The geniculate arteries are five branches of the popliteal artery supplying the knee joint and its capsule. The superior lateral and superior medial geniculate arteries arise above the femoral condyles; the inferior lateral and inferior medial geniculate arteries arise below the tibial condyles; and the middle geniculate artery pierces the posterior capsule to supply the cruciate ligaments and synovium. Together they form the geniculate anastomosis with the descending genicular and recurrent tibial arteries.
The geniculate anastomosis provides critical collateral circulation around the knee. In popliteal artery occlusion from trauma or atherosclerosis, preservation of even one or two geniculate vessels can maintain distal limb viability through collateral flow. In total knee arthroplasty, the middle geniculate artery is routinely sacrificed during posterior capsulotomy; the geniculate anastomosis supplies the skin flaps. The superior geniculate arteries pass deep to the vastus medialis and lateralis origins and are at risk in extraperiosteal exposure of the distal femur.
In popliteal artery occlusion from posterior knee dislocation, preservation of geniculate collateral vessels determines whether the limb remains viable during the interval before revascularisation; an ABI above 0.9 with preserved collateral flow may allow short delay for arteriography, while absent collaterals demand immediate surgical revascularisation.
