Deep Vein Thrombosis Prophylaxis after Total Hip Arthroplasty in Asian Patients

Incidence of Venous Thromboembolism after Primary Total Hip Arthroplasty with Mechanical Prophylaxis in Hong Kong Chinese

Purpose

The incidence of deep vein thrombosis (DVT) following total hip arthroplasty (THA) without chemoprophylaxis could be as high as 50% in Caucasians. However, according to several subsequent studies, the incidence of venous thromboembolic events (VTE) in Asians was much lower. The routine use of chemoprophylaxis, which could potentially cause increased bleeding, infection, and wound complications, has been questioned in low-incidence populations. The objective of this study is to determine the incidence of VTE after primary THA without chemoprophylaxis in an Asian population using a fast-track rehabilitation protocol and to verify the safety profile for use of 'mechanical prophylaxis alone' in patients with standard risk of VTE.

Materials and Methods

This is a retrospective cohort study of 542 Hong Kong Chinese patients who underwent primary THA without chemoprophylaxis. All patients received intermittent pneumatic compression and graduated compression stockings as mechanical prophylaxis. Multimodal pain management was applied in order to facilitate early mobilisation. Routine duplex ultrasonography was performed between the fourth and seventh postoperative day for detection of proximal DVT.

Results

All patients were Chinese (mean age, 63.0±11.9 years). Six patients developed proximal DVT (incidence rate, 1.1%). None of the patients had symptomatic or fatal pulmonary embolism.

Conclusion

The incidence of VTE after primary THA without chemical prophylaxis can be low in Asian populations when following a fast-track rehabilitation protocol. Mechanical prophylaxis alone can be regarded as a reasonably safe practice in terms of a balanced benefit-to-risk ratio for Asian patients with standard risk of VTE.

3D Printing of a Porous Zn-1Mg-0.1Sr Alloy Scaffold: A Study on Mechanical Properties, Degradability, and Biosafety

In recent years, the use of zinc (Zn) alloys as degradable metal materials has attracted considerable attention in the field of biomedical bone implant materials. This study investigates the fabrication of porous scaffolds using a Zn-1Mg-0.1Sr alloy through a three-dimensional (3D) printing technique, selective laser melting (SLM). The results showed that the porous Zn-1Mg-0.1Sr alloy scaffold featured a microporous structure and exhibited a compressive strength (CS) of 33.71 ± 2.51 MPa, a yield strength (YS) of 27.88 ± 1.58 MPa, and an elastic modulus (E) of 2.3 ± 0.8 GPa. During the immersion experiments, the immersion solution showed a concentration of 2.14 ± 0.82 mg/L for Zn2+ and 0.34 ± 0.14 mg/L for Sr2+, with an average pH of 7.61 ± 0.09. The porous Zn-1Mg-0.1Sr alloy demonstrated a weight loss of 12.82 ± 0.55% and a corrosion degradation rate of 0.36 ± 0.01 mm/year in 14 days. The Cell Counting Kit-8 (CCK-8) assay was used to check the viability of the cells. The results showed that the 10% and 20% extracts significantly increased the activity of osteoblast precursor cells (MC3T3-E1), with a cytotoxicity grade of 0, which indicates safety and non-toxicity. In summary, the porous Zn-1Mg-0.1Sr alloy scaffold exhibits outstanding mechanical properties, an appropriate degradation rate, and favorable biosafety, making it an ideal candidate for degradable metal bone implants.

Understanding factors that impact the length of stay after total hip arthroplasty - A national in-patient sample-based study

Background

Total hip arthroplasty (THA) is increasingly used every year; however, there is currently limited information on factors that impact the length of stay (LOS) following the procedure. Longer LOS following THA is met with an increase in the cost of care, necessitating studies to identify factors that may impact LOS.

Methods

In this retrospective study, we used the Nationwide Inpatient Sample (NIS) database from 2016 to 2019 to analyze the preoperative comorbidities and postoperative complications that impact the LOS following THA. We divided our cohort into patients with a LOS greater than two days, and patients with a LOS less than two days.

