The genicular arteries are a group of small arteries that supply blood to the knee joint. There are four genicular arteries: the superior lateral genicular artery, the superior medial genicular artery, the inferior lateral genicular artery, and the inferior medial genicular artery.
The superior lateral genicular artery and the superior medial genicular artery arise from the popliteal artery, which is the main artery of the knee. These arteries supply blood to the upper portion of the knee joint and to the muscles and tissues that surround it.
The inferior lateral genicular artery and the inferior medial genicular artery arise from the anterior tibial artery and the posterior tibial artery, respectively. These arteries supply blood to the lower portion of the knee joint and to the bones and ligaments that support it.
In addition to supplying blood to the knee joint, the genicular arteries also play an important role in the innervation of the knee. They provide blood to the genicular nerves, which are responsible for transmitting pain signals from the knee to the brain. As such, the genicular arteries are a key target in genicular artery embolization, a procedure used to treat chronic knee pain.
Classification systems have been proposed for this anatomy. For more information a great review article can be found at: https://www.jvir.org/article/S1051-0443(21)01585-2/fulltext