This prospective study was performed on 311 consecutive knees in 227 patients for total knee arthroplasty. The aim was to assess the recent incidence of deep vein thrombosis (DVT) after total knee arthroplasty without chemoprophylaxis in Koreans, the efficacy of plasma d-dimer levels as a screening test, and the associated risk factors. Deep vein thrombosis was found in 79 knees (26.60%). There were 9 cases (3.03%) of proximal DVT, 70 cases (23.57%) of distal DVT, and no symptomatic pulmonary embolism. Although this cohort had limited number of patients by a single surgeon, there is still low incidence of proximal DVT in Koreans with rare pulmonary embolism occurrence compared with those of the Western. High postoperative d-dimer levels were correlative, but no appropriate cutoff value was found. Obesity was a significant associated risk factor.
In patients undergoing major orthopedic surgery, data of deep venous thrombosis (DVT) and pulmonary embolism (PE) are lacking as studied by computed tomographic (CT) pulmonary angiography and indirect CT venography (CTPA-CTV). A prospective observational study was performed for 363 Korean patients undergoing major orthopedic surgery to determine the incidence of venous thromboembolism (VTE), especially proximal DVT and PE. The incidence of VTE was 16.3% (n=59). Of them, 8 patients (2.2%) were symptomatic. The rate of VTE was the highest in patients who underwent total knee replacement (40.4%), followed by hip fracture surgery (16.4%), and total hip replacement (8.7%; P<0.001). The incidence of PE was 6.6% (n=24). Of them, 4 patients (1.1%) were symptomatic. Forty-one patients (11.3%) were in the proximal DVT or PE group. Based on multivariate analysis, total knee replacement and age > or =65 yr were significant risk factors for proximal DVT or PE in patients undergoing major orthopedic surgery (odds ratio [OR], 2.4; 95% confidence interval [CI], 1.1-5.1; P=0.025; and OR, 2.1; 95% CI, 1.0-4.4; P=0.046, respectively). Taken together, the overall incidence of PE was 6.6% and rate of symptomatic PE rate was 1.1%. Knee joint replacement and age > or =65 yr were significant risk factors for proximal DVT or PE.
PURPOSE: To compare the efficacy and safety of different modes of thromboembolic prophylaxis for elective total knee arthroplasty (TKA) in Asian patients. METHODS: 440 low-risk patients undergoing TKA were randomised into 4 equal groups: (1) no prophylaxis (control), (2) graduated compression stockings (GCS), (3) intermittent pneumatic compression (IPC), and (4) low-molecular-weight heparin (enoxaparin). Duplex ultrasonography was used as an assessment tool. RESULTS: The deep vein thrombosis point prevalence was highest in the control group (22%), which was significantly higher than in patients receiving IPC (8%, p=0.032) or enoxaparin (6%, p=0.001). One patient each in the control and GCS groups developed a non-fatal pulmonary embolism. Patients on enoxaparin received more blood transfusions and 2 of them had major bleeding complications. CONCLUSION: IPC is the preferred method of thromboprophylaxis for TKA in Asian patients.
BACKGROUND: Enoxaparin is a low-molecular-weight heparin indicated in Europe and North America for the prevention of venous thromboembolism (VTE) in patients undergoing major orthopedic surgery. Registration trials of enoxaparin have been conducted primarily in Caucasian populations, and the efficacy and safety of enoxaparin in Japanese patients have not been demonstrated. We evaluated three dosage regimens of postoperative enoxaparin in Japanese patients undergoing elective total hip or knee arthroplasty.
METHODS: Two multicenter, randomized, double-blind studies enrolled 436 and 396 Japanese adults undergoing total hip or knee arthroplasty, respectively. The dosage regimens of enoxaparin were 20 mg once daily (qd), 40 mg qd, 20 mg twice daily (bid), or placebo for 14 consecutive days. The primary efficacy endpoint was the incidence of VTE in the modified intention-to-treat (mITT) population up to 15 days after surgery. VTE was defined as a composite of deep vein thrombosis (determined by venography) and symptomatic pulmonary embolism (confirmed by appropriate objective methods). Patients were also followed up at 90 days for VTE events. The primary safety outcome was the incidence of any bleeding during treatment and the follow-up period.
RESULTS: In the mITT populations, the incidence of VTE was 41.9% and 60.8% in the placebo groups after hip or knee arthroplasty, respectively, 25.9% and 44.9% in the enoxaparin 20 mg qd groups, 33.8% and 35.1% in the enoxaparin 40 mg qd groups, and 20.0% and 29.8% in the enoxaparin 20 mg bid groups. Only enoxaparin 20 mg bid significantly lowered the risk of VTE relative to placebo (by 52.2% and 51.0% after hip and knee arthroplasty, respectively). At the 90-day follow-up, no further cases of VTE were reported. In both the hip and knee studies, the four treatment groups did not differ significantly regarding the incidence of patients with any bleeding.
