The June 2015 Foot & Ankle Roundup³⁶⁰ looks at: Syndesmosis and outcomes in ankle fracture; Ankle arthrodesis or arthroplasty: a complications-based analysis; Crosslinked polyethylene and ankle arthroplasty; Reducing screw removal in calcaneal osteotomies; Revisiting infection control policies; Chevron osteotomy: proximal or distal?; Ankle distraction for osteoarthritis

In England and Wales more than 175 000 hip and knee arthroplasties were performed in 2012. There continues to be a steady increase in the demand for joint arthroplasty because of population demographics and improving survivorship. Inevitably though the absolute number of periprosthetic infections will probably increase with severe consequences on healthcare provision. The Department of Health and the Health Protection Agency in United Kingdom established a Surgical Site Infection surveillance service (SSISS) in 1997 to undertake surveillance of surgical site infections. In 2004 mandatory reporting was introduced for one quarter of each year. There has been a wide variation in reporting rates with variable engagement with the process. The aim of this article is to improve surgeon awareness of the process and emphasise the importance of engaging with SSISS to improve the quality and type of data submitted. In Exeter we have been improving our practice by engaging with SSISS. Orthopaedic surgeons need to take ownership of the data that are submitted to ensure these are accurate and comprehensive.

Cite this article: Bone Joint J 2015;97-B:1170–4.

The number of arthroplasties being undertaken is expected to grow year on year, and periprosthetic joint infections will be an increasing socioeconomic burden. The challenge to prevent and eradicate these infections has resulted in the emergence of several new strategies, which are discussed in this review.

Cite this article: Bone Joint J 2015;97-B:1162–9.

Aims

Surgical site infection can be a devastating complication of hemiarthroplasty of the hip, when performed in elderly patients with a displaced fracture of the femoral neck. It results in a prolonged stay in hospital, a poor outcome and increased costs. Many studies have identified risk and prognostic factors for deep infection. However, most have combined the rates of infection following total hip arthroplasty and internal fixation as well as hemiarthroplasty, despite the fact that they are different entities. The aim of this study was to clarify the risk and prognostic factors causing deep infection after hemiarthroplasty alone.

Satisfactory primary wound healing following total joint replacement is essential. Wound healing problems can have devastating consequences for patients. Assessment of their healing capacity is useful in predicting complications. Local factors that influence wound healing include multiple previous incisions, extensive scarring, lymphoedema, and poor vascular perfusion. Systemic factors include diabetes mellitus, inflammatory arthropathy, renal or liver disease, immune compromise, corticosteroid therapy, smoking, and poor nutrition. Modifications in the surgical technique are necessary in selected cases to minimise potential wound complications. Prompt and systematic intervention is necessary to address any wound healing problems to reduce the risks of infection and other potential complications.

Cite this article: Bone Joint J 2013;95-B, Supple A:144–7.

Medium-term results of the Discovery elbow replacement are presented. We reviewed 51 consecutive primary Discovery total elbow replacements (TERs) implanted in 48 patients. The mean age of the patients was 69.2 years (49 to 92), there were 19 males and 32 females (37%:63%) The mean follow-up was 40.6 months (24 to 69). A total of six patients were lost to follow-up. Statistically significant improvements in range movement and Oxford Elbow Score were found (p < 0.001). Radiolucent lines were much more common in, and aseptic loosening was exclusive to, the humeral component. Kaplan–Meier survivorship at five years was 92.2% (95% CI 74.5% to 96.4%) for aseptic loosening. In four TERs, periprosthetic infection occurred resulting in failure. A statistically significant association between infection and increased BMI was found (p = 0.0268). Triceps failure was more frequent after the Mayo surgical approach and TER performed after previous trauma surgery. No failures of the implant were noted.

Our comparison shows that the Discovery has early clinical results that are similar to other semi-constrained TERs. We found continued radiological surveillance with particular focus on humeral lucency is warranted and has not previously been reported. Despite advances in the design of total elbow replacement prostheses, rates of complication remain high.

Cite this article: Bone Joint J 2014;96-B:1359–65

We report on 397 consecutive revision total hip replacements in 371 patients with a mean clinical and radiological follow-up of 12.9 years (10 to 17.7). The mean age at surgery was 69 years (37 to 93). A total of 28 patients (8%) underwent further revision, including 16 (4%) femoral components. In all 223 patients (56%, 233 hips) died without further revision and 20 patients (5%, 20 hips) were lost to follow-up. Of the remaining patients, 209 (221 hips) were available for clinical assessment and 194 (205 hips) for radiological review at mean follow-up of 12.9 years (10 to 17.7).

The mean Harris Hip Score improved from 58.7 (11 to 92) points to 80.7 (21 to 100) (p <  0.001) and the mean Merle d’Aubigné and Postel hip scores at final follow-up were 4.9 (2 to 6), 4.5 (2 to 6) and 4.3 (2 to 6), respectively for pain, mobility and function. Radiographs showed no lucencies around 186 (90.7%) femoral stems with stable bony ingrowth seen in 199 stems (97%). The survival of the S-ROM femoral stem at 15 years with revision for any reason as the endpoint was 90.5% (95% confidence interval (CI) 85.7 to 93.8) and with revision for aseptic loosening as the endpoint 99.3% (95% CI 97.2 to 99.8).

