Low-Dose Aspirin Is Adequate for Venous Thromboembolism Prevention Following Total Joint Arthroplasty: A Systematic Review

Low-versus high-dose aspirin for venous thromboembolic prophylaxis after total joint arthroplasty: a systematic review and meta-analysis

BACKGROUND

The adverse effects of aspirin are dose-dependent, and there is controversy surrounding the use of low-dose (LD) aspirin to prevent venous thromboembolism (VTE) following total joint arthroplasty (TJA). This meta-analysis sought to compare the efficacy and complication rate of low-dose (162 mg per day) versus high-dose (HD, 650 mg per day) aspirin after TJA surgery.

METHODS

In four main databases, we searched from inception until September 2024 for articles comparing the rate of VTE following TJA(TKA/THA) using only aspirin chemoprophylaxis with different dosages. We meta-analyzed and compared the VTE and complication rates of LD aspirin (162 mg per day) with HD aspirin (650 mg per day) and presented our results as odds ratio (ORs) in forest plot diagrams.

RESULTS

There were 14 eligible studies, comprising 43,518 patients in the LD group and 62,645 patients in the HD group. DVT (OR: 1.37, CI: 0.93-2.02, P = 0.11) and PE (OR: 1.86, CI: 0.73-4.72, P = 0.19) rates were similar between the groups. However, taking VTE as the total number of cases with DVT or PE, the incidence was significantly higher in the HD group than in the LD group (OR:1.53, CI: 1.17-2.00, P = 0.002). HD also had a significantly higher rate of PJI (OR:2.68 CI:1.5-4.6 P = 0.001), but gastrointestinal bleeding (GIB) was similar between the two groups (OR: 0.97, CI: 0.42-2.22, P = 0.95).

CONCLUSION

The findings suggest that LD aspirin may be a viable option for VTE chemoprophylaxis following TJA, potentially offering comparable efficacy with a lower risk of PJI compared to HD aspirin regimens.

LEVEL OF EVIDENCE

Therapeutic Level II.

Aspirin as Venous Thromboembolism Prophylaxis in Arthroplasty Patients: An Analysis of Clinical Practice Guidelines Recommendations

BACKGROUND

Venous thromboembolism (VTE) is a recognized postoperative complication of hip or knee arthroplasty and incurs major morbidity and mortality. While anticoagulants are the mainstay of chemoprophylaxis, aspirin has recently emerged as a popular prophylactic agent. However, there is a lack of high-quality evidence comparing aspirin to anticoagulants as a method of VTE prophylaxis, and current guidelines are conflicting regarding using aspirin as first-line chemoprophylaxis. We aimed to investigate guideline characteristics that are associated with the recommendation for or against aspirin as a first-line agent.

METHODS

MEDLINE, Embase, Cumulative Index to Nursing and Allied Health Literature, and PubMed databases were searched from 1966 to January 2024 to identify clinical practice guidelines for VTE prophylaxis in adult hip or knee arthroplasty inpatients of average risk. The characteristics of the guideline were collected by 2 independent reviewers. Logistic regression was used to test the association between the recommendation for or against aspirin and guideline characteristics.

RESULTS

There were 26 guidelines published from February 2003 to September 2023 and included in this study. There were 5 guidelines that recommended aspirin and 11 guidelines that recommended against aspirin as first-line therapy. With a more recent year of publication, aspirin was more likely to be recommended (odds ratio 1.72, 95% confidence interval: 1.05 to 2.84) and less likely to be recommended against (odds ratio 0.61, 95% confidence interval: 0.41 to 0.90). No other variables, including the level of evidence used, the composition of the guideline working group, or the objective of the guideline, were associated with the recommendation for or against aspirin.

CONCLUSIONS

Guidelines were inconsistent in their recommendations regarding aspirin as first-line therapy as VTE prophylaxis in arthroplasty patients. Adequately powered randomized controlled trials using modern practices, such as early postoperative mobilization, are needed to better inform clinical practice guidelines.

Low-Dose Enteric-Coated and Chewable Aspirin Are Not Equally Effective in Preventing Venous Thromboembolism in Total Knee and Hip Arthroplasty

BACKGROUND

Low-dose aspirin is an effective venous thromboembolism (VTE) prophylactic medication in primary total joint arthroplasty, but the efficacy and safety of the formulations of chewable and enteric-coated aspirin have not been compared. The purpose of this study was to investigate the VTE and gastrointestinal (GI) complication rates of chewable and enteric-coated 81 mg aspirin bis in die for VTE prophylaxis in primary total joint arthroplasty.

METHODS

A retrospective, single-institution cohort study was performed on patients who underwent primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) from 2017 to 2021. Comparisons were made between 4,844 patients who received chewable, noncoated aspirin 81 mg and 4,388 patients who received enteric-coated 81 mg aspirin. Power analysis demonstrated 1,978 and 3,686 patients were needed per group to achieve a power of 80% for 90-day VTE rates (using inferiority testing) and GI complications (using superiority testing), respectively. Patients had similar baseline characteristics. Statistical analyses were done using t-tests and Chi-squared tests, with statistical significance defined as a P value < .05.

RESULTS

There were no significant differences in the incidences of postoperative VTE (0.31% versus 0.55%; P = .111) or GI complications (0.14% versus 0.14%; P = 1.000) between patients who received either chewable or enteric-coated 81 mg aspirin bis in die in the overall comparison that included both THA and TKA patients combined, or THA patients alone. However, the VTE incidence for TKA patients alone was significantly lower with chewable than enteric-coated aspirin (0.22% versus 0.62%; P = .037), with no difference in GI complications (0.13% versus 0.19%; P = .277).

CONCLUSIONS

Low-dose aspirin in enteric-coated formulation is inferior to chewable aspirin for VTE prophylaxis in primary TKA, but not inferior in THA patients. Both formulations have a similar GI complication rate. Therefore, it is reasonable to consider a transition from enteric-coated to uncoated chewable low-dose aspirin.

Aspirin is an Effective Prophylaxis for Venous Thromboembolism After Revision Hip and Knee Arthroplasty

BACKGROUND

Venous thromboembolism (VTE) following revision total joint arthroplasty (TJA) poses significant risks despite prophylactic measures. The optimal VTE prophylaxis agent for revision TJA remains unclear. This study aimed to compare aspirin against various anticoagulant agents regarding efficacy and safety in preventing symptomatic VTE events after revision TJA.

METHODS

A retrospective analysis included 4,575 patients undergoing revision TJA between 2008 and 2020. Of these, 2,091 received aspirin, while 2,484 received other anticoagulants. Demographic, procedural, and outcome data were collected. Logistic regression models were used to identify predictors of symptomatic VTE.

