Walmart is aiming to lower healthcare spending by requiring employees to travel to certain hospitals for spine surgeries, according to The Wall Street Journal. Here are four things to know:

1. Over the past five years, Walmart has encouraged employees to undergo a variety of procedures, including spine, heart, hip and knee surgeries, at hospitals known for providing high-quality care. As an incentive, the retail giant offered to pay for the full cost of the procedures and travel.

2. Beginning in January, Walmart is mandating the travel for spine surgeries in an effort to lower healthcare costs and reduce unnecessary procedures.

3. Walmart has teamed up with major health systems for the mandatory program, including Rochester, Minn.-based Mayo Clinic, Danville, Pa.-based Geisinger and Houston-based Memorial Hermann Health System.

4. Walmart, which provides health benefits that cover more than 1 million people, will not require workers to travel to designated hospitals for heart surgeries and other procedures included in the voluntary program.