Meniscal Injury
Meniscal injuries are acutely painful right at the time of injury. The most common sources of pain consist of the distortion of the joint capsule or synovitis from the meniscal injury. The studies report that there is a presence of nociceptor fibers in the anterior and posterior horns along with in the outer vascular layer (the red zone). This shows that there is an additional pain source which causes discomfort of the injuries in the avascular inner layer (white zone). Meniscal injuries are similar to ACL injuries in terms of causing long lasting degenerative changes. A meniscal injury results in volume loss and a higher risk of degenerative change.