Mainstream total hip arthroplasty as we know it began in the early 1960s with Sir John Charnley’s low-friction arthroplasty. Over the subsequent decades, hip replacement has evolved into one of the most successful medical operations. Success rates between 90%-95% are often quoted in the literature.
As such, modern hip replacement is often called the “operation of the century” by both patients and surgeons alike. According to the American Academy of Orthopedic Surgeons, the demand for hip replacement surgery is expected to increase 174% from 2005-2030. This translates to around 572,000 hip replacements per year in the U.S. Nearly 30% of these will be in patients younger than 55 — an age traditionally felt to be “off limits” to hip replacement due to the potential need for multiple revision procedures later in life.
I believe several factors are driving this demand. Older patients want to stay active and maintain their independence longer into retirement. Younger patients do not want to wait to reach an arbitrary age when they feel they are missing the precious moments of life now. In addition, materials used in the manufacture of hip replacements have improved, allowing the potential for greater longevity of components.
Recent studies of modern designs reveal no evidence of significant wear or other potential causes of failure after over 20 years in service. I strongly suspect we will see these implants perform well beyond 30 years in service.
I also believe our improved understanding of surgical techniques and perioperative care have not only expanded access to hip replacement but also made it safer and more effective. When I began training, even experienced attendings often required two hours for an average hip replacement. Patients usually were in bed for the first 24 hours with a morphine pump. Most patients were not discharged until the third post-operative day and most required limited weight bearing and cumbersome hip precautions for several weeks after surgery.
To contrast, hip replacement can often now be performed in less than an hour with patients bearing full weight as soon as their spinal wears off (usually within an hour or two of surgery). Most patients are candidates for same-day discharge to home. Our perioperative multimodal pain regimens have allowed opioid-sparing surgery and in many cases, patients do not need opioid pain medications or need them for only a few days.
In my practice, I also attribute my adoption of the anterior approach to the hip as one of the most important reasons patients do so well. The “approach” is how a surgeon accesses the hip joint. Traditionally, most surgeons either used a posterior or lateral approach.
While successful hip replacement can still be performed with these approaches, some notable disadvantages exist. Namely, they require violation of muscle. The gluteus maximus, piriformis, gluteus medius/minimus and short external rotator muscles may all be affected. As a result, some surgeons do not allow patients to bear full weight immediately and often require a period of “hip precautions” to avoid dislocation of the hip.
The anterior approach is a modification of an approach used for many years by orthopedic traumatologists to repair acetabular fractures. It allows a patient to remain supine through the procedure and avoids division of any major muscle, typically resulting in faster recovery — especially within the first month. In addition, the hip is quite stable, so formal hip precautions are usually unnecessary, and full weight bearing is almost always allowed.
As someone who trained on posterior hips, learning the anterior approach has been challenging but rewarding as these are some of my happiest patients.
As with anything, experience matters. There is a reason many surgeons have not adopted the anterior approach — it requires a learning curve with reports in the literature of up to 60 patients. During this time, there is an increased risk of complications — from minor to major. I have seen component malposition, fractures of the femur and acetabulum, instability and even major neurovascular injury. For this reason, some surgeons will offer the approach, but only to “routine” patients.
As someone who has performed more than 1,000 of these procedures, I find it easier and safer to use the anterior approach for obese patients or patients with cardiopulmonary problems than a different approach requiring lateral positioning. The anterior approach can often be safely utilized even for revision surgery.
While no surgery and no approach can ever guarantee a perfect outcome, the take-away message is that hip replacement is one of the most successful procedures we perform and the anterior approach has made the procedure even more successful for thousands of patients.
I often counsel patients that they will likely feel better walking out of the hospital on the day of surgery than when they were admitted. As the national demand for hip replacement continues to grow, I look forward to continuing to provide this important service to patients.
Learn more about total joint services at Northside Hospital Orthopedic Institute.
