Meniscal pathology

One of most common injuries to the knee joint involves damage to the one of the meniscal tissues. The knee joint has a medial (U-shaped) and lateral (S-shaped) meniscus which is made up of various materials to be recognized as a type of fibrocartilage. While these tissues absorb shock and help with load bearing forces while increasing the bony fit of the knee joint, each meniscus also assists protecting, lubricating and allowing for nutrition of the underlying articular cartilage. Hence, the most vital function of the meniscal tissues is to prevent damage to the articular cartilage and early onset of osteoarthritis. Most of the meniscal tears occur at the “posterior horn” region at the medial meniscus.

However, due to the lack of blood supply of the inner part of each meniscus, the opportunity for healing remains limited to the outer aspect.

The types of meniscal tears can be defined as:

• bucket handle or vertical-longitudinal (usually associated with acute, traumatic tears)
• flat/oblique
• radial/transverse
• horizontal/complex (usually associated with degenerative meniscal tears)

Usually, meniscal injuries occur in two types of mechanisms of injury which correspond with two different age groups.

Typically, an acute, “sharp”, traumatic injury to the meniscus involves a younger person (under 30 years old) engaged in a sports-related activity when their foot remains planted in the ground as they could feel a “pop” during a twisting, cutting or rotational motion. 

On the other hand, the other group consists of middle-aged to elderly individuals who are > 60 years old, but do not seem to have any particular cause of discomfort. However, these persons could have a greater amount of kneeling or squatting and excessive stair climbing as their injury stems more from a degenerative condition. This older group tends to have more symptoms associated with osteoarthritis than the meniscal lesion.

However, in both cases, the meniscal lesion can cause the person to experience a variety of symptoms such as swelling, limited motion, tenderness at the joint line and a “popping” sensation. Furthermore, individuals with meniscal tears could complain of catching, locking, buckling or giving way symptoms.

In the examination, a high likelihood of damage to the meniscus involve having:

• Mechanism of injury (traumatic vs insidious onset)
• Swelling
• Tenderness to palpation on the joint line (inside/medial joint line or outside/lateral joint line)
• Discomfort with limited motion during flexion or extension
• Positive meniscal testing such as the McMurray’s

Treatment of meniscal injuries usually initiate with conservative management with the P.R.I.C.E. formula (Protection, Rest, Ice, Compression, Elevation) and engaging in physical therapy to reduce the swelling, advance the knee mobility-ROM, increase muscular control (especially of the quadriceps) and progressing to more functional activities as dictated by response to conservative care.

Here are some suggested exercises to attempt but these exercises should be relatively pain-free. However, as always, consult with your physician prior to initiating an exercise program (disclaimer). Disclaimer: This program provides exercises related to your condition that you can perform at home. As there is a risk of injury with any activity, use caution when performing exercises. If you experience any pain or discomfort, discontinue the exercises and contact your health care provider.

At Home Meniscal Exercises

Current literature suggests participating in 3-6 months of conservative care prior to surgical intervention as the orthopedic surgeon “should strive not to operate in most cases, but to protect, repair or reconstruct, in order to prevent early development of osteoarthritis by restoring the native structure, function, and biomechanics of the meniscus.” (Doral et al).

If symptoms continue to persist, surgical options can be used as it ranges from partial menisectomy (debridement and cleaning of the meniscus), meniscal repair (techniques designed to suture tear) or meniscal reconstruction (advanced surgical procedures such as allograft transplant).

 

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https://link.springer.com/chapter/10.1007/978-1-4471-6572-9_79 meniscal images

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