Chemoprophylaxis for Venous Thromboembolism in Operative Treatment of Fractures of the Tibia and Distal Bones: A Systematic Review and Meta-analysis

Enoxaparin and Early Postoperative Tibial Nailing: Increased Nonunion Revision Rates

OBJECTIVES

To determine the association between postoperative enoxaparin use and the risk of requiring surgery for nonunion in patients treated with intramedullary nailing for midshaft fractures of the tibia.

METHODS

DESIGN

Retrospective cohort analysis.

SETTING

Data were sourced from the PearlDiver national database.

PATIENT SELECTION CRITERIA

Patients were identified through the PearlDiver database by using Current Procedural Terminology and International Classification of Diseases (ICD-10) codes. Included patients had undergone intramedullary nailing for midshaft fractures of the tibia between 2015 and 2020 and subsequently underwent revision surgery due to nonunion.

OUTCOME MEASURES AND COMPARISONS

The primary outcome measured in this study was the rate of nonunion following intramedullary nailing for the different types of tibial shaft fractures (closed, Type I/II open, Type III open). For each fracture subtype, the study compared nonunion rates between those who received enoxaparin in the postoperative period and those who did not receive enoxaparin at any time during the first 6 weeks postoperatively. Factors such as the timing and duration of enoxaparin therapy and demographic variables were also considered.

RESULTS

The study included 16,986 patients, average age was 49.2 years (SD 17.3); 43.1% were female. Five hundred four patients required revision surgery for nonunion (3.4%). Among patients who did not receive enoxaparin, the nonunion rates were 1.6%, 3.9%, and 6.9% for closed, Type I/II open, and Type III open fractures, respectively. For patients who received enoxaparin within the first 2 weeks, the nonunion rates were 2.6%, 4.7%, and 7.9% for closed (RR = 1.67, P < 0.0001), Type I/II open (RR = 1.21, P < 0.0001), and Type III open (RR = 1.17, P = 0.355) fractures, respectively. Logistic regression confirmed enoxaparin was independently associated with nonunion (odds ratios [OR] = 1.75, P = 0.0013 for closed fractures; OR = 1.51, P = 0.034 for Type I/II open fractures). Tobacco use was also a contributing factor (OR = 2.43, P < 0.0001 for closed fractures; OR = 2.00, P < 0.0001 for Type I/II open fractures; OR = 2.04, P = 0.0008 for Type III open fractures).

CONCLUSIONS

The postoperative use of enoxaparin was associated with an elevated risk of nonunion in patients treated with intramedullary nailing for fractures of the tibial shaft.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Update on Venous Thromboembolism in Orthopaedic Trauma Surgery

Venous thromboembolism (VTE) is a notable contributor to the morbidity and mortality of patients with orthopaedic trauma. Several associations have published guidelines on VTE prophylaxis, with a strong predilection toward low-molecular-weight heparin for chemoprophylaxis. However, previous recommendations may be revisited because recent high-level evidence demonstrated aspirin to be noninferior to low-molecular-weight heparin in preventing serious complications of VTE. Direct oral anticoagulants are emerging as safe alternatives to injectable medication and may offer improved patient compliance. There is no consensus on postinjury duration of chemoprophylaxis as an outpatient. Mechanical prophylaxis remains an important adjunctive VTE preventive measure for inpatients with pelvis and extremity fractures. Proteomics and novel laboratory measurements may be able to predict high-risk patients and detect early thrombus formation. Despite high-quality prospective research over the past decade, we still have much to learn about patient- and injury-specific risk factors.

Effect of Obesity on Short- and Long-Term Complications After Ankle Fracture Fixation

OBJECTIVES

This study evaluated the relationship between obesity and postoperative complications in patients undergoing ankle open reduction internal fixation (ORIF).

METHODS

DESIGN

Retrospective cohort study.

SETTING

PearlDiver-Mariner All-Payor Database.

PATIENT SELECTION CRITERIA

Patients who underwent ankle ORIF from 2010 to 2021 and had a minimum of 2 years of follow-up were identified using Current Procedural Terminology, ICD-9, and ICD-10 codes.

OUTCOME MEASURES AND OUTCOMES

Patients were stratified by body mass index into nonobese, obese, morbidly obese, and super-obese groups. Complication rates, including 90-day readmissions, infection, and post-traumatic osteoarthritis, were compared between obesity groups. Patients were additionally compared with a 1:1 matched analysis that controlled for demographics and comorbidities.

