Introduction. VTE is a possible complication of foot and ankle surgery, however there is an absence of agreement on contributing risk factors in the development of VTE. The primary outcome of this study was to analyse the 90-day incidence of symptomatic VTE following foot and ankle surgery and to determine which factors may increase the risk of VTE. Methods. This was a national, multi-centre prospective audit spanning a collection duration of 9 months (2022/2023). Primary outcomes included incidence of symptomatic VTE and VTE related mortality up to 90 days following foot and ankle surgery and Achilles tendon rupture, and analysis of risk factors. Results. In total 11,363 patients were available for analysis. 5,090 patients (44.79%) were elective procedures, 4,791 patients (42.16%) were trauma procedures (excluding Achilles ruptures), 398 patients (3.50%) were acute diabetic procedures, 277 patients (2.44%) were Achilles ruptures undergoing surgery and 807 patients (7.10%) were Achilles ruptures treated non-operatively. There were 99 cases of VTE within 90 days of admission across the whole group (Total incidence = 0.87%), with 3 cases of VTE related mortality (0.03%). On univariate analysis, increased age and ASA grade showedhigher odds of 90-day VTE, as did previous cancer, stroke, history of VTE, and type of foot and ankle procedure / injury (p<0.05). However, on multivariate analysis, the only independent predictors for 90-day VTE were found to be the type of foot and ankle procedure (Achilles tendon rupture = Odd's Ratio 11.62, operative to 14.41, non-operative) and ASA grade (grade III/IV = Odd's Ratio 3.64). Conclusion. The incidence of 90-day post procedure VTE in foot and ankle surgery in this national audit was low. Significant, independent risk factors associated with the development of 90-day symptomatic VTE were Achilles tendon rupture management and high ASA grade

Major orthopaedic surgeries such as total hip and total knee replacements are considered a major risk factor for venous thromboembolism (VTE). Without prophylaxis, DVT occurs in 10–40% of general surgical or medical patients and 40–60% of patients following major orthopaedic surgery. There has, however, been a perception that VTE is less common in Asia than in Western countries. New evidence has emerged recently that contradicts this perception. Results from multinational epidemiological studies (SMART, AIDA, ENDORSE) clearly showed that the rate of venographic and symptomatic thrombosis after major joint replacement in Asian patients is similar to that previously reported in patients in Western countries. However, thromboprophylaxis is not routinely used in Asia, even in situations considered high risk in Western countries. The ENDORSE study reported that less than 20% of at-risk surgical patients in Asia received prophylaxis compared with over 80% in Western countries. This leaves the majority of patients at risk of developing VTE and VTE-related conditions, which continues after hospital discharge. Current guidelines recommend the use of thromboprophylaxis for at least 10 days and up to 35 days in patients undergoing total joint replacement. Available anticoagulants are effective at preventing VTE but are associated with various limitations, such as parenteral administration as in the case of UFH and LMWH. A narrow therapeutic window, unpredictable pharmacology, frequent coagulation monitoring and dose-adjustment as in the case of vitamin K antagonists (VKAs). Several new, oral anticoagulants are in advanced clinical development, including the direct thrombin inhibitor, dabigatran, and the direct Factor Xa inhibitors, rivaroxaban and apixaban

Rivaroxaban, an oral, direct FXa inhibitor has shown in large phase III trials to be both superior to enoxaparin a low molecular weight heparin for VTE prophylaxis in patients undergoing MOS, and to also have a good safety profile. RECORD, a pivotal clinical trial program investigating rivaroxaban for the prevention of VTE after THR and TKR surgery, consists of four multinational, randomized, double-blind, double-dummy phase III studies (RECORD1,2,3 and 4) comparing rivaroxaban 10 mg once-daily with enoxaparin 40 mg once-daily or 30 mg twice-daily. The RECORD program has consistently shown superiority of rivaroxaban to enoxaparin at preventing VTE after major orthopaedic surgery. Results from the RECORD 2 study confirmed the benefit of extended thromboprophylaxis after THR. Rivaroxaban was more effective than enoxaparin at reducing the incidence of VTE and all course mortality in patients undergoing THR, with a relative risk reduction (RRR) of 70% in total VTE (RECORD 1). In the TKR populations, rivaroxaban was superior to both once-daily (RECORD 3) and twice-daily (RECORD 4) enoxaparin, with a RRR of 49% and 31.4%, respectively. It also significantly reduced the incidence of symptomatic VTE in TKR patients (RECORD 3). Rivaroxaban groups had low and similar bleeding rates to enoxaparin across the RECORD program. Thus, with its superior efficacy and a good safety profile, oral, once-daily fixed dosing with rivaroxaban could transform the future of VTE prevention after major orthopaedic surgery and improve the quality and reliability of patients care

