Cartilage is the tough and flexible outer covering of bone found throughout the body. It serves many functions in the body:
- Act as a mould and shock absorber
- Reduces friction between bones
- Supports weight while movement
- Holds bones together
Types of cartilage:
Generally, there are three types of cartilage:
- Elastic cartilage
Elastic cartilage is the most flexible type of cartilage. It is mainly found in the outer region of ears, a part of nose, and epiglottis.
- Fibro cartilage
It is the strongest and toughest cartilage type. They have the ability to tolerate large weights. This type of cartilage is usually found between bones of pelvis and hips, and between spine discs.
- Hyaline cartilage (Articular Cartilage)
Hyaline or articular cartilage carries characteristics of both elastic and fibro cartilage. It is because hyaline cartilage is both strong and flexible. The areas where such cartilage occurs is between joints, near trachea, and in-between ribs.
A variety of causes exists for injury to cartilage:
- Dislocation in joint
- Damaged ligament or meniscus
- Direct collision or blow
- Less movement
The common symptoms of cartilage damage include:
- Swelling and stiffness
- Limited motion
- Locking of joint
A variety of tests such as MRI scan, X-ray and arthroscopy are done to diagnose damage in cartilage. The treatment includes both non-surgical and surgical method, depending upon the needs of the patient.
- Non-surgical Treatments:
The various non-surgical methods included are:
For initial 24-48 hours, the knee should be kept under crutches. Proper rest is essential for retaining physical strength.
Anti-inflammatory medications are useful in decreasing the effect of pain, inflammation and swelling throughout the body. Motrin, naproxyn, ibuprofen, and methylprednisolone. Heat and cold therapy may also be useful.
To suppress pain, application of injection directly on the affected part is advantageous. Commonly used injections are hyaluronic acid and corticosteroid injection. The hyaluronic acid mainly aims to reduce swelling or inflammation. They are also known as artificial joint fluid injections and act as knee lubricant. However, injections are not able to treat the underlying cause of symptoms. The effect of injections is temporary and normally remain only for 2-3 days.
Physical therapy or physiotherapy includes simple exercises which a patient is able to do without any strain or stress. They enable faster recovery and help to restore lost flexibility and mobility of body.
- Surgical Treatments:
For the patients who do not respond to any of the non-surgical treatments, surgery is necessary. The type of surgery depends upon the age, severity and activity level of patient. The commonly used surgical options include:
Debridement is a type of key hole arthroscopic surgery. In this method, small arthroscopic instruments such as mechanical shaver are inserted through the incision in the knee. These instruments are used to remove loose edges. Thus irritation or inflammation in the affected region is prevented. Stitches are used to smoothen the lesion.
- Marrow stimulation
In this procedure, tiny holes(micro fractures) are created under the damaged cartilage. This causes the exposure of blood vessels from the bone. As a result, a blood clot is formed inside the cartilage. These blood cells activate new cartilages. The only disadvantage of this method is that desired cartilage is not obtained.
The mosaicplasty method involves transplantation of cartilage from undamaged area to damaged area. It is important that the donor site should be a non-weight bearing part of the joint. This treatment is best for isolated cartilage damage areas of size in range 10-20mm. However, the treatment is not suitable for widespread cartilage damage.
- Autologous chondrocyte implantation (ACI)
In this procedure, a small sample of cartilage is taken from any part of the body. This sample is tested in a laboratory to develop a large number of cartilage cells. After about a period of 1-2 months, these cartilage cells are implanted on the knee. During surgery, a small segment of outer covering of bone is taken from the lower leg (periosteum). This covering is attached to the area of torn cartilage. The new cultivated cartilage cells are then injected into this region. Stitches are then used to close the perlosteum.
A one or two days stay in hospital after surgery is needed. Protective covering must be used to cover the joint surface. It is recommended to avoid putting weight on the operated part. For the first few weeks, the patient is usually put on crutches for proper movement. A rehabilitation program is the next step. It helps in restoring the mobility and flexibility of the affected part. In the initial stages, exercises for controlling the range of motion are used. Later, strengthening and stretching exercises will be employed. Complete recovery may take a few months.
Possible risks included in cartilage damage are:
- Difficulty in movement
- Severe and worsen pain
- Chances of occurrence of arthritis