RESULTS

A total of 160,415 patients undergoing ankle ORIF from 2010 to 2021 were identified. The cohort consisted mostly of females (64.8%) and the average age was 52.5 (SD 18.4) years. There were higher rates of 90-day readmissions, UTIs, DVT/PE, pneumonia, superficial infections, and acute kidney injuries in patients with increasing levels of obesity (P < 0.001). There were increased odds of nonunion and post-traumatic arthritis in the matched analysis at 2 years in the obesity group [OR: 2.36, 95% confidence interval (CI): 1.68-3.31, P < 0.001; OR: 2.18, 95% CI: 1.77-2.68, P < 0.001, respectively].

CONCLUSIONS

Postoperative medical complication rates in patients undergoing ankle ORIF, including infection, are higher in obese patients, even in the 1:1 matched analysis that controlled for demographic and comorbidity factors. Rates of nonunion and post-traumatic arthritis were higher in obese patients, as well. As such, it is important for surgeons to provide appropriate education regarding the risks after ankle ORIF in patients with obesity.

LEVEL OF EVIDENCE

Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Venous thromboembolism in patients with surgically treated ankle fractures

OBJECTIVES

In patients with rotational ankle fracture, we compare the rate of venous thromboembolism development between patients who received chemoprophylaxis vs those patients that received none.

DESIGN

Retrospective cohort study.

SETTING

Level I trauma center.

PATIENTS/PARTICIPANTS

Between 2014 and 2018, we identified 483 patients with rotational ankle fracture that had no VTE risk factors, were under 70 years of age, and had an isolated injury.

INTERVENTION

Chemoprophylaxis vs no chemoprophylaxis after open reduction internal fixation of a rotational ankle fracture.

MAIN OUTCOME MEASUREMENTS

Development of VTE was the primary outcome. Secondary outcomes included wound problems, infection, hematoma, or non-union.

RESULTS

There were 313 patients that received no prophylaxis and 170 patients that received chemoprophylaxis after operative fixation of an isolated ankle fracture. Demographics including age, gender, body mass index, and ASA class were similar between groups. The rate of DVT/PE was 3.5% in those without DVT prophylaxis, and 4.1% in those on DVT prophylaxis with no significant differences found (p = 0.8). There was no significant difference in wound complication (no VTE prophylaxis-3.7% vs VTE prophylaxis-2.5%, p = 0.7) or infection rates (no VTE prophylaxis-3.8% vs VTE prophylaxis 4.1%, p = 1.0) between groups.

CONCLUSIONS

No difference was detected in the rate of symptomatic DVT or PE in patients based on chemoprophylaxis. Our results support the conclusion that the use of chemoprophylaxis may remain surgeon preference and based on patient risk factors for VTE development.

LEVEL OF EVIDENCE

Level III-retrospective cohort study.

A Prospective Randomized Controlled Trial Comparing Enoxaparin & Rivaroxaban for Venous Thromboembolism Prophylaxis in Orthopaedic Trauma

OBJECTIVES

To determine whether there is a difference in orthopaedic trauma patient medication satisfaction and adherence using an oral versus subcutaneous injectable anticoagulant for venous thromboembolism chemoprophylaxis.

DESIGN

Randomized controlled trial.

SETTING

Single academic Level 1 trauma center.

PARTICIPANTS

One hundred twenty adult orthopaedic trauma patients with operative pelvic or lower extremity fractures were randomized and completed the study.

INTERVENTION

Three weeks of either the service standard 40 mg once daily enoxaparin versus trial medication 10 mg once daily rivaroxaban postoperatively.

MAIN OUTCOME MEASURES

Patient satisfaction as measured by the Treatment Satisfaction Questionnaire for Medication (TSQM-9). Medication adherence as measured by the Morisky Medication Adherence Scale (MMAS-8).

RESULTS

Medication adherence was similar in both groups. Medication satisfaction was significantly higher in the oral rivaroxaban group based on the TSQM-9 and patient-reported data. Secondary outcomes found no significant difference in the incidence of bleeding events or clinically relevant venous thromboembolism. The enoxaparin group experienced more adverse medication-related events. The rivaroxaban medication regimen costs 7.5-10× less out of pocket for uninsured patients.

