Aims

The aim of this study was to give estimates of the incidence of component incompatibility in hip and knee arthroplasty and to test the effect of an online, real-time compatibility check.

Whether patients with asymptomatic bacteriuria should be investigated and treated before elective hip and knee replacement is controversial, although it is a widespread practice. We conducted a prospective observational cohort study with urine analyses before surgery and three days post-operatively. Patients with symptomatic urinary infections or an indwelling catheter were excluded. Post-discharge surveillance included questionnaires to patients and general practitioners at three months. Among 510 patients (309 women and 201 men), with a median age of 69 years (16 to 97) undergoing lower limb joint replacements (290 hips and 220 knees), 182 (36%) had pre-operative asymptomatic bacteriuria, mostly due to Escherichia coli, and 181 (35%) had white cells in the urine. Most patients (95%) received a single intravenous peri-operative dose (1.5 g) of cefuroxime as prophylaxis. On the third post-operative day urinary analysis identified white cells in 99 samples (19%) and bacteriuria in 208 (41%). Pathogens in the cultures on the third post-operative day were different from those in the pre-operative samples in 260 patients (51%). Only 25 patients (5%) developed a symptomatic urinary infection during their stay or in a subsequent three-month follow-up period, and two thirds of organisms identified were unrelated to those found during the admission. All symptomatic infections were successfully treated with oral antibiotics with no perceived effect on the joint replacement.

We conclude that testing and treating asymptomatic urinary tract colonisation before joint replacement is unnecessary.

Cite this article: Bone Joint J 2014;96-B:390–4.

The aim of this study was to perform a cost–utility analysis of total hip (THR) and knee replacement (TKR). Arthritis is a disabling condition that leads to long-term deterioration in quality of life. Total joint replacement, despite being one of the greatest advances in medicine of the modern era, has recently come under scrutiny. The National Health Service (NHS) has competing demands, and resource allocation is challenging in times of economic restraint. Patients who underwent THR (n = 348) or TKR (n = 323) between January and July 2010 in one Scottish region were entered into a prospective arthroplasty database. A health–utility score was derived from the EuroQol (EQ-5D) score pre-operatively and at one year, and was combined with individual life expectancy to derive the quality-adjusted life years (QALYs) gained. Two-way analysis of variance was used to compare QALYs gained between procedures, while controlling for baseline differences. The number of QALYs gained was higher after THR than after TKR (6.5 vs 4.0 years, p < 0.001). The cost per QALY for THR was £1372 compared with £2101 for TKR. The predictors of an increase in QALYs gained were poorer health before surgery (p < 0.001) and younger age (p < 0.001). General health (EQ-5D VAS) showed greater improvement after THR than after TKR (p < 0.001). This study provides up-to-date cost-effectiveness data for total joint replacement. THR and TKR are extremely effective both clinically and in terms of cost effectiveness, with costs that compare favourably to those of other medical interventions.

Cite this article: Bone Joint J 2013;95-B:115–21.

We performed a meta-analysis of modern total joint replacement (TJR) to determine the post-operative mortality and the cause of death using different thromboprophylactic regimens as follows: 1) no routine chemothromboprophylaxis (NRC); 2) Potent anticoagulation (PA) (unfractionated or low-molecular-weight heparin, ximelagatran, fondaparinux or rivaroxaban); 3) Potent anticoagulation combined (PAC) with regional anaesthesia and/or pneumatic compression devices (PCDs); 4) Warfarin (W); 5) Warfarin combined (WAC) with regional anaesthesia and/or PCD; and 6) Multimodal (MM) prophylaxis, including regional anaesthesia, PCDs and aspirin in low-risk patients. Cause of death was classified as autopsy proven, clinically certain or unknown. Deaths were grouped into cardiopulmonary excluding pulmonary embolism (PE), PE, bleeding-related, gastrointestinal, central nervous system, and others (miscellaneous). Meta-analysis based on fixed effects or random effects models was used for pooling incidence data.

In all, 70 studies were included (99 441 patients; 373 deaths). The mortality was lowest in the MM (0.2%) and WC (0.2%) groups. The most frequent cause of death was cardiopulmonary (47.9%), followed by PE (25.4%) and bleeding (8.9%). The proportion of deaths due to PE was not significantly affected by the thromboprophylaxis regimen (PA, 35.5%; PAC, 28%; MM, 23.2%; and NRC, 16.3%). Fatal bleeding was higher in groups relying on the use of anticoagulation (W, 33.8%; PA, 9.4%; PAC, 10.8%) but the differences were not statistically significant.

Our study demonstrated that the routine use of PA does not reduce the overall mortality or the proportion of deaths due to PE.

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.