Jacob Elkins: Engineering solutions for bariatric joint replacement

When orthopedic surgeon Jacob Elkins (13MD-PhD, 18R) began college as a chemical engineering major, medicine wasn’t on his radar. At 20, knowing little about health care, he walked into a nearby Veteran Affairs hospital and volunteered. There, he was asked to hold a patient’s legs during a hip replacement procedure — a task that introduced him to the world of joint reconstruction and left him “blown away” by what was possible. 

“I didn’t even know you could replace a hip,” Elkins says. “From that moment, I was hooked.” 

The experience sparked a dramatic career pivot. While completing pre-med requirements, Elkins earned a master’s degree in chemical engineering and dove into research on joint biomechanics. His search for a program that combined engineering and medicine led him to the University of Iowa and the lab of Tom Brown, PhD, MS, a world-renowned expert in orthopedic biomechanics who helped shape his career. 

Today, Elkins is co-director of the Orthopedic Biomechanics Laboratory and the Adult Hip and Knee Reconstruction fellowship program, based in the UI Department of Orthopedics and Rehabilitation. He also leads a specialized clinic focused on bariatric arthroplasty — hip and knee replacements for osteoarthritis patients with morbid obesity. 

Osteoarthritis is likely influenced by genetics, though the specific genes remain unclear. It’s known that risk factors like morbid obesity dramatically increase the likelihood of joint damage. Arthritis has no cure outside of surgery, and it’s a chronically progressive disease that affects quality of life. 

Surgeries to treat hip and knee arthritis are among the most successful in medicine, boasting success rates over 90% and dramatically improving quality of life. Yet for patients with a body mass index (BMI) over 40, access to surgery is often denied due to higher complication risks. 

BMI is calculated by dividing weight by height squared, but it doesn’t distinguish between muscle and fat or account for malnutrition. Relying on BMI alone can prevent patients from receiving the care they need. 

“It’s a huge problem. Tens of thousands of Iowans live with crippling arthritis and limited options,” Elkins says. “If we can identify another metric besides BMI to screen patients, we might expand surgery to a significant portion of people who need it.”

Elkins’ research aims to do just that. Using electrical bioimpedance technology, his team performs body composition analysis to move beyond BMI. By measuring muscle mass, fat, and edema — swelling caused by excess fluid — his clinic develops individualized optimization plans, often involving resistance training, nutritional counseling, and physical therapy. The focus is on improving health safely, not just meeting a weight cutoff. 

“In broad terms, my research is: How can we do that better?” Elkins says. “I believe there’s a path forward to treating these patients surgically and improving their quality of life without denying care.” 

Patients who complete a personalized optimization plan report high satisfaction, Elkins notes, even though progress takes time. Preliminary findings suggest edema may be a significant factor in postoperative complications, particularly infection and wound healing. And because edema can be measured, tracked, and potentially controlled, it could become a promising metric for determining surgical readiness. 

The next phase of Elkins’ work focuses on refining these protocols and improving implant longevity. He hopes to validate new risk metrics beyond BMI through larger, multicenter studies and investigate implant-specific parameters that could improve durability for high-BMI patients. 

At the same time, his team is exploring biochemical factors in obesity-related joint disease, including how hormones influence tissue around the joints, which may open doors to preventive strategies. Elkins is also building collaborative networks to support research nurses, coordinators, and multidisciplinary teams dedicated to optimizing joint replacement care for bariatric patients. 

“These steps will help us move from identifying problems to implementing solutions,” he says. “Ultimately, it’s about giving more patients access to life-changing surgery without compromising safety.”