Results

A total of 367,890 patients were identified in the NIS database who underwent THA during the study period. Of this cohort, 112,288 (30.52%) patients were identified as having a LOS greater than two days, while the remaining 255,602 (69.48%) patients were patients who had a LOS less than two days. Multivariate analysis demonstrated several pre-operative factors, such as diabetes, systemic lupus erythematosus, organ transplant, dialysis, the human immunodeficiency virus, chronic kidney disease, and Parkinson's disease, were independently associated with a higher risk of a LOS greater than two days. The subsequent multivariate analysis for post-operative variables demonstrated that acute renal failure, myocardial infarction, blood loss anemia, blood transfusion, pulmonary embolism, deep vein thrombosis, periprosthetic fracture, periprosthetic mechanical complications, periprosthetic infections, and wound dehiscence were all independently associated with a higher risk of a LOS greater than two days.

Conclusions

Several pre-operative comorbidities and postoperative complications were found to increase the likelihood of a LOS greater than two days. In addition, the group with a LOS greater than two days incurred a higher cost of care. This information is useful for providers to make informed decisions regarding patient care and resource utilization for patients undergoing THA, potentially reducing LOS.

The effect of cocaine on patients undergoing total hip arthroplasty

Background

Cocaine use has surged in the past decade, with 4.8 million Americans (1.7% of the population greater than 12) reporting use in 2021, leading to a healthcare burden of 1.3 billion dollars. Cocaine users experience prolonged hospital stays, higher costs, worse surgical outcomes, increased risk of medical conditions, and inflammation-related osteoarthritis. The study aims to identify factors influencing length of stay, costs, and perioperative complications in cocaine users undergoing total hip arthroplasty (THA) to reduce these risks.

Methods

This study utilized the NIS database, providing comprehensive information on patient demographics, length of stay, hospital costs, and complications. Statistical analyses were conducted using SPSS software, including propensity matching and significance testing, to compare outcomes between cocaine users (CU) and non-cocaine users (NCU) undergoing total hip arthroplasty.

Results

After propensity matching, cocaine users had a significantly longer LOS (4.8 days) in comparison to non-cocaine users (2.6 days) (p < 0.001). Similarly, the CU group had a larger of care (87984.9) than the NCU group (69149.2) (p < 0.001). Cocaine users had significantly higher rates of blood loss anemia (OR: 3.24, 95% CI: 2.21, 4.73), blood loss anemia (OR: 1.59, 95% CI: 1.12, 2.24), blood transfusion (OR: 2.23, 95% CI: 1.04, 4.78), periprosthetic dislocation (OR: 6.57, 95% CI: 1.47, 29.32), and periprosthetic infection (OR: 4.59, 95% CI: 1.54, 13.68) than patients in the non-cocaine user's group.

Conclusion

Cocaine users had a significantly longer length of stay, higher costs of care, and an increased number of post-operative complications compared to non-cocaine users. These data contribute to understanding the potential ramifications of cocaine users undergoing THA.

Development and validation of a newly developed nomogram for predicting the risk of deep vein thrombosis after surgery for lower limb fractures in elderly patients

Background

Prevention of deep vein thrombosis (DVT) is indispensable in the treatment of lower limb fractures during the perioperative period. This study aimed to develop and validate a novel model for predicting the risk of DVT in elderly patients after orthopedic surgeries for lower limb fractures.

Methods

This observational study included 576 elderly patients with lower limb fractures who were surgically treated from January 2016 to December 2018. Eleven items affecting DVT were optimized by least absolute shrinkage and selection operator regression analysis. Multivariable logistic regression analysis was performed to construct a predictive model incorporating the selected features. C-index was applied to evaluate the discrimination. Decision curve analysis was employed to determine the clinical effectiveness of this model and calibration plot was applied to evaluate the calibration of this nomogram. The internal validation of this model was assessed by bootstrapping validation.

Results

Predictive factors that affected the rate of DVT in this model included smoking, time from injury to surgery, operation time, blood transfusion, hip replacement arthroplasty, and D-dimer level after operation. The nomogram showed significant discrimination with a C-index of 0.919 (95% confidence interval: 0.893-0.946) and good calibration. Acceptable C-index value could still be reached in the interval validation. Decision curve analysis indicated that the DVT risk nomogram was useful within all possibility threshold.

Conclusion

This newly developed nomogram could be used to predict the risk of DVT in elderly patients with lower limb fractures during the perioperative period.

The Risk Factors for New-Onset Calf Muscle Venous Thrombosis after Hip Fracture Surgery

BACKGROUND

Calf muscle venous thrombosis (CMVT) is among the most important medical complications after hip surgery. CMVT has been known for many years, but many opinions about the incidence and risk factors of CMVT are still controversial. The objective of this retrospective study was to investigate the incidence and associated risk factors of postoperative CMVT in patients with hip fractures.

