In this study of 41 patients, we used proteomic, Western blot and immunohistochemical analyses to show that several reactive oxygen species scavenging enzymes are expressed differentially in patients with primary osteoarthritis and those with non-loosening and aseptic loosening after total hip replacement (THR). The patients were grouped as A (n = 16, primary THR), B (n = 10, fixed THR but requiring revision for polyethylene wear) and C (n = 15, requiring revision due to aseptic loosening) to verify the involvement of the identified targets in aseptic loosening. When compared with Groups A and B, Group C patients exhibited significant up-regulation of transthyretin and superoxide dismutase 3, but down-regulation of glutathione peroxidase 2 in their hip synovial fluids. Also, higher levels of superoxide dismutase 2 and peroxiredoxin 2, but not superoxide dismutase 1, catalase and glutathione perioxidase 1, were consistently detected in the hip capsules of Group C patients.

We propose that dysregulated reactive oxygen species-related enzymes may play an important role in the pathogenesis and progression of aseptic loosening after THR.

Juvenile idiopathic arthritis (JIA) is a chronic disease of childhood; it causes joint damage which may require surgical intervention, often in the young adult. The aim of this study was to describe the long-term outcome and survival of hip replacement in a group of adult patients with JIA and to determine predictors of survival for the prosthesis. In this retrospective comparative study patients were identified from the database of a regional specialist adult JIA clinic. This documented a series of 47 hip replacements performed in 25 adult patients with JIA. Surgery was performed at a mean age of 27 years (11 to 47), with a mean follow-up of 19 years (2 to 36). The mean Western Ontario and McMaster Universities osteoarthritis index questionnaire (WOMAC) score at the last follow-up was 53 (19 to 96) and the mean Health Assessment Questionnaire score was 2.25 (0 to 3). The mean pain component of the WOMAC score (60 (20 to 100)) was significantly higher than the mean functional component score (46 (0 to 97)) (p = 0.02). Kaplan-Meier survival analysis revealed a survival probability of 46.6% (95% confidence interval 37.5 to 55.7) at 19 years, with a trend towards enhanced survival with the use of a cemented acetabular component and a cementless femoral component. This was not, however, statistically significant (acetabular component, p = 0.76, femoral component, p = 0.45). Cox’s proportional hazards regression analysis showed an implant survival rate of 54.9% at 19 years at the mean of covariates.

Survival of the prosthesis was significantly poorer (p = 0.001) in patients who had been taking long-term corticosteroids and significantly better (p = 0.02) in patients on methotrexate.

We conducted a retrospective study to investigate the effect of femoral bowing on the placement of components in total knee replacement (TKR), with regard to its effect on reestablishing the correct mechanical axis, as we hypothesised that computer-assisted total knee replacement (CAS-TKR) would produce more accurate alignment than conventional TKR. Between January 2006 and December 2009, 212 patients (306 knees) underwent TKR. The conventional TKR was compared with CAS-TKR for accuracy of placement of the components and post-operative alignment, as determined by five radiological measurements. There were significant differences in the reconstructed mechanical axes between the bowed and the non-bowed group after conventional TKR (176.2° (sd 3.4) vs 179.3° (sd 2.1), p < 0.001).

For patients with significant femoral bowing, the reconstructed mechanical axes were significantly closer to normal in the CAS group than in the conventional group (179.2° (sd 1.9) vs 176.2° (sd 3.4), p < 0.001). Femoral bowing resulted in inaccuracy when a conventional technique was used. CAS-TKR provides an effective method of restoring the mechanical axis in the presence of significant femoral bowing.

In a time of limited resources, the debate continues over which types of hip prosthesis are clinically superior and more cost-effective. Orthopaedic surgeons increasingly need robust economic evidence to understand the full value of the operation, and to aid decision making on the ‘package’ of procedures that are available and to justify their practice beyond traditional clinical preference.

In this paper we explore the current economic debate about the merits of cemented and cementless total hip replacement, an issue that continues to divide the orthopaedic community.

Cite this article: Bone Joint J 2013;95-B:874–6.