CONCLUSIONS: Our findings support the use of enoxaparin (20 mg bid daily, commencing 24-36 h postoperatively) in Japanese patients undergoing total hip or knee arthroplasty.
BACKGROUND AND PURPOSE: The relationship of D-dimer and deep-vein thrombosis (DVT) after total knee arthroplasty (TKA) remains controversial. The purpose of this study was to assess the value of D-dimer in the detection of early DVT after TKA.
METHODS: The measurements of plasma D-dimer level were obtained preoperatively and at day 7 postoperatively in 78 patients undergoing TKA. Ascending venography was performed in 7 to 10 days after surgery. The plasma D-dimer levels were correlated statistically with the venographic DVT.
RESULTS: Venographic DVT was identified in 40% of patients. High plasma D-dimer level >2.0 mug/ml was found in 68% of patients with DVT and 45% without DVT (P < 0.05). Therefore, high D-dimer level greater than 2.0 mug/ml showed 68% sensitivity, 55% specificity, 60% accuracy, 50% positive predictive rate and 72% negative predictive rate in the detection of early DVT after TKA.
CONCLUSION: High plasma D-dimer level is a moderately sensitive, but less specific marker in the detection of early of DVT after TKA. Measurement of serum D-dimer alone is not accurate enough to detect DVT after TKA. Venography is recommended in patients with elevated D-dimer and clinically suspected but asymptomatic DVT after TKA.
BACKGROUND: Venous thromboembolism (VTE) is a common and potential serious complication in lower extremity surgeries, especially in hip and knee arthroplasty. Pulmonary embolism is one of the most fatal complications. The recognition of VTE in the lower limb has been considered as an indication for anticoagulation. Many studies have shown that thrombophilia is one factor of VTE and the most common causes are protein C, protein S and antithrombin III deficiency, factor V leiden and dysfibrinogenemia. VTE is a disease of Western populations because of well documentation of incidence and many studies about thrombophilia. In Thailand, the prevalence of VTE has been unclear.
OBJECTIVE: The present prospective study evaluated the prevalence of thrombophilia and venous thromboembolism after total knee arthroplasty in patients who did not receive prophylactic treatment of VTE in Phramongkutklao Hospital.
STUDY DESIGN: Descriptive prospective consecutive case studies.
SETTING: The Department of Orthopedic Surgery, Phramongkutklao Hospital, Bangkok Thailand.
MATERIAL AND METHOD: Blood sample was examined at 2-3 weeks before TKA for measuring the level of thrombophilia. Bilateral ascending contrast venography of the lower extremities was performed routinely between 6th-10th post operative days after total knee arthroplasty.
RESULTS: The authors studied 100 patients, 94 primary TKA and 6 revisions TKA. Sixty-one (61%) were positive for deep vein thrombosis. Eleven patients with positive venograms showed bilateral DVT twelve (12%) had a proximal DVT one was protein C deficiency, nine were protein S deficiency, 18 were antithrombin III deficiency, and 36 were positive study for FDP(D-dimer), However, no one was found with factor V leiden. Odds ratio of protein S deficiency was 0.9506, Antithrombin III deficiency was 0.7376, and FDP(D-dimer) was 1.229. The protein C deficiency and factor V leiden was undetermined.
CONCLUSION: Patients who have total knee arthroplasty performed are at high risk for deep venous thrombosis. Although fetal pulmonary embolism rarely occurs in Thai populations, mechanical prevention was routinely used and prophylactic regimen should be a part of management of patients who undergo total knee arthroplasty.
BACKGROUND: The definition of gastrocneumus and soleus deep-vein thrombosis (DVT) remains controversial. The purpose of this study was to evaluate the clinical significance of muscular deep-vein thrombosis after total knee arthroplasty (TKA).
METHODS: This study consisted of 359 consecutive patients undergoing TKA evaluated for DVT by ascending venography. Venographies were performed 5 to 7 days after surgery. Those patients showing positive DVT underwent a follow-up venographic study at 3 months. The evaluation parameters included clinical symptoms, late DVT, thrombus propagation and pulmonary embolism. The data from patients with isolated muscular DVT were compared statistically with those patients with DVT of the leg veins and combined DVT.