METHODS

Patients with hip fractures from January 2020 to April 2022 (n = 320) at Shenzhen Second People's Hospital were recruited in this study. The personal characteristics and clinical data of CMVT and no-CMVT patients were compared and analyzed. Binary logistic regression analyses were performed to identify potential risk factors of CMVT in patients with hip fractures. Finally we performed a receiver operating characteristic (ROC) curve analysis to compare the diagnostic values of different variables.

RESULTS

The overall incidence of new-onset CMVT in patients with hip fractures was 18.75% (60 of 320). Among the 60 CMVT patients, 70% (42 of 60) were diagnosed with femoral neck fractures, 28.3% (17 of 60) with intertrochanteric fractures, and 1.7% (1 of 60) with subtrochanteric fractures. No pulmonary embolism (PE) occurred. High preoperative D-dimer (OR = 1.002, 95%CI 0.97-1.03), sex (OR = 1.22, 95%CI 0.51-2.96), the caprini score (OR = 2.32, 95%CI 1.05-5.16) and the waterlow score (OR = 1.077, 95%CI 0.35-3.36) significantly increased the risk of developing postoperative new-onset CMVT.

CONCLUSIONS

CMVT has become a common clinical disease, and its harm should not be underestimated. Our study found that D-dimer, sex, the caprini score and the waterlow score were independent risk factors for postoperative CMVT. According to our clinical work, we should pay attention to identifying the risk factors of CMVT formation and targeted intervention measures to prevent new-onset CMVT.

Study on the correlation between high density lipoprotein and lower extremities deep venous thrombosis in patients undergoing hip arthroplasty

OBJECTIVE

To explore the relationship between high density lipoprotein (HDL) and lower extremities deep venous thrombosis (DVT) in patients undergoing hip arthroplasty.

METHODS

A total of 348 patients undergoing hip arthroplasty in our hospital were enrolled, and divided into observation (n = 154, 44.25%) and control (n = 194, 55.75%) groups according to the occurrence of lower extremities DVT. The presence of DVT was assessed 1 day before surgery and routinely every 2 days after surgery. The factors of DVT were analyzed by single factor analysis, multivariate logistic regression analysis, and Pearson correlation.

RESULTS

The age and body mass index in the observation group were significantly higher (p = .045, p = .041, respectively), while HDL-C was significantly lower (p = .032) than the control group. Increase age, high BMI, low apolipoprotein-A1 level and low HDL-C level were risk factors for lower extremities DVT. The mean HDL-C in the observation and control groups was 0.91 ± 0.27 and 1.19 ± 0.37, respectively, the adjusted odds ratio was 1.050; 95% CI 1.010-1.092, p = .014.

CONCLUSION

Elderly patients with high BMI and low HDL-C level undergoing hip arthroplasty are at risk of lower extremities DVT, and should be paid attention to clinically.

Rotational Thromboelastometry Findings Are Associated with Symptomatic Venous Thromboembolic Complications after Hip Fracture Surgery

BACKGROUND

Venous thromboembolism is a common complication after hip fractures. However, there are no reliable laboratory assays to identify patients at risk for venous thromboembolic (VTE) events after major orthopaedic surgery.

QUESTION/PURPOSES

(1) Are rotational thromboelastometry (ROTEM) findings associated with the presence or development of symptomatic VTE after hip fracture surgery? (2) Were any other patient factors associated with the presence or development of symptomatic VTE after hip fracture surgery? (3) Which ROTEM parameters were the most accurate in terms of detecting the association of hypercoagulability with symptomatic VTE?

