Austin Hopp, 27, was sentenced to five years in jail and three years probation on Thursday for second-degree assault. He had pleaded guilty in March to the charges.
The former officer, who according to The Denver Post expressed remorse in court for his behaviour, was charged in April 2021 for assaulting the victim, Karen Garner.
It came after lawyers for her family released previously unseen body camera footage of Hopp grabbing and pushing Ms Garner, who has dementia.
She had been accused of stealing items worth about $14 (£11) from a nearby Walmart, and Hopp later joked about the arrest with colleagues. Footage also showed him pushing Ms Garner up against a car.
Ms Garner’s family say she suffered a dislocated shoulder and broken arm from the arrest, with the city of Loveland already agreeing to settle a lawsuit for $3m (£2.4m). Most of the money will go towards her care, her relatives say.
During the sentencing of on Thursday, Larimer County District Judge Michelle Brinegar called the former officer’s actions toward Ms Griner, “deliberate, deceitful and calculated,” The Post reported.
“This case is not about a mistake,” said the judge. “This [is] about a young officer who used his position of power and authority to show off his toughness, disregarded any sense of humanity and showed an alarming deal of criminal thinking.”
Hopp, who resigned from Loveland’s police department in April 2021, could have been sentenced to eight years in prison, and up to 32 years under an original, more serious assault charge.
The case involving another officer who was at the arrest of Ms Garner, Daria Jalali, is ongoing. She has been charged with failing to report use of force and misconduct, according to The Washington Post.
Additional reporting by The Associated Press.