Innovations in joint replacements make surgery safer and more effective

Joint replacements are some of the most common orthopedic surgeries. In the United States, nearly 800,000 people get a knee replacement and almost 550,000 get a hip replacement each year. As people continue living longer, these procedures will become even more common.

For years, researchers have been developing and perfecting joint replacement techniques and technologies. Thanks to these innovations, the operation is now safer and more effective than ever before. Timothy Costales, MD, explains how.

Robotic-assisted surgeries and personalized planning software

Robotic-assisted surgery is becoming increasingly common in orthopedic care. The Mako SmartRobotics™ system is one of several types of robotic systems that surgeons can use for hip or knee replacements. It’s what we use at Inova – it’s the method with the longest track record and has been shown to offer a more personalized surgical plan.

“It’s common to think that robotic surgery means a robot is performing the surgery. It’s not that at all,” says Dr. Costales. “The robot is basically a computer assistance program that allows us to plan for and perform the surgery with unparalleled levels of accuracy.”

Benefits of robotic techniques in hip replacements

The Mako SmartRobotics system offers surgeons and patients several benefits, including:

• Implant placement: With robotic assistance, surgeons place implants within one degree of the planned location.
• Range of motion testing: Spine stiffness can limit the range of motion in your pelvis. If your spine is stiff, you may have less stability after a hip replacement. Patients get X-rays while seated and standing to measure their spine stiffness. The Mako system then predicts how well your joint implant will move after surgery. Assessing range of motion and adjusting surgery accordingly can improve outcomes and reduce dislocation rates.
• Safe preparation and insertion: The system features AccuStop™ haptic technology. This feature provides visual, auditory, and physical feedback that helps surgeons stay within the planned boundaries when operating.
• Size matching: In the past, surgeons ordered 2D imaging before a hip replacement to estimate which size implant to use and where to place it. The Mako system allows surgeons to use a 3D CT scan for more accurate size matching.

Direct anterior approach to hip replacement

Traditionally, during a hip replacement, surgeons made an incision at the back of your hip. This approach, called a posterior replacement, involves making incisions through your hip muscles to access your joint. At the end of the surgery, the surgeon repairs these muscles.

A newer technique, called anterior hip replacement, uses an incision on the front of your hip. With this approach, surgeons can operate by slightly stretching your muscles and inserting surgical tools between them.

Anterior hip replacements can be more challenging procedures, requiring specialized expertise and experience. They can also offer significant benefits.

Benefits of the anterior hip replacement

The anterior approach uses a smaller incision than the posterior approach. The smaller incision combined with no muscular incisions means faster healing. Patients who get an anterior hip replacement tend to return home quicker with few to no activity restrictions.

“When you combine the anterior approach with the Mako SmartRobotic system, patients benefit from range of motion planning as well as a less complicated surgery,” says Dr. Costales.

He also explains that without the robotic system, surgeons typically take X-rays during surgery to confirm implant positioning. But with the Mako, preoperative imaging allows for a precise surgical plan to be “preloaded” into the system.

New implants reduce complication rates

While the anterior approach offers excellent outcomes, it can be a more challenging surgery to perform. During a hip replacement, your surgeon removes the damaged head of the thigh bone (femur). They replace it by inserting a metal stem (femoral stem) into your femur.

In the anterior approach, this part of the replacement can be tricky. An inexperienced surgeon may accidentally break or injure the femur while inserting the femoral stem.

Femur fracture after hip replacement surgery is the second most common complication of a hip replacement. In the last seven years, manufacturers have adjusted the design of the femoral stem to minimize fracture risk both during and after surgery.

Benefits of advancements in joint implants

Today’s implants contain femoral stems with optimized:

• Design: New femoral stems now include a collar-like lip. When the stem inserts into the femur, the collar helps prevent the femoral stem from rotating too much. This reduces the risk of twisting and fracturing your leg after surgery. Studies have shown that the collar alone increases the resistance to fracture risk by up to 66%. 
• Material: Today’s implants have a gray coating called hydroxyapatite. This material is easier for your existing bone to grow into, which improves healing and long-term outcomes.
• Shape: Older femoral stems were rectangular. When you place a rectangular stem into the hollow tube of the femur, it’s literally putting a square peg in a round hole. Today’s femoral stems are a triple tapered cone. This shape fits more smoothly into the femur and offers better stability.
• Size: The newest stems are slightly smaller and more curved than they were several years ago. Their size makes them easier to place in the femur, which further reduces fracture risk.

Optimizing joint replacement outcomes

Robotic systems, anterior techniques, and newer implant innovations improve patient outcomes and decrease surgical risks. Orthopedic surgeons at Inova use all of these options to deliver the smoothest surgical experience possible.

While these innovations are important, it’s also vital to find a surgeon who understands traditional techniques. “If any unforeseen problems arise during surgery, you want a surgeon who can pivot to keep you safe,” says Dr. Costales. “Technology is one piece of the puzzle, but finding a surgeon you connect with and trust is still the most important thing.”  

Learn more about joint replacement at Inova or call 571-472-6464 to schedule an appointment.