Unlabelled: Isolated popliteal artery is defined as an obstruction of a superficial femoral artery with a patent popliteal segment followed by an obstructed distal popliteal artery or a patent leg artery less than 5 cm long., Purpose: The aim of this retrospective study was to report the results of surgical treatment and the causes of failures., Patients and Methods: From 1988 to 1996, 31 patients with isolated popliteal artery were operated on with femoropopliteal bypass. The age of the patients ranged from 45 to 92 years, (mean: 79 years); all had critical ischemia that threatened limb viability. All underwent preoperative arteriography and diagnosis was confirmed by intraoperative arteriography., Results: In the postoperative course, there were 22 patent bypasses (68%) with minor amputation in five patients, and nine thromboses that required a major amputation in seven patients, a trans-metatarsal amputation in one, and a medical treatment in one. With a mean 37-month follow-up, seven thromboses required a major amputation in five patients, a new bypass in one and a medical treatment in one. The death rate was 34% at two years. The actuarial patency rates of the bypasses were 51% at one year, 38% at two years and 25% at five years. The limb salvage rate was identical. The patency rates were 65% at one, two and five years for venous bypasses and 38%, 13% and 0% respectively for PTFE bypasses. Statistical analysis showed two causes of failure: the absence of a run-off branch and the use of PTFE prostheses. No other statistically significant cause of failure was demonstrated among those analysed. Favourable anatomic conditions for a bypass to a leg artery were not predictive of failure of a femoro-popliteal bypass on the isolated arterial segment., Conclusion: Bypass to isolated popliteal artery is indicated in patients whose limb viability is jeopardized. Results may be considered as satisfactory especially if there is a run-off branch and if a venous graft is available for the bypass.