METHODS

This retrospective study was conducted over a 13-month period. In all, 354 patients with femoral neck and peritrochanteric fractures who underwent hip hemiarthoplasty or cephallomedullary nailing were assessed for eligibility. Of those, 99% (349 of 354) were considered eligible for the study, 1% (3 of 354) of patients were excluded due to coagulation disorders, and another 1% (2 of 354) were excluded because they died before the postoperative ROTEM analysis. An additional 4% (13 of 354) of patients were lost before the minimum study follow-up of 3 months, leaving 95% (336 of 354) for analysis. A ROTEM analysis was performed in all patients at the time of their hospital admission, within hours of the injury, and on the second postoperative day. The patients were monitored for the development of symptoms indicative of VTE, and the gold standard tests for diagnosing VTE, such as CT pulmonary angiography or vascular ultrasound, were selectively performed only in symptomatic patients and not routinely in all patients. Therefore, this study evaluates the association of ROTEM with only clinically evident VTE events and not with all VTE events. ROTEM results did not affect the clinical surveillance of the study group and the decision for further work up. To determine whether ROTEM findings were associated with the presence or development of symptomatic VTE, ROTEM parameters were compared between patients with and without symptomatic VTE. To establish whether any other patient factors were associated with the presence or development of symptomatic VTE after hip fracture surgery, clinical parameters and conventional laboratory values were also compared between patients with and without symptomatic VTE. Finally, to determine which ROTEM parameters were the most accurate in terms of detecting the association of hypercoagulability with symptomatic VTE, the area under the curve (AUC) for certain cut off values of ROTEM parameters was calculated.

RESULTS

We found several abnormal ROTEM values to be associated with the presence or development of symptomatic VTE. The preoperative maximum clot firmness was higher in patients with clinically evident VTE than in patients without these complications (median [interquartile range] 70 mm [68 to 71] versus 65 mm [61 to 68]; p < 0.001). The preoperative clot formation time was lower in patients with clinically evident VTE than those without clinically evident VTE (median 61 seconds [58 to 65] versus 70 seconds [67 to 74]; p < 0.001), and also the postoperative clot formation time was lower in patients with clinically evident VTE than those without these complications (median 52 seconds [49 to 59] versus 62 seconds [57 to 68]; p < 0.001). Increased BMI was also associated with clinically evident VTE (odds ratio 1.26 [95% confidence interval 1.07 to 1.53]; p < 0.001). We found no differences between patients with and without clinically evident VTE in terms of age, sex, smoking status, comorbidities, and preoperative use of anticoagulants. Lastly, preoperative clot formation time demonstrated the best performance for detecting the association of hypercoagulability with symptomatic VTE (AUC 0.89 [95% CI 0.81 to 0.97]), with 81% (95% CI 48% to 97%) sensitivity and 86% (95% CI 81% to 89%) specificity for clot formation time ≤ 65 seconds.

CONCLUSION

ROTEM's performance in this preliminary study was promising in terms of its association with symptomatic VTE. This study extended our earlier work by demonstrating that ROTEM has a high accuracy in detecting the level of hypercoagulability that is associated with symptomatic VTE. However, until its performance is validated in a study that applies a diagnostic gold standard (such as venography, duplex/Doppler, or chest CT) in all patients having ROTEM to confirm its performance, ROTEM should not be used as a regular part of clinical practice.

LEVEL OF EVIDENCE

Level IV, diagnostic study.

Hospital-Acquired Conditions: A Review of Classical and Novel Risk Factors Following Total Hip and Knee Arthroplasties

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In 2016, a total of 48,771 hospital-acquired conditions (HACs) were reported in U.S. hospitals. These incidents resulted in an excess cost of >$2 billion, which translates to roughly $41,000 per patient per HAC.

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In the settings of total hip arthroplasty (THA) and total knee arthroplasty (TKA), increased age, a body mass index of >35 kg/m2, male sex, diabetes mellitus, electrolyte disturbances, and a history of anemia increase the likelihood of surgical site infections.

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Institution-specific (surgical) risk factors such as increased tourniquet time, an operative time of >130 minutes, bilateral procedures, a femoral nerve block, and general anesthesia increase the risk of HACs in the settings of THA and TKA.

The deep vein thrombosis of lower limb after total hip arthroplasty: what should we care

Background

Deep vein thrombosis (DVT) of lower limb is one of the common complications after total hip arthroplasty(THA), we aimed to evaluate the potential risk factors of DVT of lower limb in patients with THA, to provide insights into the management of THA.

Methods

Patients who underwent THA in our hospital from January 1, 2017 to November 30, 2020 were included. The personal characteristics and clinical data of DVT and no-DVT patients were compared and analyzed. Logistic regression analyses were perfomed to identify the potential risk factors of DVT in patients with THA.