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

Trauma patients have the highest risk of VTE among hospitalised patients1, with a reported 13-fold increase of risk2. Due to the heterogeneity of injuries, the true incidence of VTE in trauma patients is difficult to obtain. This study examines the incidence of VTE and associated complications in trauma patients with lower limb injuries. Between 2005 and 2009, patients over 18 years of age with lower limb injuries and/or fractures that were either isolated or a part of multi-systemic injuries were included in the study. Further stratification was performed according to the Injury Severity Score: an ISS greater than 15 was a major (trauma); less than 15, a minor. The mode of VTE prophylaxis, type of surgery, and bleeding complications were also examined. There were 5528 patients in the minor trauma group, and 509 in the major trauma group. Minor trauma: the mean age was 58.1 years (range: 18 – 104). The VTE incidence was 1.2%: 0.67% for DVT, and 0.5% for PE. The readmission rate within a three-month period was 11%, of which 2.8% were due to VTE with 13 cases of DVT, and 5 cases of PE. The 30-day mortality rate was 2.2%. Seven patients died from PE during admission, while one died from PE within three months after discharge. Major trauma: the mean age was 42.5 years (range: 18 – 95). The overall VTE incidence was 7.8%: 5.9% for DVT, and 0.9% for PE. The readmission rate within a three-month period was 7.6%, of which 5% were due to VTE with 2 cases of DVT. The overall 30-day mortality rate was 11.1%, and there was no formally-diagnosed fatal PE during admission or post-discharge. Major trauma patients had a 7-fold increased risk of developing VTE during admission when compared to minor trauma patients, although minor trauma patients had more fatal PEs. Additionally, major trauma patients had a 10-fold increased risk for DVT, and a 3-fold risk for PE, when compared with minor trauma patients. No significant difference was detected between the two groups for the 30-day readmission rate due to VTE

Nice guidelines recommend VTE prophylaxis to patients in below knee casts following foot and ankle surgery following risk assessment. The guidelines are controversial and BOFAS recommendations reiterate the risk factors but highlight poor evidence to support these guidelines. Implementation has been variable dependent on interpretation. 58 patients who underwent hindfoot procedures and were immobilised in a cast were identified. These patients were under the care of two consultants, one of whom anticoagulates with daily enoxaparin and one who does not, providing a de facto case-control design. The patients were followed up to identify those who subsequently suffered a DVT or PE, and the clinical circumstances. 2 cases of VTE events were noted in 58 patients undergoing foot and ankle surgery. Both were elective cases managed postoperatively in cast and treated with prophylaxic enoxaparin. Both of these presented to hospital with signs of VTE greater than 6 weeks following surgery after cast removal and discontinuation of enoxaparin. No patients were considered high risk according to NICE guidelines. None of the patients who received no thromboprophylaxis had a clinical DVT. Within our study group we found that VTE thromboprophylaxis does not influence clinically evident VTE rates. Patients who developed VTE were not considered high risk by definition of NICE guidelines but only at increased risk due to their immobility. The VTE events were initiated while the patients were receiving thromboprophylaxis. The effectiveness of the guidelines in predicting patients who would benefit from chemoprophylaxis is questionable from this study. NICE guidelines on VTE thromboprophylaxis have been received with some concerns. Although this investigation studied only a relatively small number of patients, it raises issues about the clinical effectiveness of the guidelines in foot and ankle patients