RESULTS

The aspirin group showed a significantly lower incidence of symptomatic VTE compared to the other anticoagulant group (0.53 versus 2.54%, P < .001). Logistic regression confirmed a higher risk of VTE with other anticoagulants (odds ratio: 0.2 to 0.26, P < .001), while blood transfusion (odds ratio: 2.72, P = .001) were identified as risk factors.

CONCLUSIONS

This study demonstrated that aspirin is a viable and potentially safer option than other anticoagulants, exhibiting comparable efficacy in preventing VTE events in revision TJA. Balancing effectiveness and safety is crucial, considering patient-specific risk factors and bleeding tendencies. This large cohort study demonstrated that aspirin was associated with a more effective and safer VTE prophylaxis agent, compared to other anticoagulants, in patients undergoing revision TJA.

Aspirin prophylaxis is not associated with increased risk of venous thromboembolism in arthroplasty for femoral neck fractures: a non-inferiority study

PURPOSE

Venous thromboembolism (VTE) is a known complication of hip arthroplasty for femoral neck fractures (FNF) with various prophylactic anticoagulants utilized to decrease risk. The purpose of this study was to assess the efficacy and perioperative outcomes associated with aspirin for VTE prophylaxis following arthroplasty for FNF.

METHODS

Medical records of 1,220 patients who underwent hip hemiarthroplasty (HHA) or total hip arthroplasty (THA) at an urban academic center from 2011 to 2022 were retrospectively reviewed. Patient characteristics and perioperative outcomes, including length of stay (LOS), VTE, 90-day hospital encounters, and discharge disposition, were collected. Outcomes for patients prescribed aspirin (n = 214) were compared to those prescribed non-aspirin VTE prophylaxis (n = 1006) using propensity score matching.

RESULTS

Patients who received aspirin had higher rates of THA (36.0 vs 26.7%; p = 0.008). There were no significant risk-adjusted differences in the incidence of VTE (0.5 vs 0.5%, p = 1.000) and 90-day readmissions (10.4 vs 12.3%, p = 0.646) between patients prescribed aspirin and non-aspirin VTE prophylaxis, respectively. Patients prescribed non-aspirin agents had higher rates of non-home discharge (73.9 vs 58.5%; p < 0.001) and longer LOS (143.5 vs 124.9 h; p = 0.005). Sub-analysis of patients prescribed aspirin and non-aspirin prophylaxis based on comorbidity scores demonstrated no difference in VTE incidence for low (0.0 vs 1.6%, p = 1.000) and high scores (0.0 vs 0.0%, p = 1.000), respectively.

CONCLUSION

Aspirin is not associated with increased incidence of VTE after HHA or THA for FNF. Aspirin prophylaxis should be considered in hip fracture patients to mitigate bleeding risk, particularly those with low to intermediate VTE risk.

LEVEL OF EVIDENCE

Level III, Retrospective study.

Comparison of efficacy and safety between aspirin and oral anticoagulants for venous thromboembolism prophylaxis after major orthopaedic surgery: a meta-analysis of randomized clinical trials

Background: venous thromboembolism (VTE) is one of the most common complications after major orthopaedic surgery. Recent studies have suggested that aspirin may also be effective in preventing VTE, but it is still controversial whether it can be routinely used. Objectives: To compare the efficacy and safety of aspirin against oral anticoagulants in the prevention of VTE following total hip arthroplasty (THA), total knee arthroplasty (TKA) or hip fracture surgery (HFS). Methods: Relevant publications have been obtained using electronic search databases such as PubMed, Embase, Web of Science, Cochrane Library, and Clinical Trials. gov. from inception to 20 July 2023. Only RCTs evaluating the efficacy and safety of aspirin compared with oral anticoagulants undergoing major orthopaedic surgery were included in the meta-analysis. The primary outcome reported was any VTE event (including deep vein thrombosis (DVT) and pulmonary embolism (PE)). Secondary outcomes included mortality, major bleeding (including gastrointestinal bleed, cerebrovascular hemorrhage, or any bleeding requiring a return to the theater), minor bleeding (ecchymosis, epistaxis, hematuria), and wound complications. The risk of bias for all included studies was assessed according to the Cochrane Collaboration's tool. Results: After screening 974 studies, 12 randomized clinical trials (RCTs) were included, involving 5,088 participants, including 2,540 participants in aspirin, 2,205 participants in rivaroxaban, and 323 participants in warfarin. Aspirin was found to be less effective than oral anticoagulants in thromboprophylaxis after major orthopedic surgery (RR = 1.206, 95% CI 1.053-1.383). After subgroup analysis according to the type of oral anticoagulant, the results showed that aspirin was similar to rivaroxaban and inferior to warfarin. Considering that the studies in the warfarin group were all conducted before 2000, our results need to be further confirmed. In addition, the aspirin group had a higher risk of VTE than the control group in other subgroups, including a follow-up time of ≤3 months, type of procedure as TKA, high-dose aspirin (≥650 mg qd), and no combined use of mechanical prophylaxis. In terms of safety events, aspirin did not show significant differences in major bleeding (RR = 0.952, 95% CI 0.499-1.815), all-cause mortality (RR = 1.208, 95% CI 0.459-3.177), and wound-related events (RR = 0.618, 95% CI 0.333-1.145) compared with oral anticoagulants, and aspirin was associated with a reduction in the risk of minor bleeding (RR = 0.685, 95% CI 0.552-0.850) events and total bleeding (RR = 0.726, 95% CI 0.590-0.892). Conclusion: Aspirin reduces bleeding risk after major orthopedic surgery compared with oral anticoagulants, but may sacrifice VTE prevention to some extent. Updated evidence is needed to analyze the thromboprophylaxis effects of aspirin in patients undergoing major orthopedic surgery. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=463481, identifier CRD42023463481.

Clinical outcomes of DAA and related techniques in hip arthroplasty

Total hip arthroplasty (THA) has been one of the most successful surgical interventions in recent memory and is nicknamed by some the "Surgery of the Century". Over the past decade, there has been a drastic change in THA management with the rise of the direct anterior approach both globally and in the USA market. While many would remark that this has been driven by false marketing, it is clear that the direct anterior approach can be an effective and safe way to perform a THA.It is the goal of this review to highlight evidence of its outcomes and clinical advantages, in particular, how it can decrease dislocation, even in high-risk individuals, and result in faster recovery in the early postoperative period with decreased muscular inflammation. We will also highlight its major disadvantages, including but not limited to increased wound complications and risk for periprosthetic fracture. Hopefully, this review will provide up-to-date information on the current state of the direct anterior approach and provide recommendations on patients that would be optimal candidates for this technique.

