Deep vein thrombosis after elective knee surgery. An incidence study in 312 patients

Efficacy and safety of commonly used thromboprophylaxis agents following hip and knee arthroplasty

Aims

We investigated the efficacy and safety profile of commonly used venous thromboembolism (VTE) prophylaxis agents following hip and knee arthroplasty.

Methods

A systematic search of PubMed, Embase, Cochrane Library, Web of Science, and OrthoSearch was performed. Prophylaxis agents investigated were aspirin (< 325 mg and ≥ 325 mg daily), enoxaparin, dalteparin, fondaparinux, unfractionated heparin, warfarin, rivaroxaban, apixaban, and dabigatran. The primary efficacy outcome of interest was the risk of VTE, whereas the primary safety outcomes of interest were the risk of major bleeding events (MBE) and wound complications (WC). VTE was defined as the confirmed diagnosis of any deep vein thrombosis and/or pulmonary embolism. Network meta-analysis combining direct and indirect evidence was performed. Cluster rank analysis using the surface under cumulative ranking (SUCRA) was applied to compare each intervention group, weighing safety and efficacy outcomes.

Results

Of 86 studies eligible studies, cluster rank analysis showed that aspirin < 325 mg daily (SUCRA-VTE 89.3%; SUCRA-MBE 75.3%; SUCRA-WC 71.1%), enoxaparin (SUCRA-VTE 55.7%; SUCRA-MBE 49.8%; SUCRA-WC 45.2%), and dabigatran (SUCRA-VTE 44.9%; SUCRA-MBE 52.0%; SUCRA-WC 41.9%) have an overall satisfactory efficacy and safety profile.

Conclusion

We recommend the use of either aspirin < 325 mg daily, enoxaparin, or dabigatran for VTE prophylaxis following hip and knee arthroplasty.

An analysis of risk factors for venous thromboembolism in primary versus revision total joint arthroplasty

Background

One of the most serious complications after primary or revision lower extremity total joint arthroplasty (TJA) is venous thromboembolism disease (VTE). Identifying patients at high risk for VTE allows tailoring of prophylactic anticoagulation regimens to those most vulnerable. This study aimed to identify risk factors for VTE in primary and revision lower extremity TJA.

Methods

The Electronic Medical Record was queried from a single academic institution for all patients who underwent a lower extremity TJA between 2007 and 2020. Demographics, comorbid conditions, perioperative characteristics, and postoperative complications were identified. An Elastic Net Multiple Logistic Regression Model was used to assess 49 covariates and predict those associated with a significant risk of VTE.

Results

We identified 4900 primary and revision total knee arthroplasty (TKA) and total hip arthroplasty (THA) patients. There was no significant difference between primary and revision THA. Primary TKA had a higher rate of VTE than revision TKA. Significant risk factors identified for VTE in THA patients include histories of deep vein thrombosis (DVT), pulmonary embolism (PE), metastatic tumors, hemiplegia, and Hispanic ethnicity. Risk factors for VTE in TKA patients include histories of DVT, PE, metastatic tumors, and postoperative warfarin and heparin use. In all patients, age was a significant predictor of VTE risk.

Conclusion

Our work identifies many risk factors for VTE following TJA. While the increased rate of VTE in some populations may represent selection bias, it also highlights the incomplete understanding of the etiology and prevention of this complication in the joint arthroplasty population and requires further study.

The rate of venous thromboembolism after knee bone marrow concentrate procedures: should we anticoagulate?

PURPOSE

Intra-articular injections of autologous, minimally manipulated, cell therapies such as bone marrow concentrate (BMC) to treat knee osteoarthritis (OA) may delay or prevent future total knee arthroplasty (TKA). Arthroplasty has the known and substantial risk of venous thromboembolism (VTE) and requires routine prophylaxis, whereas the VTE risk associated with knee BMC injections is unknown. We report on the rate of VTE from a large orthobiologics patient registry and assess whether knee BMC procedures require routine prophylaxis.

METHODS

A retrospective analysis of knee osteoarthritis cases tracked in a treatment registry and treated at 72 clinical sites with BMC from 2007 to 2020 who were not prophylactically anticoagulated was performed to identify adverse events (AEs) associated with VTE. Treating physicians were contacted to improve discovery of possible occurrences of VTE.

RESULTS

Twenty cases (0.16%) of VTE were identified from the registry of 12,780 knee BMC treatments. These events were less frequent than the published data demonstrate for anticoagulated TKA patients.

CONCLUSION

Based on the rates of VTE from our retrospective treatment registry analysis compared to the risk of medication-induced haemorrhage, routine prophylactic anticoagulation is not recommended for intra-articular knee BMC procedures. Further research into safety and efficacy of BMC treatment for knee OA is warranted.

CLINICAL TRIAL IDENTIFIER

NCT03011398, retrospectively registered.

Thromboprophylaxis after knee arthroscopy does not decrease the risk of deep vein thrombosis: a network meta-analysis

PURPOSE

The primary aim of this network meta-analysis (NMA) is to compare the incidence of venous thromboembolisms (VTE) and bleeding risk following the use of pharmacological and non-pharmacological thromboprophylaxis for arthroscopic knee surgery (AKS). This study assumed the null hypothesis which was that there will be no difference in the incidence of VTE and bleeding risk when comparing no treatment, pharmacological treatment, and non-pharmacological treatment for preventing VTE events following AKS.

METHODS

A systematic electronic search of CENTRAL, Medline, Embase, and ClinicalTrials.gov was carried out. All English language prospective randomized clinical trials published from date of database inception to November 21, 2021 were eligible for inclusion. All papers addressing arthroscopic knee surgery were eligible for inclusion regardless of timing of surgery, operation, surgical technique, or rehabilitation. Multiple random effects NMAs were conducted to compare all treatments for each outcome. The primary outcome was the incidence of pulmonary embolism (PE) and secondary outcomes consisted of overall deep vein thrombosis (DVT), symptomatic DVT, asymptomatic DVT, and all-cause mortality. Adverse outcomes consisted of major and minor bleeding, as well as adverse events.

RESULTS

A total of nine studies with 4526 patients were included for analysis. There were 1054 patients in the no treatment/placebo group (NT/Placebo), 1646 patients in the graduated compression stockings, 810 patients in the extended-duration (> 10 days) low molecular weight heparin (Ext-LMWH) group, 650 patients in the short-duration (< 10 days) LMWH group (Short-LMWH), and 356 patients in the rivaroxaban group. GCS, Ext-LMWH, Short-LMWH and rivaroxaban all demonstrated low risks of PE, symptomatic DVT, asymptomatic DVT, combined DVT and all-cause mortality. Similarly, all interventions demonstrated a low risk of major bleeding.

CONCLUSION

There is no significant difference in the risk reduction of PEs, symptomatic DVTs, major/minor bleeding, and/or all-cause mortality when using LWMH (including short or extended regimens), rivaroxaban, graduated compression stockings or no treatment following arthroscopic knee surgery. Future primary research on the efficacy of thromboprophylaxis following arthroscopic knee surgery should stratify outcomes based on key patient (i.e., age, sex, comorbidities) and surgical (i.e., major vs. minor surgery) characteristics and should include acetylsalicylic acid as an intervention.

LEVEL OF EVIDENCE

I, network meta-analysis of Level I studies.

