Arthroplasty

Arthroplasty literally means 'formation of joint'. It refers to the surgical replacement of arthritic or destructive joint with prosthesis. During arthroplasty, the dysfunctional joint is replaced with a better remodeled joint. Osteotomy procedure used to restore or modify joint congruity is also arthroplasty. Although arthroplasty is used for construction of a new movable joint, it cannot be applied to every body joint. Its use, in practice, is confined to the shoulder, elbow, hip, knee, certain joints of the hand, metatarso-phalangeal joints in the foot.

The two main reasons for undergoing arthroplasty are pain in the joints and decreased quality of life. Some common indications for arthroplasty would include advanced osteoarthritis, rheumatoid arthritis with avascular necrosis, congenital dislocation of the hip joint, shallow hip socket, frozen shoulder, loose shoulder, traumatized joint and joint stiffness, un united fractures of the neck of the femur, and for correction of certain types of deformity.

There are three methods in general which are adopted in Arthroplasty: excision arthroplasty, half-joint replacement arthroplasty and total replacement arthroplasty. Each of these methods have their own distinct merits as well as disadvantages and special applications.

In excision arthroplasty both the articular ends of the bones are simply excised. A gap is created between them and this is filled with fibrous tissue, a pad of muscle or other soft tissue which may be sewn in between the bones. This method is applicable to all the joints other than the knee and ankle.

In half-joint replacement arthroplasty, one of the articulating surfaces is removed and this is replaced by a prosthesis of similar shape. The prosthesis is made of metal and rarely silicone rubber. This technique has its application at the hip. It has rather limited use elsewhere in the body.

As for total replacement arthroplasty, both the opposed articulating surfaces are excised and replaced by prosthetic components. Sometimes, in larger joints, one of the components is of metal and the other, a high density polyethylene. Both components are held in place by acrylic 'cement.'

The joint is fully exposed and the damaged bone and cartilage are cut away or reshaped. Prosthesis are inserted after measurements are taken to ensure proper fit. The joints are usually tested before the incision is closed. Arthroplasty is typically followed by several days of hospitalization. Medications are given to relieve the pain and prevent further infections and blood clots. Physical therapy is extensively employed to bring back the joints to near normal functioning. Occupational therapy is also prescribed to enable patient independently cope up with routine activities. Patients resume normal activities after two to three months duration.