an acetabular distraction technique with a jumbo cup and modular porous metal acetabular augments for the treatment of severe acetabular bone loss and associated chronic pelvic discontinuity.

Cite this article: Bone Joint J 2014;96-B(11 Suppl A):36–42.

We describe our technique and rationale using hybrid fixation for primary total hip arthroplasty (THA) at the Hospital for Special Surgery. Modern uncemented acetabular components have few screw holes, or no holes, polished inner surfaces, improved locking mechanisms, and maximised thickness and shell-liner conformity. Uncemented sockets can be combined with highly cross-linked polyethylene liners, which have demonstrated very low wear and osteolysis rates after ten to 15 years of implantation. The results of cement fixation with a smooth or polished surface finished stem have been excellent, virtually eliminating complications seen with cementless fixation like peri-operative femoral fractures and thigh pain. Although mid-term results of modern cementless stems are encouraging, the long-term data do not show reduced revision rates for cementless stems compared with cemented smooth stems. In this paper we review the conduct of a hybrid THA, with emphasis on pre-operative planning, surgical technique, hypotensive epidural anaesthesia, and intra-operative physiology.

Cite this article: Bone Joint J 2016;98-B(1 Suppl A):54–9.

A moderator and panel of five experts led an interactive session in discussing five challenging and interesting patient case presentations involving surgery of the hip. The hip pathologies reviewed included failed open reduction internal fixation of subcapital femoral neck fracture, bilateral hip disease, evaluation of pain after metal-on-metal hip arthroplasty, avascular necrosis, aseptic loosening secondary to osteolysis and polyethylene wear, and management of ceramic femoral head fracture.

Hip replacement is a very successful operation and the outcome is usually excellent. There are recognised complications that seem increasingly to give rise to litigation. This paper briefly examines some common scenarios where litigation may be pursued against hip surgeons. With appropriate record keeping, consenting and surgical care, the claim can be successfully defended if not avoided. We hope this short summary will help to highlight some common pitfalls. There is extensive literature available for detailed study.

Fracture of a ceramic component in total hip replacement is a rare but potentially catastrophic complication. The incidence is likely to increase as the use of ceramics becomes more widespread. We describe such a case, which illustrates how inadequate initial management will lead to further morbidity and require additional surgery. We present the case as a warning that fracture of a ceramic component should be revised to another ceramic-on-ceramic articulation in order to minimise the risk of further catastrophic wear.

We present a series of 114 patients with microbiologically-proven chronically-infected total hip replacement, treated between 1991 and 2004 by a two-stage exchange procedure with antibiotic-loaded cement, but without the use of a prolonged course of antibiotic therapy. The mean follow-up for all patients was 74 months (2 to 175) with all surviving patients having a minimum follow-up of two years. Infection was successfully eradicated in 100 patients (87.7%), a rate which is similar to that reported by others, but where prolonged adjuvant antibiotic therapy has been used. Using the technique described, a prolonged course of systemic antibiotics does not appear to be essential and the high cost of the administration of antibiotics can be avoided.

The peri-prosthetic tissue response to wear debris is complex and influenced by various factors including the size, area and number of particles. We hypothesised that the ‘biologically active area’ of all metal wear particles may predict the type of peri-prosthetic tissue response.

Peri-prosthetic tissue was sampled from 21 patients undergoing revision of a small diameter metal-on-metal (MoM) total hip arthroplasty (THA) for aseptic loosening. An enzymatic protocol was used for tissue digestion and scanning electron microscope was used to characterise particles. Equivalent circle diameters and particle areas were calculated. Histomorphometric analyses were performed on all tissue specimens. Aspirates of synovial fluid were collected for analysis of the cytokine profile analysis, and compared with a control group of patients undergoing primary THA (n = 11) and revision of a failed ceramic-on-polyethylene arthroplasty (n = 6).

The overall distribution of the size and area of the particles in both lymphocyte and non-lymphocyte-dominated responses were similar; however, the subgroup with lymphocyte-dominated peri-prosthetic tissue responses had a significantly larger total number of particles.

14 cytokines (interleukin (IL)-1ß, IL-2, IL-4, IL-5, IL-6, IL-10, IL-13, IL-17, interferon (IFN)-γ, and IFN-gamma-inducible protein 10), chemokines (macrophage inflammatory protein (MIP)-1α and MIP-1ß), and growth factors (granulocyte macrophage colony stimulating factor (GM-CSF) and platelet derived growth factor) were detected at significantly higher levels in patients with metal wear debris compared with the control group.

Significantly higher levels for IL-1ß, IL-5, IL-10 and GM-CSF were found in the subgroup of tissues from failed MoM THAs with a lymphocyte-dominated peri-prosthetic response compared with those without this response.

