The elbow joint is where the different bones connect and allows motion. It is a hinge joint made up of three bones:
1. The humerus (upper arm bone)
2. The ulna (forearm bone on the pinky finger side)
3. The radius (forearm bone on the thumb side)
The surface of the bones where they connect and form the elbow joint are covered with cartilage that enables the flexibility and easy movement of the hand. Synovial membrane covers all remaining surface inside the elbow joint and makes a small amount of fluid which lubricates the cartilage and removes any friction in the arm while moving or rotating. Elbow joint is held together with muscles, ligaments and tendons.
In total elbow replacement surgery, a surgeon replaces the diseased elbow with an artificial joint made from two implants that attaches to the bone in the arm. Implant is joined together with the help of a metal and plastic hinge. It is quite similar to the hip and knee replacement procedure. There are different types of elbow replacement used in particular situations. This is a complicated procedure as the elbow has several moving parts that balance each other to control the forearm movement.
The elbow can get damaged due to bad injury or diseases such as:
• Rheumatoid arthritis – also known as inflammatory arthritis, is a connective tissue disorder in which the synovial membrane surrounding the joint becomes inflamed and thickened leading to destructive changes of the joint. The chronic inflammation can damage the cartilage gradually causing the cartilage loss, pain and stiffness. Other joints such as the hands and shoulders are also usually involved.
• Osteoarthritis – degenerative joint disease usually occurs in people of 50 years or above. The cartilage of the elbow bones soften and wear away. The bones rub against one another making the elbow joint stiff and painful.
• Badly fractured bone in the upper or lower arm near the elbow – in case of shattered elbow, it may be difficult for doctor to put the pieces back in place and blood supply to the bones are interrupted.
• Damaged or torn tissues in the elbow.
• Tumor in the elbow
The damage can be surgically repaired in some cases but if the damage is serious and extensive then the doctor may suggest elbow replacement surgery.
Depending on the problem, a patient may need a replacement of just one portion of the joint. For example, if only the head of one of the forearm bones is damaged, it can be replaced with an artificial head. There are mainly two types of prosthetic devices:
• Linked – this type of prosthesis acts like a loose hinge as all the parts of the replacement joints are connected and provide good joint stability.
• Unlinked – this device comes in two separate pieces not connected to each other. This design depends on the nearby ligaments to hold the joint together making it more prone to dislocation.
There can be some potential risk or complications that may involve:
• Implant problem
• Nerve injury and damage to blood vessels
• Loosening or dislocation of the artificial parts
• Tendons weakness or failure
• Reaction to medicines
• Blood clots or bleeding
• Bone broken during the surgery
Before the surgery, patient should let the doctor know about his/her medical history, medications, and conditions including allergies, diseases like heart problem or diabetes, if he/she smokes or drinks. Elbow replacement surgery can take about 2 hours. Patient will be given general anesthesia that puts the patient to sleep. Surgeon will make an incision at the back of the elbow and gently move the muscle aside to reach the bone. Surgeon will then remove the scar tissue and prepares the humerus to fit the metallic piece to replace that side of the joint. Same procedure is done for the ulna. These replaced stems are kept in a place with bone cement. The two stems are connected by a hinge pin. Padded dressing will be placed after the wound is closed and splint will keep it stable. Patient may feel pain or discomfort after the surgery.
Patient may need to stay at the hospital for 3-4 days post surgery. Doctor may suggest some pain medicines, antibiotics to prevent any infection and some simple exercise or other types of physical therapy to help the arm get stronger and functional. The complete recovery can take up to a year and patient will not be allowed to lift heavy weight. It may need some time to get used to the new elbow.