CONCLUSION

The results of this randomized controlled trial demonstrate that patients with surgical orthopaedic trauma prefer an oral anticoagulant for postoperative venous thromboembolism chemoprophylaxis and suggest that rivaroxaban may be a viable option. Furthermore, large-scale studies are needed to confirm safety and efficacy for rivaroxaban in this population as a potential alternative to enoxaparin and aspirin.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Incidence and risk factors of clinically important venous thromboembolism in tibial plateau fractures

While there are multiple reports on venous thromboembolism (VTE) associated with several orthopedic procedures, the knowledge regarding incidence and risk factors of VTE in tibial plateau fractures is limited. This study aimed to investigate the incidence and risk factors of clinically important venous thromboembolism (CIVTE) in patients with tibial plateau fractures. All adult patients who underwent surgical treatment of tibia plateau fractures between 2003 and 2018 in our level 1 trauma center were included in the study. All patients suspected CIVTE were assessed by the ultrasonography and/or CT scan. Univariate and multivariate analysis were used to evaluate the association between potential risk factors and CIVTE Variables. Thirty-nine of 462 patients (8.4%) developed clinically important venous thromboembolism, in which pulmonary embolism (PE) and deep vein thrombosis (DVT) were observed in 18 (3.9%) and 21 (4.54%) patients, respectively. Male gender (OR 9.75; 95% CI 2.34-40.66), spine injury (OR 9.51; 95% CI 3.39-26.64), other extremity injury (OR 3.7; 95% CI 1.58-8.66), length of stay in ICU (OR 1.14; 95% CI 1.09-1.2) were all risk factors for CIVTE. The incidence of CIVTE in tibial plateau fracture was relatively high (8.4%); The male gender, spine injury, other extremity injury, length of stay in ICU were the independent risk factors.

Qualitative analysis of randomized controlled trials informing recommendations for venous thromboembolism prophylaxis after distal lower extremity injuries

Purpose:

The purpose of this study is to assess the quality of evidence to stratify recommendations for chemoprophylaxis following distal lower extremity trauma.

Methods:

Literature review identified primary studies investigating venous thromboembolism (VTE) chemoprophylaxis following traumatic injury distal to the knee. Inclusion criteria were randomized controlled trials in adult patients treated with and without operative intervention. Each primary study was assessed by the Consolidated Standards of Reporting Trials 2010 checklist and Modified Coleman methodology score.

Results:

Literature review resulted in 462 studies, of which 9 met inclusion and exclusion criteria. All studies included low molecular weight heparin as a treatment group with 2 (22%) also including a treatment group with a direct factor Xa inhibitor. Five studies (56%) used placebo as a control group. The mean Modified Coleman Methodology score was 63% (range 51%–72%), a categorical rating of Fair. The mean Consolidated Standards of Reporting Trials score was 78% (range 56%–97%). Most studies (89%) screened all asymptomatic subjects for deep venous thrombosis. Statistical significance in VTE incidence among prophylactic treatment groups was not achieved in 78%.

Conclusions:

Development of consensus for VTE prophylaxis recommendations following traumatic injury distal to the knee is complicated by heterogenous study populations, low incidence of VTE in study populations, and inconsistent definitions of clinically important VTE. Low molecular weight heparin is not consistently superior for preventing VTE. Chemoprophylaxis should be considered on an individual basis in the presence of additional risk factors, although an externally validated, evidence-based risk assessment tool does not currently exist.

Level of Evidence: IV, therapeutic

The Effectiveness and Safety of Direct Oral Anticoagulants Following Lower Limb Fracture Surgery: A Systematic Review and Meta-analysis

OBJECTIVES

Venous thromboembolism (VTE) is a well-established complication after many orthopaedic injuries, such as hip and lower limb fractures. The use of direct oral anticoagulants (DOACs, previously termed novel oral anticoagulants) is well-established as thromboprophylaxis after major elective orthopaedic surgery, but not in the nonelective setting. The aim of this study was to investigate the effectiveness and safety of DOACs after nonelective lower limb fracture surgery.

DATA SOURCES

A systematic literature search of the MEDLINE, EMBASE, CINAHL, and CENTRAL databases was conducted. No limitation was placed on publication date, with only manuscripts printed in English were eligible.

STUDY SELECTION

Included studies were either randomized controlled trials or prospective and retrospective comparative studies. Included studies compared DOACs to conventional methods of thromboprophylaxis in the postoperative period after surgical management of lower limb fractures.

