Deep vein thrombosis after lower limb amputation

The purpose of this study is to prospectively document the incidence of deep vein thrombosis (DVT) in the residual limb after a below-knee amputation.

Eight of 13 male patients, admitted to the acute rehabilitation floor after a below-knee amputation, were included in the study. Patients already receiving anticoagulants were excluded. An investigator questioned the patient regarding the patient's risk factors for DVT and history of DVT and pulmonary embolus. A coagulation profile was obtained for all patients. A Doppler ultrasound was completed on the residual limb 2 wk after amputation, and if negative, it was repeated 2 wk later. Patients found to have a DVT were treated appropriately. The incidence of DVT was calculated by a point estimate, and a 95% confidence interval was calculated using simple large sample methods.

Four of the eight patients had ultrasound evidence of DVT in the thigh. Two of the four patients had signs or symptoms of a DVT. There were a comparable number of risk factors for DVT in both groups. Laboratory values were not statistically significant in predicting the occurrence of DVT, probably because of the limited number of subjects.

The present study supports the assumption that the diagnosis of lower limb DVT is frequently associated with lower limb amputation. However, a larger sample may be necessary to conclude that a routine screening ultrasound of the lower limbs is indicated after a below-knee amputation.