Robotic Assisted Total Hip Arthroplasty: A Tool for Improving Precision

Degenerative joint diseases (DJDs) are chronic conditions often resulting in pain and the loss of an active lifestyle and quality of life. Osteoarthritis (OA) is the most common type of DJD (Fig. 1). Other causes are Post-traumatic arthritis, Rheumatoid arthritis, Avascular Necrosis and Hip Dysplasia. Total hip replacement done to manage DJD of the hip is one of the most satisfying procedures in Orthopaedic Surgery. It is also often done to treat a hip fracture in an active, independent living elderly person.

What is Total Hip Replacement?

Total hip replacement, also referred to as total hip arthroplasty, is a surgical procedure in which the ball-and-socket of the hip joint are replaced by surgical implants. A metal cup lined by a polyethylene liner replaces the socket. A ceramic or metal head attached to a metal stem replaces the femoral head. The new femoral head and cup liner provide a smooth bearing surface allowing the joint to move smoothly. Titanium alloy is used to make the metal cup and stem. Modern implants have a surface that allows the bone to grow into the implant for permanent fixation. These materials have demonstrated durability if implanted in the correct position.

Correct sizing, the accurate placement and alignment of implant components are critical factors for a successful total hip replacement. A Robotic assisted hip “MAKOplasty® “total hip, powered by the surgeon-controlled RIO® Robotic Arm Interactive Orthopedic System, provides a new level of accuracy and precision in total hip replacement (Fig. 2, Fig. 3).

How Does a Robot Help in Surgery?

A robot is a machine capable of carrying out a complex series of actions automatically, especially one programmable by a computer. Here is how we as surgeons take advantage of robotic arms to perfectly execute a preoperative plan:

1. The patient is diagnosed with debilitating hip pain from DJD based on X-ray or MRI.
2. As the surgeon determines that you are a good candidate for MAKOplasty, you will be scheduled for a CT scan of your hip.
3. The RIO® system creates a virtual model of your hip from the CT scan (Fig. 4)
4. A patient specific surgical plan is created for optimal implant size and placement, based on your unique anatomy.

Maximizing Accuracy

The plan is validated by your surgeon prior to the actual procedure. Your surgeon essentially does the whole procedure. Using real-time information and images of your hip, your surgeon knows and controls accurate implant placement (Fig. 5). Early clinical data suggests that MAKOplasty demonstrates 4-6 times greater accuracy in cup implant placement than manual techniques in laboratory settings, reducing chances for complications such as impingement (rubbing together), implant wear, and dislocation.