Aims. The outcome of total knee arthroplasty (TKA) is not always satisfactory. The purpose of this study was to identify satisfaction and biomechanical features characterising the gait of patients who had undergone TKA with either an anatomical single radius design or a medial pivot design. We hypothesised that the latter would provide superior function. Patients and Methods. This is a study of a subset of patients recruited into a prospective randomised study of a single radius design versus a medial pivot design, with a minimum follow-up of one year. Outcome measurements included clinical scores (Knee Society Score (KSS) and Oxford Knee Score (OKS)) and gait analysis using an instrumented treadmill. Results. There was no statistically significant difference between the two groups for both the KSS and OKS. There was also no statistical significance in cadence, walking speed, stride length and stance time, peak stride, mid support and push-off forces. Conclusion. This study corroborates a previous study by the same authors that showed equally good results in clinical outcome and gait between the conventional single radius and medial pivot designs under stringent testing conditions. Cite this article: Bone Joint J 2018;(1 Supple A)100-B:76–82

Haematomas, drainage, and other non-infectious wound complications following total knee replacement (TKR) have been associated with long-term sequelae, in particular, deep infection. However, the impact of these wound complications on clinical outcome is unknown. This study compares results in 15 patients re-admitted for wound complications within 90 days of TKR to 30 matched patients who underwent uncomplicated total knee replacements. Patients with wound complications had a mean age of 66 years (49 to 83) and mean body mass index (BMI) of 37 (21 to 54), both similar to that of patients without complications (mean age 65 years and mean BMI 35). Those with complications had lower mean Knee Society function scores (46 (0 to 100 vs 66 (20 to 100), p = 0.047) and a higher incidence of mild or greater pain (73% vs 33%, p = 0.01) after two years compared with the non re-admitted group. Expectations in patients with wound complications following TKR should be tempered, even in those who do not develop an infection. Cite this article: Bone Joint J 2014;96-B:619–21

Aims

Tibial cones are often utilized in revision total knee arthroplasty (TKA) with metaphyseal defects. Because there are few studies evaluating mid-term outcomes with a sufficient cohort, the purpose of this study was to evaluate tibial cone survival and complications in revision TKAs with tibial cones at minimum follow-up of five years.

Aims. Surgical site infection (SSI) is a common complication of surgery with an incidence of about 1% in the United Kingdom. Sutures can lead to the development of a SSI, as micro-organisms can colonize the suture as it is implanted. Triclosan-coated sutures, being antimicrobical, were developed to reduce the rate of SSI. Our aim was to assess whether triclosan-coated sutures cause a reduction in SSIs following arthroplasty of the hip and knee. Patients and Methods. This two-arm, parallel, double-blinded study involved 2546 patients undergoing elective total hip (THA) and total knee arthroplasty (TKA) at three hospitals. A total of 1323 were quasi-randomized to a standard suture group, and 1223 being quasi-randomized to the triclosan-coated suture group. The primary endpoint was the rate of SSI at 30 days postoperatively. Results. The baseline characteristics of age, gender and comorbidities were well matched in the two groups. The rates of superficial SSI were 0.8% in the control group and 0.7% in the intervention group (p = 0.651), and when deep and superficial SSIs were combined the rates were 2.5% and 1.8 (p = 0.266). The length of stay in hospital and the rates of medical complications did not differ significantly between the groups (p = 1.000). Conclusion. This trial provided no evidence that the use of triclosan-coated sutures at THA and TKA leads to a reduction in the rate of SSI. Cite this article: Bone Joint J 2018;100-B:296–302

Aims

The primary aim was to assess the rate of postoperative COVID-19 following hip and knee arthroplasty performed in March 2020 in the UK. The secondary aims were to assess whether there were clinical factors associated with COVID-19 status, the mortality rate of patients with COVID-19, and the rate of potential COVID-19 in patients not presenting to healthcare services.

