Introduction. First generation cephalosporins remain the gold standard perioperative antibiotic for total hip and knee arthroplasty (THA, TKA). However, some patients have documented or self-reported allergies to antibiotics, most commonly penicillin, that result in changes to perioperative antibiotic coverage. Furthermore, patients testing positive for methicillin resistant staphylococcus aureus (MRSA) represent another group where an alternative to cefazolin, typically vancomycin, is often chosen for perioperative prophylaxis. The aims of this study were to 1) characterize the antibiotic choices for perioperative prophylaxis at the time of primary TKA and THA, 2) assess the efficacy of a preoperative antibiotic allergy testing program, and 3) determine rates of periprosthetic joint infection (PJI) based on perioperative antibiotic regimen. Methods. We evaluated all patients undergoing primary TKA or THA at a single academic institution from January 2004-May 2017, yielding a cohort of 29,695 patients. A series of institutional databases were combined to determine which patients underwent antibiotic allergy testing prior to surgery, outcomes from the allergy consultation, perioperative antibiotic management strategy, and survivorship free of infection until final follow-up. Results. Antibiotic allergy testing was performed in 3,411 patients (11.5%) on the basis of a patient provided history of possible penicillin or cephalosporin allergy. Among those tested, 3,310 patients (97.0%) were cleared by the allergist to use cephalosporins in the perioperative period and 2,883 patients (87.1%) eventually received cefazolin. For the entire cohort, 28,174 patients (94.9%) received an operative antibiotic regimen including cefazolin and 1,521 patients (5.1%) received non-cefazolin antibiotics, most commonly vancomycin or clindamycin. Survivorship free of PJI was significantly higher among patients receiving cefazolin compared to non-cefazolin antibiotics with the most rapid divergence occurring within 2 months of surgery (p<0.001) (Figure 1). Survivorship free of PJI in the cefazolin compared to the non-cefazolin groups was 99.40% vs 99.34% at 1 month, 99.11% vs 98.55% at 2 months, 98.83% vs 98.22% at 1 year, and 98.15% vs 96.96% at 10 years (Table 1). Notably, the increased PJI rate observed in the non-cefazolin group was not attributable to high preoperative MRSA prevalence as 0 of the 38 PJIs grew MRSA on culture. The number needed to treat with cefazolin to prevent 1 PJI was 164 patients at 1-year and 84 patients at 10-years. Therefore, potentially 6,098 PJIs could be prevented by 1-year and 11,905 by 10-years in a cohort of 1,000,000 primary TKA and THA patients. Conclusions. This study demonstrates a significantly higher rate of PJI when non-cefazolin antibiotics are used for prophylaxis during primary TKA and THA, which is likely attributable to the superior spectrum of coverage for common PJI organisms compared to vancomycin or clindamycin. This is supported by the increased rate of non-MRSA PJI observed in the non-cefazolin cohort. Furthermore, cefazolin has been shown to act synergistically with vancomycin against MRSA. This work highlights the positive impact of a formal preoperative antibiotic allergy testing program to increase cefazolin usage. Also, surgeons may consider using cefazolin as a dual agent in the case of known MRSA colonization, whenever possible for PJI prophylaxis during TKA and THA. For any figures or tables, please contact authors directly

