Aims. We investigated the efficacy and safety profile of commonly used venous thromboembolism (VTE) prophylaxis agents following hip and knee arthroplasty. Methods. A systematic search of PubMed, Embase, Cochrane Library, Web of Science, and OrthoSearch was performed. Prophylaxis agents investigated were aspirin (< 325 mg and ≥ 325 mg daily), enoxaparin, dalteparin, fondaparinux, unfractionated heparin, warfarin, rivaroxaban, apixaban, and dabigatran. The primary efficacy outcome of interest was the risk of VTE, whereas the primary safety outcomes of interest were the risk of major bleeding events (MBE) and wound complications (WC). VTE was defined as the confirmed diagnosis of any deep vein thrombosis and/or pulmonary embolism. Network meta-analysis combining direct and indirect evidence was performed. Cluster rank analysis using the surface under cumulative ranking (SUCRA) was applied to compare each intervention group, weighing safety and efficacy outcomes. Results. Of 86 studies eligible studies, cluster rank analysis showed that aspirin < 325 mg daily (SUCRA-VTE 89.3%; SUCRA-MBE 75.3%; SUCRA-WC 71.1%), enoxaparin (SUCRA-VTE 55.7%; SUCRA-MBE 49.8%; SUCRA-WC 45.2%), and dabigatran (SUCRA-VTE 44.9%; SUCRA-MBE 52.0%; SUCRA-WC 41.9%) have an overall satisfactory efficacy and safety profile. Conclusion. We recommend the use of either aspirin < 325 mg daily, enoxaparin, or dabigatran for VTE prophylaxis following hip and knee arthroplasty. Cite this article: Bone Joint J 2024;106-B(9):924–934

Aims. The aim of this study is to compare the effectiveness and safety of thromboprophylactic treatments in patients undergoing primary total knee arthroplasty (TKA). Methods. Using nationwide medical registries, we identified patients with a primary TKA performed in Denmark between 1 January 2013 and 31 December 2018 who received thromboprophylactic treatment. We examined the 90-day risk of venous thromboembolism (VTE), major bleeding, and all-cause mortality following surgery. We used a Cox regression model to compute hazard ratios (HRs) with 95% confidence intervals (CIs) for each outcome, pairwise comparing treatment with dalteparin or dabigatran with rivaroxaban as the reference. The HRs were both computed using a multivariable and a propensity score matched analysis. Results. We identified 27,736 primary TKA patients who received thromboprophylactic treatment (rivaroxaban (n = 18,846); dalteparin (n = 5,767); dabigatran (n = 1,443); tinzaparin (n = 1,372); and enoxaparin (n = 308)). In the adjusted multivariable analysis and compared with rivaroxaban, treatment with dalteparin (HR 0.68 (95% CI 0.49 to 0.92)) or dabigatran (HR 0.31 (95% CI 0.13 to 0.70)) was associated with a decreased risk of VTE. No statistically significant differences were observed for major bleeding or all-cause mortality. The propensity score matched analysis yielded similar results. Conclusion. Treatment with dalteparin or dabigatran was associated with a decreased 90-day risk of VTE following primary TKA surgery compared with treatment with rivaroxaban. Cite this article: Bone Joint J 2021;103-B(10):1571–1577

Aims. Breast cancer survivors have known risk factors that might influence the results of total hip arthroplasty (THA) or total knee arthroplasty (TKA). This study evaluated clinical outcomes of patients with breast cancer history after primary THA and TKA. Methods. Our total joint registry identified patients with breast cancer history undergoing primary THA (n = 423) and TKA (n = 540). Patients were matched 1:1 based upon age, sex, BMI, procedure (hip or knee), and surgical year to non-breast cancer controls. Mortality, implant survival, and complications were assessed via Kaplan-Meier methods. Clinical outcomes were evaluated via Harris Hip Scores (HHSs) or Knee Society Scores (KSSs). Mean follow-up was six years (2 to 15). Results. Breast cancer patient survival at five years was 92% (95% confidence interval (CI) 89% to 95%) after THA and 94% (95% CI 92% to 97%) after TKA. Breast and non-breast cancer patients had similar five-year implant survival free of any reoperation or revision after THA (p ≥ 0.412) and TKA (p ≥ 0.271). Breast cancer patients demonstrated significantly lower survival free of any complications after THA (91% vs 96%, respectively; hazard ratio = 2 (95% CI 1.1 to 3.4); p = 0.017). Specifically, the rate of intraoperative fracture was 2.4% vs 1.4%, and venous thromboembolism (VTE) was 1.4% and 0.5% for breast cancer and controls, respectively, after THA. No significant difference was noted in any complications after TKA (p ≥ 0.323). Both breast and non-breast cancer patients experienced similar improvements in HHSs (p = 0.514) and KSSs (p = 0.132). Conclusion. Breast cancer survivors did not have a significantly increased risk of mortality or reoperation after primary THA and TKA. However, there was a two-fold increased risk of complications after THA, including intraoperative fracture and VTE. Cite this article: Bone Joint J 2024;106-B(4):365–371

The April 2023 Oncology Roundup³⁶⁰ looks at: Complete tumour necrosis after neoadjuvant chemotherapy defines good responders in patients with Ewing’s sarcoma; Monitoring vascularized fibular autograft: are radiographs enough?; Examining patient perspectives on sarcoma surveillance; The management of sacral tumours; Venous thromboembolism and major bleeding in the clinical course of osteosarcoma and Ewing’s sarcoma; Secondary malignancies after Ewing’s sarcoma: what is the disease burden?; Outcomes of distal radial endoprostheses for tumour reconstruction: a single centre experience over 15 years; Is anaerobic coverage during soft-tissue sarcoma resection needed?; Is anaerobic coverage during soft-tissue sarcoma resection needed?

The April 2024 Hip & Pelvis Roundup³⁶⁰ looks at: Impaction bone grafting for femoral revision hip arthroplasty with the Exeter stem; Effect of preoperative corticosteroids on postoperative glucose control in total joint replacement; Tranexamic acid in patients with a history of venous thromboembolism; Bisphosphonate use may be associated with an increased risk of periprosthetic hip fracture; A balanced approach: exploring the impact of surgical techniques on hip arthroplasty outcomes; A leap forward in hip arthroplasty: dual-mobility bearings reduce groin pain; A new perspective on complications: the link between blood glucose and joint infection risks.

The August 2023 Hip & Pelvis Roundup³⁶⁰ looks at: Using machine learning to predict venous thromboembolism and major bleeding events following total joint arthroplasty; Antibiotic length in revision total hip arthroplasty; Preoperative colonization and worse outcomes; Short stem cemented total hip arthroplasty; What are the outcomes of one- versus two-stage revisions in the UK?; To cement or not to cement? The best approach in hemiarthroplasty; Similar re-revisions in cemented and cementless femoral revisions for periprosthetic femoral fractures in total hip arthroplasty; Are hip precautions still needed?

Aims

The present study aimed to investigate whether patients with inflammatory bowel disease (IBD) undergoing joint arthroplasty have a higher incidence of adverse outcomes than those without IBD.

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.

Aims. The primary aim of this study was to assess whether non-fatal postoperative venous thromboembolism (VTE) within six months of surgery influences the knee-specific functional outcome (Oxford Knee Score (OKS)) one year after total knee arthroplasty (TKA). Secondary aims were to assess whether non-fatal postoperative VTE influences generic health and patient satisfaction at this time. Methods. A study of 2,393 TKAs was performed in 2,393 patients. Patient demographics, comorbidities, OKS, EuroQol five-dimension score (EQ-5D), and Forgotten Joint Score (FJS) were collected preoperatively and one year postoperatively. Overall patient satisfaction with their TKA was assessed at one year. Patients with VTE within six months of surgery were identified retrospectively and compared with those without. Results. A total of 37 patients (1.5%) suffered a VTE and were significantly more likely to have associated comorbidities of stroke (p = 0.026), vascular disease (p = 0.026), and kidney disease (p = 0.026), but less likely to have diabetes (p = 0.046). In an unadjusted analysis, patients suffering a VTE had a significantly worse postoperative OKS (difference in mean (DIM) 4.8 (95% confidence interval (CI) 1.6 to 8.0); p = 0.004) and EQ-5D (DIM 0.146 (95% CI 0.059 to 0.233); p = 0.001) compared with patients without a VTE. After adjusting for confounding variables VTE remained a significant independent predictor associated with a worse postoperative OKS (DIM -5.4 (95% CI -8.4 to -2.4); p < 0.001), and EQ-5D score (DIM-0.169 (95% CI -0.251 to -0.087); p < 0.001). VTE was not independently associated with overall satisfaction after TKA (odds ratio 0.89 (95% CI 0.35 to 2.07); p = 0.717). Conclusion. Patients who had a VTE within six months of their TKA had clinically significantly worse knee-specific outcome (OKS) and general health (EQ-5D) scores one year postoperatively, but the overall satisfaction with their TKA was similar to those patients who did not have a VTE. Cite this article: Bone Joint J 2021;103-B(7):1254–1260