Lower total blood loss in total knee arthroplasty with a low-pressure tourniquet than without

Tourniquet-use has been described in litera- ture as a surgical factor leading to increased post-operative hidden blood loss in total knee arthroplasty (TKA). The hypothesis for this retro- spective study was that low-pressure tourniquet TKA would offer the benefits of tourniquet surgery without the potential negative effects on late blood loss after the procedure. Therefore, this study evaluated total (TBL) and hidden blood loss (HBL) in TKA with or without a tourniquet. We retrospectively compared two groups : one group (n= 54) undergoing TKA without a tourniquet and one group with a low-pressure tourniquet (n= 110). The outcomes compared were hemoglobin levels 2 weeks before surgery and at days 2 and 4 after surgery to calculate total and hidden blood loss, transfusion rate, and functional outcome. A higher total blood loss was observed in the no tourniquet group with a mean loss of 1073 mL against 890 mL in the tourniquet group (p-value = 0,003). Hidden blood loss values between both groups were statistically not significant : in the no-tourniquet group, Hb drop between D2 and D4 was 0.5 g/dL against 0.4 g/ dL in the low-pressure tourniquet group. The tourniquet-less group did not present with better functional scores. This study showed that low- pressure tourniquet use reduces TBL without increasing HBL in TKA.

Do We Need Chemoprophylaxis to Prevent Venous Thromboembolism following Medial Open-Wedge High Tibial Osteotomy?

The aim of this study was to investigate the overall incidence of venous thromboembolism (VTE) and to assess the efficacy of chemoprophylaxis to prevent VTE following medial open-wedge high tibial osteotomy (MOWHTO) in Asian patients. A total of 133 patients who consecutively underwent MOWHTO for the treatment of knee osteoarthritis with varus deformity were enrolled. All patients underwent preoperative ultrasonography and computed tomography venography on postoperative day 5 to detect deep vein thrombosis (DVT). Patients were divided into two groups: chemoprophylaxis group included patients (n = 66) who received 2.5 mg fondaparinux for 5 days postoperatively, whereas control group comprised patients (n = 67) who received placebo (67 patients). We evaluated the efficacy and safety outcomes of the treatment. We also assessed the predisposing factors that may affect the occurrence of VTE. The incidence of overall DVT was 14.9% in the control group and 10.6% in the chemoprophylaxis group (p > 0.05). Proximal DVT occurred in one patient in the control group. There was no symptomatic DVT or pulmonary embolism in either group. The patients with DVT had significantly higher mean body mass index (BMI) than the patients without DVT. Multivariate logistic regression showed BMI > 30 kg/m² that was significantly correlated with the development of DVT (odds ratio = 0.8; p = 0.017). There were no cases of major bleeding; however, minor bleeding episodes occurred in four patients in the chemoprophylaxis group. The current study showed that the overall incidence of VTE following MOWHTO was low in Asian patients even without chemoprophylaxis. Therefore, routine chemoprophylaxis following MOWHTO seems to be not necessary in a population with low-VTE incidence. However, selective chemoprophylaxis should be considered in patients with BMI > 30 kg/m².

2021 John N. Insall Award: Aspirin is effective in preventing propagation of infrapopliteal deep venous thrombosis following total knee arthroplasty

AIMS

The optimal management of an infrapopliteal deep venous thrombosis (IDVT) following total knee arthroplasty (TKA) remains unknown. The risk of DVT propagation and symptom progression must be balanced against potential haemorrhagic complications associated with administration of anticoagulation therapy. The current study reports on a cohort of patients diagnosed with IDVT following TKA who were treated with aspirin, followed closely for development of symptoms, and scanned with ultrasound to determine resolution of IDVT.

METHODS

Among a cohort of 5,078 patients undergoing TKA, 532 patients (695 TKAs, 12.6%) developed an IDVT between 1 January 2014 to 31 December 2019 at a single institution, as diagnosed using Doppler ultrasound at the first postoperative visit. Of the entire cohort of 532 patients with IDVT, 91.4% (486/532) were treated with aspirin (325 mg twice daily) and followed closely. Repeat lower limb ultrasound was performed four weeks later to evaluate the status of IDVT.

RESULTS

Follow-up Doppler ultrasound was performed on 459/486 (94.4%) patients and demonstrated resolution of IDVT in 445/459 cases (96.9%). Doppler diagnosed propagation of IDVT to the popliteal vein had occurred in 10/459 (2.2%) cases. One patient with an IDVT developed a pulmonary embolus six weeks postoperatively.

CONCLUSION

The results of this study demonstrate a low rate of IDVT propagation in patients managed with aspirin. Additionally, no significant bleeding episodes, wound-related complications, or other adverse events were noted from aspirin therapy. Cite this article: Bone Joint J 2021;103-B(6 Supple A):18-22.

Incidence of venous thromboembolism in Asian patients undergoing anterior cruciate ligament reconstruction without the use of mechanical or chemical prophylaxis

Background:

Venous thromboembolism (VTE) is a clinically relevant complication of major orthopedic surgeries. The prevalence of VTE and the indications for VTE thromboprophylaxis in Asian patients undergoing arthroscopic anterior cruciate ligament (ACL) reconstruction are not clear. This study aims to evaluate the prevalence of clinically significant venous thromboembolic events (VTE) in Asian patients undergoing arthroscopic ACL reconstruction without mechanical or chemical thromboprophylaxis.

Methods:

All patients who underwent ACL reconstruction by a single surgeon from 2006 to 2018 in a single tertiary institution were reviewed. The inclusion criteria for the study included Asian patients of common ethnic groups in Singapore (Chinese, Malay, Indian) and underwent primary or revision ACL reconstruction, or ACL reconstruction combined with meniscal surgery. The exclusion criteria were patients with incomplete medical records, pre-existing anticoagulant treatment within 1 year prior to the surgery and additional procedures that altered the standard rehabilitation protocol, less than 6 months of follow-up duration. All patients received general anesthesia. The single-bundle ACL technique with autologous hamstring tendon reconstruction was performed. No chemical DVT prophylaxis was given. The patients were screened for clinically for VTE. Symptomatic patients were referred for ultrasonography.

Results:

Of the 581 patients reviewed, 3 patients had a clinical suspicion of deep vein thrombosis, but subsequent ultrasonography showed no thrombosis. Hence, the prevalence of clinically significant VTE was 0%.

Conclusion:

Given the low prevalence of clinically significant VTE, there is no need for routine mechanical or chemical thromboprophylaxis or radiologic screening in Asian patients undergoing arthroscopic ACL reconstruction.

Unicompartmental knee arthroplasty and revision total knee arthroplasty have a lower risk of venous thromboembolism disease at 30 days than primary total knee arthroplasty

Background

While multiple studies have demonstrated a lower venous thromboembolism disease (VTED) risk for unicompartmental knee arthroplasty (UKA) compared to primary total knee arthroplasty (TKA), recent reports have shown that revision TKA also had a lower VTED risk compared to primary TKA, an unexpected finding because of its theoretical increased risk. Given the paucity of up-to-date comparative studies, our goal was to perform a high-powered VTED risk comparison study of UKA and revision TKA to primary TKA using recent data.