Mobile-bearing (MB) total knee replacement (TKR) was introduced to reduce the risk of aseptic loosening and wear of polyethylene inserts. However, no consistent clinical advantages of mobile- over fixed-bearing (FB) TKR have been found. In this study we evaluated whether mobile bearings have an advantage over fixed bearings with regard to revision rates and clinical outcome scores. Furthermore, we determined which modifying variables affected the outcome. A systematic search of the literature was conducted to collect clinical trials comparing MB and FB in primary TKR. The primary outcomes were revision rates for any reason, aseptic loosening and wear. Secondary outcomes included range of movement, Knee Society score (KSS), Oxford knee score (OKS), Short-Form 12 (SF-12) score and radiological parameters. Meta-regression techniques were used to explore factors modifying the observed effect. . Our search yielded 1827 publications, of which 41 studies met our inclusion criteria, comprising over 6000 TKRs. Meta-analyses showed no clinically relevant differences in terms of revision rates, clinical outcome scores or patient-reported outcome measures between MB and FB TKRs. It appears that theoretical assumptions of superiority of MB over FB TKR are not borne out in clinical practice. Cite this article: Bone Joint J 2013;95-B:1209–16

The Oxford hip and knee scores (OHS and OKS) are validated patient-reported outcome measures used in patients undergoing total hip replacement (THR), hip resurfacing (HR), total knee replacement (TKR) and unicompartmental knee replacement (UKR). We analysed the absolute OHS and OKS and change in scores following THR, HR, TKR, and UKR performed at one specialist centre. All patients undergoing and completing at least one Oxford score were eligible for inclusion in the study which included 27 950 OHS and 19 750 OKS in 13 682 patients. Data were analysed using non-linear quantile regression. The median absolute Oxford scores for THR, HR, TKR and UKR were pre-operative 68.8% (15.0/48), 58.3% (20.0/48), 66.7% (16.0/48), 60.4% (19.0/48) respectively: and post-operative asymptote was 14.6% (41.0/48), 5.8% (45.2/48), 31.2% (33.0/48), 29.2% (34.0/48). The median asymptotic change from the pre-operative score for THR, HR, TKR and UKR were 47.9% (23.0/48), 47.9% (23.0/48), 33.3% (16.0/48) and 32.4% (15.5/48), respectively. The median time at which no further appreciable change in score was achieved post-operatively was 0.7 years for THR, 1.1 years for HR, 0.9 years for TKR and 1.1 years for UKR. The curves produced from this analysis could be used to educate patients, and to audit the performance of a surgeon and an institution. The time to achieve a stable improvement in outcome varied between different types of joint replacement, which may have implications for the timing of post-operative review. Cite this article: Bone Joint J 2014; 96-B:928–35

Aims

Single-stage revision total knee arthroplasty (rTKA) is gaining popularity in treating chronic periprosthetic joint infections (PJIs). We have introduced this approach to our clinical practice and sought to evaluate rates of reinfection and re-revision, along with predictors of failure of both single- and two-stage rTKA for chronic PJI.

Symptomatic and asymptomatic deep-vein thrombosis (DVT) is a common complication of knee replacement, with an incidence of up to 85% in the absence of prophylaxis. National guidelines for thromboprophylaxis in knee replacement are derived from total knee replacement (TKR) data. No guidelines exist specific to unicompartmental knee replacement (UKR). We investigated whether the type of knee arthroplasty (TKR or UKR) was related to the incidence of DVT and discuss the applicability of existing national guidelines for prophylaxis following UKR. . Data were collected prospectively on 3449 knee replacements, including procedure type, tourniquet time, surgeon, patient age, use of drains and gender. These variables were related to the incidence of symptomatic DVT. The overall DVT rate was 1.6%. The only variable that had an association with DVT was operation type, with TKR having a higher incidence than UKR (2.2% versus 0.3%, p < 0.001). These data show that the incidence of DVT after UKR is both clinically and statistically significantly lower than that after TKR. . TKR and UKR patients have different risk profiles for symptomatic DVT. The risk-benefit ratio for TKR that has been used to produce national guidelines may not be applicable to UKR. Further research is required to establish the most appropriate form of prophylaxis for UKR

Aims

A typical pattern of blood loss associated with total hip arthroplasty (THA) is 200 ml intraoperatively and 1.3 l in the first 48 postoperative hours. Tranexamic acid (TXA) is most commonly given as a single preoperative dose only and is often withheld from patients with a history of thromboembolic disease as they are perceived to be “high-risk” with respect to postoperative venous thromboembolism (VTE). The TRanexamic ACid for 24 hours trial (TRAC-24) aimed to identify if an additional 24-hour postoperative TXA regime could further reduce blood loss beyond a once-only dose at the time of surgery, without excluding these high-risk patients.