Aims. Malignancy and surgery are risk factors for venous thromboembolism (VTE). We undertook a systematic review of the literature concerning the prophylactic management of VTE in orthopaedic oncology patients. Methods. MEDLINE (PubMed), EMBASE (Ovid), Cochrane, and CINAHL databases were searched focusing on VTE, deep vein thrombosis (DVT), pulmonary embolism (PE), bleeding, or wound complication rates. Results. In all, 17 studies published from 1998 to 2018 met the inclusion criteria for the systematic review. The mean incidence of all VTE events in orthopaedic oncology patients was 10.7% (1.1% to 27.7%). The rate of PE was 2.4% (0.1% to 10.6%) while the rate of lethal PE was 0.6% (0.0% to 4.3%). The overall rate of DVT was 8.8% (1.1% to 22.3%) and the rate of symptomatic DVT was 2.9% (0.0% to 6.2%). From the studies that screened all patients prior to hospital discharge, the rate of asymptomatic DVT was 10.9% (2.0% to 20.2%). The most common risk factors identified for VTE were endoprosthetic replacements, hip and pelvic resections, presence of metastases, surgical procedures taking longer than three hours, and patients having chemotherapy. Mean incidence of VTE with and without chemical prophylaxis was 7.9% (1.1% to 21.8%) and 8.7% (2.0% to 23.4%; p = 0.11), respectively. No difference in the incidence of bleeding or wound complications between prophylaxis groups was reported. Conclusion. Current evidence is limited to guide clinicians. It is our consensus opinion, based upon logic and deduction, that all patients be considered for both mechanical and chemical VTE prophylaxis, particularly in high-risk patients (pelvic or hip resections, prosthetic reconstruction, malignant diagnosis, presence of metastases, or surgical procedures longer than three hours). Additionally, the surgeon must determine, in each patient, if the risk of haemorrhage outweighs the risk of VTE. No individual pharmacological agent has been identified as being superior in the prevention of VTE events. Cite this article: Bone Joint J 2020;102-B(12)1743:–1751

Aims. The purpose of this study was to examine the efficacy and safety of carbazochrome sodium sulfonate (CSS) combined with tranexamic acid (TXA) on blood loss and inflammatory responses after primary total hip arthroplasty (THA), and to investigate the influence of different administration methods of CSS on perioperative blood loss during THA. Methods. This study is a randomized controlled trial involving 200 patients undergoing primary unilateral THA. A total of 200 patients treated with intravenous TXA were randomly assigned to group A (combined intravenous and topical CSS), group B (topical CSS), group C (intravenous CSS), or group D (placebo). Results. Mean total blood loss (TBL) in groups A (605.0 ml (SD 235.9)), B (790.9 ml (SD 280.7)), and C (844.8 ml (SD 248.1)) were lower than in group D (1,064.9 ml (SD 318.3), p < 0.001). We also found that compared with group D, biomarker level of inflammation, transfusion rate, pain score, and hip range of motion at discharge in groups A, B, and C were significantly improved. There were no differences among the four groups in terms of intraoperative blood loss (IBL), intramuscular venous thrombosis (IMVT), and length of hospital stay (LOS). Conclusion. The combined application of CSS and TXA is more effective than TXA alone in reducing perioperative blood loss and transfusion rates, inflammatory response, and postoperative hip pain, results in better early hip flexion following THA, and did not increase the associated venous thromboembolism (VTE) events. Intravenous combined with topical injection of CSS was superior to intravenous or topical injection of CSS alone in reducing perioperative blood loss. Cite this article: Bone Joint Res 2021;10(6):354–362

Aims. The aim of this study was to investigate the incidence, risk factors, and outcome of venous thromboembolism (VTE) following anterior cruciate ligament (ACL) reconstruction in a nationwide cohort. Patients and Methods. All ACL reconstructions, primary and revision, that were recorded in the Swedish Knee Ligament Register (SKLR) between 2006 and 2013 were linked with data from the Swedish National Board of Health and Welfare. The incidence of VTE was determined by entries between the day of surgery until 90 days postoperatively based on diagnosis codes and the prescription of anticoagulants. Risk factors, outcome, and the use of thromboprophylaxis were analyzed. Descriptive statistics with multivariate analysis were used to describe the findings. Results. The cohort consisted of 26 014 primary and revision ACL reconstructions. There were 89 deep venous thromboses (DVTs) and 12 pulmonary emboli (PEs) with a total of 95 VTEs (0.4 %). Six patients with a PE had a simultaneous DVT. The only independent risk factor for VTE was age greater than or equal to 40 years (odds ratio 2.31, 95% confidence interval 1.45 to 3.70; p < 0.001). Thromboprophylaxis was prescribed to 9461 patients (36%) and was equally distributed between those with and those without a VTE (37.9% vs 36.4%). All patient-reported outcome measures (PROMs) one and two years postoperatively were significantly lower in those with VTE. Conclusion. The incidence of VTE following ACL reconstruction is 0.4%, and the only significant risk factor is age. Patients with VTE had worse postoperative clinical outcome than patients without VTE. We recommend against the routine use of thromboprophylaxis, but it should be considered in older patients

Aims. To our knowledge, there is currently no information available about the rate of venous thromboembolism (VTE) or recommendations regarding chemoprophylaxis for patients whose lower limb is immobilized in a plaster cast. We report a retrospective case series assessing the rate of symptomatic VTE in patients treated with a lower limb cast. Given the complex, heterogeneous nature of this group of patients, with many risk factors for VTE, we hypothesized that the rate of VTE would be higher than in the general population. Patients and Methods. Patients treated with a lower limb cast between 2006 and 2018 were identified using plaster room records. Their electronic records and radiological reports were reviewed for details about their cast, past medical history, and any VTE recorded in our hospital within a year of casting. Results. There were 136 episodes of casting in 100 patients. The mean age was 55 years (22 to 91). The mean time in a cast was 45 days (five days to eight months). A total of 76 patients had neuropathy secondary to diabetes. No patient received chemical thromboprophylaxis while in a cast. One VTE (0.7% of casting episodes) was documented. This was confirmed by Doppler scan nine days after removing the cast. Conclusion. The frequency of VTE was higher than that of the general population (0.05%); this is most likely attributable to our patients’ apparent increase in VTE risk as suggested by The National Institute for Health and Care Excellence (NICE). These findings suggest that thromboprophylaxis is not routinely indicated in patients who undergo immobilization of the lower limb in a cast, although the risks of VTE should be assessed. While the cast itself does not pose an increased risk, other pathologies, such as active cancer, mean that each individual case needs to be considered on their merit. Cite this article: Bone Joint J 2019;101-B:691–694

Aims. As the first wave of the COVID-19 pandemic began to dip, restarting elective orthopaedics became a challenge. Protocols including surgery at ‘green’ sites, self-isolation for 14 days, and COVID-19 testing were developed to minimize the risk of transmission. In this study, we look at risk effects of 14-day self-isolation on the incidence of venous thromboembolism (VTE) in our green site hospital among patients undergoing total joint replacement (TJR). Methods. This retrospective cohort study included 50 patients who underwent TJR. Basic demographic data was collected including, age, sex, American Society of Anesthesiologists (ASA) grade, body mass index (BMI), type of surgery, and complications at two and four weeks. Univariate and multivariate analysis were used to identify risk factors associated with an increased risk of VTE. Results. A total of 50 patients were included in our study, with 24 males and 26 females. The mean age was 67.86 (SD 11.803). Overall, 8% of patients suffered a VTE complication; symptomatic non-fatal pulmoary embolism was confirmed in 6% of patients (n = 3) as an inpatient, and symptomatic deep vein thrombosis was diagnosed in 2% of patients (n = 1) within two weeks of their operation. All patients were found to be female (p < 0.001), had a BMI > 30 (p = 0.317), and were immobile prior to their operation using walking aids (p = 0.016). Conclusion. The incidence we report is much higher than the reported incidence in the literature, which we believe is related to the 14-day self-isolation period and immobility prior to their operation. We recommend that all patients undergoing TJR that require a period of self-isolation, are pre-assessed prior to self-isolation for their risk of VTE, potentially using mechanical and chemical prophylaxis to reduce the likelihood of developing VTE. Cite this article: Bone Jt Open 2020;1-12:751–756

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. Methods. TRAC-24 was a prospective, phase IV, single centre, open label, parallel group, randomized controlled trial (RCT) involving patients undergoing primary unilateral elective THA. The primary outcome measure was the indirect calculated blood loss (IBL) at 48 hours. The patients were randomized into three groups. Group 1 received 1 g intravenous (IV) TXA at the time of surgery and an additional oral regime for 24 hours postoperatively, group 2 only received the intraoperative dose, and group 3 did not receive any TXA. Results. A total of 534 patients were randomized, with 233 in group 1, 235 in group 2, and 66 in group 3; 92 patients (17.2%) were considered high-risk. The mean IBL did not differ significantly between the two intervention groups (848.4 ml (SD 463.8) for group 1, and 843.7 ml (SD 478.7) for group 2; mean difference -4.7 ml (95% confidence interval -82.9 to 92.3); p = 0.916). No differences in mortality or incidence of VTE were observed between any group. Conclusion. The addition of oral TXA for 24 hours postoperatively does not reduce blood loss beyond that achieved with a single 1 g IV perioperative dose alone. There may be a clinically relevant difference in patients with a normal BMI, which warrants further investigation. Critically, there were no safety issues in patients with a history of thromboembolic, cardiovascular, or cerebrovascular disease. Cite this article: Bone Joint J 2021;103-B(7):1197–1205

