Introduction: Types and Risks of Rheumatoid Arthritis Surgery
The surgery for replacing joints has been perfected over the years and although a last resort to alleviate pain, it has brought relief to many sufferers of rheumatoid arthritis.
Most joints can be replaced nowadays from the tiny knuckle joint in the finger to the main weight-bearing hip joint.
This is an article on rheumatoid arthritis and in particular replacing a rheumatic joint with an artificial one.
The article centers on an examination of the procedures, common types of replacement joints and, the risks involved in rheumatoid arthritis surgery.
Procedures and Types of Joints that can be Replaced by Surgery; the Goals and Risks
The goals of any replacement joint surgery is to reduce the pain and increase the mobility of the person suffering from R/A, enabling them to live a normal life again.
The most common joints being replaced are total hip, knee, shoulder and elbow joints; these are examined below along with the risks.
1. Total Hip Replacement
Hip joints are the most common joint being replaced by surgeons today. The hip joint is a ball and socket joint and the surgeon will cut the old ball part of the joint away, drilling a hole down the femur.
On the replacement hip joint, the ball is on the end of a stem, usually made of an inert metal such as stainless steel or titanium and this stem is inserted into the hole in the femur. Epoxy glue is then injected between the stem and the femur, which cures very quickly giving a secure fit.
The old socket is then cleaned up and a new “plastic” socket glued into its place in the pelvis.
The ball and socket are then fitted together and the wound sewn up.
The risks following a total hip replacement are as follows:
This is a very serious condition as if infection occurs in the joint following surgery, there is every likely-hood that the joint will have to be surgically removed and the patient bedridden until the infection is cleared up.
The infected joint will have “slime” on the surface, which is dangerous to treat with antibiotics, so only after removal of the replacement joint can antibiotics be taken to kill the infection.
Following this the surgeon may decide to carry out another joint replacement, or immobilize or “freeze” the joint.
This is not common, some sources quote that 10% of replacement joints dislocate. The main method for preventing this is to exercise the joint (see my article on hip replacement exercises and precautions) and do not cross one’s legs and sleep on one’s back with a pillow between the knees.
Dislocation can be extremely painful and medical assistance should be obtained.
As with all anesthetics there is a risk of heart or respiratory problems occurring whilst the patient is “under”. However modern methods have eradicated most of these by having a pre-operation examination, where the patients breathing and heart function is monitored and recorded.
2. Total Knee Replacement
The knee joint works like a hinge and the replacement comes in two parts; the upper hinge and the bottom bearing pad.
The knee joint is completely removed by the surgeon, apart from the patella (knee cap) which if not affected with R/A, is usually left in place, connected by a tendon to the thigh muscles.
A hole is drilled into the femur (thigh bone) and the stem of the top joint, which resembles an anchor shape, is inserted into the femur and glued in place.
A hole is then drilled into the tibia (shin bone) and the stem of the bottom joint inserted into the hole and glued. The bottom joint is in the shape of an anvil, with a sliding surface which the top joint moves against. The knee cap is then refitted and the wound stitched.
Extensive physiotherapy follows to tighten muscles and tendons (see my article on knee exercises). The knee joint is held in place by four large ligaments which prevent it dislocating or the bones moving in the wrong direction.
Risks are as per hip replacement, except for dislocation which is very rare and usually only occurs after a fall or car accident.
Reference Web: Knee Replacement
3. Total Shoulder Replacement
The shoulder is a ball and socket joint procedure and is much the same as the hip joint. In a shoulder joint, the socket is in the shoulder, the ball being in the humerus (upper arm). Replacing this joint entails the ball on the humerus being cut away and the humerus drilled to accept the stem of the new ball which is glued in place. If the socket in the shoulder is badly worn, this will be replaced by a new plastic socket, also being glued in place. However, it is usual to leave the socket in place if it is unaffected by R/A, with only the ball being replaced.
When the glue has hardened, the ball and socket are manipulated and fitted together, and then the wound is sewn up.
Mobilization is quite quick with the patient up and about doing some arm swinging exercises, with the arm being kept in a sling for some time after the operation.
Where conventional replacement has not been successful, a procedure known as reverse shoulder replacement can be used. Here the two components are swapped over; the socket being on a long stem and fitted to humerus, with the ball attached to the shoulder bone.
Risks are dislocation, infection and analgesia as per the total hip replacement risks, and although pain has been reduced, movement is still restricted.
Reference Web: Shoulder Replacement
4. Total Elbow Joint Replacement
The elbow joint is a hinge type, and connects the humerus to two other forearm bones known as the radius and ulna.
Total replacement consists of inserting and gluing the stem of one part of the joint into a hole drilled into the humerus, the other one being inserted into ulna, which also has been drilled to accept the stem. The special shaped heads have a lining of plastic to allow low friction movement.
Once the glue had hardened, a steel pin is inserted through the head of each joint forming a hinge.
Risks are rejection of the joints by the body as it is quite a complicated procedure as a lot of metal is used along with much “bone machining”. Infection can occur for the same reason, and as always there is the risk that although the pain is gone, the elbow movement may be still restricted.
Reference Web: Elbow replacement