RESULTS: Of 359 patients, 175 (49%) developed venographic DVT including 160 with distal and 15 with proximal DVT. Of the 160 cases with distal DVT, 83 (52%) involved the gastroneumus and soleus muscular veins. Of these 83 cases, 38 (46%) were isolated muscular DVT and 45 (54%) involved muscular branches and major leg veins including the anterior and posterior tibial and peroneal veins. Patients with isolated muscular DVT showed comparable rates of clinical symptoms, late DVT, thrombus propagation and no pulmonary embolism compared with patients with DVT in the major leg veins (p = 0.874, 0.398 and 1.000) and patients with combined DVT (p = 0.155, 0.592 and 1.000).
CONCLUSION: The clinical significance of isolated muscular DVT is comparable to that of the major leg veins and combined DVT. Muscular DVT in the calf is considered a significant clinical entity and should be treated accordingly.
We evaluated a total of 473 knees (264 patients) to determine the prevalence of deep vein thrombosis and pulmonary embolism (PE) in those who were not given thromboprophylaxis after total knee arthroplasty (TKA). Deep vein thrombosis was diagnosed by roentgenographic venography, and PE was diagnosed by perfusion lung scanning. In patients with bilateral TKA, 47 (11%) of 418 venograms showed positive findings for thrombi, whereas in patients with unilateral TKA, 11 (20%) of 55 venograms showed positive findings for thrombi (P = .758). No patient had symptoms of PE, and findings for the perfusion lung scans were negative in all patients. We neither treat our patients for deep vein thrombosis and PE prophylactically nor therapeutically unless patient has a symptomatic PE.
BACKGROUND: A prospective clinical study was performed to compare the efficacy of low-molecular-weight heparin and indomethacin for the prevention of deep-vein thrombosis after total knee arthroplasty in Asian patients.
METHODS: One hundred and fifty patients undergoing total knee arthroplasty were randomly divided into three groups. One group consisted of fifty-one patients who received no prophylaxis with an anticoagulant (the control group), one consisted of fifty patients who received the low-molecular-weight heparin Fraxiparine (the Fraxiparine group), and the third consisted of forty-nine patients who received indomethacin (the indomethacin group). Bilateral ascending venography was performed preoperatively and at five, six, or seven days postoperatively. A third venogram was made at three months for patients who had had a deep-vein thrombosis.
RESULTS: The prevalence of deep-vein thrombosis was 71% in the control group, 50% in the Fraxiparine group (p = 0.042), and 45% in the indomethacin group (p = 0.011). Only 28% of the deep-vein thromboses were symptomatic, and there were no pulmonary emboli.
CONCLUSIONS: Compared with no prophylaxis, Fraxiparine and indomethacin significantly lowered the prevalence of deep-vein thrombosis after total knee arthroplasty. Prophylaxis against deep-vein thrombosis in the Asian population appears to be warranted.
LEVEL OF EVIDENCE: Therapeutic study, Level I-1a (randomized controlled trial [significant difference]). See Instructions to Authors for a complete description of levels of evidence.
BACKGROUND: Deep vein thrombosis (DVT) is one of the most common complications of total hip (THA) and total knee arthroplasty (TKA). Though the reported incidence of DVT is very high, that of proximal DVT is low and that of fatal thromboembolism is very low. Hence the issue of prophylaxis for DVT remains controversial. The incidence of DVT is based on various studies in European and American populations. The Asian population is genetically and socially quite different from American and European populations, and the incidence of DVT can be quite different. Therefore a prospective study was initiated at our centre to determine incidence of DVT after THA and TKA in Indian patients.
METHODS: A prospective study was conducted on 60 hips in 45 patients and 46 knees in 26 patients who underwent THA and TKA respectively, without any known risk factors for thromboembolic disease. DVT was studied by preoperative and postoperative serial colour Doppler ultrasonography. No prophylaxis was given to any of the patients.
RESULTS: DVT was found in two patients who had undergone THA. No case of DVT was detected in any patient who had undergone TKA.
CONCLUSION: These results suggest that the incidence of DVT in Indian patients is very low and is not comparable with American and European populations. It is therefore not cost effective to advise prophylaxis in Indian patients undergoing THA/TKA who have no known risk factors for DVT.
This prospective study was performed on 311 consecutive knees in 227 patients for total knee arthroplasty. The aim was to assess the recent incidence of deep vein thrombosis (DVT) after total knee arthroplasty without chemoprophylaxis in Koreans, the efficacy of plasma d-dimer levels as a screening test, and the associated risk factors. Deep vein thrombosis was found in 79 knees (26.60%). There were 9 cases (3.03%) of proximal DVT, 70 cases (23.57%) of distal DVT, and no symptomatic pulmonary embolism. Although this cohort had limited number of patients by a single surgeon, there is still low incidence of proximal DVT in Koreans with rare pulmonary embolism occurrence compared with those of the Western. High postoperative d-dimer levels were correlative, but no appropriate cutoff value was found. Obesity was a significant associated risk factor.