Aims. We studied the safety and efficacy of multimodal thromboprophylaxis in patients with a history of venous thromboembolism (VTE) who undergo total hip arthroplasty (THA) within the first 120 postoperative days, and the mortality during the first year. Multimodal prophylaxis includes discontinuation of procoagulant medications, VTE risk stratification, regional anaesthesia, an intravenous bolus of unfractionated heparin prior to femoral preparation, rapid mobilization, the use of pneumatic compression devices, and chemoprophylaxis tailored to the patient’s risk of VTE. Methods. Between 2004 to 2018, 257 patients with a proven history of VTE underwent 277 primary elective THA procedures by two surgeons at a single institution. The patients had a history of deep vein thrombosis (DVT) (186, 67%), pulmonary embolism (PE) (43, 15.5%), or both (48, 17.5%). Chemoprophylaxis included aspirin (38 patients), anticoagulation (215 patients), or a combination of aspirin and anticoagulation (24 patients). A total of 50 patients (18%) had a vena cava filter in situ at the time of surgery. Patients were followed for 120 days to record complications, and for one year to record mortality. Results. Postoperative VTE was diagnosed in seven patients (2.5%): DVT in five, and PE with and without DVT in one patient each. After hospitalization, three patients required readmiss-ion for evacuation of a haematoma, one for wound drainage, and one for monitoring of an elevated international normalized ratio (INR). Seven patients died (2.5%). One patient died five months postoperatively of a PE during open thrombectomy. She had discontinued anticoagulation. One patient died of a haemorrhagic stroke while receiving Coumadin. PE or bleeding was not suspected in the remaining five fatalities. Conclusion. Multimodal prophylaxis is safe and effective in patients with a history of VTE. Postoperative anticoagulation should be prudent as very few patients developed VTE (2.5%) or died of suspected or confirmed PE. Mortality during the first year was mostly unrelated to either VTE or bleeding. Cite this article: Bone Joint J 2020;102-B(7 Supple B):71–77

Abstract. Introduction. Neck of femur (NOF) fracture patients are at risk of developing venous thromboembolisms (VTE). VTE risks could be reduced by adhering to the National Institute for Health and Care Excellence (NICE) recommendation for 1 month of prophylaxis with low molecular weight heparin. This audit aimed to assess and improve local compliance to national guidelines on VTE prophylaxis in NOF fracture patients following discharge. Methods. A retrospective consecutive case series of all NOF fractures treated at our institution from May – July 2021 was conducted. Those not eligible for outpatient VTE prophylaxis were excluded (anticoagulated for other indications, completed prophylactic course in hospital, inpatient death, pharmacological prophylaxis contraindicated). The agent and duration of VTE prophylaxis, and the occurrence of clinically significant VTE or bleeds were recorded. A re-audit was conducted in March 2022. Results. From May – July 2021, only 1/65 (1.5%) patient was discharged on a VTE prophylaxis regime consistent with NICE guidelines (1 enoxaparin, 56 rivaroxaban, 6 apixaban; 58 35-day course, 5 28-day course). A quick-guide document summarising the standard inpatient and outpatient VTE prophylaxis regimes for various orthopaedic indications was designed and widely disseminated. In March 2022, 30/34 (88.2%) patients were discharged with enoxaparin and 24/34 (70.6%) received a 28-day course. There were no cases of clinically significant VTE or bleeds in both cycles. Conclusion. Local compliance to national guidelines improved significantly with the implementation of a standardised VTE prophylaxis protocol. Our quick-guide document is a reproducible way of communicating consensus and ensuring consistency within a department

Venous thromboembolism (VTE) is a preventable cause of morbidity and mortality in patients undergoing elective hip arthroplasty surgery. The balance of post-operative VTE prophylaxis and risk of post-operative haemorrhage remains at the forefront of surgeon's mind. The National Institute for Clinical Excellence (NICE) has altered their prophylaxis guidance in the setting of total hip arthroplasty (THA). The aim of this study was to present the VTE incidence in 8,890 patients who underwent total hip arthroplasty between January 1997 and March 2018 with Aspirin as the primary agent for pharmacological thromboprophylaxis. Analysis of prospective data collection from consecutive patients undergoing THA was performed with the incidence of deep vein thrombosis (DVT) and pulmonary embolism (PE) occurring within 6 months of the index operation as the primary outcome measure. 90-day all-cause mortality of this cohort of patients was also analysed. 8890 patients were reviewed. This included 7235 primary, 224 complex primary and 1431 revision cases. The incidence of DVT was 0.64% after elective THA and the incidence of PE was 0.54%. There was no difference in the incidence between primary and revision cases. The 90-day all-cause mortality was 0.88%. Cardiovascular and respiratory disease were the main causes of death following surgery. Only 0.03% of deaths (n= 3) within 90 days of index surgery were due to VTE. Our results support the use of aspirin as an effective form of prophylaxis against VTE following THA. It is not associated with an increased incidence in symptomatic DVT, PE or death compared to other published studies. The fact that it is inexpensive, readily available, requires no monitoring and does not pose an increased risk of bleeding are other attractive advantages of using aspirin for VTE prophylaxis

Abstract. Aims. The association between body mass index (BMI) and venous thromboembolism (VTE) is well studied, but remains unclear in the literature. We aimed to determine whether morbid obesity (BMI≥40) was associated with increased risk of VTE following total knee arthroplasty (TKA) or unicompartmental knee arthroplasty (UKA), compared to those of BMI<40. Methods. Between January 2016 and December 2020, our institution performed 4506 TKAs and 449 UKAs. 450 (9.1%) patients had a BMI≥40. CT pulmonary angiography (CTPA) for suspected pulmonary embolism (PE) and ultrasound scan for suspected proximal deep vein thrombosis (DVT) were recorded up to 90 days post-operatively. Results. When comparing those of BMI<40 to those with BMI≥40, there was no difference in incidence of PE (1.0% vs 1.1%, p=0.803) or proximal DVT (0.4% vs 0.2%, p=0.645). There was no difference in number of ultrasound scans ordered (p=0.668), or number of CTPAs ordered for those with a BMI≥40 (p=0.176). The percentage of patients with a confirmed PE or proximal DVT were 24.2% and 3.9% respectively in the BMI<40 group, compared to 20.0% (p=0.804) and 2.3% (p=0.598) in the BMI≥40 group. Conclusion. Morbid obesity was not associated with increased risk of PE or proximal DVT within 90 days of TKA or UKA. Overall, 76.3% of CTPAs and 96.2% of ultrasound scans were negative. Increasing the threshold for VTE investigation would reduce the rate of negative investigations. Establishing more effective risk stratification protocols, to guide investigation, would likely reduce unnecessary imaging

Following the publication in 2007 of the guidelines from the National Institute for Health and Clinical Excellence (NICE) for prophylaxis against venous thromboembolism (VTE) for patients undergoing surgery, concerns were raised by British orthopaedic surgeons as to the appropriateness of the recommendations for their clinical practice. In order to address these concerns NICE and the British Orthopaedic Association agreed to engage a representative panel of orthopaedic surgeons in the process of developing expanded VTE guidelines applicable to all patients admitted to hospital. The functions of this panel were to review the evidence and to consider the applicability and implications in orthopaedic practice in order to advise the main Guideline Development Group in framing recommendations. The panel considered both direct and indirect evidence of the safety and efficacy, the cost-effectiveness of prophylaxis and its implication in clinical practice for orthopaedic patients. We describe the process of selection of the orthopaedic panel, the evidence considered and the contribution of the panel to the latest guidelines from NICE on the prophylaxis against VTE, published in January 2010

We report an audit of 208 patients with a mean age of 39 years (16 to 65) attending the Orthopaedic Assessment Unit at the Wellington Hospital between January 2006 and December 2007 with an injury of the tendo Achillis requiring immobilisation in a cast. Information on assessment of venous thromboembolism (VTE) risk, prophylactic measures and VTE events for all patients was obtained from the medical records. A VTE risk factor was documented in the records of three (1%) patients. One of the 208 patients received aspirin prophylaxis; none received low molecular weight heparin. In all, 13 patients (6.3%, 95% confidence interval 3.4 to 10.5) developed symptomatic VTE during immobilisation in a cast, including six with a distal deep-vein thrombosis (DVT), four with a proximal DVT, and three with a confirmed pulmonary embolus. This incidence of symptomatic VTE is similar to that reported following elective hip replacement. We propose that consideration is given to VTE prophylaxis during prolonged immobilisation of the lower limbs in a cast, to ensure that the same level of protection is provided as for patients undergoing elective hip replacement