Antibiotic prophylaxis for joint replacement surgery is widely recommended and has been shown to reduce infection rates. Cephalosporins have commonly been used but are associated with development of Clostridium difficile associated diarrhoea (CDAD). The purpose of this study was to assess whether a change of protocol aimed at reducing CDAD, including a change of antibiotic prophylaxis would reduce rates of CDAD and other postoperative complications. We studied all 7989 patients in our trust that underwent hip or knee replacement from May 2002 to March 2009. These patients fell into two cohorts, firstly those who were prescribed cefuroxime as prophylaxis and secondly those prescribed gentamicin which was introduced following national concern regarding CDAD. Following the change of prophylaxis from cefuroxime 750mg three doses to gentamicin 4.5 mg/kg single dose the rate of CDAD reduced significantly (0.17% to 0%, p<0.03), however the rate of acute renal failure (0.29% to 0.6%, p=0.04) and pneumonia (0.71% to 1.38%, p<0.01) increased significantly. The rate of urinary tract infection (1.44% to 1.20%, p >0.05) and the overall return to theatre rate (1.86% to 2.30%, p=0.21) were not significantly changed. The spectrum of bacteria grown from infected joint replacements in the two cohorts was also analysed. The rate of deep MRSA infection was significantly less in the group given gentamicin. The frequency of other bacteria was also different between the cohorts, but not significantly so. We conclude that changing protocol including antibiotic prophylaxis in joint replacement patients can have the desired effect on a particular outcome namely CDAD but can also result in increased rates of other postoperative complications. It is also likely to result in a change in the bacterial spectrum of infected joint replacements

The optimal characteristics of pneumatic compression for mechanical prophylaxis of thromboembolism after total knee arthroplasty (TKA) are not known. Our study compared two methods of calf compression, with the hypothesis that the device which provided a larger increase in peak venous velocity would produce a lower rate of thromboembolism. We performed a prospective, randomised study on 423 patients (472 knees). Duplex ultrasonography was carried out by experienced technicians who were blinded to the device used. Overall, 206 patients (232 knees) used a rapid inflation, asymmetrical compression (RIAC) device and 217 (240 knees) a sequential circumferential compression device (SCD). The rate of venous thromboembolism was 6.9% with the RIAC device compared with 15% for the SCD device (p = 0.007). The incidence of thrombi with unilateral primary TKA was 8.4% for the RIAC compared with 16.8% for the SCD device (p = 0.03). In 47 patients with a bilateral TKA, the incidence of thrombi was 4% for the RIAC compared with 22.7% for the SCD device (p = 0.05 per knee). There was a low rate of mortality and pulmonary embolism when using mechanical prophylaxis for thromboembolism after TKA. Our findings show that the use of rapid inflation, asymmetrical calf compression gave a significantly lower rate of thromboembolism

We compared thromboembolic events, major haemorrhage and death after knee replacement in patients receiving either aspirin or low-molecular-weight heparin (LMWH). Data from the National Joint Registry for England and Wales were linked to an administrative database of hospital admissions in the English National Health Service. A total of 156 798 patients between April 2003 and September 2008 were included and followed for 90 days. Multivariable risk modelling was used to estimate odds ratios adjusted for baseline risk factors (AOR). An AOR < 1 indicates that risk rates are lower with LMWH than with aspirin. In all, 36 159 patients (23.1%) were prescribed aspirin and 120 639 patients (76.9%) were prescribed LMWH. We found no statistically significant differences between the aspirin and LMWH groups in the rate of pulmonary embolism (0.49% vs 0.45%, AOR 0.88 (95% confidence interval (CI) 0.74 to 1.05); p = 0.16), 90-day mortality (0.39% vs 0.45%, AOR 1.13 (95% CI 0.94 to 1.37); p = 0.19) or major haemorrhage (0.37% vs 0.39%, AOR 1.01 (95% CI 0.83 to 1.22); p = 0.94). There was a significantly greater likelihood of needing to return to theatre in the aspirin group (0.26% vs 0.19%, AOR 0.73 (95% CI 0.58 to 0.94); p = 0.01). Between patients receiving LMWH or aspirin there was only a small difference in the risk of pulmonary embolism, 90-day mortality and major haemorrhage.

These results should be considered when the existing guidelines for thromboprophylaxis after knee replacement are reviewed.