These results suggest that the ‘biologically active area’ predicts the type of peri-prosthetic tissue response. The cytokines IL-1ß, IL-5, IL-10, and GM-CSF are associated with lymphocyte-dominated tissue responses from failed small-diameter MoM THA.

Cite this article: Bone Joint J 2015;97-B:917–23.

The aim of this study was to assess the role of synovial C-reactive protein (CRP) in the diagnosis of chronic periprosthetic hip infection. We prospectively collected synovial fluid from 89 patients undergoing revision hip arthroplasty and measured synovial CRP, serum CRP, erythrocyte sedimentation rate (ESR), synovial white blood cell (WBC) count and synovial percentages of polymorphonuclear neutrophils (PMN). Patients were classified as septic or aseptic by means of clinical, microbiological, serum and synovial fluid findings. The high viscosity of the synovial fluid precluded the analyses in nine patients permitting the results in 80 patients to be studied. There was a significant difference in synovial CRP levels between the septic (n = 21) and the aseptic (n = 59) cohort. According to the receiver operating characteristic curve, a synovial CRP threshold of 2.5 mg/l had a sensitivity of 95.5% and specificity of 93.3%. The area under the curve was 0.96. Compared with serum CRP and ESR, synovial CRP showed a high diagnostic value. According to these preliminary results, synovial CRP may be a useful parameter in diagnosing chronic periprosthetic hip infection.

Cite this article: Bone Joint J 2015; 97-B:173–6.

We report the five year outcomes of a two-stage approach for infected total hip replacement. This is a single-surgeon experience at a tertiary centre where the more straightforward cases are treated using single-stage exchange. This study highlights the vital role of the multidisciplinary team in managing these cases.

A total of 125 patients (51 male, 74 female) with a mean age of 68 years (42 to 78) were reviewed prospectively. Functional status was assessed using the Harris hip score (HHS). The mean HHS improved from 38 (6 to 78.5) pre-operatively to 81.2 (33 to 98) post-operatively. Staphylococcus species were isolated in 85 patients (68%).

The rate of control of infection was 96% at five years. In all, 19 patients died during the period of the study. This represented a one year mortality of 0.8% and an overall mortality of 15.2% at five years. No patients were lost to follow-up.

We report excellent control of infection in a series of complex patients and infections using a two-stage revision protocol supported by a multidisciplinary approach. The reason for the high rate of mortality in these patients is not known.

Cite this article: Bone Joint J 2014;96-B:1312–18

Plasma levels of cobalt and chromium ions and Metal Artefact Reduction Sequence (MARS)-MRI scans were performed on patients with 209 consecutive, unilateral, symptomatic metal-on-metal (MoM) hip arthroplasties. There was wide variation in plasma cobalt and chromium levels, and MARS-MRI scans were positive for adverse reaction to metal debris (ARMD) in 84 hips (40%). There was a significant difference in the median plasma cobalt and chromium levels between those with positive and negative MARS-MRI scans (p < 0.001). Compared with MARS-MRI as the potential reference standard for the diagnosis of ARMD, the sensitivity of metal ion analysis for cobalt or chromium with a cut-off of > 7 µg/l was 57%. The specificity was 65%, positive predictive value was 52% and the negative predictive value was 69% in symptomatic patients. A lowered threshold of > 3.5 µg/l for cobalt and chromium ion levels improved the sensitivity and negative predictive value to 86% and 74% but at the expense of specificity (27%) and positive predictive value (44%).

Metal ion analysis is not recommended as a sole indirect screening test in the surveillance of symptomatic patients with a MoM arthroplasty. The investigating clinicians should have a low threshold for obtaining cross-sectional imaging in these patients, even in the presence of low plasma metal ion levels.

Persistent groin pain after seemingly successful total hip replacement (THR) appears to have become more common. Recent studies have indicated a high incidence after metal-on-polyethylene and metal-on-metal conventional THR and it has been documented in up to 18% of patients after metal-on-metal resurfacing. There are many causes, including acetabular loosening, stress fracture, and iliopsoas tendonitis and impingement. The evaluation of this problem requires a careful history and examination, plain radiographs and an algorithmic approach to special diagnostic imaging and tests. Non-operative treatment is not usually successful. Specific operative treatment depending on the cause of the pain usually involves revision of the acetabular component, iliopsoas tenotomy or other procedures, and is usually successful. Here, an appropriate algorithm is described.

