Menisci are two crescent-shaped (half moon) discs between the thigh bone (femur) and the leg bone (tibia). They serve as shock absorbers and have several other important functions too.
How does the meniscus tear?
Meniscal lesions are commonly seen above the age of 40 and menisci can tear without significant injury. In rare instances when there is a developmental error (manufacturing defect !), the meniscus may be shaped like a disc instead of a half moon and it is then called a discoid meniscus. Such menisci are more prone to tear and may present as a painful or clicking or intermittently locked knee in children. Complex meniscal injuries are associated with cruciate or multiligament injuries and are addressed during the ligament reconstruction procedure.
Arthroscopic view of meniscus with a tear
Symptoms of meniscus tears
A meniscus tear usually presents with pain in the inner or outer aspect of knee. In some cases patients presents with locking of the knee.
Does my Meniscus tear require surgery?
Only meniscal tears that cause pain, limp, restricted movements or locking (unable to straighten the knee) require surgery. Occasionally, meniscal tears are associated with a cyst (commoner on the outer or lateral side). Meniscal surgery is generally a planned procedure however, in case of a "locked knee", early surgery is advised to prevent joint damage.
How is a torn meniscus managed?
Meniscus tears seen on MRI but not causing any symptoms are best left alone and do not need any intervention.
Meniscal tears that cause symptoms of pain, limp, localised painful swelling or locking, benefit from arthroscopic surgery which is of two types -
- Meniscectomy - the damaged portion of the meniscus is trimmed and the healthy portion preserved
- Meniscal repair - where the torn meniscus is stitched back using specialised techniques / implants.
Note : Not all meniscal tears can be repaired as the meniscus does not have optimum blood supply throughout its structure. Feasibility of repair is based on the time since injury, type & location of the tear (red or white zone of the meniscus) and whether it follows an injury or is degenerative in nature.
Can meniscal surgery be delayed?
Meniscal tears rarely heal on their own because of poor blood supply and with time, the tear often increases in size. Early intervention for symptomatic meniscal tears is therefore advisable