There have been comparatively few studies of the incidence of osteolysis and the survival of hybrid and cementless total hip replacements (THRs) in patients younger than 50 years of age. We prospectively reviewed 78 patients (109 hips) with a hybrid THR having a mean age of 43.4 years (21 to 50) and 79 patients (110 hips) with a cementless THR with a mean age of 46.8 years (21 to 49). The patients were evaluated clinically using the Harris hip score, the Western Ontario and McMaster Universities (WOMAC) osteoarthritis score and the University of California, Los Angeles (UCLA) activity score. Radiographs and CT scans were assessed for loosening and osteolysis. The mean follow-up was for 18.4 years (16 to 19) in both groups.

The mean post-operative Harris hip scores (91 points versus 90 points), the mean WOMAC scores (11 points versus 13 points) and UCLA activity scores (6.9 points versus 7.1 points) were similar in both groups. The revision rates of the acetabular component (13% versus 16%) and the femoral component (3% versus 4%), and the survival of the acetabular component (87% versus 84%) and the femoral component (97% versus 96%) were similar in both groups.

Although the long-term fixation of the acetabular metallic shell and the cemented and cementless femoral components was outstanding, wear and peri-acetabular osteolysis constitute the major challenges of THR in young patients.

We reviewed 123 second-generation uncemented total hip replacements performed on 115 patients by a single surgeon between 1993 and 1994. The acetabular component used in all cases was a fully porous-coated threaded hemispheric titanium shell (T-Tap ST) with a calcium ion stearate-free, isostatically compression-moulded polyethylene liner. The titanium femoral component used was a Taperloc with a reduced distal stem. No patient was lost to follow-up. Complete clinical and radiological follow-up was obtained for all 123 hips at a mean of 14 years (12 to 16). One femoral component was revised after a fracture, and three acetabular components for aseptic loosening. No additional femoral or acetabular components were judged loose by radiological criteria. Mild proximal femoral osteolysis was identified in two hips and minor acetabular osteolysis was present in four. The mean rate of penetration of the femoral head was 0.036 mm/year (0.000 to 0.227).

These findings suggest that refinements in component design may be associated with excellent long-term fixation in cementless primary total hip replacement.

Iontophoresis is a novel technique which may be used to facilitate the movement of antibiotics into the substance of bone using an electrical potential applied externally. We have examined the rate of early infection in allografts following application of this technique in clinical practice. A total of 31 patients undergoing revision arthroplasty or surgery for limb salvage received 34 iontophoresed sequential allografts, of which 26 survived for a minimum of two years. The mean serum antibiotic levels after operation were low (gentamicin 0.37 mg/l (0.2 to 0.5); flucloxacillin 1 mg/l (0 to 1) and the levels in the drains were high (gentamicin 40 mg/l (2.5 to 131); flucloxacillin 17 mg/l (1 to 43). There were no early deep infections. Two late infections were presumed to be haemotogenous; 28 of the 34 allografts were retained. In 12 patients with pre-existing proven infection further infection has not occurred at a mean follow-up of 51 months (24 to 82).

In an initial randomised controlled trial (RCT) we segregated 180 patients to one of two knee positions following total knee replacement (TKR): six hours of knee flexion using either a jig or knee extension. Outcome measures included post-operative blood loss, fall in haemoglobin, blood transfusion requirements, knee range of movement, limb swelling and functional scores. A second RCT consisted of 420 TKR patients randomised to one of three post-operative knee positions: flexion for three or six hours post-operatively, or knee extension.

Positioning of the knee in flexion for six hours immediately after surgery significantly reduced blood loss (p = 0.002). There were no significant differences in post-operative range of movement, swelling, pain or outcome scores between the various knee positions in either study. Post-operative knee flexion may offer a simple and cost-effective way to reduce blood loss and transfusion requirements following TKR.

We also report a cautionary note regarding the potential risks of prolonged knee flexion for more than six hours observed during clinical practice in the intervening period between the two trials, with 14 of 289 patients (4.7%) reporting lower limb sensory neuropathy at their three-month review.

Cite this article: Bone Joint J 2014;96-B:201–9.

