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. 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

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. 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

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

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

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

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