The number of arthroplasties being performed increases each year. Patients undergoing an arthroplasty are at risk of venous thromboembolism (VTE) and appropriate prophylaxis has been recommended. However, the optimal protocol and the best agent to minimise VTE under these circumstances are not known. Although many agents may be used, there is a difference in their efficacy and the risk of bleeding. Thus, the selection of a particular agent relies on the balance between the desire to minimise VTE and the attempt to reduce the risk of bleeding, with its undesirable, and occasionally fatal, consequences. Acetylsalicylic acid (aspirin) is an agent for VTE prophylaxis following arthroplasty. Many studies have shown its efficacy in minimising VTE under these circumstances. It is inexpensive and well-tolerated, and its use does not require routine blood tests. It is also a ‘milder’ agent and unlikely to result in haematoma formation, which may increase both the risk of infection and the need for further surgery. Aspirin is also unlikely to result in persistent wound drainage, which has been shown to be associated with the use of agents such as low-molecular-weight heparin (LMWH) and other more aggressive agents. The main objective of this review was to summarise the current evidence relating to the efficacy of aspirin as a VTE prophylaxis following arthroplasty, and to address some of the common questions about its use. . There is convincing evidence that, taking all factors into account, aspirin is an effective, inexpensive, and safe form of VTE following arthroplasty in patients without a major risk factor for VTE, such as previous VTE. Cite this article: Bone Joint J 2017;99-B:1420–30

Thrombelastography (TEG) is a point-of-care tool that can measure clot formation and breakdown using a whole blood sample. We have previously used serial TEG analysis to define hypercoagulability and increased venous thromboembolism (VTE) risk following a major fracture requiring surgical treatment. Additionally, we have used serial TEG analysis to quantify the prolonged hypercoagulable state and increased VTE risk that ensues following a hip fracture. Recently developed cartridge-based platelet mapping (PLM) using TEG analysis can be used to activate platelets at either the adenosine diphosphate (ADP) receptor or at the Thromboxane A2 (AA) receptor, in order to evaluate clot strength when platelets are activated only through those specific receptors. This study aim was to evaluate platelet contribution to hypercoagulability, in order to identify potential therapeutic targets for VTE prevention. We hypothesized that there would be a platelet-predominant contribution to hypercoagulability following a hip fracture. Patients aged 50 years or older with a hip fracture treated surgically were enrolled in this prospective cohort study. Exclusion criteria were: prior history of VTE, active malignancy, or pre-injury therapeutic dose anticoagulation. Serial TEG and PLM analyses were performed at admission, post-operative day (POD) 1, 3, 5, 7 and at 2-, 4-, 6- and 12-weeks post-operatively. All patients received thromboprophylaxis with low molecular weight heparin (LMWH) for 28 days post-operatively. Hypercoagulability was defined as maximal amplitude (MA; a measure of clot strength) over 65mm based on TEG analysis. Independent samples t-tests were used to compare MA values with this previously established threshold and a mixed effects linear regression model was used to compare MA values over time. Independent samples t-tests and Chi-sqaured analyses were used to compare between the surgical fixation and arthroplasty groups. Forty-six patients with an acute hip fracture were included, with a mean age of 77.1 (SD = 10.6) years, with 61% (N=11) being female. Twenty-six were treated with arthroplasty (56.5%), while the remainder underwent surgical fixation of their hip fractures. TEG analysis demonstrated post-operative hypercoagulability (mean MA over 65mm) at all follow-up timepoints until 12-weeks. PLM identified a platelet-mediated hypercoagulable state based on elevated ADP-MA and AA-MA, with more pronounced platelet contribution demonstrated by the AA pathway. Patients treated with arthroplasty had significantly increased AA-MA compared with ADP-MA at POD 3 and at the 12-week follow-up. Thrombelastography can be used to identify hypercoagulability and increased risk for VTE following a hip fracture. Platelet mapping analysis from this pilot study suggests a platelet-mediated hypercoagulable state that may benefit from thromboprophylaxis using an anti-platelet agent that specifically targets the AA platelet activation pathway, such as acetylsalicylic acid (ASA). This research also supports differences in hypercoagulability between patients treated with arthroplasty compared to those who undergo fracture fixation

Prolonged bedrest in hospitalized patients is a major risk factor for venous thromboembolism (VTE), especially in high risk patients with hip fracture. Thrombelastography (TEG) is a whole blood viscoelastic hemostatic assay with evidence that an elevated maximal amplitude (MA), a measure of clot strength, is predictive of VTE in orthopaedic trauma patients. The objective of this study was to compare the TEG MA parameter between patients with hip fracture who were more mobile post-operatively and discharged from hospital early to patients with hip fracture with reduced mobility and prolonged hospitalizations post-operatively. In this prospective cohort study, TEG analysis was performed in patients with hip fracture every 24-hours from admission until post-operative day (POD) 5, then at 2- and 6-weeks post-operatively. Hypercoagulability was defined by MA > 65. Patients were divided into an early (within 5-day) and late (after 5-day) discharge group, inpatient at 2-weeks group, and discharge to MSK rehabilitation (MSK rehab), and long term care (LTC) groups. Two-sample t-test was used to analyze differences in MA between the early discharge and less mobile groups. All statistical tests were two-sided, and p-values < 0.05 were considered statistically significant. In total, 121 patients with a median age of 81.0 were included. Patients in the early discharge group (n=15) were younger (median age 64.0) and more likely to ambulate without gait aids pre-injury (86.7%) compared to patients in the late discharge group (n=105), inpatients at 2-weeks (n=48), discharged to MSK rehab (n=30), and LTC (n=20). At two weeks post-operative, the early discharge group was significantly less hypercoagulable (MA=68.9, SD 3.0) compared to patients in the other four groups. At 6-weeks post-operative, the early discharge group was the only group to demonstrate a trend towards mean MA below the MA > 65 hypercoagulable threshold (MA=64.4, p=0.45). Symptomatic VTE events were detected in three patients (2.5%) post-operatively. All three patients had hospitalizations longer than five days after surgery. In conclusion, our analysis of hypercoagulability secondary to reduced post-operative mobility demonstrates that patients with hip fracture who were able to mobilize independently sooner after hip fracture surgery, have a reduced peak hypercoagulable state. In addition, there is a trend towards earlier return to normal coagulation status as determined by the TEG MA parameter. Post-operative mobility status may play a role in determining individualized duration of thromboprophylaxis following hip fracture surgery. Future studies comparing TEG to clinically validated mobility tools may more closely evaluate the contribution of venous stasis due to reduced mobility on hypercoagulation following hip fracture surgery

Prolonged bedrest in hospitalized patients is a major risk factor for venous thromboembolism (VTE), especially in high risk patients with hip fracture. Thrombelastography (TEG) is a whole blood viscoelastic hemostatic assay with evidence that an elevated maximal amplitude (MA), a measure of clot strength, is predictive of VTE in orthopaedic trauma patients. The objective of this study was to compare the TEG MA parameter between patients with hip fracture who were more mobile post-operatively and discharged from hospital early to patients with hip fracture with reduced mobility and prolonged hospitalizations post-operatively. In this prospective cohort study, TEG analysis was performed in patients with hip fracture every 24-hours from admission until post-operative day (POD) 5, then at 2- and 6-weeks post-operatively. Hypercoagulability was defined by MA > 65. Patients were divided into an early (within 5-day) and late (after 5-day) discharge group, inpatient at 2-weeks group, and discharge to MSK rehabilitation (MSK rehab), and long term care (LTC) groups. Two-sample t-test was used to analyze differences in MA between the early discharge and less mobile groups. All statistical tests were two-sided, and p-values < 0.05 were considered statistically significant. In total, 121 patients with a median age of 81.0 were included. Patients in the early discharge group (n=15) were younger (median age 64.0) and more likely to ambulate without gait aids pre-injury (86.7%) compared to patients in the late discharge group (n=105), inpatients at 2-weeks (n=48), discharged to MSK rehab (n=30), and LTC (n=20). At two weeks post-operative, the early discharge group was significantly less hypercoagulable (MA=68.9, SD 3.0) compared to patients in the other four groups. At 6-weeks post-operative, the early discharge group was the only group to demonstrate a trend towards mean MA below the MA > 65 hypercoagulable threshold (MA=64.4, p=0.45). Symptomatic VTE events were detected in three patients (2.5%) post-operatively. All three patients had hospitalizations longer than five days after surgery. In conclusion, our analysis of hypercoagulability secondary to reduced post-operative mobility demonstrates that patients with hip fracture who were able to mobilize independently sooner after hip fracture surgery, have a reduced peak hypercoagulable state. In addition, there is a trend towards earlier return to normal coagulation status as determined by the TEG MA parameter. Post-operative mobility status may play a role in determining individualized duration of thromboprophylaxis following hip fracture surgery. Future studies comparing TEG to clinically validated mobility tools may more closely evaluate the contribution of venous stasis due to reduced mobility on hypercoagulation following hip fracture surgery

