ST. PAUL — The Minnesota Department of Corrections has hired a new firm to manage medical care for the state’s 9,000 prison inmates.

The department hired St. Louis-based Centurion Managed Care, a Fortune 500 health care company that manages medical care under public contracts in several states.

In a statement, the department said that Centurion Managed Care is expected to “deliver significant savings to taxpayers while improving the quality of care for offenders incarcerated in the state’s prison system.”

The department severed ties with a national company that was the target of lawsuits and staff complaints over substandard care.

A 2012 Star Tribune investigation found that at least nine Minnesota inmates had died since 2000 due to denial or delay of care while Corizon Health was the state’s prison medical contractor. More than 20 had suffered serious or critical injuries during that period, the newspaper’s investigation found.

Since then, the department has paid more than $1.8 million in wrongful death and negligence cases, including a $400,000 settlement in May to the family of a Rush City inmate who died in 2010 after being left alone in his cell while suffering a nightlong series of seizures.

The department’s announcement did not address past cases. But Corrections Commissioner Tom Roy released a statement praising Corizon for introducing managed-care efficiencies to Minnesota’s prisons and providing “excellent service to the state.”

The contract with Centurion takes effect Jan. 1 and will cost the state $67.5 million through 2016. It replaces a contract with Corizon, which has provided the Minnesota Department of Corrections with physicians, pharmaceutical services and medical specialists for the past 15 years.