Venous Thromboembolism (VTE) prophylaxis is an essential part of orthopaedic surgeries in preventing life-threatening thromboembolic events such as Deep Vein Thrombosis (DVT) and Pulmonary Embolism (PE). Orthopaedic surgery has the highest incidence rate of thromboembolic events as compared to any other surgical specialities, making it an essential component in managing any orthopaedic case. At Queen's Medical Centre (QMC), a major trauma centre in the United Kingdom (UK), sees up to 750 NOF fracture cases annually, making it one of the busiest trauma and orthopaedic centres in the UK. Our study aims to evaluate how VTE Prophylaxis is conducted in a UK Major Trauma Centre for NOF and pelvic fragility fractures and how human factors can improve its efficacy. The Nottingham University Hospitals (NUH) Trust has implemented new guidelines from August 2019 that patients with fragility fractures such as NOF and pelvic fractures are prescribed with 28 days VTE prophylaxis with Enoxaparin, or their own anti-coagulants if risk of thrombosis exceed the risk of bleeding. This is an adaptation from the trust to align their guidelines closer to the NICE 2018 guidelines. We will be evaluating the initial compliance of VTE Prophylaxis, identify and utilise human factors, then re-analyse the department after implementing interventions on the same batch of junior doctors working in the department. Data of 100 patients with fragility fractures were collected, 50 consecutive patients in the pre-intervention window during August 2019 and 50 in the post-intervention window during November 2019. The pre-intervention data had 43 NOF and 7 Pelvic fractures. Our study showed that 93% of NOF fracture and 100% of pelvic fracture received the correct course of VTE prophylaxis. The data was presented at the local department junior doctor academic session. Three simple human factor interventions were implemented over the course of September and October: Education to the trauma and orthopaedic department on the new guideline, extended VTE labels on drug charts for patients with fragility fractures, VTE reminder labels at doctors' stations. Another 50 consecutive patients' data were collected during November 2019. Data shows that 97.8% of NOF (p>0.05) and 60% of pelvic fracture (p>0.05) received the correct course of VTE prophylaxis. Our data has shown an increase in correct VTE prescription for NOF fracture patients, which is the main bulk of our fragility fracture patients whilst we see a drop in pelvic fracture patients. Due to the limited time frame of four months where junior doctors in the UK rotate between specialities, we are only able to collect data during the first month, implement interventions between datasets and collect data on the final month of the four-month rotation. A future bigger study might provide a more significant result on the department. We believe that the key to achieving 100% VTE prophylaxis in the T&O department is optimising human factors, educating junior doctors, who are not orthopaedic trained, with sufficient information of the guidelines, and evidence of the risk and benefits of providing prolonged VTE prophylaxis for orthopaedic patients. In conclusion, we found that QMC, a major trauma centre with high patient volume and turnover, has a high level of compliance with VTE prophylaxis for fragility fractures and it is imperative that utilising human factors will inch the department closer to its goal of 100% VTE compliance

Introduction. Guidelines from the North American Spine Society (2009 and 2013) are the best evidence-based instructions on venous thromboembolism (VTE) and antibiotic prophylaxis in spinal surgery. NICE guidelines exist for VTE prophylaxis but do not specifically address spinal surgery. In addition, the ruling of the UK Supreme Court in 2015 resulted in new guidance on consent being published by the Royal College of Surgeons of England (RCSEng). This study assesses our compliance in antibiotic, VTE prophylaxis and consent in spinal surgery against both US and UK standards. Methods. Retrospective review of spinal operations performed between August and December 2016. Case notes, consent forms and operation notes were analysed for consent, peri-operative antibiotic prescribing and post-operative VTE instructions. Results. Four Spinal surgeons performed 45 operations during this period. 31 patients (69%) received a copy of the signed consent with this process being formally documented in 22 (71%) of those cases. All patients were consented by a competent surgeon. 82% of cases consented prior to the date of procedure were countersigned on the day of operation. There was a mean time of 25.3 days between initial consent and operation (Range: 0–170). 37 (82%) cases had clear instructions for VTE and antibiotic prophylaxis. All prescribed post-operative antibiotics were administered. Discussion. The North American Guidelines state that prophylactic antibiotic is appropriate in all spinal surgery with prolonged cases requiring intraoperative re-dosing and only complex cases needing a postoperative regimen. Eight patients underwent a complex procedure and 7 appropriately received postoperative antibiotics. Of the 29 patients that underwent a simple procedure, 12 did not receive post-operative regimen, in line with the guidelines. However, the remainder 17 were over treated. The US Guidelines recommend mechanical VTE prophylaxis only in elective spinal surgery except in high risk patients. All our patients received VTE mechanical prophylaxis. RCSEng guidelines require consent being taken prior to procedure by a competent surgeon and confirmed on day of procedure. All patients in our cohort were consented prior to the date of operation allowing time for considering options and independent research. 82% of patients had consent confirmed on day of operation. Conclusion. This study demonstrates that we met guideline advice for all patients with regards VTE prophylaxis. We have a tendency to over treat with post-operative antibiotics and not all patients had their consent confirmed on day of procedure but was consented well before day of operation. North America still lead the way with guidelines on spinal surgery to which we should adhere, with NICE guidelines providing limited instructions. New consenting guidelines from RCSEng may not be currently widely known and thus should be a source of education for all surgeons

