Cartilage Injury

knee-diagram-with-ligaments

Cartilage is the material which makes up the lining of joints such as the knee and hip, as well as forming the menisci, which are like rubbery ‘shock-absorbers’ positioned between the ends of the femur and tibia (thigh bone and shin bone).

Both types of cartilage can be damaged following an injury, often sustained during sporting activities. However, in many cases simply an awkward twist of the knee can cause damage. In addition to pain, swelling of the knee often develops over the first 24 hours, and movement may be restricted. If the knee remains persistently swollen, and particularly if the knee ‘locks up’ or ‘gives way’, urgent orthopaedic assessment is advised, as further damage to the joint may occur if the problem is left untreated.

Assessment involves a physical examination and usually an MRI scan. MRI has revolutionised the diagnostic accuracy following knee injuries, and is now an immediately accessible resource.

If MRI confirms a structural abnormality such as a meniscal tear or area of lining cartilage (‘chondral’) damage, then surgery may be recommended, usually in the form of arthroscopy (‘keyhole surgery’)

Cartilage repair techniques

In young patients (< 40 years old), it is sometimes possible to repair meniscal cartilage tears using keyhole surgery suturing techniques. This allows healing to take place and may help protect the knee joint from becoming arthritic in the future.

Arthroscopic meniscal repair

Arthroscopic meniscal repair

arthroscopic images of micro fracture technique

Arthroscopic images of microfracture technique

Arthroscopic techniques

Chondral (lining cartilage) damage can also be encouraged to heal using various arthroscopic techniques which encourage the natural repair process.

Abrasion chondroplasty and microfracture (see right) are two such techniques, which are effective in healing small cartilage defects in young patients.

Cartilage transplantation

Cartilage transplantation is a developing technique which involves harvesting some healthy cartilage from the knee, growing it in the laboratory and then re-implanting it some weeks later. Results suggest this may allow for more ‘natural’ cartilage repair, but further research on such techniques is still required.