Total hip replacement (THR) has been shown to be a cost-effective procedure. However, it is not risk-free. Certain conditions, such as diabetes mellitus, are thought to increase the risk of complications. In this study we have evaluated the prevalence of diabetes mellitus in patients undergoing THR and the associated risk of adverse operative outcomes. A meta-analysis and systematic review were conducted according to the guidelines of the meta-analysis of observational studies in epidemiology. Inclusion criteria were observational studies reporting the prevalence of diabetes in the study population, accompanied by reports of at least one of the following outcomes: venous thromboembolic events; acute coronary events; infections of the urinary tract, lower respiratory tract or surgical site; or requirement for revision arthroplasty. Altman and Bland’s methods were used to calculate differences in relative risks. The prevalence of diabetes mellitus was found to be 5.0% among patients undergoing THR, and was associated with an increased risk of established surgical site infection (odds ratio (OR) 2.04 (95% confidence interval (CI) 1.52 to 2.76)), urinary infection (OR 1.43 (95% CI 1.33 to 1.55)) and lower respiratory tract infections (OR 1.95 (95% CI 1.61 to 2.26)). Diabetes mellitus is a relatively common comorbidity encountered in THR. Diabetic patients have a higher rate of developing both surgical site and non-surgical site infections following THR.

Cite this article: Bone Joint J 2013;95-B:1474–9.

Down’s syndrome is associated with a number of musculoskeletal abnormalities, some of which predispose patients to early symptomatic arthritis of the hip. The purpose of the present study was to review the general and hip-specific factors potentially compromising total hip replacement (THR) in patients with Down’s syndrome, as well as to summarise both the surgical techniques that may anticipate the potential adverse impact of these factors and the clinical results reported to date. A search of the literature was performed, and the findings further informed by the authors’ clinical experience, as well as that of the hip replacement in Down Syndrome study group. The general factors identified include a high incidence of ligamentous laxity, as well as associated muscle hypotonia and gait abnormalities. Hip-specific factors include: a high incidence of hip dysplasia, as well as a number of other acetabular, femoral and combined femoroacetabular anatomical variations. Four studies encompassing 42 hips, which reported the clinical outcomes of THR in patients with Down’s syndrome, were identified. All patients were successfully treated with standard acetabular and femoral components. The use of supplementary acetabular screw fixation to enhance component stability was frequently reported. The use of constrained liners to treat intra-operative instability occurred in eight hips. Survival rates of between 81% and 100% at a mean follow-up of 105 months (6 to 292) are encouraging. Overall, while THR in patients with Down’s syndrome does present some unique challenges, the overall clinical results are good, providing these patients with reliable pain relief and good function.

Cite this article: Bone Joint J 2013;95-B, Supple A:41–5.

Patients with transfemoral amputation (TFA) often experience problems related to the use of socket-suspended prostheses. The clinical development of osseointegrated percutaneous prostheses for patients with a TFA started in 1990, based on the long-term successful results of osseointegrated dental implants.

Between1999 and 2007, 51 patients with 55 TFAs were consecutively enrolled in a prospective, single-centre non-randomised study and followed for two years. The indication for amputation was trauma in 33 patients (65%) and tumour in 12 (24%). A two-stage surgical procedure was used to introduce a percutaneous implant to which an external amputation prosthesis was attached. The assessment of outcome included the use of two self-report questionnaires, the Questionnaire for Persons with a Transfemoral Amputation (Q-TFA) and the Short-Form (SF)-36.

The cumulative survival at two years’ follow-up was 92%. The Q-TFA showed improved prosthetic use, mobility, global situation and fewer problems (all p < 0.001). The physical function SF-36 scores were also improved (p < 0.001). Superficial infection was the most frequent complication, occurring 41 times in 28 patients (rate of infection 54.9%). Most were treated effectively with oral antibiotics. The implant was removed in four patients because of loosening (three aseptic, one infection).

Osseointegrated percutaneous implants constitute a novel form of treatment for patients with TFA. The high cumulative survival rate at two years (92%) combined with enhanced prosthetic use and mobility, fewer problems and improved quality of life, supports the ‘revolutionary change’ that patients with TFA have reported following treatment with osseointegrated percutaneous prostheses.