Venous Thromboembolism Prophylaxis in Major Orthopedic Surgeries and Factor XIa Inhibitors

Venous thromboembolism (VTE), comprising pulmonary embolism (PE) and deep vein thrombosis (DVT), poses a significant risk during and after hospitalization, particularly for surgical patients. Among various patient groups, those undergoing major orthopedic surgeries are considered to have a higher susceptibility to PE and DVT. Major lower-extremity orthopedic procedures carry a higher risk of symptomatic VTE compared to most other surgeries, with an estimated incidence of ~4%. The greatest risk period occurs within the first 7-14 days following surgery. Major bleeding is also more prevalent in these surgeries compared to others, with rates estimated between 2% and 4%. For patients undergoing major lower-extremity orthopedic surgery who have a low bleeding risk, it is recommended to use pharmacological thromboprophylaxis with or without mechanical devices. The choice of the initial agent depends on the specific surgery and patient comorbidities. First-line options include low-molecular-weight heparins (LMWHs), direct oral anticoagulants, and aspirin. Second-line options consist of unfractionated heparin (UFH), fondaparinux, and warfarin. For most patients undergoing knee or hip arthroplasty, the initial agents recommended for the early perioperative period are LMWHs (enoxaparin or dalteparin) or direct oral anticoagulants (rivaroxaban or apixaban). In the case of hip fracture surgery, LMWH is recommended as the preferred agent for the entire duration of prophylaxis. However, emerging factor XI(a) inhibitors, as revealed by a recent meta-analysis, have shown a substantial decrease in the occurrence of VTE and bleeding events among patients undergoing major orthopedic surgery. This discovery poses a challenge to the existing paradigm of anticoagulant therapy in this specific patient population and indicates that factor XI(a) inhibitors hold great promise as a potential strategy to be taken into serious consideration.

Comparison of low-dose (162 mg) and high-dose (650 mg) Aspirin prophylaxis following total joint arthroplasty: a prospective cohort study

Since Aspirin's adverse effects are dose-dependent, and evidence supporting the use of low-dose (LD) Aspirin in preventing venous thromboembolism (VTE) after total hip arthroplasty (THA) is weak, the authors do not know what the minimal effective dosage of Aspirin is to prevent VTE. This study aimed to compare the rates of 90-day symptomatic VTE following THA and total knee arthroplasty in healthy patients taking LD Aspirin vs. high-dose (HD) Aspirin for 6 weeks postoperatively.

MATERIALS AND METHODS

A prospective cohort of patients with THA and total knee arthroplasty was conducted at two tertiary centres. Symptomatic VTE within 90 days of index arthroplasty was the primary outcome; gastrointestinal bleeding (GIB) and mortality were secondary outcomes.

RESULTS

The final analysis included 312 consecutive patients: 158 in the LD group and 154 in the HD group. Two groups were similar regarding preoperative data, including sex, age, BMI, smoking, diabetes mellitus, Hgb and platelet count, and type of surgery. The LD group had one deep vein thrombosis (0.6%), and the HD group had two (1.3%) (P=0.62). Neither group had PTE. Therefore, VTE rates are the same as deep vein thrombosis rates and similar between the groups (0.6% vs. 1.3%, P=0.62)Regarding GIB due to anticoagulant therapy, no patient in the LD group reported GIB, whereas two (1.3%) patients in the HD group reported GIB within 90 days of arthroplasty. GIB rates did not differ significantly between groups (P=0.24). Considering VTE + GIB combined, the HD groups showed a higher rate of complications (N=4, 2.6%) than the LD groups (N=1, 0.6%) but not statistically significant (P=0.21).

CONCLUSIONS

Prophylactic administration of Aspirin with low doses (81 mg BID) and high doses (325 mg BID) for six weeks is equally effective at reducing VTE in total joint arthroplasty patients and had similar adverse effects.

LEVEL OF EVIDENCE

Therapeutic Level II.

Thirty day low-dose versus regular-dose aspirin for venous thromboembolism prophylaxis in primary total joint arthroplasty

BACKGROUND

The optimal dosing of aspirin (ASA) monotherapy for prophylaxis after total joint arthroplasty is debatable. The objective of this study was to compare two ASA regimens with regards to symptomatic deep venous thrombosis (DVT), pulmonary embolism (PE), bleeding, and infection 90 days after primary total hip arthroplasty (THA) and total knee arthroplasty (TKA).

METHODS

We retrospectively identified 625 primary THA and TKA surgeries in 483 patients who received ASA for 4 weeks post-op. 301 patients received 325 mg once daily (QD) and 324 patients received 81 mg twice daily (BID). Patients were excluded if they were minors, had a prior venous thromboembolism (VTE), had ASA allergy, or received other VTE prophylaxis drugs.

RESULTS

There was a significant difference in rate of bleeding and suture reactions between the two groups. Bleeding was 7.6% for 325 mg QD and 2.5% for 81 mg BID (p = .0029 Χ2, p = .004 on multivariate logistic regression analysis). Suture reactions were 3.3% for 325 mg QD and 1.2% for 81 mg BID (p = .010 Χ2, p = .027 on multivariate logistic regression analysis). Rates of VTE, symptomatic DVT, and PE were not significantly different. The incidence of VTE was 2.7% for 325 mg QD and 1.5% for 81 mg BID (p = .4056). Symptomatic DVT rates were 1.6% for 325 mg QD and 0.9% for 81 mg BID (p = .4139). Deep infection was 1.0% for 325 mg QD and 0.31% for 81 mg BID (p = .3564).

CONCLUSION

Low-dose ASA in patients with limited comorbidities undergoing primary THA and TKA is associated with significant lower rates of bleeding and suture reactions than high dose ASA. Low-dose ASA was not inferior to higher dose ASA for the prevention of VTE, wound complications, and infection 90 days postoperatively.

Aspirin thromboprophylaxis following primary total knee arthroplasty is associated with a lower rate of early prosthetic joint infection compared with other agents

BACKGROUND

Patients undergoing total knee arthroplasty (TKA) are at increased risk of venous thromboembolism (VTE). Aspirin has been shown to be effective at reducing rates of VTE. In select patients, more potent thromboprophylaxis is indicated, which has been associated with increased rates of bleeding and wound complications. This study aimed to evaluate the effect of thromboprophylaxis choice on rates of early prosthetic joint infection (PJI) following TKA.

