Menisci are rubbery, C-shaped discs found in the knee. There are two menisci in each knee which lie in between the thigh (femur) and shin (tibia) bones. The meniscus on the inside of the knee is the medial meniscus, and the meniscus on the outside of the knee is the lateral meniscus. The job of the menisci is to assist in nourishing the knee joint, to provide cushioning for force absorption and to provide stability.
The medial meniscus is less mobile and carries more pressure during weight-bearing so is more commonly injured than the lateral meniscus. Meniscal tears can be caused by a traumatic injury or can be degenerative i.e., age-related. Meniscus injuries can also be associated with other ligament injuries (typically the ACL and MCL).
Injury
A tear of a meniscus can be caused by:
- Twisting or turning quickly when the knee is bent and under load
- A blow to a bent or twisted knee
- Degenerative processes in the older population
What do I feel?
- Pain when bending or loading the knee (eg squatting, kneeling, jumping etc)
- Swelling/tenderness around the knee
- A popping or clicking may be felt within the knee
- The knee may lock or catch with movement
What can I do?
- Apply ice to the knee for pain relief for 20mins every 2hrs for the first 48-72hrs
- Elevation – prop the leg up on pillows
- Rest from activity
- Apply compression to the knee joint area
- Take pain relief medication as directed on the label or by your doctor/pharmacist
- See a physiotherapist for effective rehabilitation and exercises
The outside 1/3 of the meniscus has a rich blood supply, therefore, tears in this zone have the potential to heal on their own. In contrast, the inner 2/3 of the meniscus lacks blood supply and without nutrients from blood, tears in this inner zone cannot heal. The severity of meniscal tears depends on tear length, tear depth, tear pattern and tear location.
Treatment for a minor tear may be managed conservatively through physiotherapy and can take 6-8 weeks to resolve. Rehabilitation usually involves restoring range of movement, stretching and strengthening of the muscles surrounding the knee joint, and balance/coordination exercises. Early use of low or non-weight-bearing exercises such as hydrotherapy and/or cycling on a stationary bike are recommended. More severe and complex tears may take 3-6 months to resolve (depending on an individual’s physical requirements) or may require arthroscopic surgery. A rehabilitation programme, similar to the treatment for a minor tear, will be implemented following surgery. Degenerative tears are usually treated conservatively with physiotherapy and anti-inflammatory pain medication