Background Venous thromboembolism (VTE) [i.e., pulmonary embolism (PE) and deep vein thrombosis (DVT)] is a common complication during and after a hospital admission. Further, VTE is a leading cause of major complications and death after major orthopedic surgery. To avoid the development of VTE after orthopedic surgery, it is essential to reduce the onset of deep vein thrombosis (DVT) and to diagnose DVT early. It leads to early diagnosis to find a risk factor of DVT from medical history of the patient. Total knee arthroplasty (TKA) reliably relieves pain and improves function in patients with end-stage arthropathy of the knee such as osteoarthritis (OA) and rheumatoid arthritis (RA). The most common complication after knee arthroplasty is DVT. However, the risk for preoperative DVT in patients for knee joint orthopedic surgery remains unclear. Therefore, we investigated the patient's background and medical history in patients admitted to hospital for primary TKA, and identified the risk factors for DVT development before TKA.
Objectives The objectives are investigated the risk factors of DVT in patients admitted for primary TKA.
Methods Patients. From 2003 to 2013, 303 patients admitted for primary TKA at Mie University Hospital were eligible for the present retrospective study. The patients' sex, weight, body mass index (BMI, weight in kilograms divided by the square of the height in meters), and data from the medical history and medical condition were recorded.
Diagnosis of DVT. B-mode ultrasonography with compression and color Doppler imaging were performed for bilateral common femoral veins, the superficial veins, the popliteal veins, and the calf veins.
Statistical analysis. The patients' preoperative characteristics were compared between the DVT-positive and DVT-negative patients using the Mann-Whitney U test and Fisher's exact test. Multiple linear regression analysis was performed to identify independent risk factors for preoperative DVT. P values <0.05 were considered statistically significant.
Results The preoperative diagnosis was OA in 261 patients (86.1%) and RA in 42 patients. The most frequent preoperative medical history or medical condition was hypertension (52.1%). The second most frequent preoperative medical history or medical condition was major surgery (47.5%).
Preoperative DVT was diagnosed in 48 of 303 (15.8%) patients overall. Significantly elevated risks of DVT were found in patients who had RA (p<0.05) using Fisher's exact test. Multiple linear regression analysis was performed to test the association of DVT with putative risk factors. The analysis showed that admission for RA (p<0.05) were significant independent risk factors for preoperative DVT.
Conclusions A high prevalence (15.8%) of preoperative asymptomatic DVT was found in patients admitted for primary TKA. In this study, RA was risk factors for preoperative DVT among those admitted to the hospital for primary TKA.
Disclosure of Interest None declared