In recent years, the frequency of hip and knee replacements in Australia has surged. 

The latest figures available, for the year 2022, there were 52,863 hip replacements, 64,846 knee replacements and 8,636 shoulder replacements. And that was a Covid affected year, when procedures in public hospitals were down by more than a fifth. 

The Australian Orthopaedic Association National Joint Replacement Registry’s Annual Report records that there were a total of 1,982,200 joint replacement procedures in that year alone.

Surveys show high levels of satisfaction, with 85% of respondents saying they felt “much better” after hip, knee or shoulder joint replacement.

Once rare, these days many of us have had a joint replacement, or know people who have.

What could be driving this trend? Advances in technology and surgical techniques, better implants, faster recovery times, and higher success rates are encouraging more people than ever to elect for total joint replacements, even at increasingly younger ages.

For those in their 40s and 50s, arthritis – specifically osteoarthritis – is the top reason for undergoing hip replacements. This condition, distinct from the usual 'wear and tear' arthritis of older age, often stems from sports injuries or motor vehicle accidents. According to Orthopaedics WA, nearly all patients under 50 with premature arthritis have an identifiable cause, such as hip dysplasia, childhood deformities like Perthes disease, femoro-acetabular impingement, joint injuries, avascular necrosis, infections, or inflammatory (rheumatoid) arthritis.

The bearing, where movement occurs, is the weakest part of a conventional hip replacement. Traditional bearings, made of high-density plastic and metal, fail quickly in younger patients. Thus, special bearings, including ceramic materials, metal bearings, and particularly hard-wearing plastics, are often chosen based on individual needs. Each material has its advantages and potential risks, requiring careful tailoring to each patient's circumstances.

Perth orthopaedic surgeon Dr Benjamin Hewitt explains that hip replacements are typically performed when the hip joint wears out, leading to pain and dysfunction that dramatically reduce quality of life. The hip joint, crucial for standing, walking, and daily activities, consists of a ball-and-socket with smooth, hard bearing cartilage. Damage to this cartilage, commonly due to osteoarthritis, results in pain and stiffness, which can become severe in some patients.

Hip replacements are generally considered when daily pain severely impacts one's ability to perform activities. The goal is to alleviate pain and stiffness, enabling patients to return to their usual activities. For those needing both hip and knee replacements, surgeons often recommend hip surgery first, as recovery from hip surgery doesn't require as much rehabilitation, making it more manageable if the knee is also painful.

Most patients experience significant recovery within eight to twelve weeks after hip or knee replacement surgery, though full recovery can take up to a year. Physical therapy is essential post-surgery, with the majority of patients regaining considerable function within two to three months. Knee replacements typically require a longer recovery time than hip replacements.

It's crucial to explore alternatives before opting for hip replacements, as they should be a last resort. Painkillers, injections, and exercises can provide temporary relief, but if the hip joint is severely worn out and symptoms become debilitating, a hip replacement may be the only long-term solution.

How long will a hip replacement last? 

As with all mechanical devices, hip replacements can fail, usually when the bearing surface wears out and the components become loose. The Australian National Joint Replacement Registry records and analyses the details of all hip replacements performed in the country, offering data on their longevity. On average, 94 percent of joint replacements are functioning well at the 10-year mark, and 90 percent at 15 years. This means there's a 90 percent chance your hip replacement will still be fully functioning 15 years post-operation – a promising outlook.

With the remarkable advancements in joint replacement technology and techniques, individuals are gaining new leases on life, free from the debilitating pain of worn-out joints. While the decision to undergo a hip or knee replacement is significant, the potential benefits in terms of pain relief and improved quality of life make it a viable option for many. As we continue to innovate and improve these procedures, the future looks bright for those seeking to regain their mobility and enjoy life to the fullest.

Photo: Hospital for Special Surgery, New York.