Methods

The National Surgical Quality Improvement Program (NSQIP) database was queried between 2011 and 2018, and we identified 213,234 patients for inclusion: 191,810 primary TKA, 9294 UKA, and 12,130 revision TKA. Demographics, medical comorbidities, and possible VTE risk factors were collected. Thirty-day outcomes, including deep vein thrombosis (DVT), pulmonary embolism (PE), and all-cause VTED were compared between knee arthroplasty types.

Results

On multivariate analysis, UKA was significantly associated with lower rates of DVT [OR 0.44 (0.31–0.61); P < 0.001], PE [OR 0.42 (0.28–0.65); P < 0.001], and all-cause VTED [OR 0.42 (0.32–0.55); P < 0.001] when compared to primary TKA. Revision TKA was significantly associated with lower rates of PE [OR 0.62 (0.47–0.83); P = 0.002], and all-cause VTED [OR 0.82 (0.70–0.98); P = 0.029] when compared to primary TKA.

Conclusions

Utilizing recent data from a nationwide patient cohort and controlling for confounding variables, our results showed that both revision TKA and UKA had a lower risk of VTED compared to primary TKA, corroborating the results of recent investigations. Additional prospective investigations are needed to explain this unexpected result.

The incidence and risk factor of deep venous thrombosis after arthroscopically assisted anterior cruciate ligament reconstruction

PURPOSE

To retrospectively analyze the incidence and risk factors of deep venous thrombosis (DVT) detected by ultrasonography after arthroscopically assisted Anterior Cruciate Ligament Reconstruction (ACLR).

METHODS

We retrospectively reviewed medical records of arthroscopically assisted ACLR surgery performed at our institution between 2012 and 2015. Revision ACLR, bone patella tendon bone (BTB) graft reconstruction, and concomitant multiple ligament reconstructions were excluded. We performed a standardized double-bundle reconstruction procedure using hamstrings graft for ACLR. All patients routinely received DVT screening by using venous ultrasonography on postoperative day 7 from 2012 to 2013, and postoperative days 7 and 14 from 2014 to 2015. The prevalence of DVT was calculated and clinical factors such as age, gender, Body Mass Index (BMI), operative time, and duration of tourniquet application were evaluated in relation to the risk factor of DVT.

RESULTS

Two hundred and fifty-six patients (129 men and 127 women) with a mean age of 28.9 were enrolled. Sixteen patients (6.6%) were detected with DVT on postoperative day 7. Among 146 patients who received venous ultrasonography on both postoperative days 7 and 14, DVT were detected in five additional patients on postoperative day 14. In a total of 21 patients who were diagnosed with DVT, two were proximal, the remaining 19 were distal, and no patient had progressed to pulmonary embolism (PE). In terms of predisposing factors for developing DVT on postoperative day 7, only age ≥30 showed a statistically significant higher risk of DVT (P = 0.03).

CONCLUSION

Incidence of DVT after ACLR detected by ultrasonography on postoperative day 7 was 6.6%. Patients aged ≥30 years have a potentially higher risk for developing DVT. Great care for DVT should be taken if prolonged immobilization is applied after ACLR surgery.

LEVEL OF EVIDENCE

Level Ⅳ.

Symptomatic Deep Vein Thrombosis Following Elective Knee Arthroscopy Over the Age of 40

Thromboprophylaxis following arthroscopic knee surgery (AKS) is not clear in the literature. The purpose of this study was to present the incidence of symptomatic deep vein thrombosis (DVT) following elective AKS over the age of 40. The secondary purpose was to investigate risk factors associated with venous thromboembolic events (VTEs). Surgical database and outpatient clinic follow-up charts of the patients who underwent AKS for any reason were included in the study. Odds for risk factors such as previous medical history of thrombosis, any family history for clotting disorders, diabetes mellitus (DM), oral contraceptive usage, body mass index, history of malignancy, and smoking were evaluated. The incidence of DVT following AKS significantly increased in the patients older than 40 years who had a previous medical history of VTE, DM, and smoking. A variety of guidelines exist for VTE prophylaxis; however, one should focus on risk factors related to the patient's medical history and current medical conditions. In this study, smoking, DM, and previous history of DVT increased DVT risk significantly, and thromboprophylaxis should be kept in mind for these patients.

Combined use of topical intraarticular tranexamic acid and rivaroxaban in total knee arthroplasty safely reduces blood loss, transfusion rates, and wound complications without increasing the risk of thrombosis

BACKGROUND

Blood loss and deep vein thrombosis (DVT) are important complications after total knee arthroplasty (TKA). Topical tranexamic acid (TXA) effectively reduces wound bleeding but may elevate the risk of DVT. In contrast, rivaroxaban potently prevents DVT but has been associated with bleeding complications. The simultaneous use of topical TXA and rivaroxaban in TKA has not been much investigated.

METHODS

A retrospective cohort study was conducted with two consecutive groups of patients who underwent TKA. Intraoperatively, one group (RVTX group) received topical, intraarticular TXA, while the other (RV group) did not. Both groups were administered rivaroxaban postoperatively for 14 days and underwent Doppler ultrasound for DVT screening. After propensity score matching, both groups consisted of 52 patients (104 patients in total) and were compared regarding total drain output, nadir haemoglobin (Hb), maximum Hb decrease, calculated total blood loss, transfusion rate, and incidence of DVT and wound complications.

RESULTS

Both groups showed no significant differences in the propensity-matched variables of age, sex, body mass index, American Society of Anesthesiologists physical status score, and preoperative Hb. The RVTX group showed a significantly higher nadir Hb (p < 0.001), lower drain output (p < 0.001), Hb decrease (p = 0.015), total blood loss (p < 0.001), and rate of transfusion (p < 0.001) and fewer wound complications (p = 0.027). However, the incidence of DVT (p = 1.000) did not differ significantly between the two groups, and all cases were asymptomatic.

CONCLUSIONS

The combined use of intraarticular topical TXA with rivaroxaban in patients undergoing TKA is a safe and effective method to reduce blood loss, the need for transfusion, and wound complications without elevating the risk of DVT.

Comparing the Effect of Tourniquet vs Tourniquet-Less in Simultaneous Bilateral Total Knee Arthroplasties

BACKGROUND

Total knee arthroplasty (TKA) is a commonly performed procedure worldwide for the treatment of knee joint disease. Tourniquet is frequently used during the entire procedure to reduce blood loss and increase surgical comfort. On the other hand, tourniquet-related complications exist, and there are still controversies whether benefits outweigh the risks.

METHODS

Patients undergoing simultaneous TKAs had one knee assigned to group A (use of tourniquet during the entire procedure) and the other knee assigned to group B (use of tourniquet only during cementation). Blood loss, intraoperative complications, implant alignment, soft tissue swelling, pain score, and range of motion were analyzed.

RESULTS

Fifty-four patients undergoing 108 TKAs were included in the study. Total blood loss was almost 2 times higher in group B knees compared with group A. No difference was observed between groups in implant alignment, soft tissue swelling, pain, range of motion, or other early postoperative complications.

CONCLUSION

Tourniquet use in TKAs during the entire surgical procedure reduces total blood loss, without an increase in early postoperative complications.

CT pulmonary angiography in lower limb arthroplasty

Aims

The aims of this study were to determine the indications and frequency of ordering a CT pulmonary angiography (CTPA) following primary arthroplasty of the hip and knee, and to determine the number of positive scans in these patients, the location of emboli and the outcome for patients undergoing CTPA.