Objectives. Venous thromboembolism (VTE) is a major potential complication following orthopaedic surgery. Subcutaneously administered enoxaparin has been used as the benchmark to reduce the incidence of VTE. However, concerns have been raised regarding the long-term administration of enoxaparin and its possible negative effects on bone healing and bone density with an increase of the risk of osteoporotic fractures. New oral anticoagulants such as rivaroxaban have recently been introduced, however, there is a lack of information regarding how these drugs affect bone metabolism and post-operative bone healing. Methods. We measured the migration and proliferation capacity of mesenchymal stem cells (MSCs) under enoxaparin or rivaroxaban treatment for three consecutive weeks, and evaluated effects on MSC mRNA expression of markers for stress and osteogenic differentiation. Results. We demonstrate that enoxaparin, but not rivaroxaban, increases the migration potential of MSCs and increases their cell count in line with elevated mRNA expression of C-X-C chemokine receptor type 4 (CXCR4), tumor necrosis factor alpha (TNFα), and alpha-B-crystallin (CryaB). However, a decrease in early osteogenic markers (insulin-like growth factors 1 and 2 (IGF1, IGF2), bone morphogenetic protein2 (BMP2)) indicated inhibitory effects on MSC differentiation into osteoblasts caused by enoxaparin, but not by rivaroxaban. Conclusions. Our findings may explain the adverse effects of enoxaparin treatment on bone healing. Rivaroxaban has no significant impact on MSC metabolism or capacity for osteogenic differentiation in vitro. Cite this article: Dr H. Pilge. Enoxaparin and rivaroxaban have different effects on human mesenchymal stromal cells in the early stages of bone healing. Bone Joint Res 2016;5:95–100. DOI: 10.1302/2046-3758.53.2000595

Venous thromboembolism (VTE) remains an immediate threat to patients following total hip and knee replacement. While there is a strong consensus that steps should be taken to minimise the risk to patients by utilising some forms of prophylaxis for the vast majority of patients, the methods utilised have been extremely variable. Clinical practice guidelines (CPGs) have been published by various professional organisations for over 25 years to provide recommendations to standardise VTE prophylaxis. Historically, these recommendations have varied widely depending in underlying assumptions, goals, and methodology of the various groups. This effort has previously been exemplified by the American College of Chest Physicians (ACCP) and the American Academy of Orthopaedic Surgeons (AAOS). The former group of medical specialists targeted minimising venographically proven deep vein thrombosis (DVT) (the vast majority of which are asymptomatic) as their primary goal prior to 2012. The latter group of surgeons targeted minimising symptomatic VTE. As a result prior to 2012, the recommendations of the two groups were widely divergent. In the past year, both groups have reassessed the current literature with the principal goals of minimising symptomatic VTE events and bleeding complications. As a result, for the first time the CPGs of these two major subspecialty organisations are in close agreement

Major orthopaedic fractures are an independent risk factor for the development of venous thromboembolism (VTE), which are significant causes of preventable morbidity and mortality in trauma patients. Despite thromboprophylaxis, patients who sustain a pelvic or acetabular fracture (PA) continue to have high rates of VTE (12% incidence). Thrombelastography (TEG) is a whole-blood, point-of-care test which provides an overview of the clotting process. Maximal amplitude (MA), from TEG analysis, is the measure of clot strength and values ≥65mm have been used to quantify hypercoagulability and increased VTE risk. Therefore, the primary aim was to use serial TEG analysis to quantify the duration of hypercoagulability, following surgically treated PA fractures. This is a single centre, prospective cohort study of adult patients 18 years or older with surgically treated PA fractures. Consecutive patients were enrolled from a Level I trauma centre and blood draws were taken over a 3-month follow-up period for serial TEG analysis. Hypercoagulability was defined as MA ≥65mm. Exclusion criteria: bleeding disorders, active malignancy, current therapeutic anticoagulation, burns (>20% of body surface) and currently, or expecting to become pregnant within study timeframe. Serial TEG analysis was performed using a TEG6s hemostasis analyzer (Haemonetics Corp.) upon admission, pre-operatively, on post-operative day (POD) 1, 3, 5, 7 (or until discharged from hospital, whichever comes sooner), then in follow-up at 2-, 4-, 6-weeks and 3-months post-operatively. Patients received standardized thromboprophylaxis with low molecular weight heparin for 28 days post-operatively. VTE was defined as symptomatic DVT or PE, or asymptomatic proximal DVT, and all participants underwent a screening post-operative lower extremity Doppler ultrasound on POD3. Descriptive statistics were used to determine the association between VTE events and MA values. For the primary outcome measure, the difference between the MA threshold value (≥65mm) and serial MA measures, were compared using one-sided t-tests (α=0.05). Twenty-eight patients (eight females, 29%) with a mean age of 48±18 years were included. Acetabular fractures were sustained by 13 patients (46%), pelvic fractures by 14 patients (50%), and one patient sustained both. On POD1, seven patients (25%) were hypercoagulable, with 21 patients (78%) being hypercoagulable by POD3, and 17 patients (85%) by POD5. The highest average MA values (71.7±3.9mm) occurred on POD7, where eight patients (89%) were hypercoagulable. At 2-weeks post-operatively, 16 patients (94%) were hypercoagulable, and at four weeks, when thromboprophylaxis was discontinued, six patients (40%) remained hypercoagulable. Hypercoagulability persisted for five patients (25%) at 6-weeks and for two patients (10%) by three months. There were six objectively diagnosed VTE events (21.4%), five were symptomatic, with a mean MA value of 69.3mm±4.3mm at the time of diagnosis. Of the VTE events, four occurred in participants with acetabular fractures (three male, 75%) and two in those with pelvic fractures (both males). At 4-weeks post-operatively, when thromboprophylaxis is discontinued, 40% of patients remained hypercoagulable and likely at increased risk for VTE. At 3-months post-operatively, 10% of the cohort continued to be hypercoagulable. Serial TEG analysis warrants further study to help predict VTE risk and to inform clinical recommendations following PA fractures

Surgical management for acute or impending pathologic fractures in metastatic bone disease (MBD) places patients at high-risk for post-operative venous thromboembolism (VTE). Due to the combination of malignancy, systemic cancer treatment, and surgical treatment, VTE-risk is increased 7-fold in patients with MBD compared to non-cancer patients undergoing the same procedure. The extent and duration of post-operative hypercoagulability in patients with MBD remains unknown and thromboprophylaxis guidelines were developed for non-cancer patients, limiting their applicability to address the elevated VTE-risk in cancer patients. Thrombelastography (TEG) analysis is a point-of-care test that measures clot formation, stabilization, and lysis in whole blood samples. The TEG parameter, maximal amplitude (MA), indicates clot strength and the threshold of ≥65 mm has been used to define hypercoagulability and predict VTE events in non-cancer patients requiring orthopaedic surgery. Therefore, this study aims to quantify the extent and duration of post-operative hypercoagulability in patients with MBD using serial TEG analysis. Consecutive adults (≥18 years) with MBD who required orthopaedic surgery for acute or impending pathologic fractures were enrolled into this single-centre, prospective cohort study. Serial TEG analysis was performed onsite using a TEG®6s haemostasis analyzer (Haemonetics Corporation, Boston, MA) on whole blood samples collected at seven timepoints: pre-operatively; on post-operative day (POD) 1, 3, and 5; and at 2-, 6-, and 12-weeks post-operatively. Hypercoagulability was defined as MA ≥65 mm. Participants received standardized thromboprophylaxis for four weeks and patient-reported compliance with thromboprophylaxis was recorded. VTE was defined as symptomatic DVT or PE, or asymptomatic proximal DVT, and all participants underwent a screening post-operative lower extremity Doppler ultrasound on POD3. Descriptive statistics were performed and difference between pre-operative MA values of participants with VTE versus no VTE was evaluated using Student's t-test (p≤0.05). Twenty-one participants (10 female; 47.6%) with a mean age of 70 ± 12 years were enrolled. Nine different primary cancers were identified amongst participants, with breast (23.8%), colorectal (19.0%), and lung cancer (14.3%) most frequently reported. Most participants (57.1%) were hypercoagulable pre-operatively, and nearly half remained hypercoagulable at 6- and 12-weeks post-operatively (47.1 and 46.7%, respectively). VTE occurred in 5 patients (23.8%) and mean MA was 68.1 ± 4.6 mm at the time of diagnosis. Mean pre-operative MA values were significantly higher (p=0.02) in patients who experienced VTE (68.9 ± 3.5 mm) compared to those who did not (62.7 ± 6.5 mm). VTE incidence was highest in the first week post-operatively, during which time four VTE events (80%) occurred. The proportion of patients in a hypercoagulable state increased at three consecutive timepoints, beginning on POD3 (85.0%), increasing on POD5 (87.5%), and peaking at 2-weeks post-operatively (88.9%). Current thromboprophylaxis guidelines do not consider cancer-associated risk factors that contribute to increased VTE incidence and prescription duration may be inadequate to address prolonged post-operative hypercoagulability in patients with MBD. The high rate of VTE events observed and sustained hypercoagulable state indicate that thromboprophylaxis may be prematurely terminated while patients remain at high risk for VTE. Therefore, extending thromboprophylaxis duration beyond 4-weeks post-operatively in patients with MBD warrants further investigation