METHODS

A review of 11,547 primary TKA patients from 2013 to 2019 at a single academic orthopaedic hospital was conducted. The primary outcome measure was PJI within 90 days of surgery as measured by Musculoskeletal Infection Society criteria. There were 59 (0.5%) patients diagnosed with early PJI. Chi-square and Welch-Two Sample t-tests were used to determine statistically significant relationships between thromboprophylaxis and demographic variables. Significance was set at p<0.05. Multivariate logistic regression adjusted for age, body mass index, sex, and Charlson comorbidity index was performed to identify and control for independent risk factors for early PJI.

RESULTS

There was a statistically significant difference in the rates of early PJI between the aspirin and non-aspirin group (0.3 vs 0.8%, p<0.001). Multivariate logistic regressions revealed that patients given aspirin thromboprophylaxis had significantly lower odds of PJI (odds ratios (OR)=0.51, 95% Confidence Interval (CI) 0.29 to 0.89, p=0.019) compared to non-aspirin patients.

CONCLUSIONS

The use of aspirin thromboprophylaxis following primary TKA is independently associated with a lower rate of early PJIs. Arthroplasty surgeons should consider aspirin as the gold standard thromboprophylaxis in all patients in which it is deemed medically appropriate and should carefully weigh the morbidity of PJI in patients when non-aspirin thromboprophylaxis is considered.

Editorial Commentary: Prophylaxis Against Deep Venous Thrombosis Should Be the Norm After Knee Arthroscopy

Knee arthroscopy has low complication rates overall, and most complications are not overly disabling. Yet one of the most concerning complications is venous thromboembolism, and pulmonary embolism (PE), in particular. The combination of low rate of venous thromboembolism in knee arthroscopy but high potential cost in the event of PE makes for a challenging risk-benefit analysis in the decision for whether to use thromboprophylaxis. Research is inherently difficult due to the infrequency of deep venous thrombosis and PE, leaving orthopaedic surgeons to fill in the gaps with clinical judgement. Risk stratification based on patient risk factors (e.g., oral contraceptives, renal disease, cardiovascular disease) and specific surgical procedure (e.g., meniscectomy, anterior cruciate ligament reconstruction) are important to define the highest-risk patients that may warrant stronger anticoagulation. Yet even in low-risk patients, given the potential severity of a PE and safety of aspirin, surgeons should consider aspirin as thromboprophylaxis.

Aspirin May Be a Suitable Prophylaxis for Patients with a History of Venous Thromboembolism Undergoing Total Joint Arthroplasty

BACKGROUND

In recent years, aspirin has become a popular agent for venous thromboembolism (VTE) prophylaxis following total joint arthroplasty (TJA). Yet patients with a history of VTE are often given more aggressive prophylactic agents because of their increased baseline risk. The purpose of this study was to assess whether aspirin is an effective prophylactic agent in patients with a history of VTE.

METHODS

This was a single-institution, retrospective cohort study. The electronic clinical records of 36,333 patients undergoing TJA between 2008 and 2020 were reviewed. Data on demographic characteristics, comorbidities, intraoperative factors, and postoperative complications were collected. A propensity score-matched analysis was performed, as well as a multivariate regression analysis to account for confounders.

RESULTS

Of the 36,333 patients undergoing TJA, 1,087 patients (3.0%) had a history of VTE and were not receiving chronic non-aspirin. The risk for subsequent VTE was significantly higher (p = 0.03) in patients with a history of VTE (1.4%) compared with patients without prior VTE (0.9%). However, the incidence of VTE was not significantly lower (p = 0.208) in patients with a history of VTE who received aspirin (0.4%) compared with patients who received other VTE prophylaxis (1.5%). Propensity score matching showed no difference in VTE rates between the 2 groups (2.2% compared with 0.55%; p = 0.372). In a regression analysis accounting for VTE risk, the administration of aspirin was not associated with an increased risk for subsequent VTE (adjusted odds ratio, 0.32 [95% confidence interval, 0.02 to 1.66]; p = 0.274).

CONCLUSIONS

Our findings suggest that, although patients with a history of VTE have an increased baseline risk for subsequent VTE, aspirin may be a suitable VTE prophylaxis in this group of patients.

LEVEL OF EVIDENCE

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

Improving Postoperative Acute Kidney Injury Rates Following Primary Total Joint Arthroplasty

BACKGROUND

Perioperative hip and knee arthroplasty complications remain a significant clinical and financial burden. Our institution has shifted to developing protocols to decrease these perioperative complications. This study focuses on acute kidney injury (AKI) rate status post primary total joint arthroplasty (TJA). Current literature demonstrates a 2%-15% incidence of AKI following TJA. However, there is a paucity of published literature on protocols that have effectively reduced AKI rates following TJA. The purpose of this study is to evaluate the effect that our institutionally developed perioperative renal protocol had on the postoperative AKI rates.

METHODS

A retrospective cohort study was performed. Patient demographics, baseline creatinine, and postoperative creatinine values during the patient's hospitalization were collected and analyzed. The preintervention cohort data contained all patients at our institution who underwent a primary TJA from November 1, 2016 to January 1, 2018. The postintervention cohort included all primary TJA patients from July 1, 2018 to February 2, 2020. AKI was defined using the AKI Network classification system comparing baseline and postoperative creatinine values. A multivariate analysis was performed to determine the statistical significance of our results.

RESULTS

Before intervention 1013 patients underwent a primary TJA with 68 patients developing an AKI postoperatively. After intervention 2169 patients underwent primary TJA with 90 patients developing an AKI (6.71% vs 4.15%; P = .0015, odds ratio = 0.59, 95% confidence interval = 0.42-0.82).

CONCLUSION

This study demonstrated that implementation of a perioperative renal protocol can significantly reduce AKI rates. A reduction in AKI rates following TJA will result in improved outcomes and secondarily decrease the financial impact of postoperative complications seen following TJA.