We have shown excellent long-term survivorship and good clinical outcome of a cementless hydroxyapatite proximally-coated modular femoral stem in revision hip surgery.

Cite this article: Bone Joint J 2014;96-B:730–6.

The October 2013 Knee Roundup³⁶⁰ looks at: Make it easy, release the MCL; Do patients remember clinical information in day surgery?; Osteoarthritis and arthroscopy?; How best to double your bundles; When to operate for infection; Cementless unicompartment knee replacement?; Tibial tubercle-trochlear groove confusion; Tarts, cherries and osteoarthritis

Prospective data on hip fracture from 3686 patients at a United Kingdom teaching hospital were analysed to investigate the risk factors, financial costs and outcomes associated with deep or superficial wound infections after hip fracture surgery.

In 1.2% (41) of patients a deep wound infection developed, and 1.1% (39) had a superficial wound infection. A total of 57 of 80 infections (71.3%) were due to Staphylococcus aureus and 39 (48.8%) were due to MRSA.

No statistically significant pre-operative risk factors were detected. Length of stay, cost of treatment and pre-discharge mortality all significantly increased with deep wound infection. The one-year mortality was 30%, and this increased to 50% in those who developed an infection (p < 0.001). A deep infection resulted in doubled operative costs, tripled investigation costs and quadrupled ward costs.

MRSA infection increased costs, length of stay, and pre-discharge mortality compared with non-MRSA infection.

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.

We report the clinical and radiological outcomes of a series of contemporary cementless ceramic-on-ceramic total hip replacements (THRs) at ten years in patients aged ≤ 55 years of age. Pre- and post-operative activity levels are described. A total of 120 consecutive ceramic cementless THRs were performed at a single centre in 110 patients from 1997 to 1999. The mean age of the patients at operation was 45 years (20 to 55). At ten years, four patients had died and six were lost to follow-up, comprising ten hips. The mean post-operative Harris hip score was 94.7 (55 to 100). Radiological analysis was undertaken in 90 available THRs of the surviving 106 hips at final review: all had evidence of stable bony ingrowth, with no cases of osteolysis. Wear was undetectable. There were four revisions. The survival for both components with revision for any cause as an endpoint was 96.5% (95% confidence interval 94.5 to 98.7). The mean modified University of California, Los Angeles activity level rose from a mean of 6.4 (4 to 10) pre-operatively to 9.0 (6 to 10) at the ten-year post-operative period.

Alumina ceramic-on-ceramic bearings in cementless primary THR in this series have resulted in good clinical and radiological outcomes with undetectable rates of wear and excellent function in the demanding younger patient group at ten years.

Cite this article: Bone Joint J 2013;95-B:1603–9.

The purpose of this article is to provide the reader with a seven-step checklist that could help in minimising the risk of PJI. The check list includes strategies that can be implemented pre-operatively such as medical optimisation, and reduction of the bioburden by effective skin preparation or actions taking during surgery such as administration of timely and appropriate antibiotics or blood conservation, and finally implementation of post-operative protocols such as efforts to minimise wound drainage and haematoma formation.

Cite this article: Bone Joint J 2016;98-B(1 Suppl A):18–22.

The debate whether to use cemented or uncemented components in primary total hip replacement (THR) has not yet been considered with reference to the cost implications to the National Health Service.

We obtained the number of cemented and uncemented components implanted in 2009 from the National Joint Registry for England and Wales. The cost of each component was established. The initial financial saving if all were cemented was then calculated. Subsequently the five-year rates of revision for each type of component were reviewed and the predicted number of revisions at five years for the actual components used was compared with the predicted number of revisions for a cemented THR. This was then multiplied by the mean cost of revision surgery to provide an indication of the savings over the first five years if all primary THRs were cemented.

The saving at primary THR was calculated to be £10 million with an additional saving during the first five years of between £5 million and £8.5 million. The use of cemented components in routine primary THR in the NHS as a whole can be justified on a financial level but we recognise individual patient factors must be considered when deciding which components to use.

We present our experience of the modified Dunn procedure in combination with a Ganz surgical dislocation of the hip to treat patients with severe slipped capital femoral epiphysis (SCFE). The aim was to prospectively investigate whether this technique is safe and reproducible. We assessed the degree of reduction, functional outcome, rate of complications, radiological changes and range of movement in the hip. There were 28 patients with a mean follow-up of 38.6 months (24 to 84). The lateral slip angle was corrected by a mean of 50.9° (95% confidence interval 44.3 to 57.5). The mean modified Harris hip score at the final follow-up was 89.1 (sd 9.0) and the mean Non-Arthritic Hip score was 91.3 (sd 9.0). Two patients had proven pre-existing avascular necrosis and two developed the condition post-operatively. There were no cases of nonunion, implant failure, infection, deep-vein thrombosis or heterotopic ossification. The range of movement at final follow-up was nearly normal. This study adds to the evidence that the technique of surgical dislocation and anatomical reduction is safe and reliable in patients with SCFE.