DATA EXTRACTION

Outcomes included VTE, bleeding, wound complications, mortality, and adverse events. Eight studies met inclusion criteria, of which 7 compared direct factor Xa inhibitors (XaIs) with conventional VTE prophylaxis and one study compared a direct thrombin inhibitor with conventional VTE prophylaxis.

DATA SYNTHESIS

Revman 5.3 (Nordic Cochrane Centre, Denmark) was used to complete the meta-analysis and generate forest plots.

CONCLUSIONS

XaIs were shown to have lower rates of deep vein thrombosis (Odds ratio 0.59; 95% confidence interval, 0.46-0.76; P < 0.0001) and less pharmacologically attributable adverse events (Odds ratio 0.62; 95% confidence interval, 0.46-0.82; P = 0.0007). There was difference between DOACs and conventional VTE prophylaxis regarding mortality, PE, symptomatic deep vein thrombosis, or bleeding events. The results generally support the use of DOACs for VTE prophylaxis after nonelective lower limb fracture surgery, such after hip fracture. The results more strongly support the use of XaIs; however, more evidence is needed to fully assess DOACs' role in clinical practice.

LEVEL OF EVIDENCE

Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Incidence and risk factors for deep venous thrombosis of lower extremity after surgical treatment of isolated patella fractures

Background

Limited information exists on the incidence of postoperative deep venous thromboembolism (DVT) in patients with isolated patella fractures. The objective of this study was to investigate the postoperative incidence and locations of deep venous thrombosis (DVT) of the lower extremity in patients who underwent isolated patella fractures and identify the associated risk factors.

Methods

Medical data of 716 hospitalized patients was collected. The patients had acute isolated patella fractures and were admitted at the 3rd Hospital of Hebei Medical University between January 1, 2016, and February 31, 2019. All patients met the inclusion criteria. Medical data was collected using the inpatient record system, which included the patient demographics, patient’s bad hobbies, comorbidities, past medical history, fracture and surgery-related factors, hematological biomarkers, total hospital stay, and preoperative stay. Doppler examination was conducted for the diagnosis of DVT. Univariate analyses and multivariate logistic regression analyses were used to identify the independent risk factors.

Results

Among the 716 patients, DVT was confirmed in 29 cases, indicating an incidence of 4.1%. DVT involved bilateral limbs (injured and uninjured) in one patient (3.4%). DVT involved superficial femoral common vein in 1 case (3.4%), popliteal vein in 6 cases (20.7%), posterior tibial vein in 11 cases (37.9%), and peroneal vein in 11 cases (37.9%). The median of the interval between surgery and diagnosis of DVT was 4.0 days (range, 1.0-8.0 days). Six variables were identified to be independent risk factors for DVT which included age category (> 65 years old), OR, 4.44 (1.34-14.71); arrhythmia, OR, 4.41 (1.20-16.15); intra-operative blood loss, OR, 1.01 (1.00-1.02); preoperative stay (delay of each day), OR, 1.43 (1.15-1.78); surgical duration, OR, 1.04 (1.03-1.06); LDL-C (> 3.37 mmol/L), OR, 2.98 (1.14-7.76).

Conclusion

Incidence of postoperative DVT in patients with isolated patella fractures is substantial. More attentions should be paid on postoperative DVT prophylaxis in patients with isolated patella fractures. Identification of associated risk factors can help clinicians recognize the risk population, assess the risk of DVT, and develop personalized prophylaxis strategies.

Thromboprophylaxis in Intramedullary Limb Lengthening Surgery

Aim

The use of intramedullary lengthening devices is becoming increasingly popular. There are limited data regarding the incidence of venous thromboembolism following intramedullary lengthening surgery and no reports or guidance for current practice on use of thromboprophylaxis. Following a case of post-operative deep vein thrombosis in our institution, we felt that it is important to assess best practice. We conducted a national survey to collect data that would describe current practice and help develop consensus for treatment.

Materials and methods

We identified surgeons across the UK that perform adult intramedullary limb lengthening through the British Limb Reconstruction Society membership and a Precise Users database. Surgeons were contacted and asked to respond to an online survey. Responses to thromboprophylaxis regimes employed in their practice and cases of venous thromboembolism were collated.