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

NICE guidelines state that patients undergoing hip or knee arthroplasty should start as an in-patient and then continue pharmacological VTE prophylaxis for 28–35 days. Retrospective review of all elective hip and knee arthroplasties during one calendar month gave a baseline measurement of how many patients had VTE prophylaxis prescribed on their discharge summary. A new, electronically completed, bespoke Trauma and Orthopaedic discharge summary was created with a discreet area clearly marked for VTE prophylaxis, to serve as a reminder to prescribe it. In March 2012, 93 patients underwent hip/knee arthroplasty. 76% (71/93) were prescribed VTE prophylaxis to take home, there was no clinical reason explaining the failure to prescribe prophylaxis in the remaining 24%. In July 2013, after implementation of the change, 117 patients underwent hip/knee arthroplasty. 99% (116/117) were prescribed VTE prophylaxis to take home. Repeat audit in October 2013 showed that 103 patients underwent hip/knee arthroplasty and 100% were prescribed VTE prophylaxis. A simple but clear change to paperwork, brought about a rapid and seemingly lasting change in the prescription of out-patient VTE prophylaxis. The improvement was seen before and after a change of the Junior Doctor workforce suggesting the change in documentation was the main influencing factor

We report decreased clinical VTE rates following increased use of mechanical prophylaxis in elective kip and knee arthroplasty. Usage of intermittent pneumatic compression (IPC) increased due to the increased availability of pump machinery. Timing of IPC use also changed with IPC used intraoperatively on the unoperated limb and for a longer period postoperatively Clinical VTE rates are assessed for two years prior to the change in practice (1140 procedures) and two years afterwards (1285 procedures). There was no other change in practice (chemical thromboprophylaxis, anesthetic technique, use of compression stockings, usage of tourniquet or usage of cement) or in patient profile. Overall clinical VTE rates during admission dropped from 2.98% to 0.62% (p<0.0001). This decrease was seen in both hips 1.77% to 0.2% (p=0.029) and knees 3.97% to 0.89% (p=0.0002). There was a decrease in both pulmonary emboli 1.14% to 0.16% (p=0.0043) and symptomatic DVT 1.84% TO 0.47% (p=0.0023). There was no change in the rate of post discharge VTE events recorded 1.07% (p=0.57), either for DVT or PE (P=0.74 for each). We conclude that IPC with non-sequential calf compression is effective in reducing the rates of clinical in-hospital VTE after elective hip and knee arthroplasty

