What is a Total Hip Joint Replacement? – Blog By Christian Bonello
A Total Hip Replacement (THJR) is one of the most common operations in orthopaedic surgery. It is a surgical procedure whereby the diseased hip joint is replaced with an artificial prosthesis. As the hip is classified as a ball-and-socket joint; the ‘socket’ is formed by the acetabulum, which is part of the pelvis bone, and the ‘ball’ is the head of the femur or thigh bone. The bone surfaces of the ball and socket are covered with articular cartilage which cushions the joint and enables smooth movement. Overtime the joint may become degenerated causing reduced movement and increased pain especially in activities such as walking.
A THR is therefore performed to relieve pain of degenerative diseases affecting the hip joint. The procedure is performed by replacing the diseased head of the femoral (thigh) bone with a metal stem that is placed into the hollow center of the femur. The femoral stem may be either cemented or “press fit” into the bone. A metal or ceramic ball is then placed on the upper part of the stem and this ball replaces the damaged femoral head that was removed. The damaged cartilage surface of the socket (acetabulum) is removed and replaced with a metal socket. Screws or cement are sometimes used to hold the socket in place. A plastic, ceramic, or metal spacer is then inserted between the new ball and the socket to allow for a smooth gliding surface.
Type of Incisions
Depending on the patients age, fitness level, hip presentation and the orthopaedic surgeon’s preference; two incisions are commonly utilised for patients undergoing a Total Hip Replacement:
- Posterolateral approach: Incision is made via the rear and side of the hip joint. Due to the muscles that are separated, limitations of hip movement are advised in the first six weeks following surgery. These include keeping the height of the knee below that of the hip, no twisting the lower limb inwards and no bringing the leg past the middle of the body. Special equipment such as an over-the-toilet chair, higher chair and a pick-up stick are usually recommended during the first six weeks following surgery.
- Anterior approach: the incision is made through the front of the thigh and offers a potential for an accelerated recovery time as key muscles are not detached during the operation.
Who requires a hip replacement?
A total hip replacement is considered for patients whose hip joints have been severely damaged by either progressive arthritis, trauma or other joint pathology.
- The most common type of arthritis occurs where there is gradual loss of articular cartilage causing bone remodelling, joint inflammation and loss of normal joint function. It mainly affects people over the age of 50 and usually affects people with family history of osteoarthritis and may cause significant pain.
- Rheumatoid Arthritis: This autoimmune condition involves chemical changes in the synovial membrane surrounding the joint (within the capsule), causing it to become thick and inflamed. This causes the breakdown of the cartilage and joint degeneration over-time.
- Post-Traumatic Arthritis: Trauma to the hip joint either via serious hip injury or fracture can cause the bone and the cartilage to not heal correctly. This can mean that the hip joint may develop arthritis. Alternatively a THR may be the intervention of choice for orthopaedic surgeons managing a hip fracture in older populations.
- Avascular necrosis:An injury to the hip, such as a dislocation or fracture, may limit the blood supply to the femoral head. The lack of blood may cause cell death to the bone tissue resulting in tiny bone breaks and the bones eventual collapse. Some diseases can also cause avascular necrosis.
- Childhood hip diseases: Some infants and children are born with hip pathology. Even though many of these conditions are successfully treated during childhood, they may cause arthritis later on in life if the hip joint does not grow in optimal alignment and the joint surfaces are affected.
How can I prepare for Surgery?
It is recommended prior to your surgery that you attend a physiotherapy class where you will be taught a series of exercises that will help to strengthen the muscles in your legs. To physically prepare for the surgery you will be given a home exercise program designed by a physiotherapist or exercise physiologist. This will focus on increasing the strength of the muscles in your legs, your abdominal muscles and your arms. This improved strength will help you to mobilise more easily following your surgery. The physiotherapy information will also help you to know what will be expected of you after your surgery.
Reduce alcohol intake
It is always recommended that you decrease your alcohol intake prior to surgery. Some of the drugs given to you either during or after your operation can interact with any alcohol that is in your system.
Lose Weight (for patients who are overweight)
By losing weight prior to your surgery, it will help reduce the stress on your new hip joint and help you mobilise more freely. Being over-weight can increase your risks of a raised blood pressure and therefore complicate your post-operative period.
Cigarette smoking has been proven to increase the time it takes you and your joint to heal. It’s a good idea to stop smoking at any stage, but this is a perfect opportunity.
Rehabilitation exercises following a Total Hip Replacement will start on the evening of or the day following your procedure depending on the surgeon’s protocol. This will be guided by your physiotherapist and will include hip range of motion exercises, muscle activation and strengthening exercises and early mobilisation. Following a Total Hip Replacement, you can usually put as much weight on the knee as you feel comfortable, however this will be guided by your surgeon.
If a rehabilitation hospital is not required, it is recommended to start outpatient (private) physiotherapy a week following discharge from hospital and arriving home. This will incorporate manual therapy and progression of exercises to optimise the outcome of surgery. If required, hydrotherapy may also be of benefit during this period.
It is essential during this time to manage both the normal post-operative responses – such and swelling, joint stiffness, bleeding and muscular tension – at the same time as you push to improve muscular strength and joint range of motion. Finding the right balance with the aid of your physiotherapist will ensure an optimal post-operative outcome.
It may take up to 12 months to experience a full recovery from THJR surgery. Our team expect that you graduate from 1:1 physiotherapy into a self-managed exercise routine or group class during your rehabilitation. It is vital to maintain half an hour of daily exercise throughout your life and return to activities that are important to you. Ideally such exercises should incorporate a mix of aerobic exercise that elevate your heart rate and strength-based training.
At Total Physiocare we are responsible for the orthopaedic care of patients at both Warringal Private and Western Private Hospital. We also offer pre-habilitation exercise programs with our team of physiotherapists or exercise physiologist and hydrotherapy services to assist in the recovery plan following a Total Hip Replacement.
Post by Christian Bonello (Physiotherapist)