Considerable debate exists regarding which agent(s) should be preferred for venous thromboembolism (VTE) chemical prophylaxis following joint replacement. We assessed the practice of surgeons regarding VTE chemical prophylaxis for primary THR and TKR, pre and post issuing of updated NICE guidance in 2018. A survey, circulated through the British Hip Society and regional trainee networks/collaboratives, was completed by 306 UK surgeons at 187 units. VTE chemical prophylaxis prescribing patterns for surgeons carrying out primary THR (n=258) and TKR (n=253) in low-risk patients were assessed post publication of 2018 NICE recommendations. Prescribing patterns before and after the NICE publication were subsequently explored. Questions were also asked about surgeon equipoise for participation in future RCTs. Following the new guidance, 34% (n=87) used low-molecular weight heparin (LMWH) alone, 33% (n=85) aspirin (commonly preceded by LMWH), and 31% (n=81) direct oral anticoagulants (DOACs: with/without preceding LMWH) for THR. For TKR, 42% (n=105) used aspirin (usually monotherapy), 31% (n=78) LMWH alone, and 27% (n=68) DOAC (with/without preceding LMWH). NICE guidance changed the practice of 34% of hip and 41% of knee surgeons, with significantly increased use of aspirin preceded by LMWH for THR (before=25% vs. after=73%;p<0.001), and aspirin for TKR (before=18% vs. after=84%;p<0.001). Significantly more regimens were NICE guidance compliant after the 2018 update for THR (before=85.7% vs. after=92.6%;p=0.011) and TKR (before=87.0% vs. after=98.8%;p<0.001). Support from surgeons for future RCTs was dependent on the clinical question, ranging from 48% participation in trials (effectiveness of aspirin vs. a DOAC) to 79% (effectiveness of 14 days LMWH vs. 28 days LMWH). Over one-third of surveyed surgeons changed their VTE chemical prophylaxis in response to 2018 NICE recommendations, with more THR and TKR surgeons now compliant with latest NICE guidance. The major change in practice was an increased use of aspirin for VTE chemical prophylaxis. Furthermore, there is an appetite amongst UK surgeons for participating in future RCTs, with a trial comparing standard versus extended duration LMWH likely feasible in current practice

Introduction. Venous thromboembolism (VTE), defined as either pulmonary embolism (PE) or deep venous thrombosis (DVT), is a rare, but serious complication following total hip arthroplasty (THA). Current VTE guidelines recommend pharmacologic agents with or without intermittent pneumatic compression devices (IPCDs). At our institution, both 81mg aspirin (ASA) twice a day (BID) and portable IPCDs were prescribed to THA patients at standard risk for VTE. The aim of this study is to determine if discontinuing the use of portable outpatient IPCDs is safe and does not increase the rate of VTE in patients undergoing THA. Methods. A retrospective review of 1,825 consecutive THA cases was conducted identifying patients with a VTE 90-days postoperatively. Patients were divided into two separate consecutive cohorts. Cohort one consisted of THA patients who received outpatient IPCDs for a period of 14 days (control). Cohort two consisted of THA patients without outpatient IPCDs (experimental). Patients were non-randomized to 81mg ASA BID for 28 days for VTE chemoprophylaxis. An interim power analysis was performed to determine the proper sample size. Results. A total of 748 patients were discharged with outpatient IPCDs while 1,077 patients were discharged without IPCDs. There were no VTE events found in control group (0%). The total VTE rate of the experimental group was 0.2% (2 PE and 1 DVT). There was no statistical difference between these rates (p=0.24). A binary logistic regression did not detect any significant associations for any VTE outcomes even after accounting for demographic differences. Conclusion. Our findings suggest that discontinued use of outpatient portable IPCDs is safe and does not increase the rate of VTE in standard risk patients undergoing THA while using 81mg ASA BID as VTE prophylaxis

Venous thromboembolism (VTE) is a serious complication after total hip and knee arthroplasty. There is still no consensus regarding the best mode of thromboprophylaxis after lower limb arthroplasty. The aim of this study was to ascertain the efficacy, safety profile and rate of adverse thromboembolic events of aspirin as extended out of hospital pharmacological anticoagulation for elective primary total hip and knee arthroplasty patients and whether these rates were comparable with published data for low molecular weight heparin (LMWH). Data was extracted from a prospective hospital acquired thromboembolism (HAT) database. The period of study was from 1st Jan 2013-31st Dec 2016 and a total of 6078 patients were treated with aspirin as extended thromboprophylaxis after primary total hip and knee arthroplasty. The primary outcome measure of deep vein thrombosis and pulmonary embolism within 90 days postoperatively was 1.11%. The secondary outcome rates of wound infection, bleeding complications, readmission rate and mortality were comparable to published results after LMWH use. The results of this study clearly show that Aspirin, as part of a multimodal thromboprophylactic regime, is an effective and safe regime in preventing VTE with respect to risk of DVT or PE when compared to LMWH. It is a cheaper alternative to LMWH and has associated potential cost savings

Background. Few studies have compared aspirin with DOACs (direct oral anticoagulants = direct thrombin inhibitors and factor Xa inhibitors) for venous thromboembolism (VTE) prophylaxis following total hip and knee replacement (THR and TKR). We assessed the efficacy and safety of aspirin compared with DOACs for VTE prophylaxis following THR and TKR using the world's largest joint replacement registry. Methods. We studied the National Joint Registry linked to English hospital inpatient episodes for 218,650 THR and TKR patients. Patients receiving aspirin were matched separately to (1) direct thrombin inhibitors, and (2) factor Xa inhibitors using propensity scores. Outcomes assessed at 90 days included VTE, length of stay, and adverse events. Results. Following THR, the risk of VTE was significantly lower in patients receiving direct thrombin inhibitors (0.44%; odds ratio (OR)=0.69, 95% confidence interval (CI)=0.55–0.87, p=0.002) and factor Xa inhibitors (0.37%; OR=0.63, CI=0.47–0.85, p=0.003) compared with aspirin (0.63%). Following THR, direct thrombin inhibitors (coefficient=−0.37, CI=−0.43 to −0.31, p<0.001) and factor Xa inhibitors (coefficient=−0.80, CI=−0.87 to −0.74, p<0.001) reduced length of stay compared with aspirin. Similar findings for both outcomes were observed following TKR. Compared with aspirin, DOACs did not increase the risk of short-term revision surgery; reoperation; major haemorrhage; wound disruption; surgical site infection; and mortality. Conclusions. Following THR and TKR, the risk of VTE was lower in patients receiving DOACs compared with aspirin. DOACs were associated with a reduced length of stay, and DOACs did not increase the risk of further surgery, wound problems, bleeding complications, or mortality compared with aspirin

In total knee arthroplasty (TKA), both intravenous (IV) and/or intra-articular (IA) administration of tranexamic acid (TXA) were showed to reduce blood loss. Moreover, research suggesting TXA decreases postoperative knee swelling, but it is unknown whether this results in improved postoperative rehabilitation outcome. Thus, the aim of this study was to evaluate whether combined IV and IA administration of TXA would associate with improved early rehabilitation outcomes. In this institutional review board approved randomized controlled trial, 179 patients scheduled for unilateral TKA were randomized to one of three regimens: (1) IA administration of 1gm TXA at end of procedure only, (2) additional preoperative IV dose of 15 mg/kg 30min before tourniquet inflation, and (3) additional postoperative dose 4hrs after preoperative dose. Primary outcomes included knee range of motion, Knee Society Score (KSS) at 6-month postoperatively, haemoglobin drop at day-2 post-operatively, and transfusion rate. Secondary outcome was venous thromboembolism (VTE) complications. Baseline characteristics were comparable between the allocation groups. Patients in regimen (3) showed statistically significant better knee extension range (6.2°, 5.9°, 2.9°, p=0.01), and KSS (88.5, 89.9, 93.0, p=0.02) at 6-month postoperatively, and lesser drop in haemoglobin at day-2 post-operatively (2.72, 2.47, 1.75 g/dL, p=0) when compared with patients in other regimens. No patients required transfusion, or complicated by VTE. The combined administration of IA and IV TXA, including both preoperative and postoperative doses, associated with statistically significantly improved early rehabilitation outcomes. The improvement may be related to higher haemoglobin level and decreased knee swelling in patients having regimen (3). For any reader queries, please contact . cpk464@yahoo.com.hk

