The menisci are cartilaginous structures in the knee that reduce friction during movement and disperse the weight of the body. Within the knee, there are two types of menisci, known as the lateral and medial meniscus, respectively. They are susceptible to injury, especially during contact sports such as football and soccer. There are a variety of symptoms of a torn meniscus.
Knee Pain
The most common symptom that is reported by victims of a meniscal tear is pain, especially upon movement. One of the diagnostic signs is pain in the injured knee while rolling over during sleep. This is known as Cooper's Sign. Deep-knee bending also elicits considerable pain. Tenderness along the lateral or posterior part of the knee when pressure is applied is also highly suggestive of a meniscal tear.
Knee Swelling
Knee swelling typically occurs about a day after the injury as the tear causes local irritation within the joint space. In addition, a collection (known as effusion) of blood can also develop in the knee. This is especially common if the peripheral portions of the meniscus are torn as they contain the highest quantity of blood vessels.
Joint Locking
Patients with a tear of the menisci often complain of a feeling that the joint "locks" in place. This often first occurs within the first day after the injury. One possible mechanism of joint locking is contraction of the hamstrings due to knee instability. Often, a torn piece of meniscus floats into the joint, causing further slipping or locking of the joint.
References
- "Clinics in Sports Medicine;" Rehabilitation of the Knee Following Sports Injury; De Carlo, M et al. Volume 29, January 2010
- "DeLee and Drez's Orthopaedic Sports Medicine, 3rd Edition;" DeLee; 2009
- "Essentials of Physical Medicine and Rehabilitation, 2nd Edition;" Frontera; 2008