Aims. Despite recent literature questioning their use, vancomycin and clindamycin often substitute cefazolin as the preoperative antibiotic prophylaxis in primary total knee arthroplasty (TKA), especially in the setting of documented allergy to penicillin. Topical povidone-iodine lavage and vancomycin powder (VIP) are adjuncts that may further broaden antimicrobial coverage, and have shown some promise in recent investigations. The purpose of this study, therefore, is to compare the risk of acute periprosthetic joint infection (PJI) in primary TKA patients who received cefazolin and VIP to those who received a non-cephalosporin alternative and VIP. Methods. This was a retrospective cohort study of 11,550 primary TKAs performed at an orthopaedic hospital between 2013 and 2019. The primary outcome was PJI occurring within 90 days of surgery. Patients were stratified into two groups (cefazolin vs non-cephalosporin) based on their preoperative antibiotic. All patients also received the VIP protocol at wound closure. Bivariate and multiple logistic regression analyses were performed to control for potential confounders and identify the odds ratio of PJI. Results. In all, 10,484 knees (90.8%) received cefazolin, while 1,066 knees (9.2%) received a non-cephalosporin agent (either vancomycin or clindamycin) as preoperative prophylaxis. The rate of PJI in the cefazolin group (0.5%; 48/10,484) was significantly lower than the rate of PJI in the non-cephalosporin group (1.0%; 11/1,066) (p = 0.012). After controlling for confounding variables, the odds ratio (OR) of developing a PJI was increased in the non-cephalosporin cohort compared to the cefazolin cohort (OR 2.389; 1.2 to 4.6); p = 0.01). Conclusion. Despite the use of topical irrigant solutions and addition of local antimicrobial agents, the use of a non-cephalosporin perioperative antibiotic continues to be associated with a greater risk of TKA PJI compared to cefazolin. Strategies that increase the proportion of patients receiving cefazolin rather than non-cephalosporin alternatives must be emphasized. Cite this article: Bone Jt Open 2022;3(1):35–41

Aims. The aims of this study were to compare the efficacy of two agents, aspirin and warfarin, for the prevention of venous thromboembolism (VTE) after simultaneous bilateral total knee arthroplasty (SBTKA), and to elucidate the risk of VTE conferred by this procedure compared with unilateral TKA (UTKA). Patients and Methods. A retrospective, multi-institutional study was conducted on 18 951 patients, 3685 who underwent SBTKA and 15 266 who underwent UTKA, using aspirin or warfarin as VTE prophylaxis. Each patient was assigned an individualised baseline VTE risk score based on a system using the Nationwide Inpatient Sample. Symptomatic VTE, including pulmonary embolism (PE) and deep vein thrombosis (DVT), were identified in the first 90 days post-operatively. Statistical analyses were performed with logistic regression accounting for baseline VTE risk. Results. The adjusted incidence of PE following SBTKA was 1.0% (95% confidence interval (CI) 0.86 to 1.2) with aspirin and 2.2% (95% CI 2.0 to 2.4) with warfarin. Similarly, the adjusted incidence of VTE following SBTKA was 1.6% (95% CI 1.1 to 2.3) with aspirin and 2.5% (95% CI 1.9 to 3.3) with warfarin. The risk of PE and VTE were reduced by 66% (odds ratio (OR) 0.44, 95% CI 0.25 to 0.78) and 38% (OR 0.62, 95% CI 0.38 to 1.0), respectively, using aspirin. In addition, the risk of PE was 204% higher for patients undergoing SBTKA relative to those undergoing UTKA. For each ten-point increase in baseline VTE risk, the risk of PE increased by 25.5% for patients undergoing SBTKA compared with 10.5% for those undergoing UTKA. Patients with a history of myocardial infarction or peripheral vascular disease had the greatest increase in risk from undergoing SBTKA instead of UTKA. Conclusion. Aspirin is more effective than warfarin for the prevention of VTE following SBTKA, and serves as the more appropriate agent for VTE prophylaxis for patients in all risk categories. Furthermore, patients undergoing SBTKA are at a substantially increased risk of VTE, even more so for those with significant underlying risk factors. Patients should be informed about the risks associated with undergoing SBTKA. Cite this article: Bone Joint J 2018;100-B(1 Supple A):68–75