Patients and Methods

We analyzed the use of CTPA, as an inpatient and up to 90 days as an outpatient, in a cohort of patients and reviewed the medical records and imaging for each patient undergoing CTPA.

Results

Out of 11 249 patients, scans were requested in 229 (2.04%) and 86 (38%) were positive. No patient undergoing CTPA died within 90 days. The rate of mortality from pulmonary embolism (PE) overall was 0.08%. CTPA was performed twice as often following total knee arthroplasty (TKA) compared with total hip arthroplasty (THA), and when performed was twice as likely to be positive. Hypoxia was the main indication for a scan, being the indication in 149 scans (65%); and in 23% (11 of 47), the PE was peripheral and unilateral. Three patients suffered complications resulting from therapeutic anticoagulation for possible PE, two of whom had a negative CTPA.

Conclusion

CTPA is more likely to be performed following TKA compared with THA. Hypoxia was the main presenting feature of PE. A quarter of PEs which were diagnosed were unilateral and peripheral. Further study may indicate which patients who have a PE after lower limb arthroplasty require treatment, and which can avoid the complications associated with anticoagulation. Cite this article: Bone Joint J 2018;100-B:938–44.

VTE primary prevention, including hospitalised medical and orthopaedic surgical patients

Primary prevention is the key to managing a significant proportion of the burden of venous thromboembolism (VTE), defined as deep venous thrombosis (DVT) or pulmonary embolism (PE). This is because VTE may lead to sudden death or are often misdiagnosed and therefore treatment is not feasible. Primary prevention usually commences in hospital as VTE following hospitalisation adds to the significant disease burden worldwide. Numerous medical, surgical and other risk factors have been recognised and studied as indications for prophylaxis. The risk of VTE continues following admission to hospital with a medical or surgical condition, usually long after discharge and therefore prolonged primary prophylaxis is often recommended. Clinical and observational studies in surgical patients show this risk extends for months and perhaps more than one year, for medical patients the risk extends for at least several weeks. For the specific groups of patients at higher risk of developing VTE primary prevention, either pharmaceutical or mechanical, is recommended. The aim of this review is to describe the population at risk, the main related risk factors and the approach to thromboprophylaxis in different populations.

Incidence and risk factors of deep venous thrombosis following arthroscopic posterior cruciate ligament reconstruction

The objective of this study was to identify the incidence and associated risk factors for deep venous thrombosis (DVT) after arthroscopic posterior cruciate ligament (PCL) reconstruction.This study included 128 patients who underwent arthroscopic PCL reconstruction. Venography was performed on the operated leg 3 days postoperatively. The patients were divided into 2 groups based on whether they had DVT. A correlation analysis was performed to determine the factors associated with DVT.Of all the 128 patients, 28 patients (21.9%) developed DVT, with 4 (3.1%) in a proximal location. Significant differences were found in the mean age, time of application of tourniquet, mean VAS scores, mean D-dimer level, mean cholesterol level, and various surgical procedures in patients with DVT compared with those without DVT. DVT is difficult to diagnose solely based on clinical symptoms.The incidence of DVT was 21.9% in patients who underwent arthroscopic PCL reconstruction. The rate of asymptomatic clots in the calf region was rather high after PCL reconstruction, and the rate of proximal clots was 4%. Older age, longer durations of tourniquet application, higher VAS scores and D-dimer levels, and complex surgical procedures were all substantial risk factors for DVT after PCL reconstruction. The treatment of DVT with batroxobin and anticoagulants was effective and safe.

Evaluation of costs and outcomes associated with pharmacological thromboprophylaxis (unfractionated heparin and low molecular weight heparins) of venous thromboembolism at orthopedic ward in Clinical Hospital Stip

Clinical trials have shown Low-molecular weight heparins (LMWHs) to be at least as safe and efficacious as unfractionated heparin (UFH) for preventing venous thromboembolism (VTE) in patients undergoing major orthopedic surgery who are at highest risk of developing VTE. The retrospective study was conducted at orthopedic department in Clinical Hospital – Stip for period of 12 months (January-December 2013), where LMWHs and UFH are accepted thromboprophylaxis options. 320 patients (144 males and 157 females, medium age 58 years and 70 years, respectively) were hospitalized for various types of major orthopedic surgical interventions. 212 (66%) patients were admitted because of hip or knee fractures, 26 (8%) had conditions after hip or knee fractures and 82 (26%) were hospitalized for removal or implanting of osteosynthetic devices. After the surgical intervention, patients were subjected to anticoagulant prophylaxis (UFH or LMWHs). Which type of prophylaxis will be used depended exclusively on the surgeon’s decision. VTE complications resulting death were observed in 8 (2.5%) out of 13 patients. Death because of PE occurred in 2 (25%) out of 8 patients, compared to 6 (75%) patients who had fatal DVT complications. The average hospital cost for patients treated with LMWHs prophylaxis as first line thromboprophylaxis option was 52831.92 MKD/patient compared to 70082.24 MKD/patient for UFH first line thromboprophylaxis option. We observed that LMWHs thromboprophylaxis, applied in recommended doses subcutaneously once a day, is potentially more effective and cost saving option compared to UFH and should be considered as pharmacological treatment of first choice for the prevention of VTE (DVT and PE) in patients recovering from major orthopedic surgery at the orthopedic department in Clinical Hospital Stip. Keywords: Thromboprophylaxis, major orthopedic surgery, LMWHs, UFH

A panel of microRNAs as a new biomarkers for the detection of deep vein thrombosis

Deep vein thrombosis is one of the common complications of orthopedic surgery, and pulmonary embolism which is one of its lethal complications can lead to mortality. Numerous efforts have been made to identify reliable and predictive biomarkers to detect the early signs of deep vein thrombosis. These studies have, however, not delivered any more informative candidates than the D-dimer that have been available. Cell-free microRNAs are present in a range of body fluids and have recently been shown to be useful biomarkers in many diseases. Therefore, the purpose of present study was to identify potential microRNA biomarkers of deep vein thrombosis that are present in serum. Serum samples were taken from 18 deep vein thrombosis patients and 20 age- and sex-matched controls. TaqMan microRNA array was used for an initial screening. Real-time PCR assay was implemented to confirm the concentrations of candidate microRNAs. We found that the serum levels of miR-582, miR-195 and miR-532 of deep vein thrombosis patients were higher than those of controls. miR-582 yielded an AUC (the areas under the ROC curve) of 0.959, and the other two microRNAs yielded an AUC of 1.000 in discriminating deep vein thrombosis from controls. These data hint that serum miR-582, miR-195 and miR-532 might have potential to be a novel noninvasive biomarkers for detection of DVT. And this is the first study suggesting that serum microNRAs might be used as biomarkers for deep vein thrombosis.

Bilateral adrenal hemorrhage in a total knee patient associated with enoxaparin usage

Bilateral adrenal hemorrhage is a rare but potentially catastrophic complication of chemoprophylaxis. We report a patient who underwent a total knee arthroplasty and subsequently developed bilateral adrenal hemorrhage from enoxaparin. Once the patient was diagnosed with acute adrenal insufficiency, corticosteroids were promptly started, and the patient made a dramatic recovery and did not suffer further complications.

Venous thromboembolism incidence in upper limb orthopedic surgery: do these procedures increase venous thromboembolism risk?