Is aspirin still relevant as a single pharmacological agent for venous thromboembolism prophylaxis post hip and knee arthroplasty surgery: A retrospective review

Introduction: Aspirin is widely used for the prevention of venous thromboembolism (VTE) after total hip arthroplasty (THA) and total knee arthroplasty (TKA). It is well-established that the bleeding and wound complication risk for aspirin is low or equivalent to the other anticoagulant agents, but there is still ongoing controversy regarding the efficacy of aspirin for VTE prophylaxis. The current HSE (2012) guideline suggests 72 h of enoxaparin and 4 weeks of Aspirin therapy. But is this practice still relevant with more recent guidelines, NICE (2021) and SIGN (2014) suggesting that Aspirin is not recommended as a single pharmacological agent for VTE prophylaxis. Method: A Retrospective review was performed of a single centre, between January 2016 and May 2021 assessing for symptomatic VTE post-THA and TKA. All the patients received enoxaparin and aspirin as per the HSE guidelines. Using NIMIS we assessed which patients received a workup for potential symptomatic VTE and who had a confirmed VTE within 3 months post-surgery. The secondary outcome was mortality within 3 months post-surgery. Results: A total of 1178 patients (721 undergoing THR and 457 undergoing TKR) were included in the study. The number of patients who received a workup for potential symptomatic VTE was 124 of 1178 (10.53%). VTE occurred in 13 of 721 patients (1.80%) of the THR patients and 1 of 457 (0.22%) of the TKR patients, and a total of 14 of 1178 patients (1.19%). Of these 7 (0.59%) patients developed a DVT and 7 (0.59%) a PE. No patients suffered a fatal pulmonary embolism within 90 days of index surgery nor any other cause of mortality. Conclusion: Aspirin is not only still relevant but can be considered as one of the most optimal pharmacological agents in preventing VTE after THA and TKA.

Time to Venous Thromboembolism Events Following Total Hip Arthroplasty: A Comparison Between Aspirin and Warfarin

BACKGROUND

The attitude and approach of orthopedic community for minimizing venous thromboembolism (VTE) has evolved over the last decade with the trend toward use of aspirin (and mechanical modalities) in lieu of aggressive anticoagulation. The optimal length of VTE prophylaxis following total hip arthroplasty (THA) still remains unknown. This study aimed to determine the timing of VTE in patients who received aspirin compared to warfarin, and determine if 30 days of prophylaxis remain adequate.

METHODS

This is a retrospective study of 18,003 patients undergoing primary and revision THA at a single institution between January 2008 and August 2020. During this time, our institution underwent a transition from the use of warfarin to aspirin as the main method for VTE prophylaxis. Symptomatic deep vein thrombosis and pulmonary embolism occurring within 90 days of surgery were identified from medical records and phone call logs. Aspirin and warfarin cohorts were matched to account for demographic and comorbidity differences. Timing of pulmonary embolism was determined based on either the date of diagnostic imaging or patient-provider phone calls confirming diagnosis.

RESULTS

The cohorts included 46 patients in the warfarin group and 46 in the aspirin group. Time to VTE was significantly shorter in the warfarin group compared to aspirin (P = .021) with a median time to VTE of 3 days (interquartile range 2-14) and 10 days (interquartile range 4-19) respectively. Over 90% of the events occurred within 32 or 30 days of surgery in the warfarin and aspirin groups respectively.

CONCLUSION

Based on the findings, a 30-day aspirin prophylaxis remains appropriate for patients undergoing THA.

Prophylaxis for Venous Thromboembolic Events in Elective Total Hip and Total Knee Arthroplasty

Venous thromboembolism (VTE) is a serious complication after major orthopaedic operations, such as a total hip (THA) and knee (TKA) arthroplasty. Therefore, perioperative VTE prophylaxis is recommended; a multitude of modern options are available, including both pharmacologic (aspirin, unfractionated and lowmolecular-weight heparin, vitamin K antagonists, and novel oral anticoagulants) and/or mechanical interventions (early mobilization, graduated compression stockings, intermittent pneumatic compression devices, and venous foot pumps). However, because of the abundance of these possibilities, it is crucial to understand the benefits and drawbacks of each VTE prophylaxis option to ensure that the optimal treatment plan is developed for each patient. The American College of Chest Physicians (AACP) and the American Academy of Orthopaedic Surgeons (AAOS) have both published individual guidelines on VTE prophylaxis regimens, alongside numerous studies evaluating the efficacy and outcomes of the different prophylaxis modalities. The purpose of this review is to provide a summary of the evidence on VTE prophylaxis after elective total hip and knee arthroplasty based on current guidelines and highlight the major concerns and potential complications.

Weight-Based Aspirin Dosing May Further Reduce the Incidence of Venous Thromboembolism Following Primary Total Joint Arthroplasty

BACKGROUND

Obesity poses a challenge to thromboembolic prophylaxis following total joint arthroplasty (TJA). The purpose of this study is to evaluate a weight-based aspirin dosing regimen for prevention of venous thromboembolism (VTE) following TJA.

METHODS

This is a retrospective observational study of 2403 patients who underwent primary total hip or knee arthroplasty at one institution. A weight-based aspirin dosing regimen for VTE prophylaxis was administered to 1247 patients: patients weighing ≥120 kg received 325 mg aspirin twice daily (BID) and those weighing <120 kg received 81 mg aspirin BID for 4 weeks. In total, 1156 patients in the comparison cohort received 81 mg aspirin BID. VTE and gastrointestinal bleeding events were identified through chart review at 42 days and 6 months postoperatively. A multivariable logistic regression was performed to adjust for covariates.

RESULTS

The weight-based aspirin cohort had a significantly lesser incidence of VTE at 42 days (P = .03, relative risk [RR] 0.31, 95% confidence interval 0.12-0.82) and 6 months (P = .03, RR 0.38, 95% confidence interval 0.18-0.80). There was no difference in VTE incidence between total hip arthroplasty and total knee arthroplasty cases (P = .8). There was no difference in gastrointestinal bleeding events between the cohorts at 42 days (P = .69) or 6 months (P = .92). Subanalysis of patients weighing ≥120 kg demonstrated a significant difference between the cohorts with a VTE incidence of 3.48% and 0% in the 81 mg and weight-based cohorts, respectively (P = .02).

CONCLUSION

Patients prescribed a weight-based aspirin regimen had significantly fewer VTEs after TJA compared to historical controls with an RR reduction of 69% at 6 weeks and 62% at 6 months postoperatively. This suggests the need to factor patient weight when determining postoperative VTE prophylaxis with aspirin.

Prevention of venous thromboembolism with aspirin following knee surgery: A systematic review and meta-analysis

Venous thromboembolism (VTE) is a well-known complication following orthopaedic surgery. The incidence of this complication has decreased substantially since the introduction of routine thromboprophylaxis. However, concerns have been raised about increased bleeding complications caused by aggressive thromboprophylaxis.Attention has grown for aspirin as a safer thromboprophylactic agent following orthopaedic surgery.A systematic review using MEDLINE, Embase and Web of Science databases was undertaken to compare the effectiveness of aspirin prophylaxis following knee surgery with the current standard prophylactic agents (low molecular weight heparin [LMWH], vitamin K antagonists and factor Xa inhibitors).No significant difference in effectiveness of VTE prevention was found between aspirin, LMWH and warfarin. Factor Xa inhibitors were more effective, but increased bleeding complications were reported.As evidence is limited and of low quality with substantial heterogeneity, further research with high-quality, adequately powered trials is needed. Cite this article: EFORT Open Rev 2021;6:892-904. DOI: 10.1302/2058-5241.6.200120.