Introduction. Vancomycin is a commonly used antibiotic for prophylaxis in total joint replacement surgery. Several studies have reported superior local tissue concentration of vancomycin using intraosseous (IO) infusion compared with standard intravenous (IV) administration in total knee arthroplasty (TKA). We reviewed patients undergoing primary TKA who received IO vancomycin to a group receiving IV vancomycin. Methods. A retrospective review of 1038 patient who underwent primary TKA at our institution was performed from May 1, 2016 to May 1, 2019. This was a consecutive series of patients before and after we adopted this technique. IO vancomycin administration technique has been previously reported from our institution (500mg vancomycin in 200mL solution). Comparisons included preoperative and postoperative creatinine values, adverse reaction to vancomycin, tourniquet time, re-operation rates, periprosthetic joint infection rate at 1 year. Results. There were 482 patients in IO vancomycin group and 572 patients in IV vancomycin group. No differences between groups were present for patient age, sex, or BMI. No differences in creatinine values or tourniquet time were present and there were no adverse reactions to vancomycin in either group. Eight periprosthetic joint infections (1.4%) were reported in the IV group, and 1 (0.2%) periprosthetic joint infection was reported in the IO group at 1 year follow up, and this was statistically significant (p = 0.04, Fishers exact test). The overall reoperation rate was 1.7% (10 patients) in the IV group and 1.1% (5 patients), however, this was not statistically significant (p = 0.4371). The additional reoperations were for retained suture or small areas of poor superficial wound healing and were considered minor. Conclusion. Our study demonstrated that IO vancomycin in primary TKA reduced periprosthetic joint infection and is a safe and effective alternative to IV administration. Furthermore, IO infusion also eliminates the logistical challenges of timely prophylactic antibiotic administration before TKA

Purpose of the study. To determine the effectiveness, complications and side effects of Rivaroxaban when used for extended thromboprophylaxis in patients undergoing primary and revision knee arthroplasty. Methods. Venous Thromboembolism (VTE) prophylaxis following knee arthroplasty remains controversial. As an Orthopaedic Unit, in July 2009 we developed guidelines to help ensure that our patient management was fully compliant with National Institute for Health and Clinical Excellence (NICE) guidelines regarding risk assessment and extended oral prophylaxis following primary and revision knee arthroplasty. We opted to trial the oral anticoagulant drug Rivaroxaban for an initial period of 12 months. All patients undergoing primary or revision knee arthroplasty between 1. st. July 2009 and 30. th. June 2010 and who had no contraindications to the prescription of Rivaroxaban were included in a prospective audit aimed at determining compliance with the newly developed unit guidelines as well as the effectiveness and possible side effects/complications associated with the drug therapy. All patients were monitored for a period of 90 days post operatively. Results. A total of 415 patients were included in the audit (336 primary knee arthroplasty, 27 revision knee arthroplasty, 6 patello-femoral resurfacing, 46 medial unicompartmental knee arthroplasty). Of this group eight had a confirmed VTE (six deep vein thrombosis, two pulmonary embolism). A further 29 patients had post-operative complications which may be attributed in part to the action of Rivaroxaban. The drug was discontinued prematurely for 22 patients. Conclusions. Our results indicate that Rivaroxaban is effective in providing extended VTE prophylaxis to patients undergoing knee arthroplasty surgery. However, as anticipated, anticoagulation therapy does cause associated wound problems

Aims

This study compared patient-reported outcomes of three total knee arthroplasty (TKA) designs from one manufacturer: one cruciate-retaining (CR) design, and two cruciate-sacrificing designs, anterior-stabilized (AS) and posterior-stabilized (PS).