BACKGROUND

In 2005, the House of Commons (HoC) Health Committee stated deaths attributed to preventable, hospital-acquired venous thromboembolism (VTE) numbered upwards of 25,000 per annum. Nationwide prevention of VTE became the topic of a major health campaign. The HoC Health Committee stated there was an unstratified VTE risk of between 45% and 51% associated with orthopedic surgery. VTE research in orthopedic surgery has been concentrated on lower limb procedures. Experience suggests that this kind of relation does not hold true for upper limb orthopedic procedures. This project aimed to estimate the incidence of postoperative VTE in upper limb orthopedic surgery.

METHODS

The incidence of postoperative VTE was assessed in 3357 consecutive upper limb orthopedic operations performed by 4 surgeons in Lancashire Teaching Hospitals National Health Service (NHS) Trust (LTHTR) between July 1, 2009, and July 31, 2012.

RESULTS

Four pulmonary embolisms and 2 deep vein thromboses occurred. Incidence of postoperative VTE was 0.0018%, significantly lower than rates reported in the literature. Five of 6 patients who developed a VTE reported a personal or family history of VTE. Three patients would not have been identified as at risk under the current VTE screening guidelines. Three of these patients received appropriate anticoagulation according to present guidelines, yet VTE events still occurred.

CONCLUSION

These results indicate VTE risk in orthopedic upper limb surgery is much lower than reported in the literature. The necessity for screening for VTE in upper limb surgery is contested. The efficacy of VTE screening and current VTE prophylaxis is discussed, and an alternative and much simplified method of screening is suggested.

Low frequency of symptomatic venous thromboembolism after multiligamentous knee reconstruction with thromboprophylaxis

BACKGROUND

Reconstruction of the multiligament-injured knee often involves extended surgical and tourniquet use times and often is performed in patients who have sustained concomitant fractures as well as vascular injuries, all of which would appear to predispose the patient to the potentially serious complications of deep vein thrombosis and perhaps pulmonary embolism, yet little is known about the frequency of venous thromboembolic (VTE) events after multiligamentous knee reconstruction.

QUESTIONS/PURPOSES

The purposes of this study were to (1) determine the frequency of symptomatic VTE after multiligamentous knee reconstruction at a single institution; and (2) to determine associated risk factors for VTE in these patients.

METHODS

The records of 134 (63% of the 213 consented individuals in our longitudinal database) patients who underwent primary (129 [96%]) or revision (five [4%]) multiligamentous knee reconstruction at a single institution between 1992 and 2013 were retrospectively reviewed. With two patients undergoing procedures bilaterally, this resulted in a total of 136 multiligamentous knee reconstructions. VTE for which clinical symptoms were evident and confirmed by imaging within 3 months after the reconstructive procedure was noted. Pre- and perioperative data were collected with respect to demographics, associated injuries, medical history, smoking status, and surgical data. Standard rehabilitation and thromboprophylaxis protocols were used in all patients.

RESULTS

Three cases of symptomatic VTE (three deep vein thromboses) occurred after the 136 reconstructions (2%; 95% confidence interval, 0.53%-7.3%). Two of the three patients were obese and the remaining patient smoked and abused alcohol. However, as a result of a low frequency of VTE, no risk factors could be identified in this series.

CONCLUSIONS

Symptomatic VTE occurred in 2% of multiligamentous knee reconstructions at our institution while receiving thromboprophylaxis. This is similar to rates documented after anterior cruciate ligament reconstruction without thromboprophylaxis. Further multicenter research is required to identify the true frequency of and risk factors for developing VTE in patients undergoing multiligamentous knee reconstruction after knee dislocation.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Incidence of symptomatic and asymptomatic venous thromboembolism after elective knee arthroscopic surgery: a retrospective study with routinely applied venography

PURPOSE

The purpose of this study was to assess the incidence of total venous thromboembolism (VTE) after knee arthroscopy with routinely applied venography.

METHODS

We reviewed 537 consecutive patients undergoing arthroscopic knee surgery from March 2012 to July 2013. The surgical procedure was categorized as simple anterior cruciate ligament reconstruction (ACLR), posterior cruciate ligament reconstruction (PCLR), or reconstruction of both cruciate ligaments. All patients having arthroscopy in our institution were routinely examined with venography on the third postoperative day. Clinical signs of DVT were checked and recorded before venography.

RESULTS

Eighty (14.9%) of 537 patients were diagnosed with VTE by venography. Of the 80 detected cases of VTE, only 20 (3.7%) patients presented with clinical signs of DVT, indicating that there were 60 (11.2%) asymptomatic cases. No patient died or presented with a clinically suspected pulmonary embolism (PE). Sex, body mass index (BMI), operative time, and duration of tourniquet application were not significant risk factors for DVT. Patient age (P < .0001) is a strongly significant risk factor for deep venous thrombosis (DVT). Compared with patients who underwent simple arthroscopic procedures, complex procedures-the reconstruction of 1 (P < .005) or both knee cruciate ligaments (P < .0005)-led to a significantly higher postoperative incidence of DVT.

CONCLUSIONS

The total incidence of VTE diagnosed with venography after arthroscopic knee surgery was 14.9%, of which only 3.7% of cases were symptomatic, indicating 11.2% cases of silent VTE. Advanced age and complex arthroscopic surgery are strongly associated with VTE.

LEVEL OF EVIDENCE

Level IV, prognostic case series.

Deep venous thrombosis after knee arthroscopy: a systematic review and meta-analysis

PURPOSE

To establish a contemporary literature-based estimate of the incidence of deep venous thrombosis (DVT) after knee arthroscopic surgery.

METHODS

We performed a systematic review and meta-analysis of the English language literature to assess the efficacy of prophylaxis to prevent DVT after knee arthroscopic surgery. Only randomized controlled trials (RCTs) or prospective studies were considered. Studies were excluded if they were not original prospective studies concerning DVT detected by imaging after knee arthroscopic surgery. We calculated pooled proportions of postoperative DVT and proximal DVT.

RESULTS

Nine prospective uncontrolled studies and 4 RCTs were retrieved. Within them, the populations given low-molecular-weight heparin (LMWH) to prevent DVT had a 0.1% to 11.9% incidence of DVT, with an overall 36 DVTs identified (4 proximal), averaging 1.8%. One hundred thirty-six DVTs (29 proximal) were indicated in the populations without prophylaxis, and the DVT incidence varied from 1.8% to 41.2%, averaging 6.8%. Of the RCTs, the pooled risk ratio for DVT to develop was 0.180 (range, 0.065 to 0.499) for those who had LMWH as prophylaxis. An absolute risk reduction of 1.2%--from 1.5% to 0.3%--for the development of proximal DVT was observed.

CONCLUSIONS

Compared with patients who did not receive prophylaxis, the pooled risk ratio for the development of DVT was 0.18 for those who had LMWH prophylaxis. The incidence of proximal DVT is very low after arthroscopic surgery regardless of receiving prophylaxis (4 of 2,184) or not (29 of 1,814). The rate of proximal DVT in total DVT occurrence can be markedly reduced from 21.3% (29 of 136) to 11.1% (4 of 36).

LEVEL OF EVIDENCE

Level IV. This study is a meta-analysis of RCTs and a systematic review of Level IV studies.