Results

24 out of 54 surgeons identified responded with a total of 454 cases of adult intramedullary lengthening (352 femoral and 102 tibial nails) performed over a five year period (January 2015–January 2020). Only one case of deep venous thrombosis (DVT) following femoral lengthening was reported. There is wide variability in practice both in terms of thromboprophylaxis risk assessment, choice of medications and duration of treatment. The vast majority of surgeons (85%) felt that there was insufficient evidence available to guide their practice.

Conclusions

Intramedullary lengthening is a surgical treatment growing in popularity. There are limited data available to guide decision-making regarding aspects of treatment such as thromboprophylaxis. This is reflected in the wide variation in practice reported in this study. There are both a need and a desire to gather data that will allow us to come to a consensus and to guide safe practice.

Clinical significance

Venous thromboembolism is a potential complication of lower limb lengthening surgery. We report on national incidence and current practices of thromboprophylaxis to allow for informed decision-making and help develop consensus for best practice.

How to cite this article

Iliadis AD, Timms A, Fugazzotto S, et al. Thromboprophylaxis in Intramedullary Limb Lengthening Surgery. Strategies Trauma Limb Reconstr 2020;15(3):151-156.

Venous thromboembolism rates remained unchanged in operative lower extremity orthopaedic trauma patients from 2008 to 2016

BACKGROUND

Venous thromboembolism (VTE) is a serious complication that contributes to morbidity, mortality, and healthcare costs during the surgical care of patient with lower extremity fractures. Despite this, few recommendations on the topic exist and the literature on VTE incidence is incomplete. Therefore, this study will attempt to estimate annual incidence and trends in 30-day thrombotic events and mortality for the following fractures: (1) hip, (2) femur, (3) patella, (4) tibia and/or fibula, and (5) ankle.

METHODS

We identified 120,521 operative lower extremity orthopaedic trauma patients from 2008 to 2016 using the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database. To evaluate the relationship between the year in which surgery was performed and comorbidities and demographic information bivariate analysis was performed. Bivariate analysis was also performed for the outcomes of interest and year in which the surgery was performed to assess for change. Additionally, bimodal multivariate logistic regression models for hip, femur, and ankle fractures were built, comparing the years 2009 to 2016 using 2008 as a baseline.

RESULTS

Overall incidence for VTE over the study period was 1.7% for hip fractures, 2.4% for femur fractures, 0.9% for patella fractures, 1.1% in tibia and/or fibula fractures, and 0.6% in ankle fractures. Over the study period VTE incidence saw a significant decrease (p < 0.05) in hip and femur fractures, but not for patella, tibia and/or fibula, and ankle fractures. After adjusting for confounding factors with multivariate analysis, the change in hip and femur fractures was no longer significant, while no significant decrease was again found for ankle fractures (p > 0.05).

CONCLUSION

Our study demonstrates that VTE rates have remained unchanged in operative lower extremity orthopaedic trauma from 2008 to 2016. This highlights the need for higher quality evidence on this important topic in orthopaedic trauma, including a reevaluation on the necessity of thromboprophylaxis guidelines.

LEVEL OF EVIDENCE

III.

Chemoprophylaxis for the Hip Fracture Patient: A Comparison of Warfarin and Low-Molecular-Weight Heparin

OBJECTIVE

To compare the rates of deep venous thrombosis (DVT), rates of pulmonary embolus (PE), and complication profiles of warfarin and low-molecular-weight heparin (LMWH) in patients undergoing operative fixation of hip fractures.

DESIGN

Retrospective cohort study.

SETTING

Insurance-based database of more than 22 million patient records.

PATIENTS

Adult hip fracture patients who were treated operatively and received chemoprophylaxis from 2007 to 2016. A total of 7594 patients met inclusion criteria and were available for final analysis.

INTERVENTION

Pharmacological anticoagulation with warfarin or LMWH to prevent postoperative venous thromboembolism after hip fracture surgery.

MAIN OUTCOME MEASURES

Development of DVT or PE within 30 and 90 days of surgery.

RESULTS

Patients prescribed warfarin had higher rates of DVT and PE compared with those prescribed LMWH. Patients on warfarin were more likely to develop a postoperative hematoma and to be readmitted within 30 and 90 days compared with those on LMWH. Patients in both groups had similar rates of total complications.

CONCLUSIONS

Patients prescribed warfarin after hip fractures had higher rates of DVT and PE compared with those prescribed LMWH, although both agents had similar complication profiles.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.