Background. Despite the suggestion by Virchow in 1856 that thrombosis was the result of venous stasis, endothelial dysfunction and hypercoagulability there are some fundamental questions which remain to be answered. The published studies fail to provide specific details such as cast type and anatomical location of the thrombosis, but instead focus on the incidence of VTE and which chemical thromboprophylaxis is most effective. Previous studies of VTE in trauma patients have involved small numbers of patients and have not look at the risk medium to long term risk. Most importantly they have not looked at the site of the VTE. This makes interpretation of the link between cast and VTE even more complex. Methodology. We analysed 1479 consecutive trauma cast applications and the incidence of symptomatic VTE in the six months following the injury. The diagonosis, cast type and site of the VTE was recorded. Results. The overall incidence of DVT was 2.5% (2.2% distal and 0.3% proximal), 50% occured inthe first 3 weeks, the rest were between 6–13 weeks. The incidence of PE was 0.7%, there was 1 death due to PE. Achilles tendon injury was a statistically significant risk factor, there were no other conditions with a specific risk. There was no difference between above and below knee cast immobilisation. However all symptomatic DVTs occured in the casted leg. Discussion. This is the first study to look at long term VTE risk and the site of thrombosis, these findings have implications for VTE prophylaxis. It would appear that the risk of developing symptomatic VTE extends beyound the currently advised treatment period. It also suggests that venous stasis and endothelial damage are more important that hypercoagulability in the development of VTE after cast treatment for trauma. We recommend a programme of exercises within the cast to reduce this risk

Purpose: A retrospective database analysis was conducted to. determine the extent to which the American College of Chest Physicians (ACCP) guidelines for VTE prophylaxis are followed after total hip replacement (THR) and total knee replacement (TKR) and. evaluate the incidence of VTE for patients receiving and not receiving prophylaxis according to ACCP guidelines (‘ACCP’ and ‘non-ACCP’, respectively). Method: A claims database associated with a large US health plan was linked to the Premier database, which provides details of in-patient medication use. Patients ≥18 years undergoing TKR/THR and enrolled in the health plan 90 days before and 90 days following discharge from hospitalization (or until death) were included. Patients were considered to have received ACCP-guideline prophylaxis if they:. received LMWH, fondaparinux, or VKA following surgery. initiated prophylaxis within one day of surgery (for THR patients) and. were prescribed prophylaxis for a minimum of ten days, or until the occurrence of major bleeding, VTE, or death. In addition, the number of DVTs and PEs occurring in ACCP and non-ACCP patients was recorded. Results: Of the 30,644 eligible patients from the health plan, 3,497 patients were linked to the in-patient database. Except for geographic indicators, there were no significant differences in demographics or baseline co-morbidities between those included and excluded from the final study sample. Of the 3,497 linked patients, 1,395 (40%) received ACCP prophylaxis. The number of DVTs occurring in the ACCP and non-ACCP groups were 28 (2.01%) and 79 (3.76%), suggesting that non-ACCP patients were almost twice as likely as ACCP patients to have a DVT (p=0.0521). The number of PEs occurring in the ACCP and non-ACCP groups were 2 (0.14%) and 25 (1.19%), respectively, suggesting that non-ACCP patients were 8.5 times more likely than ACCP patients to experience a PE (p< 0.0001). Conclusion: This study offers a unique perspective on ‘real-world’ prophylaxis patterns and clinical outcomes in THR/TKR patients. It suggests that 40% of patients received ACCP prophylaxis and that patients not receiving ACCP prophylaxis were almost twice as likely to have a DVT and more than eight times as likely to experience a PE

Financial impact and patient satisfaction with four different anticoagulants for hip and knee arthroplasty in patients with a previous history of VTE- A prospective randomised trial. Introduction. New generation oral anticoagulants (dabigatran/rivaroxaban) have recently become available for the prevention of venous thromboembolism (VTE) following hip and knee arthroplasty. Traditional therapies (warfarin/low molecular weight heparins) are less costly, but have several limitations. The aim of this study was to evaluate the financial impact of substituting enoxaparin and warfarin with newer therapies dabigatran and rivaroxaban. A secondary objective was to investigate patient satisfaction with these treatments. Methods. A randomised prospective study was conducted over a 12 month period. Patients with a history of VTE undergoing hip or knee replacement were randomised to receive one of four anticoagulants for five weeks post surgery. Information was gathered during the hospital stay and then post discharge, by telephone, for five weeks(35 days)to determine costs. The costs included cost of drug, nursing time, blood monitoring and transport costs. The patients were also asked to complete the Duke Anticoagulation Satisfaction Scale (DASS). The DASS is a 26 item questionnaire which has 7 responses for each question. Results. Although dabigatran and rivaroxaban had higher drug acquisition costs, warfarin and enoxaparin were financially more costly overall. These additional costs were mainly due to increased blood monitoring and time for training and administration which is not required for newer therapies. DASS scores were significantly better with dabigatran (38.5±5.1) and rivaroxaban (38.6±8.3) compared to warfarin (71.8±16.2) and enoxaparin (68.5±14.2) (p< 0.001). This indicates more satisfaction for patients prescribed dabigatran or rivaroxaban compared to traditional therapies. Conclusion. The use of new generation oral anticoagulants has the potential to significantly reduce the financial burden of thromboprophylaxis on the NHS with an additional benefit of better patient satisfaction when compared to traditional therapies

