The hip is a ball and socket joint that connects the thigh bone (femur) to the hip socket in the pelvis (acetabulum) to allow movement of the legs. The hip joint is the largest weight bearing joint in the body. The hip joint consists of the thigh bone and pelvis that are both covered in a smooth tissue called cartilage and separated by fluid to cushion the joint and allow smooth movement. The bones are held in the joint by ligaments, tendons and muscles.
When parts of the joint become diseased or damaged, it leads to pain and stiffness resulting in a loss of movement that affects the ability to undertake usual daily activities. A total hip replacement is a surgical procedure that may be a treatment option for:
- Arthritis of the hip
- Osteoarthritis – is the most common arthritis of the hip. It is caused by gradual wearing away of the cartilage in the hip joint that causes pain and swelling that results in a reduction of movement.
- Rheumatoid arthritis – an autoimmune disease that causes inflammation of the synovial membrane lining the joint resulting in cartilage damage and excess fluid being produced in the hip joint that leads to pain and swelling.
- Post traumatic arthritis – arthritis that may result following a fracture, dislocation or injury that causes pain and swelling.
- Avascular necrosis – a condition that results from a reduction in blood supply to the femoral head that causes bone death and results in the femoral head becoming misshapen.
- Conditions that affect hip development
- Congenital hip dysplasia – occurs when the hip joint forms abnormally during foetal development resulting in instability of the hip joint. If not detected and treated in infancy/early childhood, hip dysplasia can lead to hip dislocation and development of arthritis.
- Slipped Capital Femoral Epiphysis – is a hip condition that affects the growth plate in the head of thigh bone in adolescents. If left untreated it can lead to the development of arthritis.
- Perthe’s Disease – is a childhood condition that results from reduced blood flow to the femoral head that can lead to abnormality in the shape of the head of thigh bone which can lead to arthritis.
- Infection of the hip joint.
- Damage or disease of the connective tissue
A total hip replacement (THR) is a surgical option for patients with chronic hip conditions that can no longer be treated effectively with non-surgical treatment.
The procedure involves making an incision to expose the hip joint and removing the damaged bones and cartilage of this hip joint. The damaged parts are then replaced with a synthetic device (prosthesis) that mimics a healthy hip joint.
The prosthesis is made up of two parts:
- The femoral component replaces the femoral head (ball of the thighbone) with a metal stem that is inserted into the femur with a metal or ceramic ball on the top that will replace the femoral head.
- The acetabulum component replaces the damaged cartilage in the acetabulum (hip socket) with a metal socket which is held in place with screws or cement. A metal, plastic or ceramic cup is then placed in the new acetabulum that forms a lining to allow for a smooth gliding surface between the new femoral head and acetabulum.
When using this technology to assist with a hip replacement procedure, it aids in the accurate positioning of the implants which has been shown to correlate with improved function and lifespan of the hip prosthesis. The procedure can be performed through all current surgical approaches to the hip (muscle sparring direct anterior, posterior and lateral).
Your doctor will ask you questions to obtain information on your symptoms and medical history. A physical assessment will also be conducted to assess your level of hip movement and joint stiffness. If your doctor suspects your pain is caused by a hip condition, you will be referred for an x-ray. An MRI or CT scan may also be required.
A total hip replacement is generally only recommended once non-surgical treatment is no longer effective in managing your pain and inflammation, and you have increasing difficulty managing daily tasks.
Total hip replacement surgery can improve quality of life through the following benefits:
- Reduction or elimination of pain
- Increased mobility and movement
- Increases leg strength
- Enables you to sleep without pain
- Ability to return to normal activities
Total hip replacement surgery is one of the most successful orthopaedic procedures. However, as with any surgery there are associated risks. The general complications of any surgery include:
- Allergic reactions to medications
- Blood loss requiring transfusion
- Heart attack, strokes, kidney failure, pneumonia, bladder infections
- Complication from nerve blocks such as infection or nerve damage
The complications specific to hip surgery include:
- Deep vein thrombosis (blood clot)
- Damage to nerves or blood vessels
- Wound irritation
- Leg length inequality
- Failure to relieve pain
- Wear/loosening of the new joint
- Limited range of motion
- Heterotopic ossification (abnormal bone formation around the joint)
- Fractures of the femur or pelvis
Preparing for your total hip replacement
Preparation begins prior to your admission to hospital. Your surgeon will discuss your surgery and what to expect.
Arrangements should be made in advance to prepare for your recovery including:
- Ensuring your home is free from tripping hazards,
- Ensuring regularly used items are easily accessible,
- Arranging to have someone at home with you or to check in on you when you are discharged.
- A referral to the readmission service at the hospital you are having your surgery at can be very useful in helping you plan your discharge following your stay.
Your surgeon may refer you to have: routine blood tests and other investigations prior to your surgery. A rehabilitation physiotherapy review to ensure you are as fit as possible prior to your surgery.A review by a peri-operative physician, if you have medical problems that need to be managed around the time of your surgery.
You will be given instructions regarding your medications and it is important you follow these. These may include:
- Cease blood thinning medication such as aspirin and anti-inflammatory medications up to 7 days prior to your surgery
- Cease naturopathic or herbal medications 7 days prior to your surgery
Certain lifestyle risk factors can slow your healing following your surgery. In preparation for your recovery aim to:
- Eat healthy
- Quit smoking
- Reduce alcohol intake
- Reduce weight if overweight (follow medical advice on safe exercise prior to and following surgery)
Remember to bring your x-rays with you to hospital.
Following your surgery, you will usually remain in hospital for up to 5 days. In this time, you can expect to have a compression pump on your calves or feet to help prevent clotting (DVT). You will have ice regularly applied to your hip. Once your vital signs are stable and you have regained movement and sensation in your lower extremities, your physiotherapist will assist you to sit at the edge of the bed, stand and walk.
You will receive pain medication orally and if needed through your IV after surgery. You will also receive IV antibiotics, blood thinning medication to help prevent clots (DVT), and medication to help prevent nausea and constipation.
On discharge, you will be given an appointment to see your surgeon as an outpatient. You will also need to continue physiotherapy as instructed.
Post operation precautions
Your prosthetic hip must be treated with care. To avoid dislocation adhere to the following instructions:
- Avoid low chairs where your hips are lower than your knees. An elevated toilet seat is often required after hip surgery.
- Avoid bending to pick things up. Grabbers are helpful as are shoe horns or slip on shoes
- Sleep with a pillow between your legs for 6 weeks.
- Avoid crossing your legs and bending your hip past a right angle
- Sutures are usually dissolvable but if not will be removed 10-14 days after surgery.
- Your surgeon will give you advice about when it is okay to commence showering and bathing.
- Avoid applying creams or lotions to the wound once the wound unless directed by your surgeon.
- Hydrotherapy can commence once your surgeon is happy that your wound has healed (generally 4-6 weeks following surgery).
- If you are having procedures such as dental work or other surgery, you should consult your surgeon who may recommend you take antibiotics before and after your procedure to prevent infection in your new prosthesis. All non essential dental work should be avoided for 3 months following your joint replacement surgery.
- Driving can generally recommence 6 weeks following surgery
- Your new prosthesis may cause the metal detector to alarm at airports. A letter from your surgeon is generally not required prior to travel.
- Your surgeon will continue to follow your progress and how you and your new joint is functioning as time passes. Regular reviews and X-rays will be performed to ensure that you are performing well.