First performed in 1960, hip replacement surgery is one of the most significant surgical advances of the last century. Constant improvements in joint replacement surgical techniques and technology have greatly increased the effectiveness of this surgery. Today, more than half a million total hip replacements are performed each year in the World. Similar surgical procedures are performed on other joints, including the knee, shoulder, ankle and elbow.
Normal Hip Joint: Before one tries to understand about hip replacement it is important to know about the normal hip joint. The hip is one of the body's largest weight-bearing joints. It consists of two main parts: a ball (femoral head) at the top of the thighbone (femur) that fits into a rounded socket (acetabulum) in the pelvis. Bands of tissue called ligaments (hip capsule) connect the ball to the socket and provide stability to the joint. The boney surfaces of this ball and socket have a smooth durable cover of articular cartilage that cushions the ends of the bones and allows them to move easily with little friction.A thin, smooth tissue called synovial membrane covers all remaining surfaces of the hip joint. This membrane secretes a fluid that lubricates and almost eliminates friction in the joint.
Conditions leading to the damage of Hip joint: The most common cause of chronic hip pain and disability is arthritis. It could be secondary to many different conditions like:
Avascular Necrosis of femoral Head: Avascular Necrosis (AVN) also known as aseptic necrosis or osteonecrosis is a disease of impaired blood flow to bone especially around joint. It commonly affects young people in 3rd to 5th decade. The commonest site of affection is the femoral head. It is a progressive disease which if left untreated leads to complete deterioration of the hip joint. The disease is an end condition that results from multiple causes. The list of causes is long and include alcohol abuse, systemic steroid use, sickle cell anemia, Gout, renal osteodystrophy, Gaucher’s disease and conditions associated with release of a blood clotting factor thromboplastin, like pregnancy, inflammatory bowel disease and malignant tumors.
Osteoarthritis usually occurs after age 50 and often in an individual with a family history of arthritis. It may be caused or accelerated by subtle irregularities in how the hip developed. In this form of the disease, the articular cartilage cushioning the bones of the hip wears away. The bones then rub against each other, causing hip pain and stiffness.
Rheumatoid Arthritis is an autoimmune disease in which the synovial membrane becomes inflamed, produces too much synovial fluid, and damages the articular cartilage, leading to pain and stiffness.
Traumatic Arthritis can follow a serious hip injury or fracture. A hip fracture can cause a condition known as avascular necrosis. The articular cartilage becomes damaged and, over time, causes hip pain and stiffness.
When to go for hip replacement?
Total hip replacement eliminates pain from the hip joint, as the damaged, articulating surfaces on the hip are replaced with smooth, artificial surfaces and is indicated when
- Hip pain limits your everyday activities such as walking or bending.
- Hip pain continues while resting, either day or night.
- Stiffness in a hip limits your ability to move or lift your leg.
- You have little pain relief from anti-inflammatory drugs or glucosamine sulfate.
- You have harmful or unpleasant side effects from your hip medications.
- Other treatments such as physical therapy or the use of a gait aid such as a cane don't relieve hip pain.
What happens during the procedure?
You will be given a general or spinal anesthetic. A general anesthetic will relax your muscles and cause a deep sleep. It will prevent you from feeling pain during the operation. A spinal anesthetic is a drug that will not cause you to sleep but should keep you from feeling pain during the operation.
The surgeon makes a cut along the side of your hip and moves the muscles atatched to the top of the femur (thighbone), and exposes the hip joint. The surgeon pulls the ball portion of the joint (the end of the femur) away from the socket part of the joint (the hipbone). The head (or ball) of the patient's femur and the neck of the femur (the thigh bone) are removed. An acetabular component is placed into the damaged socket. This component is a metal "cup" lined with a polyethylene shell (a hard plastic-like inner lining). The ball of the femoral implant (or stem) fits into this cup, creating a new, movable joint. The surgeon then reattaches the muscles to the top of the femur and closes the cut in the side of your hip.
