Overview of Meniscus Injuries
The meniscal cartilages of the knee are C-shaped shaped structures that help reduce the pressure between the bones and also absorb shock during weight-bearing.
There are two meniscal cartilages in the knee:
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The medial meniscus is on the inner aspect of the knee closest to the midline.
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The lateral meniscus is on the outer aspect of the knee away from the midline.
The menisci should be distinguished from the hyaline cartilage which is the clingfilm like shiny cartilage that lines and wraps the surfaces of the bones in order to reduce friction when the bones move against each other.
Meniscal tears
How do meniscal tears occur?
Meniscal tears can occur for two reasons:
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significant Injury to the knee, which often involves twisting and impact and can be associated with injuries to other structures such as the cruciate ligaments.
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A general weakening and thinning of the meniscus which can occur with with age or can be associated with chronic diseases such as diabetes or hypothyroidism. This weakening can then result in a small progressive tear to the meniscus which is not necessarily noticed at the time that it occurs.
In younger patients most meniscal tears involve significant injuries and are noticed at the time of injury.
What are the classic symptoms of meniscal tear?
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In the case of a single of injury, there may be a pain or pop at the time of injury. The knee can swell up either at the time of injury, or a few hours later.
There may be a period of recovery but then pain may occur when doing impact or twisting activities or deep kneeling.
Other symptoms can include:
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Catching of the knee when doing strenuous activities such as twisting,
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Locking of the knee which means that it freezes in one position and is difficult to fully straighten.
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Persistent swelling.
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Stiffness or reduction in straightening or bending of the knee.
How do we diagnose meniscus tears?
Most tears are diagnosed based on the patient’s story as well as the examination of the knee.
This is followed with an MRI scan which can confirm the diagnosis of the tear.
Treatment of tear
Treatment meniscus tears ranges from:
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Rest and physiotherapy and wait for the tear to scar up or heel.
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Early surgery.
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Late surgery for tears that are not healing or persistently symptomatic and painful.
At surgery the meniscus tear is assessed for how healthy the meniscus is, the location of the tear and the pattern of the tear.
There are certain locations of tear which can be stitched back to together to in order to save the meniscus.
Otherwise the torn meniscus portion may require removal.
The decision to whether to operate early, do physiotherapy and which operation to perform depends entirely on many factors:
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Age, health and activity level of the patient.
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How long symptoms have been present.
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Whether physiotherapy has already been tried and failed.
The decision to stitch or trim the tear again depends on;
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How long the tear has been present?
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The location of the tear:
(Tears in the red zone, which have a good blood supply and are in a line are generally more likely to heal and therefore amenable to being stitched.)
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The pattern of the tear and the state of the meniscal tissue at the time of surgery.
(For surgical treatment, Mr Gupte will use knee arthroscopy to either repair the meniscus or trim the torn portion if it cannot be repaired.)