Patients with pelvic and acetabular fractures have a high risk of developing thromboembolic complications. Despite routine screening, the risk of PE remains high and may develop in patients with negative DVT screening. The search for a means to identify the patient ‘at risk’ has been elusive.

537 consecutive patients, referred to Royal Adelaide Hospital over a 20 year period for treatment of pelvic and acetabular fractures, were evaluated prospectively for pulmonary embolus (PE). 352 patients referred directly to the author were treated with variable dose heparin as prophylaxis to venous thromboembolic (VTE) disease. 184 patients primarily admitted under the general surgeons or to ITU, prior to referral to the author, were treated with fixed dose heparin or Enoxaparin. All patients were followed prospectively to determine the rate of pulmonary embolus. The heparin dosage requirements of those who developed pulmonary emboli were compared to those who did not. Patients were also identified for whom a clinical diagnosis of deep venous thrombosis (DVT) was made during the study and their heparin dosage requirements were determined.

7 of 352 patients treated with variable dose heparin developed PE (1.98%). 13 of 184 patients treated with fixed dose heparin, Enoxaparin, or combinations, developed PE (7.06%). An incidental finding of DVT was made in 36 patients. Of these, 10 patients (2.8%) were treated with variable dose heparin and 26 patients (14.1%) with fixed dose heparin or Enoxaparin.

The average Injury Severity Score was higher in patients treated with variable dose heparin than those treated with fixed dose regimes. Patients treated with variable dose heparin who developed PE showed a progressively increasing heparin requirement. The majority of patients who did not develop PE (72%) showed a progressively decreasing heparin requirement (suggesting reversal of a prothrombotic state). 21% showed an initial increasing heparin requirement followed by a decreasing requirement (suggesting a prothrombotic state that was reversed, e.g. a DVT successfully treated by the increasing heparin dose provided by a variable dose regime). 4% manifested a static heparin requirement (suggesting maintenance of a prothrombotic state). 8 patients treated with variable dose heparin developed DVT. 6/8 patients manifested a phase of progressively increasing heparin requirement, followed by a decreased requirement, and 2/8 patients manifested a sustained level of heparin requirement.

Patients with pelvic and acetabular fractures treated with variable dose heparin showed a rate of PE (1.98%). This is remarkably low compared with published rates of PE in such patients, and particularly compared with those patients treated only with chemoprophylaxis. The rate of PE was 3.5x higher and the rate of DVT was 5x higher in patients treated with fixed dose heparin or Enoxaparin. Patients who developed PE or DVT manifested an increasing heparin requirement. An increasing dosage of heparin may protect the ‘at risk’ patient from venous thromboembolism. Fixed dose unfractionated heparin/LMWH may be insufficient to treat the ‘at risk’ patient. An increasing heparin requirement may identify the patient ‘at risk’.

