Hip Replacement

The hip is a ball-and-socket joint. The ball is formed by the top of the thigh bone (femoral head) and the socket is formed by the bony pelvis (acetabulum). The joint is lined by hyaline cartilage, which is smooth and allows for frictionless movement. Degeneration of hyaline cartilage results in osteoarthritis, with increasing friction between the bones resulting in pain and stiffness. Hip replacement is most commonly performed for hip osteoarthritis, but can also be used to treat rheumatoid arthritis, osteonecrosis, or a hip fracture.

During the surgery, the damaged bony ball and socket are removed and new components are inserted. The replacement components are made of metal or ceramic, with a plastic (polyethylene) liner placed between the ball and socket to allow for safe, frictionless movement. Depending on your age and the quality of your bone, either a cemented or cementless component will be used. The surgical incision is closed using stitches, and dressings are put on your skin. Once you are asleep, surgery generally takes around an hour to perform.

Various types of approaches can be used to access the hip joint, and some have theoretical advantages over others. In general, I prefer approaches which minimise the number of muscles which need to be moved to access the hip joint to aid in a rapid post-operative recovery.

Hip replacement: Before surgery

My assistant will help you through the booking process and will be able to give you a quote for your surgical fees at this time.

General health

In most cases, you should continue with any regular prescribed medications in the lead-up to your surgery. Please let me know if you:

• Have bleeding disorders or previous problems with blood clots in the legs or lungs
• Are taking any blood thinners
• Have diabetes, a heart condition or a lung condition
• Have had previous joint infections
• Are smoking: Smoking is associated with slower wound healing, which increases your risk of infection.

It is a good idea to remain as active as possible leading up to your surgery. If possible, low-impact activity should be continued.

Hip replacement: Anaesthesia

Hip joint replacement can be performed under general or spinal anaesthesia. My assistant will give you the details of my anaesthetist at the time of your surgical booking. They will contact you prior to surgery to discuss the plan for your anaesthesia, and risks that may be specific to you.

Hip replacement: Day of surgery

You will be admitted to hospital on the day of surgery. You will be advised of your admission time in the days leading up to your surgery.

Hip replacement: Inpatient stay

Your hospital stay will generally range from 1 to 5 days. Occasionally patients will require transfer to the rehabilitation ward of the hospital for a more prolonged stay. If required, we can arrange this during your hospital admission. A physiotherapist will visit you twice per day while in hospital. It is important to also perform your prescribed exercises and activities on your own to enhance recovery. Once discharged, I recommend you see a physiotherapist regularly until you have recovered to a satisfactory level. I can help you with referrals to local physiotherapists. If you already have an existing relationship with a physiotherapist then you may also return to their care.

Hip replacement: Follow up

First 2 weeks

The goals in the first 2 weeks after surgery are to:

• Increase your comfort level with your new hip
• Decrease swelling
• Regain function of your leg muscles
• Walk on your new hip with the aid of crutches or a frame.

I will review you in the rooms approximately 2 weeks after surgery. If you are unsure of your follow-up appointment time, please call my assistant.

First 3 months

The aim is to improve function and comfort levels by:

• Reducing the need for crutches and frames
• Increasing muscle strength
• Engaging in hydrotherapy and stationary cycling.

3-12 months

There is gradual improvement in hip function, where the benefits gained on a day-to-day basis will be less noticeable. Complete recovery often takes 12 months.

Hip replacement: Wound care

Overlying the surgical incision is an adhesive dressing, which can remain in place if clean and dry. I will check the healing of your wound at our follow-up appointment approximately 2 weeks after surgery.

Hip replacement: Pain relief

There are many options for pain relief, and my anaesthetist will discuss these with you. Once discharged from hospital, you will have pain relief medication that you can take to help with your comfort levels. Initially, patients require some regular pain relief, consisting of regular paracetamol and anti-inflammatories if indicated. For periods of increased pain during the day (breakthrough pain), you will be prescribed a faster acting pain medication to take. Some of these pain relievers can have side effects such as nausea, stomach upset or sedation. Doses can be tailored to try and reduce these side effects and to keep you as comfortable as possible. It might be necessary to avoid certain activities (e.g. driving) if you are prescribed stronger pain medication.

Hip replacement: Driving

The exact time until you return to driving varies depending on your recovery and the leg that has been operated on. The Australian Orthopaedic Association (AOA) recommends at least 6 weeks after surgery before you consider recommencing driving.

Hip replacement: Return to work

At a bare minimum, you should have 2 weeks off to allow the incision to heal and your mobility to improve. Most patients will require more than 2 weeks off work.

Hip replacement: Dental work

Any planned dental work or current dental problems should be dealt with before your hip replacement. If you have dental work at any time after your hip replacement, let your dentist or surgeon know that you’ve had joint surgery. The dentist may opt to prescribe you antibiotics to prevent infections that can spread from the mouth to the hip joint replacement via the bloodstream.

Hip replacement: Problems

Deep infection
The risk of joint replacement infection is about 1%. This may occur at any time after surgery, as infection can spread to your hip from another part of your body. In the event you do have a joint infection, it is important to seek treatment as soon as possible. Oral antibiotics will not treat this problem and you will require surgery to wash the hip joint out. Occasionally those with resistant infections will require surgery where the existing hip replacement is removed and a new replacement inserted after a period of antibiotics (revision hip replacement).

If you are concerned about an infection, please contact me as soon as possible. During business hours the best point of contact is via my assistant on 08 9212 4292. After hours, please contact the hospital where you had your surgery, and ask them to get in touch with me. Failing this, go to your local Emergency Department for review.

Superficial infection
This is usually an infection limited to the skin of the lower leg, with redness and swelling around the operative site. It is important to contact me if this is the case, as you will need treatment to prevent infection from spreading to the hip joint.

Dislocation
It’s important to adhere to the restrictions that are placed on your movements in the first 6 weeks after surgery. Dislocation is usually painful with shortening of the leg and inability to weight bear.

If you think you may have dislocated your hip replacement, go to your nearest Emergency Department for assessment.

Ankle and foot swelling
This is normal to an extent after surgery and reflects the effects of gravity on a swollen hip.

Blood clots may form in the deep veins of the calf or leg. Rarely these clots can travel to your lungs (known as pulmonary embolus), which can affect your breathing. During your inpatient stay, I generally prescribe blood thinners to help prevent clot formation (although no medication is 100% effective in preventing clots). If you do have a large clot, you may require longer-term blood thinning medication.

Need for revision surgery
For most patients, a hip replacement will last for life. However, if the prosthesis wears out or breaks, revision surgery will be required to remove the existing prosthesis and insert a new one. Revision surgery is often more complex than the initial surgery and is associated with longer recovery time.

Damage to structures in the hip joint
is very rare. If there is damage to a surrounding structure, repeat surgery may be required to restore function.