What is the meniscus?
The meniscus is a type of cartilage that lies within the knee joint. It’s primary role is shock absorption. It sits between the condyles of your tibia and interacts with the articular surface of the femur. There are 2 menisci within the knee joint, the lateral and a medial. In addition to shock absorption, the meniscus increases the stability of femorotibial articulation, distributes load evenly throughout the hinge joint of the knee and provides lubrication for smooth range of movement.
How can the meniscus be injured?
Traumatic (acute): injuries are most commonly caused by twisting on a bent knee whilst in weight-bearing. These types of injuries often happen during activities that include rapid direction change and in high-contact sports such as; Rugby, AFL, Soccer, Netball etc.
Non-traumatic (chronic): these types of injuries occur after minimal amounts of trauma over a long period.
Different types of meniscus ruptures:
- Intra substance/Incomplete tear
- Horizontal/transverse tear
- Radial tear
- Flap tear
- Bucket-handle tear
- Complex tear
How do you diagnose an injury to the meniscus?
Diagnosis of a meniscal tear/injury involves a thorough patient assessment and subjective history. Your Physiotherapist or treating Physician will investigate the mechanism of injury; twisting/loading, weight-bearing status post-injury, return to play capacity, location and pain. Some common signs and symptoms include:
- Tenderness around the joint line
- Swelling locally or around the knee
- Pain with twisting
- Pain with bending or deep knee flexion activities like squatting
- Locking or catching of the knee as it goes through its range of motion
- Positive special tests for meniscus as mentioned above
Special tests are used as part of the objective assessment to aid the diagnosis of a meniscal tear. The following tests may be used:
- McMurray’s
- Apley’s test
- Joint line tenderness
- Thessaly’s test
Risk factors for meniscal injuries
Degenerative:
- Age > 60 years
- Male gender
- Work related kneeling or squatting
- Climbing stairs
Acute:
- Playing soccer and rugby
- Male gender
- > 12 months delayed ACL reconstruction increases medial meniscus injury risk
What can Physiotherapy do to help?
For a traumatic injury, the first point of treatment includes the RICER method (Rest, Ice, Compression, Elevation and Referral for imaging and/or specialist). A review with your Physiotherapist post injury is recommended within the first 14 days. Physiotherapists can diagnose, assess the severity of the injury, refer for diagnostic imaging and instigate referral pathways for orthopaedic review.
In acute or degenerative meniscal injuries, Physiotherapy provides education for healing, self-management strategies, activity modification advice and an individualised mobility and strengthening program. Working with your Physician, you and your treating team will determine the appropriateness of surgical intervention based on age, function, activity levels and goals. There is strong evidence that physical strengthening plays an important role in reducing pain, improving joint stiffness, muscle strength and ability in meniscal tears.
When does surgery become an option?
Surgery is considered an option when an injury is causing severe pain, limiting activities of daily life and when the knee range is locking or very limited. Meniscectomy, meniscal repair, and meniscal reconstruction are now the three main surgical techniques for treating meniscus injuries. An arthroscope is also another technique performed to clean out the knee joint of any loose fragments within the knee that have potentially torn off from the menisci which can cause the knee to lock and catch.
References:
- Snoeker BAM, Bakker EWP, Kegel CAT, Lucas C. Risk factors for Meniscal Tears: A systematic review including meta-analysis. Journal of Orthopaedic & Sports Physical Therapy. 2013;43(6):352-367. doi:10.2519/jospt.2013.4295