Neural and vascular anatomy of the menisci of the human knee

Study Design: Review of literature. Objectives: To review the general anatomy, vascular anatomy, healing potential, neural anatomy, and sensory functions of the menisci of the human knee. Background: Recent research has revealed important roles and functions of the menisci of the human knee. Methods and Measures: A Medline search was performed using the following title and key words: menisci, meniscus, meniscal, vascular blood, neural, nerve, anatomy, healing, sensory, mechanoreceptors, proprioception, nociceptors, surgery, meniscectomy, repair, and rehabilitation. The references from each article obtained were then reviewed in order to find additional articles not already located through the Medline search. Results: In adults, the blood supply to the menisci of the knee reaches the outer 10% to 33% of the body of the menisci. This portion of the menisci is capable of inflammation, repair, and remodeling. Neural innervation with nociceptors and type I, II, and III mechanoreceptors reaches the outer 66% of the body of the menisci. The anterior and posterior horns of the menisci have a rich supply of both blood vessels and nerves. Conclusions: The menisci of the human knee are an important source of proprioceptive information regarding the position, direction, velocity, and acceleration and deceleration of the knee. Rehabilitation following injury or surgery to the menisci of the knee should, therefore, incorporate a proprioceptive retraining program that respects both the abilities and inabilities of different portions of the menisci to follow through with repair and remodeling.