Perioperative platelet-rich plasma (PRP) in total hip arthroplasty
Total hip arthroplasty, which is also known as hip replacement surgery, is often performed to alleviate the pain associated with arthritis in the hip joint. Arthritis in this area can cause pain, limited range of motion, and cause swelling and inflammation.
Dr. Wolff, wants you to know that these surgeries can be quite effective, but there is a possibility of gluteus medius tendon weakness and pain because of it. Which is why we often recommend our patients to explore platelet-rich plasma therapy as a treatment option that can be used during the hip replacement procedure to help restore tendon strength and muscle function, improving the results from the surgery.
What is a Total Hip Arthroplasty?
In order to access the hip joint, the gluteus medius muscle is cut and moved out of the way. Then, the hip replacement surgery involves removing the head of the femur and the cartilage in the socket attached to the pelvis and replacing them with a joint made of metal and plastic.
The new ball-and-socket joint is connected to the femur bone using either cement or another medium that allows the bone to grow together with the new joint, and the socket is connected to the hip bone in the same manner. The ball on the end of the femur is then inserted into the new hip socket. After these steps have been completed, the gluteus medius muscle is then reattached and the wound is closed up.
Potential Muscle Complications Following Surgery
While the surgery itself is often quite effective, there is always a chance of complications. One of these potential issues relates to the reattachment of the gluteus medius muscle, especially when the Hardinge approach is used. In this approach, the gluteus medius and gluteus minimus muscles are split and are then reattached at the conclusion of the procedure.
Six months after surgery, hip muscle weakness is common in up to 85 percent of patients. This figure remains at 10 percent after two years of recovery. This muscle weakness can affect a person’s gait, or ability to walk correctly.
In some cases, the gluteus medius can become easily strained during recovery due to its weakness after reattachment. A muscle strain can lead to pain and discomfort in the area and may prolong the necessary recovery time substantially.
The Use of Platelet-Rich Plasma
One of the ways that this muscle weakness can be addressed is through the use of platelet-rich plasma, or PRP. This plasma is derived from your own blood. After a sample is drawn, it is placed in a centrifuge, and the red and white blood cells are removed, leaving only the plasma portion of the blood. Then, this sample is centrifuged again to allow the platelet-rich portion to be isolated.
Platelets contain growth factors that are critical in the tissue healing process. Each plays a specific role in this, such as stimulating new blood vessel formation, reducing levels of inflammation, recruiting additional cells to the area, improving cellular communication, and more.
This platelet-rich sample can then be injected directly into the damaged tissue, whether it is the tendon, muscle, or soft tissue. The abundance of platelets and growth factors helps to stimulate the regrowth and reparation processes, reducing recovery time and improving functionality more quickly.
In the case of a total hip replacement, the PRP can be injected into the incision line where the gluteus medius tendon was cut and into the area where the tendon attaches to the bone. Because the incision is closed and the injections are placed into the tendon, the PRP will not leak and will stay concentrated in the desired area.
A pilot study was performed that included 12 patients who required total hip arthroplasty surgery. During the procedures, half of the patients received PRP injections while the other half received placebo injections. The surgeon was unaware of which treatment they were providing.
One way the effectiveness of the injections was analyzed was by using the Oxford Hip Score test. This produces a score based on a patient’s self-reported functionality and pain levels. After three months, the PRP group noted improvements of 23.5 points, and the placebo group noted improvements of just 20.2 points.
Abduction strength was also measured for both groups. One of the major functions of the gluteus medius is hip abduction, so this measure provides great insight as to the effectiveness of PRP. Researchers noted a 39.1 percent increase in strength with the PRP group, but the placebo group only had a 6.2 percent improvement.
Hip replacement surgery is quite common, making up nearly one-third of joint replacement procedures in the United States. In one of the most common hip arthroplasty approaches, the gluteus medius muscle must be cut and reattached, and hip weakness is a common side effect of this procedure. PRP therapy, when used in conjunction with the surgery, can greatly reduce these muscular issues, helping to improve strength, reduce pain, and limit recovery setbacks following the procedure.