Cite this article: Bone Joint J 2013;95-B:424–9.

Patients with infected arthroplasties are normally treated with a two-stage exchange procedure using polymethylmethacrylate bone cement spacers impregnated with antibiotics. However, spacers may act as a foreign body to which micro-organisms may adhere and grow. In this study it was hypothesised that subclinical infection may be diagnosed with sonication of the surface biofilm of the spacer. The aims were to assess the presence of subclinical infection through sonication of the spacer at the time of a second-stage procedure, and to determine the relationship between subclinical infection and the clinical outcome. Of 55 patients studied, 11 (20%) were diagnosed with subclinical infection. At a mean follow-up of 12 months (interquartile range 6 to 18), clinical failure was found in 18 (32.7%) patients. Of the patients previously diagnosed with subclinical infection, 63% (7 of 11) had failed compared with 25% (11 of 44) of those without subclinical infection (odds ratio 5.25, 95% confidence interval 1.29 to 21.4, p = 0.021). Sonication of the biofilm of the surface of the spacer is useful in order to exclude subclinical infection and therefore contributes to improving the outcome after two-stage procedures.

We investigated the capacity of patient warming devices to disrupt the ultra-clean airflow system. We compared the effects of two patient warming technologies, forced-air and conductive fabric, on operating theatre ventilation during simulated hip replacement and lumbar spinal procedures using a mannequin as a patient. Infection data were reviewed to determine whether joint infection rates were associated with the type of patient warming device that was used.

Neutral-buoyancy detergent bubbles were released adjacent to the mannequin’s head and at floor level to assess the movement of non-sterile air into the clean airflow over the surgical site. During simulated hip replacement, bubble counts over the surgical site were greater for forced-air than for conductive fabric warming when the anaesthesia/surgery drape was laid down (p = 0.010) and at half-height (p < 0.001). For lumbar surgery, forced-air warming generated convection currents that mobilised floor air into the surgical site area. Conductive fabric warming had no such effect.

A significant increase in deep joint infection, as demonstrated by an elevated infection odds ratio (3.8, p = 0.024), was identified during a period when forced-air warming was used compared to a period when conductive fabric warming was used. Air-free warming is, therefore, recommended over forced-air warming for orthopaedic procedures.

Coloured bone cements have been introduced to make the removal of cement debris easier at the time of primary and revision joint replacement. We evaluated the physical, mechanical and pharmacological effects of adding methylene blue to bone cement with or without antibiotics (gentamicin, vancomycin or both). The addition of methylene blue to plain cement significantly decreased its mean setting time (570 seconds (sd 4) vs 775 seconds (sd 11), p = 0.01), mean compression strength (95.4 MPa (sd 3) vs 100.1 MPa (sd 6), p = 0.03), and mean bending strength (65.2 MPa (sd 5) vs 76.6 MPa (sd 4), p < 0.001) as well as its mean elastic modulus (2744 MPa (sd 97) vs 3281 MPa (sd 110), p < 0.001). The supplementation of the coloured cement with vancomycin and gentamicin decreased its mean bending resistance (55.7 MPa (sd 4) vs 65.2 MPa (sd 5), p < 0.001).The methylene blue significantly decreased the mean release of gentamicin alone (228.2 µg (sd 24) vs 385.5 µg (sd 26), p < 0.001) or in combination with vancomycin (498.5 µg (sd 70) vs 613 µg (sd 25), p = 0.018) from the bone cement. This study demonstrates several theoretical disadvantages of the antibiotic-loaded bone cement coloured with methylene blue.

Infection remains a significant and common complication after joint replacement and there is debate about which contributing factors are important. Few studies have investigated the effect of the operating time on infection.

We collected data prospectively from 5277 hip and knee replacements which included the type of procedure, the operating time, the use of drains, the operating theatre, surgeon, age and gender. In a subgroup of 3449 knee replacements further analysis was carried out using the tourniquet time in place of the operating time. These variables were assessed by the use of generalised linear modelling against superficial, deep or joint-space post-operative infection as defined by the Australian Surgical-Site Infection criteria.

The overall infection rate was 0.98%. In the replacement data set both male gender (z = 3.097, p = 0.00195) and prolonged operating time (z = 4.325, p < 0.001) were predictive of infection. In the knee subgroup male gender (z = 2.250, p = 0.02447), a longer tourniquet time (z = 2.867, p = 0.00414) and total knee replacement (versus unicompartmental knee replacement) (z = −2.052, p = 0.0420) were predictive of infection.

These findings support the view that a prolonged operating time and male gender are associated with an increased incidence of infection. Steps to minimise intra-operative delay should be instigated, and care should be exercised when introducing measures which prolong the duration of joint replacement.