Robert Klapper, an orthopaedic surgeon at Cedars-Sinai, visited the La Brea Tar Pits and Museum for the first time in 1998 with his then 12-year-old daughter. Walking among the pristine sets of bones on display, he couldn’t help but wonder: Where were the ones with irregularities?

“Where is the arthritis? Where are the fractures? Where are the abnormalities?” said Klapper, co-director of the Cedars-Sinai joint replacement program.

Robert Klapper’s work with fossils could pay off for future patients. (photo courtesy of Cedars-Sinai Medical Center)

He approached a security guard at the museum, who led the surgeon to Chris Shaw, the museum’s onetime director of collections. They walked into the depths of the museum, into a room with rows of drawers. Shaw pulled one open and showed Klapper two saber-toothed cat pelvices.

In the following years, Klapper, researchers from the museum and staff from the S. Mark Taper Foundation Imaging Center analyzed the bones with advanced CT scans.

“The most modern technology allowed these bones to speak to us, and they had a lot to say,” Klapper said.

The results shed some light on the study of whether saber-toothed cats hunted alone or in packs.

“So now I went from being a tourist annoying the security guard to him going, ‘Oh my god,’” Klapper said of Shaw’s reaction.

One of the bones revealed that the cat had been born with dysplasia, an abnormal development of the hip joint. Scientists had originally believed that the cat died of infection. But if it had been born with dysplasia, then the animal would have walked with a limp and been unable to chase down its prey. To survive into adulthood, as it did, would have required care from a pack.

“If it’s a fact that this is how this animal was born, then it’s a fact that someone else had to feed it,” Klapper said.

After inhabiting present-day Los Angeles more than 10,000 years ago, approximately 2,500 saber-toothed cat skeletons have been evacuated from the La Brea Tar Pits and studied, according to the museum.

“The first patient at Cedars-Sinai was a saber-toothed cat when you think about it,” Klapper said.

Klapper, who has operated on 7-foot-1-inch Basketball Hall of Famer Wilt Chamberlain and 3-foot-6-inch actor Tony Cox, also saw the possibilities for helping a wider array of patients.

“What if you’re 7 foot 1? We don’t have prostheses that fit that height,” he said. “We also don’t have prostheses that fit someone small. … What we’re doing is taking a CT scan to build the anatomy and then a prosthesis.”

Melding two seemingly disparate fields, in this case evolutionary biology with surgical techniques, is emblematic of Klapper’s past. As an undergraduate at Columbia University, he majored in art history even though it could have complicated his ability to get into medical school. He still combines both of those areas of expertise when he travels to Carrara, Italy, to sculpt with the same type of marble preferred by Michelangelo.

“I love being creative and I just love cross-fertilizing,” Klapper said.

Twenty years after his initial visit to the museum, during which much of his time was occupied in surgery and hosting the weekly Weekend Warrior podcast on ESPN radio, Klapper’s collaboration with the museum continues to gain momentum. Modern imaging technology and the promise that the results will one day translate to better treatment options have bumped the project to the forefront. He said he approaches his partnership with the museum with the mindset, “What else are they going to find and how can I help them?”

Shaw, who had retired since that initial meeting with Klapper, now serves as a research associate for the museum and will work with Klapper. Aisling Farrell, the museum’s collections manager, is also working on the project.

“I’ve known that we’ve needed to do this for ages,” she said in a Cedars Sinai blog post.

An exhibit based on the findings so far is also in the works.

“If there’s one kid who sees this exhibit and gets inspired to do something like this with their life, it’ll all be worth it,” Klapper said.