Most of us would know someone who is suffering from knee pain that is due to a torn meniscus. However, some will go for surgery, whilst others will be able to return to full function without it. What differentiates those two groups and why some are more “blessed” than others you may think?
To understand this, we need to know what the meniscus is. As shown in the picture, it is a semi-circular (C-shaped) structure that has a small degree of elasticity. Each knee has two meniscii, the outer known as lateral and the inner known as medial. These are weight-bearing and force-distributing structures and you can think of them as the cushions of the knee joint. About 50% of the forces are absorbed by them when the knee is straight, and 85% when the knee is at a right angle. Therefore, their importance in maintaining a healthy knee is achieved by three main functions:
- Load transmission
- Shock Absorption
- Joint nutrition
The burden of a torn meniscus:
Depending on the type of tear as well as associated injuries, meniscus lesions result in pain on the inner or outer surface of the knee and may include the following signs:
- Locking of the knee
- Catching pain
- Feeling of stiffness/fullness of the joint
The pain is especially aggravated with sudden rotations and can be a disabling causing you to limit your normal activities of daily life.
Long-term, disability may be due to the development of osteoarthritis due to friction caused either by a fragment of the meniscus or due to loading of the joint.
Osteoarthritis management is discussed in a previous newsletter which you can find using this link.
However, why would some tears need surgery whilst others do not?
The meniscii unfortunately have poor blood supply, with only the periphery receiving 10%-30% and this becomes less cellular with age.
The two categories, traumatic and degenerative, must be distinguished because of the fundamental differences in optimal management.
The first occurs with trauma usually from a sudden rotation (pivoting injury) of the knee, especially with high velocity. The second may have a gradual onset as part of the normal degeneration of the structures in the body due to the ageing process.
With a traumatic meniscal tear most commonly, the treatment involves surgery followed by physiotherapy rehabilitation in order for you to regain back the mobility, strength and stability of the joint and return to normal activities of daily life.
For the degenerative meniscal lesions, research is supporting conservative management with physiotherapy and exercise and avoiding surgery due to its high rate of success. Your experienced physiotherapist will be able to prescribe an appropriate exercise program as well as use different modalities to help alleviate your pain.
The prevalence of meniscus lesions in general population:
- Age 50-59 years old ≈ 25%
- 60-69 years old ≈ 35%
- 70-79 years old ≈ 45%
- Patients with knee osteoarthritis 75-95%
The downside of surgery comes from potential complications. These can include infections, chronic pain, stiffness and others. However, the greater downside comes from a particular type of surgery called the meniscectomy, meaning that the meniscus is removed. This has been associated with the development of arthrosis causing flattening of the joint and osteophyte development. Even in cases of partial meniscectomy, there is 65% increase in pressure, however, it is necessary in some cases. This is especially important for traumatic tears or degenerative tears that cannot be managed conservatively and would increase the chances of joint degeneration if left untreated.
The decision will be made by you when considering the suggestion of your surgeon and clearly understanding the positives and negatives of surgery.
What can we do together to reduce pain?
1. Losing weight
- Regaining range of movement
- Improving the strength and stability of the joint
- Initially avoiding aggravating activities
- Gradually returning to normal participation as the joint allows us
Take home message
I always like to base everything I do on research BUT most importantly the applicability in real life. I have seen patients suffering and struggling to manage their symptoms of meniscus tears due to ignorance or potentially wrong beliefs about the pathology. Please keep in mind that:
- Meniscal tears have a great success rate conservatively or post-surgery.
- The decision should be carefully made discussing all the positives and negatives of each decision with your consultant.
- Don’t delay seeking medical and healthcare advice as outcomes are great