Introduction. We studied the safety and efficacy of multimodal thromboprophylaxis (MMP) in patients with a history of venous thromboembolism (VTE) undergoing total hip arthroplasty (THA). MMP includes discontinuation of procoagulant medications, VTE risk stratification, regional anesthesia, an intravenous bolus of unfractionated heparin before femoral work, rapid mobilization, the use of pneumatic compression devices, and chemoprophylaxis tailored to the patient's risk. Material and methods. From 2004 to 2018, 257 patients (mean age: 67 years; range: 26–95) with a history of VTE underwent 277 primary, elective THAs procedures (128 right, 100 left, 9 single-stage bilateral, 20 staged bilateral) by two orthopaedic surgeons at a single institution. The patients had a history deep vein thrombosis (DVT) 186 (67%), pulmonary embolism (PE) 43 (15.5%), or both 48 (17.5%). Chemoprophylaxis included aspirin (38 patients) and anticoagulation (239 patients; Coumadin: 182, low-molecular-weight heparin: 3, clopidogrel: 1, rivaroxaban: 3, and a combination: 50). Forty eight patients (17.3%) had a vena cava filter at the time of surgery. Patients were followed for 120 days to detect complications, and for a year to detect mortality. Results. Postoperative VTE was diagnosed in seven patients (2.5%): DVT in five, and PE with and without DVT in one patient each. Bleeding complications occurred in 2 patients, one requiring surgical evacuation of a hematoma. Seven patients died during the first year (2.5%). One patient died 5 months postoperatively of a fatal PE during open thrombectomy, and one patient died of a hemorrhagic stroke while receiving Coumadin. PE or bleeding was not suspected in any of the remaining 5 fatalities. Conclusions. The result of this study spanning over 13 years, suggests that MMP is safe and effective. Postoperative anticoagulation should be prudent as very few patients developed postoperative VTE (2.5%) or died of suspected or confirmed PE. Mortality during the first year was mostly unrelated to VTE or bleeding. For any tables or figures, please contact the authors directly

Venous thromboembolism (VTE) is the second most common complication and pulmonary embolism (PE) is the fourth most common cause of death after a hip fracture. Despite thromboprophylaxis, deep vein thrombosis (DVT) is detected in up to 45% of hip fracture patients. Thrombelastography (TEG) is a whole-blood, point of care test capable of providing clinicians with a global assessment of the clotting process, from fibrin formation to clot lysis. Maximal amplitude (mA) from TEG analysis is a measure of clot strength. Elevated admission mA values of >65mm and >72mm have been determined to be independent predictors of in-hospital PE. The coagulation index (CI) is calculated based on TEG parameters and defines hypercoagulable state as CI >3. This study aimed to use serial TEG analysis to determine the duration of hypercoagulable state after hip fracture. A prospective cohort of hip fracture patients >50 years of age amenable to surgical treatment (AO 31A1–A3 & 31B1–B3) were enrolled at a Level I trauma centre. Serial TEG analysis (TEG 6S) was performed every 24-hours from admission until 5-days post-operatively and at 2- and 6-week follow-up visits. All patients received a minimum of 28 days of thromboprophylaxis. Descriptive statistics and single sample t-tests were used for comparison of mA to the 65mm threshold. Thirty-five patients (26 female) with a median age of 83 (range = 71–86) years were included. On admission, 31.4% and 82.9% of patients were hypercoagulable based on mA >65mm and CI, respectively. At 2 weeks, all patients remained hypercoagulable, however, mA >72mm showed that 16 patients (47.1%) were at even higher risk for VTE. At 6-weeks, 65.7% and 97.1% of patients were hypercoagulable based on mA >65mm and CI, respectively. When compared with the mA >65mm threshold, patients were hypocoagulable at the time of admission (mA = 62.2 (±6.3), p = 0.011), but became significantly more hypercoagulable at 2-weeks (mA = 71.6 (±2.6), p < 0 .001), followed by continued hypercoagulability at 6-weeks, however not significantly elevated above the 65mm threshold (mA = 66.2 (±3.8), p = 0.058). One patient developed a symptomatic DVT at 2-weeks and had a mA = 72.9 and a CI of 5.9. This is the first study to demonstrate that >50% of hip fracture patients remain hypercoagulable 6 weeks post fracture despite thromboprophylaxis, and there are individual hypercoagulable responses. This is critical, as guidelines only recommend 28 to 35 days of thromboprophylaxis in this high-risk population. Previously determined mA thresholds may be a more sensitive test for risk-stratifying patients' VTE risk than the CI threshold. Additionally, assessing ΔmA using serial TEG may better predict VTE risk

Aims. To evaluate the incidence of primary venous thromboembolism (VTE), epidural haematoma, surgical site infection (SSI), and 90-day mortality after elective spinal surgery, and the effect of two protocols for prophylaxis. Patients and Methods. A total of 2181 adults underwent 2366 elective spinal procedures between January 2007 and January 2012. All patients wore anti-embolic stockings, mobilised early and were kept adequately hydrated. In addition, 29% (689) of these were given low molecular weight heparin (LMWH) while in hospital. SSI surveillance was undertaken using the Centers for Disease Control and Prevention criteria. Results. In patients who only received mechanical prophylaxis, the incidence of VTE was 0.59% and that of SSI 2.1%. In patients who were additionally given LMWH, the incidence of VTE was 0% and that of SSI 0.7%. The unadjusted p-value was 0.04 for VTE and 0.01 for SSI. There were no cases of epidural haematoma or 90-day mortality in either group. When adjusted for case-mix, LMWH remained a significant factor (p = 0.006) for VTE, but not for SSI. Conclusion. A peri-operative protocol involving mechanical anti-embolism stockings, adequate hydration, and early post-operative mobilisation is effective in significantly reducing the incidence of VTE. The addition of LMWH is safe in patients at higher risk of developing VTE. Cite this article: Bone Joint J 2017;99-B:1204–9

Venous thromboembolism (VTE) prophylaxis following total joint arthroplasty (TJA) should be individualised in order to maximise the efficacy of prophylactic measures while avoiding the adverse events associated with the use of anticoagulants. At our institution, we have developed a scoring model using the Nationwide Inpatient Sample (NIS) database, which is validated against our institutional data, to stratify patients into low- and high-risk groups for VTE. Low-risk patients are placed on aspirin 81 mg twice daily for four weeks post-operatively, and high-risk patients are placed on either a Vitamin K antagonist (warfarin), low molecular weight heparin, or other oral anticoagulants for four weeks post-operatively. All patients receive sequential pneumatic compression devices post-operatively, and patients are mobilised with physical therapy on the day of surgery. Patients who have a history of peptic ulcer disease or allergy to aspirin are also considered for other types of anticoagulation following surgery. Risk Stratification Criteria. Major comorbid risk factors utilised in our risk stratification model include history of hypercoagulability or previous VTE, active cancer or history of non-cutaneous malignancy, history of stroke, and pulmonary hypertension. We consider patients with any of these risk factors at elevated risk of VTE and therefore candidates for formal anticoagulation. Other minor risk factors include older age, bilateral surgery compared with unilateral, inflammatory bowel disease, varicose veins, obstructive sleep apnea, and history of myocardial infarction, myeloproliferative disorders, and congestive heart failure. Each minor criterion is associated with a score. The cumulative score is compared with a defined threshold and the score that surpasses the threshold indicates that the patient should receive post-operative anticoagulation. To facilitate the use of this scoring system, an iOS mobile application (VTEstimator) has been developed and can be downloaded from the app store

Introduction. Venous thromboembolism (VTE), including pulmonary embolism (PE) resulting from deep vein thrombosis (DVT), remains a well-known serious complication after femoral fractures. The low molecular heparin is widely used to prevent VTE. This study compared the effectiveness of VTE prevention between dalteparin and enoxaparin. Materials and Methods. From 2013 to 2014, we retrospectively recruited 712 patients who had femoral fractures with operative treatment. All patients receiving VTE chemoprophylaxis with perioperative period using dalateparin in Group 1(N=395) and enoxaparin in Group 2(N=317). The prophylactic dosing was determined using individual product labeling and identified as enoxaparin 40 mg every 12 hours and dalteparin 2500 international unit (IU) once daily, based on clinical practice guidelines. The prophylaxis was started at admission, and maintained during average 8.43.5 days after operation. The outcome including the incidence of clinically significant deep vein thrombosis, pulmonary embolism, perioperative bleeding and cost of drugs were evaluated between two groups. Results. The two study groups did not differ significantly in fracture type, age, gender, ASA score. The overall incidence of VTE is similar between two groups. However, the incidence of fatal PE is significantly lower in patients with dalteparin (Group 1: 4/395(1.00%), Group 2: 10/317(3.15%), p<0.001). And the overall cost of each group is significantly different between two groups (Group 1: average KRW 89,426, Group 2: average KRW 32,188, p<0.001). Conclusion. Both dalteparin and enoxaparin could be safely used without notable complications in VTE prophylaxis. However, dalteparin had more advantages for prevention of fatal PE, compared to enoxaparin in patients with femoral fractures with significant cost effectiveness