Cite this article: Bone Joint J 2014;96-B:106–13.

Metal artefact reduction (MAR) MRI is now widely considered to be the standard for imaging metal-on-metal (MoM) hip implants. The Medicines and Healthcare Products Regulatory Agency (MHRA) has recommended cross-sectional imaging for all patients with symptomatic MoM bearings. This paper describes the natural history of MoM disease in a 28 mm MoM total hip replacement (THR) using MAR MRI. Inclusion criteria were patients with MoM THRs who had not been revised and had at least two serial MAR MRI scans. All examinations were reported by an experienced observer and classified as A (normal), B (infection) or C1–C3 (mild, moderate, severe MoM-related abnormalities). Between 2002 and 2011 a total of 239 MRIs were performed on 80 patients (two to four scans per THR); 63 initial MRIs (61%) were normal. On subsequent MRIs, six initially normal scans (9.5%) showed progression to a disease state; 15 (15%) of 103 THRs with sequential scans demonstrated worsening disease on subsequent imaging.

Most patients with a MoM THR who do not undergo early revision have normal MRI scans. Late progression (from normal to abnormal, or from mild to more severe MoM disease) is not common and takes place over several years.

Cite this article: Bone Joint J 2013;95-B:1035–9.

We report the survival, radiological and functional outcomes of a single surgeon series of his first 144 consecutive Birmingham hip resurfacing procedures (130 patients) at a minimum of ten years. There were ten revisions during this time. Although no patients were lost to follow-up some did not complete the scoring assessment or undergo radiological assessment at ten years.

The ten-year survival for male patients was 98.0% (95% confidence interval 95.2 to 100). The ten-year survival for the total cohort with aseptic revision as the endpoint was 95.5% (95% confidence interval 91.8 to 99.0) and including revisions for sepsis was 93.5% (95% confidence interval 89.2 to 97.6). The median modified Oxford hip score at ten years was 4.2% (interquartile range 0 to 19) and the median University of California, Los Angeles score was 7.0 (interquartile range 5.0 to 8.0).

This study confirms the midterm reports that metal-on-metal hip resurfacing using the Birmingham Hip provides a durable alternative to total hip replacement, particularly in younger male patients wishing to maintain a high level of function, with low risk of revision for at least ten years.

Intra-articular resection of bone with soft-tissue balancing and total knee replacement (TKR) has been described for the treatment of patients with severe osteoarthritis of the knee associated with an ipsilateral malunited femoral fracture. However, the extent to which deformity in the sagittal plane can be corrected has not been addressed. We treated 12 patients with severe arthritis of the knee and an extra-articular malunion of the femur by TKR with intra-articular resection of bone and soft-tissue balancing. The femora had a mean varus deformity of 16° (8° to 23°) in the coronal plane. There were seven recurvatum deformities with a mean angulation of 11° (6° to 15°) and five antecurvatum deformities with a mean angulation of 12° (6° to 15°).

The mean follow-up was 93 months (30 to 155). The median Knee Society knee and function scores improved from 18.7 (0 to 49) and 24.5 (10 to 50) points pre-operatively to 93 (83 to 100) and 90 (70 to 100) points at the time of the last follow-up, respectively. The mean mechanical axis of the knee improved from 22.6° of varus (15° to 27° pre-operatively to 1.5° of varus (3° of varus to 2° of valgus) at the last follow-up. The recurvatum deformities improved from a mean of 11° (6° to 15°) pre-operatively to 3° (0° to 6°) at the last follow-up. The antecurvatum deformities in the sagittal plane improved from a mean of 12° (6° to 16°) pre-operatively to 4.4° (0° to 8°) at the last follow-up.

Apart from varus deformities, TKR with intra-articular bone resection effectively corrected the extra-articular deformity of the femur in the presence of antecurvatum of up to 16° and recurvatum of up to 15°.

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.