The surgery lasts about two hours. You may be given a blood transfusion during the surgery. Two drains may be inserted to help drain any fluid or blood from the new joint. After surgery, you will be moved to the recovery room where you will remain for one to two hours while your recovery from anesthesia is monitored. After you awaken fully, you will be taken to your hospital room.
Types of Total Hip replacement:
Many different types of designs and materials are currently used in artificial hip joints. All of them consist of two basic components: the ball component (made of a highly polished strong metal or ceramic material) and the socket component (a durable cup of plastic, ceramic or metal, which may have an outer metal shell). Two basic types are available acemented variety and a non cemented variety and both of them offer effective pain relief. Your orthopaedic surgeon will choose the type of prosthesis that best meets your needs
In cemented type, special surgical cement is used to fill the gap between the prosthesis and remaining natural bone to secure the artificial joint.
A noncemented prosthesis has also been developed which is used most often in younger, more active patients with strong bone. The prosthesis may be coated with textured metal or a special bone-like substance, which allows bone to grow into the prosthesis (osseointegration).
A combination of the two - cemented ball and a noncemented socket may also be used.
Common Instructions after Discharge:
- Keep the skin clean and dry. The dressing applied in the hospital should not be changed without informing the doctor. If you have stitches that need to be removed, your surgeon will give you specific instructions about the incision and when you can bathe.
- Drugs: Take all medicines as directed by the surgeon. You will probably be given a blood thinner to prevent life-threatening clots from forming in the veins of your calf and thigh. It is especially important to prevent any bacterial infections from settling in your joint implant. You should get a medical alert card and take antibiotics whenever there is the possibility of a bacterial infection, such as when you have dental work.
- Diet: By the time you leave the hospital, you should be eating your normal diet. Your physician may recommend that you take iron and vitamin supplements. Continue to drink plenty of fluids – water and juices.
- Resuming normal activities: Once you get home, you should stay active. The key is not to do things over aggressively. One can expect some good days and some bad days, but one should notice a gradual improvement over time.
- Notify your doctor if the wound appears red or begins to drain.
- Take your temperature twice daily and notify your doctor if it exceeds 100.5°F.
- Swelling is normal for the first 3 to 6 months after surgery. Elevate your leg slightly and apply an ice pack for 15 to 20 minutes at a time, a few times a day.
- Calf pain, chest pain and shortness of breath are signs of a possible blood clot. Notify your doctor immediately if you notice any of these symptoms.
Precautions after a Hip Replacement
Do's and don'ts vary depending upon the surgeon's approach and implant used. The surgeon and the physiotherapist will provide you with a list of do's and don'ts to remember with your new hip. These precautions will help to prevent the new joint from dislocating and to ensure proper healing. Here are some of the most common precautions.
Don’ts
- Don't cross your legs at the knees for at least 8 weeks.
- Don't bring your knee up higher than your hip.
- Don't lean forward while sitting or as you sit down.
- Don't try to pick up something on the floor while you are sitting.
- Don't turn your feet excessively inward or outward when you bend down.
- Don't kneel on the knee on the Non- operated leg (the good side).
- Don't use pain as a guide for what you may or may not do.
- Don't reach down to pull up blankets when lying in bed.
- Don't bend at the waist beyond 90 degrees.
- Don't apply ice directly to the skin; use an ice pack or wrap it in a damp towel.
Do’s
- Do reduce your exercises if the muscles begin to pain, but don't stop doing them!
- Do keep the leg facing forward.
- Do keep the affected leg in front as you sit or stand.
- Do use a high kitchen or bar stool in the kitchen.
- Do kneel on the knee on the operated leg.
- Do use ice to reduce pain and swelling as ice will diminish pain sensation.
- Do apply heat before exercising to assist with range of motion. Use a heating pad or hot, damp towel for 15 to 20 minutes.