Incidence, Outcomes and Risk Factors of Heparin-Induced Thrombocytopenia After Total Joint Arthroplasty: A National Inpatient Sample Database Study

Backgrounds: Heparin-induced thrombocytopenia (HIT) is a severe immune-mediated complication of heparin exposure, leading to negative consequences after total hip (THA) and knee arthroplasty (TKA). Materials and Methods: A retrospective study was conducted using the National Inpatient Sample (NIS) database from 2005 to 2014. The incidence and outcomes of HIT after THA or TKA were documented. Logistic regression analysis was performed to identify the postoperative HIT risk factors. Results: A total of 59 3045 patients who underwent THA and 1228 707 patients who underwent TKA were identified. The cumulative incidences were 0.02% and 0.01%, respectively. The HIT group presented significantly higher Charlson Comorbidity Index and Elixhauser Comorbidity Index scores, longer hospital stays (LOS), and higher medical costs. HIT led to a significantly higher mortality rate after THA (2.17% vs 0.16%, P = .0091). In THA, the HIT risk factors were racial minority, AIDS, pulmonary circulation disorders (PCD), psychoses, and hypertension. In TKA, the HIT risk factors were racial minority, PCD, and weight loss. Conclusion: The incidence of HIT after THA and TKA is relatively low; however, HIT significantly increases inpatient mortality, LOS, and medical cost.

Thirty Days of Aspirin for Venous Thromboembolism Prophylaxis Is Adequate Following Total Knee Arthroplasty, Regardless of the Dose Used

BACKGROUND

The optimal length of aspirin prophylaxis to minimize venous thromboembolism (VTE) following total knee arthroplasty (TKA) remains unknown. This study aimed to determine the timing of VTE after TKA in patients who received low and high dose aspirin, and determine if 30 days of prophylaxis remains adequate.

METHODS

We retrospectively reviewed records of 9208 patients undergoing primary TKA between 2010 and 2020 who received either low (81 mg twice daily, n = 4413) or high (325 mg twice daily, n = 4795) dose aspirin for VTE prophylaxis. Symptomatic VTEs occurring within 90 days of surgery were identified from medical records and phone call logs. Major bleeding events (MBE) within the first 30 days were also documented. Time to event was recorded.

RESULTS

Overall, 88 patients (1.0%) developed symptomatic VTE, with no significant differences in incidence between the low (n = 40, 0.9%) and high (n = 48, 1.0%) dose groups (P = .669). The median time to VTE was 8 days (interquartile range [IQR] 2-15.5), median time to deep vein thrombosis was 12 days (IQR 5-18), and median time to pulmonary embolism was 5 days (IQR 1.5-15). There was a similar distribution in time to VTE in both the low and high dose groups. Aside from a single DVT occurring at day 44, all VTE occurred within 30 days of surgery. During the prophylactic time period, 41 patients (0.4%) developed MBE, which tended to occur more frequently (0.6% vs 0.3%, P = .018) and earlier in the high dose group.

CONCLUSION

Based on the findings, a 30-day low or high dose aspirin regimen remains optimal for prevention of VTE without increasing MBE in TKA patients.

Venous Thromboembolic Prophylaxis After Total Hip and Knee Arthroplasty

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The selection of an agent for prophylaxis against venous thromboembolism (VTE) is a balance between efficacy and safety. The goal is to prevent symptomatic VTE while limiting the risk of bleeding.

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The optimal agent for VTE prophylaxis has not been identified. The American College of Chest Physicians guidelines recommend that, after total hip or total knee arthroplasty, patients receive at least 10 to 14 days of 1 of the following prophylaxis agents: aspirin, adjusted-dose vitamin K antagonist, apixaban, dabigatran, fondaparinux, low-molecular-weight heparin, low-dose unfractionated heparin, rivaroxaban, or portable home mechanical compression.

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The use of aspirin for VTE prophylaxis has increased in popularity over the past decade because it is effective, and it is an oral agent that does not require monitoring. The true efficacy of aspirin needs to be determined in multicenter randomized clinical trials.

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Validated risk stratification protocols are essential to identify the safest and most effective regimen for VTE prophylaxis for individual patients. There is no consensus regarding the optimal method for risk stratification; the selection of a prophylaxis agent should be determined by shared decision-making with the patient to balance the risk of thrombosis versus bleeding.

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Patients with atrial fibrillation being treated with chronic warfarin therapy or direct oral anticoagulants should stop the agent 3 to 5 days prior to surgery. Patients do not typically require bridging therapy prior to surgery.

Time for an Update? A Look at Current Guidelines for Venous Thromboembolism Prophylaxis After Hip and Knee Arthroplasty and Hip Fracture

Venous thromboembolism is a well-established complication of total hip and knee arthroplasty and hip fracture surgery. Clinical practice guidelines have been proposed to help clinicians provide prophylaxis against this risk. However, most guidelines reference data that are becoming outdated because of new advances in perioperative protocols. Recent data would suggest that aspirin may be appropriate for most patients after total hip and knee replacement and a more potent chemoprophylaxis for higher risk patients. Low-molecular-weight heparin remains the recommended choice after hip fracture surgery, although there is a paucity of recent literature in this patient population. There are randomized trials currently underway in the arthroplasty population that may guide clinicians in the appropriate choice of chemoprophylaxis. These studies should inform updates to the current clinical practice guidelines.

Direct anterior approach for total hip arthroplasty using the "bikini incision"

OBJECTIVE

The classic skin incision for direct anterior approach (DAA) total hip arthroplasty (THA) is usually placed over the belly of the tensor fasciae latae (TFL) muscle parallel to the axis of the lower extremity. In the "bikini incision" technique however, a more horizontal skin incision is used and placed parallel to the skin creases, which largely corresponds to the skin's tension lines to prevent hypertrophic scarring and optimize cosmetic outcomes.

INDICATIONS

Primary or secondary osteoarthritis, femoral neck fracture, aseptic acetabular component loosening with sufficient bone stock and without the need for proximal extension of the approach, head and/or liner exchange.

CONTRAINDICATIONS

Complex primary or revision THA requiring extensile distal and/or acetabular exposure, revision with pre-existing longitudinal DAA incision, inguinal skin infection.