Introduction. There is insufficient data on the trends of anticoagulation after total knee arthroplasty (TKA) in the USA, and the efficacy and safety of rivaroxaban, beyond randomized clinical trials and small cohort studies. Patients and Methods. Using the Truven Health MarketScan database, we retrospectively evaluated new anticoagulation prescriptions after elective TKA from 2010 to 2015. The frequency of deep vein thrombosis (DVT), pulmonary embolism (PE), and adverse events, within 90 days, were then evaluated in 24,856 new users of warfarin and 21,398 new users of rivaroxaban in commercially insured patients (COM), and 15,483 new users of warfarin and 8,997 new users of rivaroxaban in Medicare supplement patients (MED). Data was analyzed by odds ratios using logistic regression models with stabilized inverse probability treatment weighting. Results. Warfarin use decreased from approximately 50% to 17% in COM patients and 60% to 25% in MED patients. Rivaroxaban use increased from 0 to 35% in COM patients and from 0 to 39% in MED patients. Older patients, females, a history of DVT, renal impairment, use of antiplatelet agents or surgery performed as an outpatient had lower odds of getting rivaroxaban. Patients in Western region and having surgery in 2015 had higher odds of getting rivaroxaban. COM patients with capitated insurance plans and a history of PE had lower odds of rivaroxaban initiation. MED patients with atrial fibrillation, cardiovascular disease or hyperlipidemia had lower odds of rivaroxaban initiation. Warfarin users had significantly higher odds ratio of DVT (OR 2.06 in COM patients and OR 2.21 in MED patients) and PE (OR 2.03 in COM patients and OR 2.16 in MED patients) than rivaroxaban users. There were no statistically significant differences in the bleeding risk between the two agents, but warfarin users had a significantly higher odds ratio of periprosthetic infection in both COM (1.57) and MED (1.79) patients. Conclusions. There has been an increase in prophylaxis with rivaroxaban, and a decrease in both warfarin and LMWH use after elective TKA over four years. Rivaroxaban had lower odds ratio of both DVT and PE than warfarin, and bleeding risks were similar. For figures, tables, or references, please contact authors directly

Aims

As has been shown in larger animal models, knee immobilization can lead to arthrofibrotic phenotypes. Our study included 168 C57BL/6J female mice, with 24 serving as controls, and 144 undergoing a knee procedure to induce a contracture without osteoarthritis (OA).

The optimal regime of antithrombotic prophylaxis for patients undergoing total knee arthroplasty (TKA) has not been established. Many surgeons employ intermittent pneumatic compression while others use low-molecular-weight heparins (LMWH) which were primarily developed for total hip arthroplasty. We compared the efficacy and safety of these two techniques in a randomised study with blinded assessment of the endpoint by phlebography. We randomised 130 patients, scheduled for elective TKA, to receive one daily subcutaneous injection of nadroparin calcium (dosage adapted to body-weight) or continuous intermittent pneumatic compression of the foot by means of the arteriovenous impulse system. A total of 108 patients (60 in the LMWH group and 48 in the mechanical prophylaxis group) had phlebography eight to 12 days after surgery. Of the 47 with deep-vein thrombosis, 16 had received LMWH (26.7%, 95% CI 16.1 to 39.7) and 31, mechanical prophylaxis (64.6%, 95% CI 49.5 to 77.8). The difference between the two groups was highly significant (p < 0.001). Only one patient in the LMWH group had severe bleeding. We conclude that one daily subcutaneous injection of calcium nadroparin in a fixed, weight-adjusted dosage scheme is superior to intermittent pneumatic compression of the foot for thromboprophylaxis after TKA. The LMWH scheme was also safe

