DEEP VEIN THROMBOSIS FOLLOWING LOWER LIMB ARTHROPLASTY: PREVALENCE AND CORRELATION TO PATIENT-PERCEIVED FUNCTIONAL OUTCOME AT ONE YEAR

Abstract

Deep venous thrombosis (DVT) and clinical outcome measurements in a series of 610 patients who did not receive routine chemical thromboprophylaxis for lower limb arthroplasty were studied. Patients who had undergone primary total hip or knee replacement under the care of two orthopaedic consultants were identified from the Trent Arthroplasty Database. Surgery was performed between 1992 and 1999 in one hospital only. Venography was undertaken on the seventh to tenth postoperative day. Patients with proximal thrombosis were anti-coagulated with warfarin as per protocol. Venogram reports were available for 81% of cases.

One year following surgery a standard postal questionnaire was sent to all patients. A response rate of 88% was achieved. Data was captured with respect to residual pain, ability to walk and the overall satisfaction with joint replacement.

DVT following total hip (THR) or knee replacement (TKR) in patients who did not receive routine chemical thromboprophylaxis was common (46. 4%) in line with other studies.

Knee surgery was associated with a high prevalence of thrombosis (57. 6%) compared to hip replacement although only one fifth of DVTs were found to extend into a proximal vein. Approximately half (44. 2%) of all THR associated thrombus was above knee DVT. Questionnaire responses evaluating clinical outcome and satisfaction were correlated to venographic results and analysed using an SPSS statistical package. Using Chi-squared analysis no statistically significant differences were found between deep venous thrombosis and patient-perceived pain (p=0. 12), mobility (p=0. 07) or overall satisfaction (p=0. 23). It is generally assumed that chemical thromboprophylaxis will diminish DVT related complications such as post-phlebitic limb syndrome. Despite a high prevalence of thrombosis in patients who did not receive pharmacological agents for prophylaxis, this study did not demonstrate an adverse outcome on pain, function or patient satisfaction. Morbidity as a result of DVT needs to be studied further before the role of chemical thromboprophylaxis can be determined.