SURGICAL TECHNIQUE

The skin incision, located three fingerbreadths distal to the anterior superior iliac spine (ASIS), is orientated parallel to the groin crease. One third of the incision is medial and two thirds lateral to the ASIS. Subcutaneous dissection should only be performed in the lateral two thirds of the incision to protect the main branches of the lateral femoral cutaneous nerve (LFCN). The fascia lata is opened as far lateral over the muscle belly as possible to leave the LFCN untouched within its fascial sheet. The stepwise procedure consists of three key steps: capsular exposure, capsular release, and component insertion. The approach allows for an excellent 360° exposure of the acetabulum. The femur is aligned along the incision during femoral elevation and adduction. With this technique, DAA hip arthroplasty can be performed in a less-invasive way providing best possible functional and cosmetic outcomes.

POSTOPERATIVE MANAGEMENT

No restrictions in ambulation or range of motion. Deep vein thrombosis prophylaxis.

RESULTS

In a prospective series of 532 consecutive patients undergoing 613 primary THA with a bikini-incision in 2017, a good clinical outcome with a 2.3% incidence of wound-related problems was observed. In particular, obese patients can also benefit from the technique.

Low-Dose vs Regular-Dose Aspirin for Venous Thromboembolism Prophylaxis in Primary Total Joint Arthroplasty

BACKGROUND

Consensus on whether low-dose (81 mg) or regular-dose (325 mg) aspirin (ASA) is more effective for venous thromboembolism (VTE) chemoprophylaxis in primary total joint arthroplasties (TJAs) is not reached. The goal of this study is to evaluate the efficacy of low-dose and regular-dose ASA for VTE chemoprophylaxis in primary total hip arthroplasties and total knee arthroplasties.

METHODS

We retrospectively identified 3512 primary TJAs (2344 total hip arthroplasties and 1168 total knee arthroplasties) with ASA used as VTE chemoprophylaxis between 2000 and 2019. Patients received ASA twice daily for 4-6 weeks after surgery with 961 (27%) receiving low-dose ASA and 2551 (73%) receiving regular-dose ASA. The primary endpoint was 90-day incidence of symptomatic VTEs. Secondary outcomes were gastrointestinal (GI) bleeding events and mortality. The mean age at index TJA was 66 years, 54% were female, and mean body mass index was 31 kg/m². The mean Charlson Comorbidity Index was 3.5. Mean follow-up was 3 years.

RESULTS

There was no difference in 90-day incidence of symptomatic VTEs between low-dose and regular-dose ASA (0% vs 0.1%, respectively; P = .79). There were no GI bleeding events in either group. There was no difference in 90-day mortality between low-dose and regular-dose ASA (0.3% vs 0.1%, respectively; P = .24).

CONCLUSION

In 3512 primary TJA patients treated with ASA, we found a cumulative incidence of VTE <1% at 90 days. Although this study is underpowered, it appears that twice daily low-dose ASA was equally effective to twice daily regular-dose ASA for VTE chemoprophylaxis, with no difference in risk of GI bleeds or mortality.

LEVEL OF EVIDENCE

III, retrospective cohort study.

The Influence of UV Light on Photodegradation of Acetylsalicylic Acid

Photodegradation of the aqueous solutions of acetylsalicylic acid, in the absence (ASA) and the presence of excipients (ASE), is demonstrated by the photoluminescence (PL). A shift of the PL bands from 342 and 338 nm to 358 and 361-397 nm for ASA and ASE in solid state and as aqueous solutions was reported. By exposure of the solution of ASA 0.3 M to UV light, a decrease in the PL band intensity was highlighted. This behavior was revealed for ASA in the presence of phosphate buffer (PB) having the pH equal to 6.4, 7, and 8 or by the interaction with NaOH 0.3 M. A different behavior was reported in the case of ASE. In the presence of PB, an increase in the intensity of the PL band of ASE simultaneously with a change of the ratio between the intensities of the bands at 361-364 and 394-397 nm was highlighted. The differences between PL spectra of ASA and ASE have their origin in the presence of salicylic acid (SAL). The interaction of ASE with NaOH induces a shift of the PL band at 405-407 nm. Arguments for the reaction of ASA with NaOH are shown by Raman scattering and FTIR spectroscopy.

Nanocomposites for Enhanced Osseointegration of Dental and Orthopedic Implants Revisited: Surface Functionalization by Carbon Nanomaterial Coatings

Over the past few decades, carbon nanomaterials, including carbon nanofibers, nanocrystalline diamonds, fullerenes, carbon nanotubes, carbon nanodots, and graphene and its derivatives, have gained the attention of bioengineers and medical researchers as they possess extraordinary physicochemical, mechanical, thermal, and electrical properties. Recently, surface functionalization with carbon nanomaterials in dental and orthopedic implants has emerged as a novel strategy for reinforcement and as a bioactive cue due to their potential for osseointegration. Numerous developments in fabrication and biological studies of carbon nanostructures have provided various novel opportunities to expand their application to hard tissue regeneration and restoration. In this minireview, the recent research trends in surface functionalization of orthopedic and dental implants with coating carbon nanomaterials are summarized. In addition, some seminal methodologies for physicomechanical and electrochemical coatings are discussed. In conclusion, it is shown that further development of surface functionalization with carbon nanomaterials may provide innovative results with clinical potential for improved osseointegration after implantation.

The incidence of venous thromboembolism in total joint replacement during COVID-19 pandemic: has lockdown had an influence?

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.

Does aspirin prevent venous thromboembolism?

Venous thromboembolism (VTE; deep vein thrombosis and/or pulmonary embolism) is a well-established cause of morbidity and mortality in the medical and surgical patient populations. Clinical research in the prevention and treatment of VTE has been a dynamic field of study, with investigations into various treatment modalities ranging from mechanical prophylaxis to the direct oral anticoagulants. Aspirin has long been an inexpensive cornerstone of arterial vascular disease therapy, but its role in the primary or secondary prophylaxis of VTE has been debated. Risk-benefit tradeoffs between aspirin and anticoagulants have changed, in part due to advances in surgical technique and postoperative care, and in part due to the development of safe, easy-to-use oral anticoagulants. We review the proposed mechanisms in which aspirin may act on venous thrombosis, the evidence for aspirin use in the primary and secondary prophylaxis of VTE, and the risk of bleeding with aspirin as compared with anticoagulation.

Aspirin alleviates denervation-induced muscle atrophy via regulating the Sirt1/PGC-1α axis and STAT3 signaling

Background

Our prior studies have shown that inflammation may play an important triggering role during the process of denervated muscle atrophy. The nonsteroidal anti-inflammatory drug aspirin exhibits the effect of anti-inflammatory factors. This study will investigate the protective effect of aspirin on denervated muscle atrophy and the underlying mechanism.