We report the long-term clinical and radiological outcomes of the Aequalis total shoulder replacement with a cemented all-polyethylene flat-back keeled glenoid component implanted for primary osteoarthritis between 1991 and 2003 in nine European centres. A total of 226 shoulders in 210 patients were retrospectively reviewed at a mean of 122.7 months (61 to 219) or at revision. Clinical outcome was assessed using the Constant score, patient satisfaction score and range of movement. Kaplan-Meier survivorship analysis was performed with glenoid revision for loosening and radiological glenoid loosening (sd) as endpoints. The Constant score was found to improve from a mean of 26.8 (sd 10.3) pre-operatively to 57.6 (sd 20.0) post-operatively (p < 0.001). Active forward flexion improved from a mean of 85.3° (sd 27.4) pre-operatively to 125° (sd 37.3) postoperatively (p < 0.001). External rotation improved from a mean of 7° (sd 6.5) pre-operatively to 30.3° (sd 21.8°) post-operatively (p < 0.001). Survivorship with revision of the glenoid component as the endpoint was 99.1% at five years, 94.5% at ten years and 79.4% at 15 years. Survivorship with radiological loosening as the endpoint was 99.1% at five years, 80.3% at ten years and 33.6% at 15 years.

Younger patient age and the curettage technique for glenoid preparation correlated with loosening. The rate of glenoid revision and radiological loosening increased with duration of follow-up, but not until a follow-up of five years. Therefore, we recommend that future studies reporting radiological outcomes of new glenoid designs should report follow-up of at least five to ten years.

The August 2013 Foot & Ankle Roundup³⁶⁰ looks at: mobility, ankles and fractures; hindfoot nailing: not such a bad option after all?; little treatment benefit for blood injection in tendonitis; fixed bearing ankles successful in the short term; hindfoot motion following STAR ankle replacement; minimally invasive calcaneal fracture fixation?; pes planus in adolescents; and subluxing peroneals and groove deepening

We investigated the clinical outcome of internal fixation for pathological fracture of the femur after primary excision of a soft-tissue sarcoma that had been treated with adjuvant radiotherapy.

A review of our database identified 22 radiation-induced fractures of the femur in 22 patients (seven men, 15 women). We noted the mechanism of injury, fracture pattern and any complications after internal fixation, including nonunion, hardware failure, secondary fracture or deep infection.

The mean age of the patients at primary excision of the tumour was 58.3 years (39 to 86). The mean time from primary excision to fracture was 73.2 months (2 to 195). The mean follow-up after fracture fixation was 65.9 months (12 to 205). Complications occurred in 19 patients (86%). Nonunion developed in 18 patients (82%), of whom 11 had a radiological nonunion at 12 months, five a nonunion and hardware failure and two an infected nonunion. One patient developed a second radiation-associated fracture of the femur after internal fixation and union of the initial fracture. A total of 13 patients (59%) underwent 24 revision operations.

Internal fixation of a pathological fracture of the femur after radiotherapy for a soft-tissue sarcoma has an extremely high rate of complication and requires specialist attention.

Cite this article: Bone Joint J 2013;95-B:1144–8.

Impaction bone grafting for the reconstitution of bone stock in revision hip surgery has been used for nearly 30 years. Between 1995 and 2001 we used this technique in acetabular reconstruction, in combination with a cemented component, in 304 hips in 292 patients revised for aseptic loosening. The only additional supports used were stainless steel meshes placed against the medial wall or laterally around the acetabular rim to contain the graft. All Paprosky grades of defect were included. Clinical and radiographic outcomes were collected in surviving patients at a minimum of ten years after the index operation. Mean follow-up was 12.4 years (sd 1.5) (10.0 to 16.0). Kaplan–Meier survival with revision for aseptic loosening as the endpoint was 85.9% (95% CI 81.0 to 90.8) at 13.5 years. Clinical scores for pain relief remained satisfactory, and there was no difference in clinical scores between cups that appeared stable and those that appeared radiologically loose.

Cite this article: Bone Joint J 2014;96-B:188–94.

Lately, concerns have arisen following the use of large metal-on-metal bearings in hip replacements owing to reports of catastrophic soft-tissue reactions resulting in implant failure and associated complications. This review examines the literature and contemporary presentations on current clinical dilemmas in metal-on-metal hip replacement.