Results

A total of 182 THA patients were included, the incidence of DVT of lower limb in patients with THA was 19.78 %. There were significant differences in the age, BMI, diabetes, number of replacement, duration of surgery, type of prosthesis and duration of days in bed between DVT and no-DVT patients(all P < 0.05). And there were no significant differences in the gender, hypertension, hyperlipidemia, preoperative D-dimer, type of anesthesia and anticoagulant drugs use(all P > 0.05). Logistic regression analysis indicated that age > 70y(OR4.406, 95 %CI1.744 ~ 6.134), BMI ≥ 28(OR2.275, 95 %CI1.181 ~ 4.531), diabetes(OR3.949, 95 %CI1.284 ~ 5.279), bilateral joint replacements(OR2.272, 95 %CI1.402 ~ 4.423), duration of surgery ≥ 120 min(OR3.081, 95 %CI1.293 ~ 5.308), cemented prosthesis(OR2.435, 95 %CI1.104 ~ 4.315), and duration of days in bed > 3 days(OR1.566, 95 %CI1.182 ~ 1.994) were the risk factors of DVT of lower limb in patients with THA.

Conclusions

DVT in the lower limb after THA is common, and its onset is affected by many factors. In clinical work, attention should be paid to identify the risk factors for DVT and targeted interventions are highlighted to prevent the postoperative DVT.

Impact of clinical pharmacist services on anticoagulation management of total joint arthroplasty: A retrospective observational study

WHAT IS KNOWN AND OBJECTIVE

Even if total joint arthroplasty (TJA) patients have received conventional antithrombotic therapy, the incidence of thrombosis remains high. Clinical pharmacists have been involved in the multidisciplinary team of orthopaedics, but their roles and functions are not yet defined. The objective of this study was to assess the impact of clinical pharmacist services on the use of anticoagulant drugs, the rationality of medication and the incidence of thrombosis in patients with TJA.

METHODS

This retrospective, observational cohort study was conducted for patients undergoing TJA procedures. Study variables were collected for a baseline period of 1 January 2016 to 30 June 2017 and an intervention period of 1 January 2018 to 30 June 2019, allowing for a 6-month run-in period. For demographic characteristics, the use of anticoagulant drugs and the incidence of thrombosis between the baseline and intervention periods, the data were statistically analysed.

RESULTS AND DISCUSSION

During the 36-month study timeframe, a total of 591 TJA procedures were performed. A total of 577 participants were included in the study (240 in the baseline group and 377 in the intervention group). After clinical pharmacist participation, the prevention rate of anticoagulant drugs (p < 0.05), the proportion of oral anticoagulants (p = 0.000) and the course of preventive treatment (p = 0.004) increased significantly. The time of administration was shortened from after 24 h to within 24 h post-surgery (p = 0.000). Although the incidence of symptomatic DVT reduced in the intervention period, there was no statistical difference in either the hospital, 1-month follow-up, or 3-month follow-up after surgery (all p > 0.05).

WHAT IS NEW AND CONCLUSION

Within the limitations of a retrospective study, clinical pharmacist intervention was associated with improvements in anticoagulation management of TJA procedures, likely conferring beneficial effects.

Is the Oral Chemical Prophylaxis Necessary for the Prevention of Venous Thromboembolism after Joint Arthroplasty in a Korean Population?

Purpose

Venous thromboembolism (VTE) is a serious complication that may occur after a major orthopedic surgery. The aim of the present study was to determine the necessity of a chemical thromboprophylactic agent (rivaroxaban [RXB]) by analyzing the prevalence of VTE in Korean arthroplasty patients who received RXB for prophylaxis compared with those who did not receive RXB.

Materials and Methods

A total of 2,603 patients who underwent knee or hip arthroplasty between 1996 and 2017 were prospectively evaluated. Of these, 1,608 patients underwent surgery before January 2010 and were not administered any type of prophylaxis after surgery; the remaining 995 underwent surgery after 2010 and received oral RXB once daily for 5–13 days from the day after hemovac drain removal to postoperative day 14.

Results

The primary study outcome was the prevalence of VTE, pulmonary embolism or death during follow up. The overall incidence of VTE was 1.69% (n=44); of these, 12 occurred in the RXB group and 32 in the non-prophylactic group. The odds ratio of VTE in the RXB group was 0.61. However, the statistical power of the study was 0.313 due to the low incidence of VTE.

Conclusion

Treatment with oral chemical prophylaxis decreased the incidence of VTE after knee or hip arthroplasty in a Korean population. Furthermore, no serious complications occurred after administering oral RXB, which, coupled with its convenience, suggests oral RXB offers an attractive alternative to other agents. However, we recommend that further studies, including a multicenter study, be conducted to achieve adequate statistical power.