"Bill," an employee at Walmart, had been suffering from mild neck pain and a tremor in his hands. A local surgeon recommended spine surgery as the next course of action.

Walmart decided to send him and his wife on a flight to a hospital in another state, all expenses paid, so he could get a second opinion. He saw a team of clinicians at Geisinger Medical Center, a top hospital system in Pennsylvania. They noticed a subtle shuffle in his step and diagnosed him with Parkinson's Disease.

The employee avoided a painful, expensive surgery that he did not need. Walmart (which is self-insured) saved about $30,000 it would have paid for that surgery, and it also benefited when he went back to work after his symptoms improved. Geisinger got paid for the consult.

In the end, Bill's story, which both Geisinger and Walmart shared this week with permission, was a win for everyone. (The study used "Bill" as a pseudonym to protect the employee's privacy.)

But it also speaks to a larger trend: U.S. employers are getting increasingly fed up with the myriad problems with the U.S. medical system. Companies pay for about 49 percent of Americans' health care, and are facing rising costs without any real improvements in outcomes.

So Walmart and its partners published a case study detailing their approach in Harvard Business Review, in an effort to disseminate its ideas more broadly.

Walmart's Lisa Woods, who wrote the piece with Jonathan Slotkin, a director of spine surgery at Geisinger, and Ruth Coleman, a health executive and nurse, described how they've succeeded by focusing on more than just lowering costs. They also looked for ways to improve overall health outcomes for their workers, so they could return to work, including by offering travel programs for workers to see doctors at top hospitals who were not incentivized to push for an unnecessary surgery.