Hip replacement surgery is a surgical procedure that is done to replace a damaged or worn-out natural hip joint with a prosthesis. In this surgery, few segments of the femur (thigh bone) and acetabulum (socket of hip bone) are removed and replaced with an artificial hip joint.
Types of hip replacement surgery
There are many variants of hip replacement surgery. Some of these variants are mentioned are as follow:
- In a total hip replacement, the whole hip joint (ball and socket) is removed and replaced with an artificial hip joint. The artificial ball attached on top of a stem is fitted into the socket of the hip joint and the stem is inserted into the femur. Also, a socket is fitted into the natural socket part of the hip bone.
- In a partial hip replacement(hemiarthroplasty), only the femoral head (ball at the top of the femur) is taken out and an artificial ball is put in its place and its stem is inserted into the thigh bone. The socket is left intact.
- In the hip resurfacing procedure, the damage from the natural hip bone head is trimmed and it is resurfaced with a metal casing. A metal lining is also fitted into the natural hip bone socket.
- Simultaneous (Bilateral) hip replacement: Simultaneous hip replacement is indicated when both hips require replacement. This kind of surgery can be done at the same time or it can be performed in two stages (Staged hip replacement). In a Staged hip replacement, one hip joint is replaced, and the patient is allowed to recover and after recovery from one surgery, a similar surgery is performed on the second hip joint.
Indications for hip replacement surgery
A hip replacement may be considered and performed to enhance the patient’s ability to move, alleviate pain and increase the range of motion of the affected joint.
If the patient has moderate to severe arthritis (inflammation of the joint) and it has been confirmed through tests. Some of the most common kinds of arthritis are mentioned below:
- Osteoarthritis: This type of arthritis is the ‘wear and tear type’. It manifests in people aged 50 or above and there is a family history of arthritis in these patients.
- Rheumatoid arthritis: It is an autoimmune disease. It is the most common arthritis in a group of disorders called ‘inflammatory arthritis’.
- Post-traumatic arthritis: Post Traumatic arthritis develops after a fracture or an injury.
If the hip joint is necrosed. (It has been damaged due to impaired blood supply).
If the patient has moderate to severe pain and it is interfering with day-to-day activities climbing stairs, getting in and out of the chair, and putting on socks.
If there is a limited range of motion and stiffness because of joint degeneration.
If the symptoms do not improve with pain medication or physical therapy.
Common types of implants
For hip replacement surgery, there are many variants of hip implants and they differ primarily in the material of their parts and size. Usually, hip implants are made of metal, plastic (polyethylene), ceramic, or a combination of these materials.
Metal on polyethylene: They are among the most common materials being used. A metal ball and a plastic socket are used in this implant. There is a risk of the development of osteolysis due to wear debris.
Metal on Metal: They are no longer available due to the risk of metallosis (metal poisoning).
Ceramic on polyethylene: In this type of implant, there is a ceramic ball and plastic socket. Osteolysis can occur in this type of implant because of the wear and presence of plastic.
Ceramic on ceramic: This implant has a ceramic ball fitted within a ceramic socket. Loosening of the lining or the hip component fractures leads to failures of these joints.
Benefits of the hip replacement
A high rate of success: Total hip replacement is one of the most successful surgical procedures in the medical field.
Pain relief: Total hip replacement offers a dramatic reduction in hip pain with complete or near-complete improvement in pain.
Better hip function: One of the major benefits is a significant enhancement in hip joint functionality. One will be able to walk without any support and perform daily tasks like climbing stairs, putting on socks, and getting up from a chair without any pain.
A long-lasting solution: Hip replacement surgery is a long-term solution. Most of the implants are still functional after 20 years.
Complications and risks
There are always complications and risks associated with any surgical procedure. The majority of patients who have had their hip replaced do not go through any major complications. Some will face minor issues and occasionally, a few will have serious complications.
After hip replacement surgery, the most common complications are dislocation, failure of the implant, blood clots, infection, and impaired nerve function.
Infection: A person can have a superficial infection of the surgical wound or a deep infection of the implant. The superficial infection can be readily treated with antibiotics. In deep infection, surgical washout may be required, and hip revision surgery may be indicated in severe cases.
Joint loosening: It is a rare complication. It can be fixed with further surgery.
Dislocation: It is more likely in the first month after surgery. A dislocated hip will have to be put in place again and may require surgery.
Fracture: The fracture of thigh bone or acetabulum can occur if rehabilitation is done quickly and vigorously. The treatment can involve surgery in severe cases. It is best to limit stress on one’s hip or knees to let the body heal.
Uneven leg length: Post hip replacement surgery, one leg may feel longer or shorter than the other leg. The surgeon may lengthen or shorten your leg to maximize stability and biomechanics of the hip joint.
Nerve function abnormality: Numb patch, painful neuroma, or paralysis of muscles due to damage of nerves during surgery can occur in various circumstances.
DVT and pulmonary embolism: There is a risk of developing blood clots during or after any surgery and this risk is enhanced in joint replacement procedures. DVT is deep vein thrombosis. A pulmonary embolism occurs when a blood clot dislodges from a vein and enters the lungs. This requires extensive treatment and can be life-threatening. Blood-thinning medications and early mobilization can help prevent the development of blood clots.
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2. Orthoinfo, Total hip replacement, Accessed 17 March 2021, https://orthoinfo.aaos.org/en/treatment/total-hip-replacement/
3. Hospital for special surgery, Hip replacement, Accessed 17 March 2021, https://www.hss.edu/condition-list_hip-replacement.asp
4. Drugwatch, Hip replacement, Accessed 17 March 2021, https://www.drugwatch.com/hip-replacement/
5. Arthritis-health, Indications and eligibility for total hip replacement surgery, Accessed 17 March 2021, https://www.arthritis-health.com/surgery/hip-surgery/indications-and-eligibility-total-hip-replacement-surgery