The facts about

total hip replacement surgery

By ShareMD Connect

A total hip replacement (THR) has proven to be one of the most successful surgical inventions of the 21st century. The first modern iteration was performed in the 1960s, with highly favorable results. THR surgery—also called total hip arthroplasty (or THA)—has been used ever since and is extremely effective in relieving pain, restoring mobility, and improving the overall quality of life.

Approximately 500,000 THRs are performed each year in the United States alone and is only expected to increase. The satisfaction rates of patients who have undergone THR speak for themselves:

• Ninety-one percent (91%) of patients who had moderate pain before their first surgery reported mild or no pain after five years.  
• Eighty-nine percent (89%) of patients with severe pain before their first surgery reported mild or no pain after five years.

Even though the results of a THR are incredibly positive, many people are still choosing to live with chronic hip pain. Why? Mostly because they don’t have all the facts.

What Does a THR Involve?

In simplest terms, a THR involves the surgical removal of broken, splintered, or arthritic parts of the hip joint, consisting of cartilage and bone. The “ball and socket” of the joint is then replaced with an artificial structure. 

Typically, the replacement unit is made of high-performance polyethylene plastic, though it may also be ceramic, plastic, or even metal. The deteriorated head of the femur—the bone that connects your leg to your hip socket—is removed, and a metal stem is inserted in the hollow socket.

During the procedure, the surgeon creates a human-made bearing surface that mimics the hip joint and bones’ function with the metal stem, artificial femoral head, and composite socket to facilitate a smooth, gliding movement. Whereas the joint and bones of an arthritic hip grind and catch each other, causing pain, the artificial ball and socket can function as a well-oiled, frictionless machine.

Three Types of THR: Pros and Cons

There are three kinds of surgical approaches for THR: posterior, lateral, and anterior. This means in each approach, the surgeon accesses the hip from either the rear (posterior), side (lateral), front (anterior), or a combination of these. There is some debate about the best approach, and it varies depending on the surgeon and the individual receiving the procedure.

So let’s take a closer look at these three different surgical approaches and what advantages and disadvantages each offer.

Posterior Approach THR

The posterior hip replacement approach requires surgeons to cut muscles and other soft tissue at the back of the hip, including:

Lateral Approach THR

Like the posterior approach, the direct lateral approach to hip replacement also requires cutting muscles. The abductor muscles (gluteus medius and minimus) are affected in this surgical approach. 

Any muscles that are cut during posterior or lateral surgeries are repaired and reattached at the end of the surgery.

Anterior Approach THR

The anterior hip replacement approach requires the surgeon to work between the muscles, pushing them aside to reach the hip joint. This natural separation allows ready access to the hip joint with minimal or no muscle cutting. The surgeon works in between muscles supplied by different nerves.

The posterior and lateral approaches provide a better view of the hip joint. Conversely, the anterior approach restricts the surgeon’s visibility of the hip joint during surgery. This makes it a more technically challenging procedure for less experienced surgeons. Due to the technically demanding nature of this procedure, surgeons must have extensive training and experience to attain a high level of expertise with the anterior approach THR.

While wound-healing issues are usually mild and self-limiting (meaning they typically resolve over time, even without medical treatment), some may involve an infection of the new hip joint, which is a serious concern.

There is also a potential risk of nerve injury with any hip replacement approach. However, in an anterior hip replacement, the surgical area is located near the lateral cutaneous femoral nerve, which runs down the front of the pelvis and past the hip to supply sensation to the outer thigh (it does not affect muscle control or strength).

Following anterior hip replacement surgery, there is potential for numbness in the thigh and, in rare cases, a painful irritation of the skin supplied by that nerve, known as meralgia paresthetica. This condition is rare and happens in less than 1% of patients.

What about Robotic Surgery?

THR can now also be performed with a cutting-edge technique called robotic-arm-assisted joint replacement. During this procedure, the robot enhances the surgeon's expert skills for even more precise procedures, which is important because every hip is different in very subtle ways. A fraction of an inch can be the difference between a healthy joint and one that causes pain and immobility. 

Patients choosing to utilize robotic surgery undergo a specialized CT scan that helps the surgeon plan every step of their surgery, including picking the best implant size, location, and positioning. Although the surgeon uses the robotic tool throughout the procedure as a guide, the robot does not perform surgery. All of this, put together, can result in faster recovery times, fewer complications, and a lower likelihood of revision surgery.

Bottomline

It is important to remember that a successful hip replacement surgery depends on many factors besides the surgical approach. For example, the knowledge and skill of the surgeon, the type of hip prosthesis used, the patient's weight and build, and the patient's ability and willingness to participate in surgical preparation and post-surgical rehabilitation are important factors.

While a THR is not ideal for everyone, it can be life-changing surgery for those severely limited by hip pain. Take our assessment today to see if it might be time to consider hip replacement surgery and begin your path to a pain-free future.