Thromboembolic complications in arthroscopic surgery

Venous thromboembolism (VTE) is a relatively rare complication of arthroscopic surgery but has the potential to cause significant morbidity and even mortality. VTE has been reported after shoulder and knee arthroscopy prompting controversial guidelines to be proposed. More limited studies are available regarding hip and ankle arthroscopy and 1 case of deep venous thrombosis in the contralateral leg status after hip arthroscopy exists. No reports have been published regarding VTE after elbow or wrist arthroscopy to these authors' knowledge. In this article, a systematic review of the literature was conducted to analyze the incidence, treatment, and prevention of thromboembolic complications in arthroscopy.

The use of pneumatic tourniquets is safe in Asians undergoing total knee arthroplasty without anticoagulation

BACKGROUND

There has always been controversy surrounding the use of pneumatic tourniquets in total knee arthroplasty (TKA) as they have been implicated in venous thromboembolic events (VTE). We aimed to evaluate the incidence of clinically significant VTE in Asians who underwent conventional TKA under tourniquet throughout the duration of surgery, without post-operative chemical VTE prophylaxis, but using post-operative pneumatic compression devices.

METHODS

Five hundred and thirty-one patients of a single surgeon who underwent elective total knee arthroplasty were retrospectively reviewed. All patients had a tourniquet applied to the operated limb. None of the patients received chemoprophylaxis against VTE. Post-operatively, only symptomatic patients were referred for ultrasonography. The patients were then stratified according to the tourniquet time: <60, 61 to 90, 91 to 120, and >120 min. The overall incidence as well as the incidence of venous thromboembolic events for each group was then calculated.

RESULTS

Of the 531 patients reviewed, 3 patients suffered from deep venous thrombosis (DVT) while 1 patient developed a fatal pulmonary embolism (PE). Hence, the overall incidence of clinically significant VTE was 0.75%. The 3 patients with DVT had tourniquet time of 61 to 90 min while the patient with PE had a tourniquet time of more than 120 min.

CONCLUSION

With a low overall incidence of VTE, the use of tourniquet in Asians during conventional total knee arthroplasty appears safe when post-operative pneumatic compression devices are used instead of chemical VTE prophylaxis. However, the risk of VTE seems to increase with a tourniquet time of more than 60 min.

LEVEL OF EVIDENCE

Therapeutic studies, level III.

DVT prophylaxis after TKA: routine anticoagulation vs risk screening approach - a randomized study

The American College of Chest Physicians (ACCP) recommended routine anticoagulation for thromboprophylaxis in patients undergoing lower limb arthroplasty. We compared results of routine anticoagulation Vs risk stratified approach for Deep Venous Thrombosis (DVT) prophylaxis after TKA in terms of symptomatic DVT and wound complications. Nine hundred TKAs done in 673 patients were randomized after DVT risk screening to routine anticoagulation (n = 450) or to risk stratification (n = 450) and selective anticoagulation. 194 patients in the risk screening group received only Aspirin. Primary outcome was symptomatic DVT and wound complication. This randomized study showed that the symptomatic DVT rates after TKA were similar whether patients were routinely anticoagulated or selectively anticoagulated after risk screening. However there was a significantly higher incidence of wound complications (P < 0.014) after routine anticoagulation.

[Compliance of patients undergoing thromboprophylaxis with enoxaparin: the COMFORT study]

Venous thromboembolism and subsequent pulmonary embolism are frequent and sometimes fatal complications in patients after surgical interventions. To prevent thromboembolisms an effective prophylaxis is necessary and outpatients in particular need adequate compliance. The aim of the prospective non-interventional study COMFORT was to analyze 8,091 outpatients after surgical and orthopedic interventions with different risk profiles with respect to factors affecting patient compliance in a positive or negative way. The follow-up period was 14 days and 92.5 % of the patients took the medication for the prescribed duration, 2.1 % (n = 166) terminated the medication too early and no information was available for 5.9 % (n = 442) of the patients. The reasons given for the premature termination of the injections were no more need for prophylaxis and end of medication by order of the physician due to mobilization or adverse events. Of the patients 73 % stated that the administartion was simple and without any problems and the majority of patients recognized injection as the administration mode of low molecular weight heparin to be the most important medication. The findings of this study can contribute to a better understanding of patient compliance.

Venous thromboembolism after laparoscopic biliopancreatic diversion with duodenal switch: analysis of 362 patients

BACKGROUND

Venous thromboembolism (VTE), which manifests as deep venous thrombosis (DVT) or pulmonary embolism (PE), is relatively uncommon after weight loss procedures but has the strong potential to affect patient morbidity and mortality. This type of complication has been studied extensively in more common weight loss procedures, such as Roux-en-Y gastric bypass (RYGB). VTE has not been studied after biliopancreatic diversion with duodenal switch (BPD-DS), a bariatric procedure performed mainly for super morbidly obese patients, who are inherently associated with a higher incidence of co-morbidity. The objective of this study was to review VTE prevalence and identify risk factors associated with the postoperative occurrence of VTE in a collected data set of patients after laparoscopic BPD-DS.

METHODS

The database of all patients who underwent laparoscopic BPD-DS between 2006 and 2012 was reviewed. Preoperative clinical information, which included history of VTE, inferior vena cava (IVC) filter placement, operative variables, and postoperative course, were reviewed. All VTE related events that occurred within 90 days postoperatively were collected and analyzed.

RESULTS

Of 362 patients who underwent laparoscopic BPD-DS during the study period, 12 (3.3%) experienced a VTE complication. Eight (2.2%) patients presented with DVT; 4 (1.1%) patients presented with PE. VTE complications were more common in females than males (83.3% versus 16.6%, respectively). Age, body mass index (BMI), and time interval between preoperative and postoperative doses of heparin for DVT prophylaxis did not influence the occurrence of VTE complications. However, operative time (P = .02) and length of hospital stay (P = .0005) were identified as risk factors associated with postoperative VTE complications. No related mortality occurred in this study.

CONCLUSION

The prevalence of VTE after BPD-DS is relatively low and comparable to other weight loss procedures. Overall risk of postoperative VTE after laparoscopic BPD-DS appears to be associated with the length of operation and hospital stay.

Rivaroxaban is as efficient and safe as bemiparin as thromboprophylaxis in knee arthroscopy

PURPOSE

The aim of this study is to compare effectiveness and safety profile of rivaroxaban with bemiparin in 3-week extended prophylaxis after knee arthroscopy.

METHODS

Four hundred and sixty-seven patients were included in this review divided in two groups. One followed prophylaxis with rivaroxaban and the other one with bemiparin. All patients were interviewed and explored at 1 and 3 months postoperatively, looking for symptomatic signs of deep-vein thrombosis (DVT). In case of suspicion, diagnostic tests were performed. Collected data were age, sex, gender, diagnosis, time with ischemia, body mass index, concomitant diseases, concomitant therapy, DVT signs, treatment satisfaction, minor and major complications, treatment adherence and tolerability.

RESULTS

No thromboembolic events were observed in any of the groups. In one case treated with rivaroxaban, the drug had to be withdrawn due to epistaxis.

CONCLUSIONS

Our study showed that extended prophylaxis with 10 mg of rivaroxaban once daily for 3 weeks resulted as effective as bemiparin in knee arthroscopy thromboprophylaxis.