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

The aim of this study was to identify factors independently associated with symptomatic venous thromboembolism (VTE) following acute Achilles tendon rupture (ATR), and to suggest a clinical VTE risk assessment tool for patients with ATR. From 2010–2018, 984 consecutive adults (median age 47yrs, 73% male) sustaining an ATR were retrospectively identified. There were 95% managed non-operatively (below-knee cast 52%, n=507/984; walking boot 44%, n=432/984), with 5% (n=45/984) undergoing primary operative repair (<6wks). VTE was diagnosed using medical records and national imaging archives, reviewed at a mean of 5yrs (1–10) post-injury. Regression was performed to identify factors independently associated with VTE. Incidence of VTE within 90 days of ATR was 3.6% (n=35/984; deep vein thrombosis 2.1% [n=21/984], pulmonary embolism 1.9% [n=19/984]). Age ≥50yrs (adjusted OR [aOR] 2.3, p=0.027), personal history of VTE/thrombophilia (aOR 6.1, p=0.009) and family history of VTE (aOR 20.9, p<0.001) were independently associated with VTE. These non-modifiable risk factors were incorporated into a VTE risk assessment tool. 23% of patients developing VTE (n=8/35) had a relevant personal or family history, but incorporating age into the tool identified 69% of patients with VTE (n=24/35). Non weight-bearing ≥2wks after ATR was also independently associated with VTE (aOR 3.2, p=0.026). Age ≥50 years, personal history of VTE/thrombophilia and a positive family history were independently associated with VTE following ATR. Incorporating age into our suggested VTE risk assessment tool enhanced sensitivity in identifying at-risk patients. Early weight-bearing in an appropriate orthosis may be beneficial in VTE risk reduction

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

Background. Venous Thrombo-Embolism is a recognized complication of lower limb immobilization. In the neuropathic patient total contact casting (TCC) is used in the management of acute charcot neuroathropathy and/or to off-load neuropathic ulcers, frequently for long time periods. To our knowledge there is no literature stating the prevalence of VTE in patients undergoing TCC. We perceive that neuropathic patients with active charcot have other risk factors for VTE which would predispose them to this condition and would mandate the use of prophylaxis. We report a retrospective case series assessing the prevalence of VTE in the patients being treated with TCCs. Methods. Patients undergoing TCC between 2006 and 2018 were identified using plaster room records. These patients subsequently had clinical letters and radiological reports assessed for details around the TCC episode, past medical history and any VTE events. Results. There were 143 TCC episodes in 104 patients. Average age at cast application was 55 years. Time in cast averaged 45 days (range 5 days – 8 months, median 35 days). 3 out of 4 patients had neuropathy as a consequence of diabetes. One TCC related VTE (0.7% of casting episodes) was documented. This was a proximal DVT confirmed on USS 9 days following cast removal. No patient received VTE prophylaxis while in TCC. Conclusion. Despite these complex patients having a multitude of co-morbidities the prevalence of VTE in the TCC setting remains similar to that of the general population. This may be due to the fact that TCCs permit weight bearing. This case series suggests that, while all patients should be individually VTE risk assessed as for any lower limb immobilization, chemical thromboprophylaxis is not routinely indicated in the context of TCCs

Introduction. Total contact casting (TCC) is one of the most commonly utilized modalities in the management of diabetic feet. We undertook a retrospective review to determine the prevalence of symptomatic VTE events in patients treated in a weight bearing TCC in our diabetic foot unit, and to formulate guidelines for VTE prophylaxis. Methods. Electronic records were reviewed to identify all patients treated in a TCC between 2014 and 2021. Data collection included patient demographics, comorbidities, period of immobilization in TCC, the incidence of VTE events, and any VTE prophylaxis prescribed during their period in TCC. Results. 549 patients were identified who had at least one episode of TCC. Mean age was 67 years (range 28 to 94 years) and the mean duration in cast was 10.2 weeks (range 0.3–46 weeks). Only 6 patients (1.1%) were prescribed chemical thrombo-prophylaxis during their period in TCC. Mean body mass index (BMI) for these patients was 32.3 (Range 18.4–58.9). Other significant comorbidities: 81% (n-444) of patients had associated cardio-vascular comorbidities; 54 % (n-296) had renal comorbidities including 22% (n-121) having had dialysis and 4.2% (n-23) with renal transplants. Eight of the 549 patients (1.5%) had suffered a VTE event of which only 2 (0.36%) were during the period of immobilization in TCC. One was a symptomatic DVT (0.18%) and the another was an asymptomatic (incidental) finding of pulmonary embolism (PE). There was no mortality related to the VTE episodes. Conclusion. NICE guidelines state that one should “Consider pharmacological VTE prophylaxis for patients with lower limb immobilization”. Our study finds that patients treated in a weight bearing TCC do not require routine pharmacological VTE prophylaxis, in spite of an extended period of lower limb immobilization and significant medical comorbidities