Methods

Mouse models of denervated muscle atrophy were established. The protective effect of aspirin (20 mg/kg/d, i.p.) on denervated muscle atrophy was analyzed using the wet weight ratio of tibialis anterior (TA) muscle and muscle fiber cross-sectional area (CSA). The levels of inflammatory factors were detected using quantitative reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay. Sirtuins1 (SIRT1)/Peroxisome Proliferator-Activated Receptor γ Co-Activator 1α (PGC-1α) and Signal transducer and activator of transcription 3 (STAT3) signaling pathway and the muscle fiber type related proteins in TA muscle after denervation were analyzed by western blot assay.

Results

Intraperitoneal injection of aspirin (20 mg/kg/d) effectively alleviated denervation-induced muscle atrophy. This mainly manifested as follows: The wet weight ratio of TA muscle and muscle fiber CSA of mice treated with aspirin were significantly greater compared with mice treated with normal saline. The level of myosin heavy chain (MHC) increased, and the levels of muscle specific E3 ubiquitin ligase Muscle-specific RING finger-1 (MuRF-1) and muscle atrophy F-box (MAFbx) were decreased. Mitochondrial vacuolation and autophagy were inhibited, as evidenced by reduced level of autophagy related proteins PINK1, BNIP3, LC3B and Atg7 in mice treated with aspirin compared with mice treated with saline. In addition, aspirin treatment inhibited the slow-to-fast twitch muscle fiber conversion, which were related with triggering the expression of Sirt1 and PGC-1α. Moreover, aspirin reduced the levels of inflammatory factors interleukin-6, interleukin-1β and tumor necrosis factor-α and decreased the activation of STAT3 signaling pathway.

Conclusions

This is the first study to find that aspirin can alleviate denervation-induced muscle atrophy and inhibit the type I-to-type II muscle fiber conversion and mitophagy possibly through regulating the STAT3 inflammatory signaling pathway and Sirt1/PGC-1α signal axis. This study expands our knowledge regarding the pharmacological function of aspirin and provides a novel strategy for prevention and treatment of denervated muscle atrophy.

First Reported Series of Outpatient Total Knee Arthroplasty in the Middle East

Background

Outpatient total knee arthroplasty (TKA) is becoming more commonplace in the United States. Alternatively, the current practice in the Middle East involves an inpatient stay of 7-10 days in the hospital after TKA. This study reports the early results of the first reported series of outpatient TKA performed on patients in the Middle East and compares the clinical and functional outcomes with those of patients who underwent inpatient TKA.

Methods

Eighty-eight patients underwent TKA (inpatient: 44 and outpatient: 44) using the modified intervastus approach in 2 hospitals in the Middle East from 2017 to 2019. Clinical and functional outcomes were assessed by recording the Knee Injury and Osteoarthritis Outcome Score, visual analog scale (VAS) for pain, and knee range of motion (ROM) preoperatively, on the day of surgery, and postoperatively at 2 weeks, 6 weeks, 3 months, and 6 months.

Results

Two patients undergoing outpatient TKA had complications: one patient suffered a periprosthetic fracture on postoperative day 10 after a fall, and the other patient had drainage on postoperative day 5. No complications occurred in the inpatient TKA cohort. There were no significant differences observed in the VAS scores or knee ROM numbers recorded for inpatient and outpatient TKA groups at any of the follow-up periods. Overall, the Knee Injury and Osteoarthritis Outcome Score, VAS, and ROM significantly improved 6 months after surgery compared with preoperative values for both inpatient and outpatient TKA groups.

Conclusions

Outpatient TKA was safely implemented when compared with inpatient TKA, with satisfactory results. A total of 2 complications were seen in this study, which we believe are unrelated to the patient’s discharge status. The concept of outpatient TKA using the modified intervastus approach was very well accepted by the patients in this study and can potentially be applied safely elsewhere in the region.

An Update on Venous Thromboembolism Rates and Prophylaxis in Hip and Knee Arthroplasty in 2020

Patients undergoing total hip and knee arthroplasty are at high risk for venous thromboembolism (VTE) with an incidence of approximately 0.6-1.5%. Given the high volume of these operations, with approximately one million performed annually in the U.S., the rate of VTE represents a large absolute number of patients. The rate of VTE after total hip arthroplasty has been stable over the past decade, although there has been a slight reduction in the rate of deep venous thrombosis (DVT), but not pulmonary embolism (PE), after total knee arthroplasty. Over this time, there has been significant research into the optimal choice of pharmacologic VTE prophylaxis for individual patients, with the objective to reduce the rate of VTE while minimizing adverse side effects such as bleeding. Recently, aspirin has emerged as a promising prophylactic agent for patients undergoing arthroplasty due to its similar efficacy and good safety profile compared to other pharmacologic agents. However, there is no evidence to date that clearly demonstrates the superiority of any given prophylactic agent. Therefore, this review discusses (1) the current prevalence and trends in VTE after total hip and knee arthroplasty and (2) provides an update on pharmacologic VTE prophylaxis in regard to aspirin usage.

Lessons Learned: Using the Caprini Risk Assessment Model to Provide Safe and Efficacious Thromboprophylaxis Following Hip and Knee Arthroplasty

Two of the more common potential complications after arthroplasty are venous thromboembolism (VTE), which includes deep vein thrombosis (DVT) and pulmonary embolus (PE), and excess bleeding. Appropriate chemoprophylaxis choices are essential to prevent some of these adverse events and from exacerbating others. Risk stratification to prescribe safe and effective medications in the prevention of postoperative VTE has shown benefit in this regard. The Department of Orthopaedic Surgery at Syosset Hospital/Northwell Health, which performs over 1200 arthroplasties annually, has validated and is using the 2013 version of the Caprini Risk Assessment Model (RAM) to stratify each patient for risk of postoperative VTE. This tool results in a culling of information, past and present, personal and familial, that provides a truly thorough evaluation of the patient's risk for postoperative VTE. The Caprini score then guides the medication choices for thromboprophylaxis. The Caprini score is only valuable if the data is properly collected, and we have learned numerous lessons after applying it for 18 months. Risk stratification requires practice and experience to achieve expertise in perioperative patient evaluation. Having access to pertinent patient information, while gaining proficiency in completing the Caprini RAM, is vital to its efficacy. Ongoing, real time analyses of patient outcomes, with subsequent change in process, is key to improving patient care.