The incidence of deep venous thrombosis after arthroscopically assisted anterior cruciate ligament reconstruction

PURPOSE

The purpose of our study was to retrospectively assess and analyze the incidence of deep venous thrombosis (DVT) after arthroscopically assisted anterior cruciate ligament reconstruction (ACLR) at our institution.

METHODS

We conducted a retrospective analysis of 249 arthroscopic ACLRs performed in our hospital between February 2009 and February 2012. The surgical procedure was standardized in all the patients and was conducted by the same 2 surgeons. Quadrupled hamstring autograft was used in all the patients. No patient was given nonsteroidal anti-inflammatory drugs for the first 2 weeks after surgery. A unilateral contrast venography examination was performed on the third postoperative day. Patients were confined to bed once DVT was confirmed, followed by therapeutic doses of batroxobin. The proportion of patients with DVT was calculated. The significance of the association between clinical factors and postoperative DVT was determined.

RESULTS

This study included 171 patients (123 men and 48 women), with a mean age (±SD) of 30.1 ± 10.0 years. DVT was detected in 24 patients (14.0%; 95% confidence interval, 8.8% to 19.3%). Body mass index (BMI), operative time, operator, and duration of tourniquet application were not significant risk factors for DVT. The risk of DVT was significantly higher in patients aged 35 years or older (P < .01). Higher risk for DVT was also identified in female patients (P < .05). Pulmonary embolism did not develop after thrombolytic therapy in any of the 24 patients with DVT after ACLR.

CONCLUSIONS

The incidence of DVT in patients who underwent arthroscopic ACLR was 14% in this study. Female patients and those aged 35 years or older have a significantly higher risk of DVT developing after ACLR; thus thromboprophylaxis is advocated in these patients.

LEVEL OF EVIDENCE

Level IV, therapeutic case series.

Hemostatic matrix effects on blood loss after total knee arthroplasty: A randomized controlled trial

BACKGROUND

Total knee arthroplasty (TKA) can result in major postoperative blood loss which can impact on the recovery and rehabilitation of patients. It also requires expensive transfusions. The purpose of the study was to investigate whether a hemostatic matrix, composed of cross-linked gelatin and a thrombin solution, would reduce blood loss in patients following TKA.

MATERIALS AND METHODS

THIS WAS A PROSPECTIVE, RANDOMIZED, CONTROLLED STUDY (TRIAL REGISTRATION: Hospital S. Salvatore L'Aquila ADJ00843) conducted in 93 patients. Criteria for participation were unilateral TKA for osteoarthritis, and a preoperative hemoglobin level >13 g/dL. The outcomes measured were postoperative hemoglobin and hematocrit levels measured at 24h, 72 h, and 7 days. The mean total postoperative blood loss was calculated from drainage volume, patient blood volume, hematocrit, and red blood cell volume. In addition, the drain output within 24 h following surgery and any transfusion requirements were determined.

RESULTS

Hemostatic matrix-treated patients (n = 51) showed significant reductions in calculated postoperative blood loss of 32.3% and 28.7% versus control in men and women, respectively (P < 0.01). Postoperative blood loss after 24 h in drain was significantly less with the hemostatic matrix versus control, as were decreases in hemoglobin levels 7 days post-surgery (each P < 0.01). Three patients in the control group required blood transfusion, whereas no blood transfusions were necessary in the hemostatic matrix group.

CONCLUSION

The use of a hemostatic matrix provides a safe and effective means to reduce blood loss and blood transfusion requirements in TKA.

Efficacy of intra-articular tranexamic acid in blood loss reduction following primary unilateral total knee arthroplasty

PURPOSE

The surgical stress of total knee arthroplasty (TKA) procedure and the application of intra-operative pneumatic thigh tourniquet increases local fibrinolytic activity, which contributes significantly to post-operative blood loss. Tranexamic acid, an antifibrinolytic drug, is commonly used to control post-operative blood loss. The recommended mode of administration of tranexamic acid is either oral or intravenous. However, the mechanism of action of the tranexamic acid points towards the possible effectiveness it may have following local/intra-articular application. This prospective, double-blinded, randomized preliminary study evaluated the efficacy of intra-articular tranexamic acid in reducing TKA-associated post-operative blood loss.

METHODS

Fifty consenting patients with osteoarthritis of the knee scheduled for primary unilateral cemented-TKA were randomly allocated to one of the two groups: Tranexamic Acid (TA) group (n = 25, 500 mg/5 ml tranexamic acid) and the control group (n = 25, 5 ml 0.9% saline). The drug and control solution were administered intra-articularly through the drain tube immediately after the wound closure. Parameters related to blood loss (drop in haemoglobin, haematocrit differential) and the drain output [volume (ml)] were compared between the two groups.

RESULTS

On a comparative basis, TA-group obtained significant reduction in the drain output [95% CI: 360.41-539.59, p < 0.001] at 48 h post-operatively. Even though the control group received sixfold more blood transfusion than TA-group, it showed a greater drop in haemoglobin and haematocrit (p < 0.05).

CONCLUSIONS

Local application of tranexamic acid seems to be effective in reducing post-TKA blood loss as well as blood transfusion requirements.

LEVEL OF EVIDENCE

Therapeutic study, Level II.

Paradoxical cerebral embolism after total knee arthroplasty

Deep vein thrombosis is a frequent complication following total joint arthroplasty and other major orthopedic procedures. Pulmonary embolism occurs with or without a diagnosis of deep vein thrombosis, although infrequently (1.5%-10%). In patients with congenital cardiac defects, such as a patent foramen ovale, paradoxical cerebral embolism may also occur. This article describes a case of a 52-year-old woman who sustained a paradoxical cerebral embolism following total knee arthroplasty. In the workup of a patient with a known murmur and stroke symptoms, paradoxical cerebral embolism should be included in the differential. The initial evaluation should incorporate transesophageal echocardiography because of its accuracy in the demonstration of the cardiac physiology. An abnormal intracardiac or intrapulmonary shunt is essential for paradoxical cerebral embolism, allowing the entrance of the thrombus into cerebral circulation from the venous system. No clear consensus has been reached on the management of patients at risk for paradoxical cerebral embolism prior to orthopedic procedures. However, when an embolic stroke is diagnosed acutely, ideal management includes thrombolytic therapy, but further research is needed to confirm that this is the correct management. Due to the risk of recurrence, postoperative thromboprophylaxis is recommended with or without closure of the foramen ovale. Most importantly, and as demonstrated by the current patient, who partially recovered but did not require walking assistance after 2-year follow-up, treating physicians should be prepared to counsel patients through a lengthened physical rehabilitative process.

The influence of tourniquet use and operative time on the incidence of deep vein thrombosis in total knee arthroplasty

OBJECTIVE

To evaluate the association between tourniquet and total operative time during total knee arthroplasty and the occurrence of deep vein thrombosis.

METHODS

Seventy-eight consecutive patients from our institution underwent cemented total knee arthroplasty for degenerative knee disorders. The pneumatic tourniquet time and total operative time were recorded in minutes. Four categories were established for total tourniquet time: <60, 61 to 90, 91 to 120, and >120 minutes. Three categories were defined for operative time: <120, 121 to 150, and >150 minutes. Between 7 and 12 days after surgery, the patients underwent ascending venography to evaluate the presence of distal or proximal deep vein thrombosis. We evaluated the association between the tourniquet time and total operative time and the occurrence of deep vein thrombosis after total knee arthroplasty.