NICE guidelines state patients undergoing elective TKR receive post-operative chemical prophylaxis unless contraindicated, following guideline implementation our aim was to determine VTE incidence and wound complication outcomes related to administration of Rivaroxaban or Enoxaparin. From April to October 2010 we prospectively studied 294 patients having primary or revision TKR. Each received either Rivaroxoban (n=219), Enoxaparin (n=68), UHF 5000 units (n=4) or no thromboprohylaxis (n=3) post-operatively. Primary outcome was identification of symptomatic post-operative VTE incidence and compared incidence over the same period in 2009 when aspirin was the standard chemical prophylaxis for VTE. Secondary outcomes were prolonged wound oozing rates and wound washout. VTE occurred in 3 of 219 patients (2 PE, 1 DVT) receiving Rivaroxaban, and 1 PE in a patient who did not receive any thromboprophylaxis. No patients prescribed Enoxaparin developed VTE. In the same period 2009 there were 21 confirmed PEs in 512 patients undergoing TKR. This was statistically significant (Chi squared test p=0.02). Prolonged oozing was noted in 3 patients receiving Enoxaparin, and 17 patients receiving Rivaroxaban. 6 patients treated with Rivaroxaban returned to theatre, 3 for continuous ooze, 2 for wound dehiscence and 1 for infection. During the same period in 2009, there was only 1 return to theatre for haematoma washout. (Chi squared test; p=0.02). Following the NICE guidelines, there is a reduction in the PE rate following TKR but there is an increase in the overall return to theatre rate

Aims

Access to total knee arthroplasty (TKA) is sometimes restricted for patients with severe obesity (BMI ≥ 40 kg/m²). This study compares the cost per quality-adjusted life year (QALY) associated with TKA in patients with a BMI above and below 40 kg/m² to examine whether this is supported.

Aims

Intra-articular administration of antibiotics during primary total knee arthroplasty (TKA) may represent a safe, cost-effective strategy to reduce the risk of acute periprosthetic joint infection (PJI). Vancomycin with an aminoglycoside provides antimicrobial cover for most organisms isolated from acute PJI after TKA. However, the intra-articular doses required to achieve sustained therapeutic intra-articular levels while remaining below toxic serum levels is unknown. The purpose of this study is to determine the intra-articular and serum levels of vancomycin and tobramycin over the first 24 hours postoperatively after intra-articular administration in primary cementless TKA.

Aims

The optimal management of an infrapopliteal deep venous thrombosis (IDVT) following total knee arthroplasty (TKA) remains unknown. The risk of DVT propagation and symptom progression must be balanced against potential haemorrhagic complications associated with administration of anticoagulation therapy. The current study reports on a cohort of patients diagnosed with IDVT following TKA who were treated with aspirin, followed closely for development of symptoms, and scanned with ultrasound to determine resolution of IDVT.

Aims

The management of periprosthetic joint infection (PJI) after total knee arthroplasty (TKA) is challenging. The correct antibiotic management remains elusive due to differences in epidemiology and resistance between countries, and reports in the literature. Before the efficacy of surgical treatment is investigated, it is crucial to analyze the bacterial strains causing PJI, especially for patients in whom no organisms are grown.

Aims

To describe the risk of periprosthetic joint infection (PJI) and reoperation in patients who have an acute, traumatic wound dehiscence following total knee arthroplasty (TKA).

Aims

Infection complicating primary total knee arthroplasty (TKA) is a common reason for revision surgery, hospital readmission, patient morbidity, and mortality. Increasing incidence of methicillin-resistant Staphylococcus aureus (MRSA) is a particular concern. The use of vancomycin as prophylactic agent alone or in combination with cephalosporin has not demonstrated lower periprosthetic joint infection (PJI) rates, partly due to timing and dosing of intravenous (IV) vancomycin administration, which have proven important factors in effectiveness. This is a retrospective review of a consecutive series of primary TKAs examining incidence of PJI, adverse reactions, and complications using IV versus intraosseous (IO) vancomycin at 30-day, 90-day, and one-year follow-up.

Aims

In total knee arthroplasty (TKA), blood loss continues internally after surgery is complete. Typically, the total loss over 48 postoperative hours can be around 1,300 ml, with most occurring within the first 24 hours. We hypothesize that the full potential of tranexamic acid (TXA) to decrease TKA blood loss has not yet been harnessed because it is rarely used beyond the intraoperative period, and is usually withheld from ‘high-risk’ patients with a history of thromboembolic, cardiovascular, or cerebrovascular disease, a patient group who would benefit greatly from a reduced blood loss.