Background. This retrospective analysis was prompted by the authors' observation of the relatively high incidence of venous thromboembolism (VTE) in the surgical repair of acute Achilles tendon ruptures. Method. 88 patients were treated surgically for an acute Achilles tendon rupture. No prophylactic anticoagulation was given to any patients. The incidence of VTE was then reviewed retrospectively. Results. Five patients developed symptomatic deep vein thrombosis (5.7%) and one a near-fatal pulmonary embolus (1.1%). There were no major bleeding or cardiovascular adverse events. One patient developed a thrombus of the the lesser saphenous vein (1.1%) and there was one superficial sepsis (1.1%). A temporary peroneal nerve palsy occurred in one patient (1.1%). There were two re-ruptures (2.3%). Conclusion. There is no doubt that thromboprophylaxis must be given to the high risk patient and is also recommended for major orthopaedic surgery. Limited data is available for the use of thromboprophylaxis in foot and ankle surgery. In light of the unacceptably high incidence of venous thromboembolism in this study, the authors suggest that routine venous thromboembolism prophylaxis should be considered for these patients. MULTIPLE DISCLOSURES

The aim of this study was to define the incidence of venous thromboembolism (VTE) and risk factors for the development of deep-vein thrombosis (DVT) after the resection of a musculoskeletal tumour. A total of 94 patients who underwent resection of a musculoskeletal tumour between January 2003 and December 2005 were prospectively studied. There were 42 men and 52 women with a mean age of 54.4 years (18 to 86). All patients wore intermittent pneumatic compression devices and graduated compression stockings. Ultrasound examination of the lower limbs was conducted to screen for DVT between the fifth and ninth post-operative days. DVT was detected in 21 patients (22%). Of these, two were symptomatic (2%). One patient (1%) had a fatal pulmonary embolism. Patients aged ≥ 70 years had an increased risk of DVT (p = 0.004). The overall incidence of DVT (both symptomatic and asymptomatic) after resection of a musculoskeletal tumour with mechanical prophylaxis was high. It seems that both mechanical and anticoagulant prophylaxis is needed to prevent VTE in patients who have undergone the resection of a musculoskeletal tumour. Cite this article: Bone Joint J 2013;95-B:1280–4

British national guidelines recommend agents which antagonise factor Xa or warfarin as prophylaxis of venous thromboembolism (VTE) in lower limb arthroplasty. However, they discourage the use of aspirin prophylaxis. We conducted a prospective, multi-centre audit between two national centres, Ninewells Hospital in Dundee and the Royal Infirmary in Edinburgh to compare bleeding and VTE risk. Only Edinburgh routinely uses aspirin as VTE prophylaxis. The study comprises a number of cycles from 2013 to 2015. Consecutive groups of patients were identified prospectively using elective theatre data and information extracted from their case-notes on type of VTE prophylaxis, VTE occurrence, wound complications and length of hospital stay for a period of nine weeks post-operatively. 262 Edinburgh patients and 92 Dundee patients were included. Most Edinburgh patients were prescribed aspirin in hospital and on discharge (188/262, 71.8%), in line with local protocol. In Dundee, dalteparin was most commonly prescribed in hospital (68/92, 73.9%) and rivaroxaban on discharge (57/92, 62.0%). The Edinburgh group had a 1.5% incidence of pulmonary embolus (PE) and a 1% rate of deep venous thrombosis (DVT), 2% had problems with wound haematoma and one patient (0.4%) required a transfusion; no wound washouts were required. In Dundee there was 0% PE, 2% DVT, 5% had problems with haematoma, 3% required transfusion and 2% required washout. There was no difference in length of hospital stay, with a mode of 4 days for both centres. Non-fatal PE was prevented in Dundee patients but possibly at the cost of greater incidence of wound complications

It is important to be able to identify patients with an increased risk of venous thromboembolism (VTE) in order to minimise the risk of an event. We investigated the incidence and risk factors for post-operative VTE in 168 consecutive patients with a malignancy of the lower limb. The period of study included ten months before and 12 months after the introduction of chemical thromboprophylaxis. All data about the potential risk factors were identified and classified into three groups (patient-, surgery- and tumour-related). The outcome measure was a thromboembolic event within 90 days of surgery. Of the 168 patients, eight (4.8%) had a confirmed symptomatic deep-vein thrombosis and one (0.6%) a fatal pulmonary embolism. Of the 28 variables tested, age > 60 years, higher American Society of Anesthesiologists grade and metastatic tumour were independent risk factors for VTE. The overall rate of symptomatic VTE was not significantly different between patients who received chemical thromboprophylaxis and those who did not. Knowledge of these risk factors may be of value in improving the surgical outcome of patients with a malignancy of the lower limb. Cite this article: Bone Joint J 2013;95-B:558–62

Aims: To evaluate the inßuence of the type of anesthesia on the superior efþcacy of fondaparinux over enoxaparin in preventing venous thromboembolism (VTE) in orthopedic surgery (RRR > 50%; P< 0.0001). Methods: 4 randomized, double-blind trials were performed: 2 in hip replacement (THR), 1 in North America (NA) and 1 in Europe; 1 in knee surgery (MKS); and 1 in hip-fracture surgery (HF). The choice of anesthesia was left to the investigators. A predeþned covariate analysis according to the type of anesthesia was performed on primary efþcacy. Conclusions: Fondaparinux once-daily started postoperatively provided superior efþcacy versus enoxaparin in preventing VTE whatever the type of anesthesia and may improve convenience in current practice

Purpose. The hip fracture has been increasing as the aging population continues to grow. Hip fracture patients are more susceptible to blood loss and venous thromboembolism (VTE). The objective of this study was to assess the efficacy and safety of tranexamic acid (TXA) in fracture patients undergoing fast-track hemiarthroplasty. Methods. 609 hip fracture patients undergoing hemiarthropalsty from January 2013 to September 2016 were prospectively selected. 289 patients received 15 mg/kg TXA prior to surgery, and the remaining 320 patients received no TXA. All the patients received a fast-track program including nutrition management, blood management, pain management, VTE prophylaxis and early mobilization and early intake. The primary outcome was transfusion requirement, other parameters such as blood loss, hemoglobin (Hb) level, VTE, adverse events and length of hospital stay were also compared. Multivariate logistic regression analysis and meta-analysis were also performed to identify the risk factors of transfusion and confirm the results of current study. Results. Transfusion of at least 1U of erythrocyte blood cell occurred in 25 patients (8.65%) in treatment group and in 77 (24.06%, OR=0.299, p<0.001) in control group. The mean level of Hb on POD 1 (111.70±18.40 g/L) and POD 3 (108.16±17.25 g/L) in TXA group were higher than control group (107.29±18.70 g/L, p= 0.008; 104.22±15.16 g/L, p= 0.005 respectively). More patients get off bed to ambulate within 24 hours after surgery in TXA group (37.02% Vs 26.25%, p= 0.004). And the length of hospital stay was shorter (11.82±4.39 Vs 15.96±7.30, p= 0.003). No statistical significance were detected regarding VTE and other adverse events. Logistic regression analysis showed that the relative odds reduction after adjustment for these covariates was 67% (OR= 0.327, 95%CIs= 0.197 to 0.544) in favor of tranexamic acid. Other risk factors included preoperative hemoglobin level, operation time, VTE prophylaxis. Pooling the data showed that tranexamic acid led to a significant reduction in transfusion (OR= 0.33, 95%CIs= 0.25 to 0.43) without sacrificing safety (OR= 0.70, 95%CIs= 0.25 to 1.97). Conclusion. Tranexamic acid was effective and safe to reduce blood loss and transfusion in geriatric hip fracture patients undergoing fast-track hemiarthroplasty

Since the establishment of our department a multi-modal approach to thromboprophylaxis that uses aspirin for chemical prophylaxis was adopted. In accordance with the latest national recommendations, our routine chemical prophylaxis following arthroplasty was changed to rivaroxaban in 2012 and then dalteparin in 2013. This study aimed to compare venous thromboembolism (VTE) rates during the use of the aspirin-based protocol used from 2004 to 2011 with recent, rivaroxaban and dalteparin-based guidelines. Outcome data from ISD Scotland was retrieved and radiology reports performed for CT pulmonary angiograms and lower limb doppler ultrasound scans in our institution were assessed to identify cases of VTE following primary hip or knee arthroplasty. The incidence of pulmonary embolism (PE) and proximal deep venous thrombosis (DVT) was calculated for each year and compared using a Chi-squared test. Additionally, the change in extended thromboprophylaxis regimen was surveyed by recording the discharge prescriptions for consecutive arthroplasty patients for March every year. There were 90 radiologically confirmed cases of DVT or PE between 2004 and 2011 (incidence of 0.71%). The DVT/PE rate was subsequently 0.67% in 2012 and 0.69% in 2013, with a further 29 cases identified. This does not represent a significant change in the venous thromboembolism rates and remains below the national incidence of VTE (1.06%). Aspirin alone was used as chemical thromboprophylaxis in 80.8% of patients from 2004 to 2011, 50.9% in 2012, and 12.1% in 2013. The incidence of VTE at our centre remains favourable to national figures, but the modification of thromboprophylaxis guidelines will incur additional financial costs and has not had a significant reduction on the rate of VTE