RESULTS

In total, 33 cases (42.3%) were positive for deep vein thrombosis; 13 (16.7%) cases involved the proximal type. We found no statistically significant difference in tourniquet time or operative time between patients with or without deep vein thrombosis. We did observe a higher frequency of proximal deep vein thrombosis in patients who underwent surgery lasting longer than 120 minutes. The mean total operative time was also higher in patients with proximal deep vein thrombosis. The tourniquet time did not significantly differ in these patients.

CONCLUSION

We concluded that surgery lasting longer than 120 minutes increases the risk of proximal deep vein thrombosis.

Complications of arthroscopic meniscectomy in the older population

BACKGROUND

Complications of arthroscopic meniscectomy in the older population have not been established.

PURPOSE

To determine the risk and relative risk of developing pyogenic arthritis (PA), a deep vein thrombosis (DVT), and pulmonary embolism (PE) in an older population of patients who have undergone arthroscopic meniscectomy.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Men and women ≥65 years old who underwent procedures coded as CPT-29880 (medial and lateral meniscectomy) and CPT-29881 (medial or lateral meniscectomy) were identified in the Medicare Standard Analytic Files database from 2005 to 2008. Identified patients were analyzed for gender and postoperative complications, including PA, DVT, and PE, occurring within 90 days of the index operation.

RESULTS

Overall, 314,578 patients (119,814 men and 194,764 women) were identified. With respect to the Current Procedural Terminology codes, 131,420 patients were coded 29880 and 183,158 patients were coded 29881. In the study population, 0.4% (1107 patients) developed PA, 0.8% (2507 patients) developed a DVT, and 0.3% (982 patients) developed a PE. Among male patients, 0.4% developed PA, 0.7% developed a DVT, and 0.2% developed a PE. Among female patients, 0.3% developed PA, 0.8% developed a DVT, and 0.3% developed a PE. Overall, men had a statistically significant higher relative risk of PA and women had a statistically significant higher relative risk of DVT and PE.

CONCLUSION

Postoperative complications, including PA, DVTs, and PEs, are rare in patients ≥65 years old. However, gender-specific differences in the rate and type of postoperative complications may exist. Further studies in this population are warranted.

Incidence of venous thromboembolism using 64 channel multidetector row computed tomography-indirect venography and anti-coagulation therapy after total knee arthroplasty in Korea

Purpose

This study evaluated the incidence of a venous thromboembolism (VTE) after total knee arthroplasty (TKA) using multidetector row computed tomography-indirect venography (MDCT-indirect venography) and assessed the efficacy of anti-coagulation therapy.

Materials and Methods

We enrolled 118 patients with 126 cases of TKA. The average age of the patients was 68.4 years. We used 64 channel MDCT-indirect venography for the detection of VTE. We treated selectively proximal deep vein thrombosis (DVT) or pulmonary thromboembolism (PTE) cases according to the results of MDCT-indirect venography. We re-evaluated the change in VTE using follow-up MDCT-indirect venography after 3 months.

Results

We identified VTE in 35.7%. DVT only was identified in 22.2% including 8 cases of proximal DVT and 20 cases of distal DVT. PTE without DVT was identified in 4.8%, and combined DVT and PTE in 8.7%. All patients with PTE were asymptomatic, but 4 DVT patients had signs of leg swelling. After anti-coagulation therapy, 20 patients showed complete resolution in 16 cases, improvement in 3 cases and one case showed a new distal DVT.

Conclusions

The incidence of VTE after primary TKA was 35.7% in Korea. Furthermore, anti-coagulation therapy for proximal DVT and PTE patients may be a useful method for preventing the occurrence of a fatal PTE.

Operative risk of staged bilateral knee arthroplasty is underestimated in retrospective studies

To find a safer surgical option, a number of studies have compared postoperative complications after bilateral total knee arthroplasty vs staged total knee arthroplasty (STKA) by contrasting postoperative complications collected retrospectively. However, we believe that a comparison based on retrospective studies could be biased. The purpose of this study was to demonstrate the misclassification bias associated with a retrospective study in comparing operative outcomes. Our analysis indicates that any conclusions based simply on retrospective analysis of subjects who successfully completed STKA is biased because it includes only cases that recovered after the first operation, rather than all of the patients who had planned STKA. In the absence of a prospective study to date, published studies should be interpreted with caution.

Are current thrombo-embolic prophylaxis guidelines applicable to unicompartmental knee replacement?

Symptomatic and asymptomatic deep-vein thrombosis (DVT) is a common complication of knee replacement, with an incidence of up to 85% in the absence of prophylaxis. National guidelines for thromboprophylaxis in knee replacement are derived from total knee replacement (TKR) data. No guidelines exist specific to unicompartmental knee replacement (UKR). We investigated whether the type of knee arthroplasty (TKR or UKR) was related to the incidence of DVT and discuss the applicability of existing national guidelines for prophylaxis following UKR.

Data were collected prospectively on 3449 knee replacements, including procedure type, tourniquet time, surgeon, patient age, use of drains and gender. These variables were related to the incidence of symptomatic DVT.

The overall DVT rate was 1.6%. The only variable that had an association with DVT was operation type, with TKR having a higher incidence than UKR (2.2% versus 0.3%, p < 0.001). These data show that the incidence of DVT after UKR is both clinically and statistically significantly lower than that after TKR.

TKR and UKR patients have different risk profiles for symptomatic DVT. The risk-benefit ratio for TKR that has been used to produce national guidelines may not be applicable to UKR. Further research is required to establish the most appropriate form of prophylaxis for UKR.

Risk factors for symptomatic deep-vein thrombosis in patients after total ankle replacement who received routine chemical thromboprophylaxis

The aim of this study was to identify the incidence of post-operative symptomatic deep-vein thrombosis (DVT), as well as the risk factors for and location of DVT, in 665 patients (701 ankles) who underwent primary total ankle replacement. All patients received low-molecular-weight heparin prophylaxis. A total of 26 patients (3.9%, 26 ankles) had a symptomatic DVT, diagnosed by experienced radiologists using colour Doppler ultrasound. Most thrombi (22 patients, 84.6%) were localised distally in the operated limb. Using a logistic multiple regression model we identified obesity, a previous venous thromboembolic event and the absence of full post-operative weight-bearing as independent risk factors for developing a symptomatic DVT. The incidence of symptomatic DVT after total ankle replacement and use of low-molecular-weight heparin is comparable with that in patients undergoing total knee or hip replacement.

Prevention of VTE Following total hip and knee arthroplasty in Hemophilia patients

The often debilitating condition of hemophilic arthropathy is treated with elective total joint arthroplasty. Little has been published addressing the role of thromboembolic prophylaxis in the hemophilic patient population following total hip arthroplasty (THA) and total knee arthroplasty (TKA). Although the American College of Chest Physicians and the American Academy of Orthopaedic Surgeons have set guidelines for thromboembolic prophylaxis in the general population, no such standard of care is in place for hemophilic patients. While the risk of thrombosis in hemophilic patients following THA and TKA is thought to be lower, cases have been reported of pulmonary embolism and deep vein thrombosis (DVT) in hemophilic patients.