Globally, from 1990 to 2020 hip osteoarthritis patients increased from 17.02 to 18.70 per 100,000 people. This upward trend is expected to continue, due to the rapid aging of the world’s population and the increasing rate of obesity observed worldwide.

The risk of hip osteoarthritis is 18.5% for men and 28.6% for women. Research shows that there is a 25% risk of developing hip osteoarthritis for those who live to age 85. All of the above explains the growing interest of the orthopedic community in improving both surgical techniques and materials used in total hip arthroplasty.

“Total hip replacement is proven to be a safe surgical procedure with spectacular results in improving patients’ quality of life at a relatively low cost. “Hip replacement surgery not only improves quality of life, but may even increase life expectancy, according to newer studies,” says Dr. Mr. Dimitrios Dovris Orthopedic Surgeon, MD, PhD, D.Av.Med at Metropolitan Hospital and goes on to explain everything about total hip replacement:

Materials

Total hip arthroplasty, like any other surgery, has a low rate of complications. The long-term preservation of the good result of arthroplasty depends on factors related to the patient, to the experience and surgical technique of the surgeon, but also to the quality and combination of the materials used.

The characteristics of different implants and conflicting studies in the literature make it difficult to choose the best implant. The biggest debate concerns the use of different materials on the charged surfaces of the prostheses. CoC (ceramic on ceramic) implants show the least wear, but have a high risk of breakage and cracking. CoPs (ceramic on polyethylene) have a higher wear rate than CoCs but are more durable. MoPs (metal on polyethylene) have the lowest price but the highest wear rate.

“There is no such thing as a perfect implant, but there is an ideal implant for every patient. Implant-to-patient matching and implant selection is a difficult task that should take into account many factors such as bone quality and the patient’s general health status. A good initial implant selection will determine its survival rate and, consequently, patient satisfaction and will minimize both the social and economic costs created by the subsequent total hip arthroplasty revision. The development of new biomaterials that combine the use of new nanoparticles with antimicrobial activity to reduce the risk of infection, among other improvements, will increase the success of these complex surgeries and the long-term survival of the implant,” he points out.

Accesses

Surgical access to the hip to follow placement of the materials has traditionally been done laterally or posteriorly. In recent years, anterior access and Anterior Minimally Invasive Surgery AMIS (Anterior Minimally Invasive Surgery) have seen a leap forward. It tends to become the standard approach both in the US and globally.

“AMIS is characterized by a reduced skin incision and its difference from other methods is that the muscles and tendons are simply displaced temporarily to place the materials. In this way, the injury to the soft tissues, vessels and nerves of the area is greatly reduced. The advantages of the method are reduced post-operative pain, shorter recovery and hospital stay, smaller skin scar, faster return to daily activities and less blood loss.

Another very important difference is the reduced risk of dislocation and the prevention of lameness which is contributed to by preserving the muscles rather than cutting them. Another advantage is that due to the supine position of the patient during the operation, it is possible to use radiological control intraoperatively, which is very important to avoid disequilibrium postoperatively”, emphasizes the specialist.

AR AUGMENTED-REALITY

“Guided hip replacement is based on the CT scan of the hip taken before surgery. The three-dimensional nature of a CT gives more detail about the patient’s anatomy than two-dimensional radiographs, thereby allowing a computer model of the pelvis and femur to be created. This model is used to plan the size, orientation, and location of hip replacement materials. The computer model and drawing are loaded into the AR headset, allowing the surgeon to visualize them directly while performing the operation.

The surgeon can thus see a patient’s unique anatomy to accurately place the implant. AR technology holds great promise for hip surgery, both for pre-operative simulation and training of surgeons and for enabling orthopedic surgeons to operate more precisely and safely,” he explains.

MAKO Robotic Arthroplasty

“The procedure begins with a special CT scan of the hip joint, using MAKO software, which creates a 3D model of the affected hip on the system’s computer. The surgeon then elaborates and personalizes the entire procedure, depending on the particularities of each patient, thus creating a personalized pre-operative plan.

The surgeon uses minimally invasive surgery (MIS) to expose the joint. Then, guided by the surgeon and following the preoperative plan, the MAKO robotic arm prepares both the acetabulum and the upper femur and helps place the implants with extreme precision and without margin of error, avoiding any misalignment problems.

Total hip arthroplasty remains an exceptional procedure that often changes the quality of life for patients. There will always be debate about the potential benefits and outcomes of different approaches, different materials for the construction of implant posts and loading surfaces, and differences in restorative protocols. Surgeons should consider the needs of each individual patient according to their anatomy, age, and expectations.

Robotic orthopedic surgery is the most modern medical technology available to treat arthritis and serious conditions of the knees and hips,” concludes Mr. Dobris.

*Metropolitan Hospital stands out in Greece as the first hospital in Europe to adopt and apply this technology, with 8 years of experience and more than 1,500 operations with the MAKO system, while it is an international Center of Excellence for this technique.