Stem Cell Research May Shape the Future of Knee Repair

Today, if an MRI reveals a patient has lost most, if not all, of the cartilage in their knee, then their doctor will almost certainly recommend a total joint replacement. Joint replacement is a safe, effective procedure that has helped millions of people, says Darryl D'Lima, MD, PhD, director of orthopedic research at Scripps Health — and he would know. When Dr. D’Lima came to Scripps 20 years ago, his first research projects were dedicated to advancing joint replacement. 

“But there are other patients, often younger, who’ve only lost part of their cartilage, so either they don’t qualify for a total joint replacement, or replacing an entire joint isn’t necessary,” he explains. “We want to be able to do something different to help them.” 

There are treatments for these patients available now, including allograft transplant surgery, where donor bone and cartilage are used to replace a patient’s damaged tissue. This is another treatment Scripps has long been at the forefront of, thanks to the expertise of William Bugbee, MD, an orthopedic surgeon at Scripps Clinic. Still, donor shortages complicate this procedure. 

Dr. D’Lima and his team, which includes Dr. Bugbee, along with Shawn Grogan, PhD, senior scientist, Heinz Hoenecke, MD, and Tim Wang, MD, Scripps Clinic orthopedic surgeons, and Steven Copp, MD, who is also medical director of the musculoskeletal service line at Scripps Health, are working to help these patients using lab-grown tissues in place of ones that come from a donor.  

That’s where the CIRM funding comes in. With this grant, Scripps researchers will conduct preclinical trials over a five-year period. They will grow stem cells, which they’ll use to produce musculoskeletal tissues like cartilage and bone. The goal is to demonstrate that laboratory-based tissue is effective and safe. At the end of the research period, the team plans to submit their findings to the FDA and, if approved, begin clinical trials of this therapy. 

“If we are successful, at a minimum, patients who might be destined for a total joint replacement, but who have lost only part of their joints today, will not just get by, but function without pain until then,” Dr. D’Lima says. “At the maximum, it could take away their need for ever getting a total joint replacement. 

“It’s a long road, but our goal is always to bring newer, better treatments to patients. And we want to do it in a way that there’s no doubt about the safety of the procedure.”