A 10-year longitudinal study funded by NIH, the Osteoarthritis Initiative examined knee osteoarthritis (OA) and found that 83% of cases occurred in only one or two of the knee’s three compartments. This finding suggests many patients may be candidates for partial knee arthroplasty (PKA) rather than total knee replacement.

“Partial knee preserves the cruciate ligaments, giving patients more flexion and stability for a more normal-feeling knee,” says Duke Health joint replacement surgeon William A. Jiranek, MD. “Partial joint replacement largely isn’t being done due to unfamiliarity with the procedure or concerns about revision.”

“Registry data has suggested a higher revision rate for partial knee than total knee in the past,” acknowledges joint replacement surgeon Harold I. Salmons, MD, MS, who joins Duke Health after studying at the Mayo Clinic and Hospital for Special Surgery. “As more robotic surgery data comes out, I think the outcomes for PKA will be closer to total knee, as long as patients who undergo PKA are carefully selected by the surgeon.”

Clinical results have improved significantly over the past 20 years as surgeons have better defined the ideal PKA candidate. Additionally, evidence from the TOPKAT study researchers suggests that PKA patients have a higher activity level on average than total knee patients, but revision rates were comparable.

Salmons highlights the improvements robotic surgery offers for PKA. “Classically, PKA is a more technical operation, and using manual or conventional instruments runs the risk of technical errors or slight deviations, due to intraoperative references,” he says.

While high-volume PKA surgeons have the skill to operate with excellent results, adding a surgical robot can increase the procedure’s accuracy. “The robotic option is very powerful because the surgeon can review the osseous anatomy, alignment, and ligament tension of the knee and then precisely place the PKA implant where cartilage and bone once were,” Salmons says. “Technique and precision really matter within the contours of the knee, and along with advanced imaging, the robot offers the ability to achieve incredible precision and provide a means to truly resurface the involved, painful compartment of the knee.”

As an advanced orthopaedics center, surgery isn’t the only option Duke offers for knee OA. Duke Health offers the full spectrum of nonsurgical treatments including steroid and orthobiologic injections for knee OA such as platelet-rich plasma or stem cells.

As part of this comprehensive care, both Jiranek and Salmons highlight Duke’s Joint Health Program (JHP) for patients with OA of the hip, knee, shoulder, or carpometacarpal joints. Primary orthopaedic providers in the JHP manage patients’ pain, physical and occupational therapies, and education in related areas to help patients regain function and mobility.

“Our best data for relieving arthritis symptoms support strengthening the muscle envelope around the knee,” says Jiranek. “In the JHP, we also develop the skills to cope with an exacerbation of pain, which almost every patient faces.” The JHP helps patients to improve nutrition and sleep disrupted by pain.

“We’re always happy to see anyone with hip or knee pain,” Salmons says. “We don’t have to wait until a patient has an end-stage problem: we’ll direct the patient into the correct pathway and address their pain much sooner with early referral.”