Peri-prosthetic patellar fracture following resurfacing as part of total knee replacement (TKR) is an infrequent yet challenging complication. This case-control study was performed to identify clinical, radiological and surgical factors that increase the risk of developing a spontaneous patellar fracture after TKR. Patellar fractures were identified in 74 patients (88 knees) from a series of 7866 consecutive TKRs conducted between 1998 and 2009. After excluding those with a previous history of extensor mechanism realignment or a clear traumatic event, a metal-backed patella, any uncemented component or subsequent infection, the remaining 64 fractures were compared with a matched group of TKRs with an excellent outcome defined by the Knee Society score. The mean age of patients with a fracture was 70 years (51 to 81) at the time of TKR. Patellar fractures were detected at a mean of 13.4 months (2 to 84) after surgery. The incidence of patellar fracture was found to be strongly associated with the number of previous knee operations, greater pre-operative mechanical malalignment, smaller post-operative patellar tendon length, thinner post-resection patellar thickness, and a lower post-operative Insall-Salvati ratio. An understanding of the risk factors associated with spontaneous patellar fracture following TKR provides a valuable insight into prevention of this challenging complication

Bariatric surgery has been advocated as a means of reducing body mass index (BMI) and the risks associated with total knee arthroplasty (TKA). However, this has not been proved clinically. In order to determine the impact of bariatric surgery on the outcome of TKA, we identified a cohort of 91 TKAs that were performed in patients who had undergone bariatric surgery (bariatric cohort). These were matched with two separate cohorts of patients who had not undergone bariatric surgery. One was matched 1:1 with those with a higher pre-bariatric BMI (high BMI group), and the other was matched 1:2 based on those with a lower pre-TKA BMI (low BMI group). In the bariatric group, the mean BMI before bariatric surgery was 51.1 kg/m. 2 . (37 to 72), which improved to 37.3 kg/m. 2. (24 to 59) at the time of TKA. Patients in the bariatric group had a higher risk of, and worse survival free of, re-operation (hazard ratio (HR) 2.6; 95% confidence interval (CI) 1.2 to 6.2; p = 0.02) compared with the high BMI group. Furthermore, the bariatric group had a higher risk of, and worse survival free of re-operation (HR 2.4; 95% CI 1.2 to 3.3; p = 0.2) and revision (HR 2.2; 95% CI 1.1 to 6.5; p = 0.04) compared with the low BMI group. . While bariatric surgery reduced the BMI in our patients, more analysis is needed before recommending bariatric surgery before TKA in obese patients. Cite this article: Bone Joint J 2015;97-B:1501–5

The aim of our study was to describe the characteristics, treatment, and outcomes of patients with periprosthetic joint infection (PJI) and normal inflammatory markers after total knee arthroplasty (TKA) and total hip arthroplasty (THA). . In total 538 TKAs and 414 THAs underwent surgical treatment for PJI and met the inclusion criteria. Pre-operative erythrocyte sedimentation rate (ESR) and C-reactive protein level (CRP) were reviewed to identify the seronegative cohort. An age- and gender-matched cohort was identified from the remaining patients for comparison. Overall, 4% of confirmed infections were seronegative (21 TKA and 17 THA). Of those who underwent pre-operative aspiration, cultures were positive in 76% of TKAs (n = 13) and 64% of THAs (n = 7). Cell count and differential were suggestive of infection in 85% of TKA (n = 11) and all THA aspirates (n = 5). The most common organism was coagulase-negative Staphylococcus. Seronegative infections were associated with a lower aspirate cell count and a lower incidence of Staphylococcus aureus infection. Two-stage revision was performed in 35 cases (95%). At a mean of five years (14 to 162 months) following revision, re-operation for infection occurred in two TKAs, and one THA. From our study we estimate around 4% of patients with PJI may present with normal ESR and CRP. When performed, pre-operative aspirate is useful in delivering a definitive diagnosis. When treated, similar outcomes can be obtained compared with patients with positive serology. Cite this article: Bone Joint J 2015;97-B:939–44