Total hip replacement (THR) still is a rare intervention in many African countries. In Burkina Faso it is not performed on a regular basis. A visiting programme for THR was started in a district hospital with no previous relevant experience. In this paper we present an analysis of the surgical technical problems and peri-operative complications of 152 THRs in 136 patients and three bipolar hemiarthroplasties in three patients undertaken in this new programme with limited orthopaedic equipment. There were 86 male and 53 female patients with a mean age of 49 years (21 to 78). We identified 77 intra-operative technical problems in 51 operations. There were 24 peri-operative complications in 21 patients, 17 of which were bony in nature. So far, ten revision THRs have been performed in nine patients.

Regular analysis of the technical problems and complications was used to improve quality, and we identified patient selection adapted to the local circumstances as important to avoid complications. Our reflections on the problems encountered in initiating such a programme may be of help to other teams planning similar projects.

Cite this article: Bone Joint J 2014;96-B:177–80.

Total hip replacement (THR) after acetabular fracture presents unique challenges to the orthopaedic surgeon. The majority of patients can be treated with a standard THR, resulting in a very reasonable outcome. Technical challenges however include infection, residual pelvic deformity, acetabular bone loss with ununited fractures, osteonecrosis of bone fragments, retained metalwork, heterotopic ossification, dealing with the sciatic nerve, and the difficulties of obtaining long-term acetabular component fixation. Indications for an acute THR include young patients with both femoral head and acetabular involvement with severe comminution that cannot be reconstructed, and the elderly, with severe bony comminution. The outcomes of THR for established post-traumatic arthritis include excellent pain relief and functional improvements. The use of modern implants and alternative bearing surfaces should improve outcomes further.

Cite this article: Bone Joint J 2013;95-B, Supple A:11–16.

Periprosthetic infection following total hip replacement can be a catastrophic complication for the patient. The treatments available include single-stage exchange, and two-stage exchange. We present a series of 50 consecutive patients with a diagnosis of infected total hip replacement who were assessed according to a standardised protocol. Of these, 11 underwent single-stage revision arthroplasty with no recurrence of infection at a mean of 6.8 years follow-up (5.5 to 8.8). The remaining 39 underwent two-stage revision, with two recurrences of infection successfully treated by a second two-stage procedure. At five years, significant differences were found in the mean Harris Hip Scores (single-stage 87.8; two-stage 75.5; p = 0.0003) and in a visual analogue score for satisfaction (8.6; 6.9; p = 0.001) between the single- and two-stage groups. Single-stage exchange is successful in eradicating periprosthetic infection and results in excellent functional and satisfaction scores.

Identification of patients suitable for the single-stage procedure allows individualisation of care and provides as many as possible with the correct strategy in successfully tackling their periprosthetic infection

We retrospectively analysed concentrations of chromium and cobalt ions in samples of synovial fluid and whole blood taken from a group of 92 patients with failed current-generation metal-on-metal hip replacements. We applied acid oxidative digestion to our trace metal analysis protocol, which found significantly higher levels of metal ion concentrations in blood and synovial fluid than a non-digestive method. Patients were subcategorised by mode of failure as either ‘unexplained pain’ or ‘defined causes’. Using this classification, chromium and cobalt ion levels were present over a wider range in synovial fluid and not as strongly correlated with blood ion levels as previously reported. There was no significant difference between metal ion concentrations and manufacturer of the implant, nor femoral head size below or above 50 mm. There was a moderately positive correlation between metal ion levels and acetabular component inclination angle as measured on three-dimensional CT imaging.

Our results suggest that acid digestion of samples of synovial fluid samples is necessary to determine metal ion concentrations accurately so that meaningful comparisons can be made between studies.

Between December 2004 and June 2006, 136 patients (156 total hip replacements), were sent from the waiting list of the Cardiff Vale NHS Trust to the NHS Treatment Centre, Weston-super-Mare, in an attempt to reduce the waiting time for total hip replacement. Because of concerns about their outcome, each patient was contacted and invited to attend a review appointment with a consultant specialising in hip and revision hip replacement.

A total of 98 patients (113 hips) were reviewed after a mean of 23 months (11 to 30). There were 104 cemented hips, seven hybrid and two cementless. An acetabular inclination of > 55° was seen in 18 (16%). Radiolucent lines around the acetabular component were seen in 76 (67%). The femoral component was in more than 4° of varus in 47 (42%). The medial floor had been breached in 13 (12%) and there was a leg-length discrepancy of more than 1 cm in ten (9%). There were three dislocations, one femoral fracture, one pulmonary embolus, one deep infection and two superficial wound infections.

To date, 13% (15 hips) have been revised and a further 4% (five hips) await revision, mostly for a painful loose acetabular component. The revision rate far exceeds the 0.5% five-year failure rate reported in the Swedish Registry for the components used. This initiative and the consequent need for correction of the problems created, has significantly increased the workload of our unit.