A retrospective review was done of the total joint registry at the Mayo Clinic, Rochester, Minnesota, which contains the computerized records of 19,808 consecutive total knee arthroplasties (TKAs) including primary and revision that were performed from 1970 to 1997. From that database, 9 patients were found to have had a TKA after an ipsilateral peripheral arterial reconstruction. One patient had had bilateral peripheral arterial reconstruction followed by bilateral TKA, and 10 TKAs were reviewed. The medical records were reviewed retrospectively with particular attention given to the type of peripheral bypass surgery performed, the bypass graft source, the timing of the bypass surgery relative to TKA, the use of a tourniquet at the time of TKA, and the occurrence of complications after TKA. Of the 10 TKAs, 2 patients had acute arterial occlusion. One patient had a tourniquet, and the other patient did not. There was not a statistical correlation between graft type, tourniquet use, timing of surgery, postoperative anticoagulation, and occurrence of arterial occlusion. There is a marked risk of acute thrombosis of an ipsilateral arterial bypass graft after TKA that cannot be eliminated by performing the TKA without a tourniquet. Careful monitoring of the vascular status of the limb is required in the early postoperative period to detect arterial compromise. Should limb ischemia be suspected, an emergent vascular surgery consultation is required, and arterial flow to the lower extremity must be re-established.