GILLETTE — A Gillette man has pleaded not guilty to 31 counts of aggravated child abuse.

Tyler Bryan Martinson, 28, entered a not guilty plea for all 31 charges at his arraignment Tuesday afternoon before District Judge Stuart S. Healy III.

Martinson was arrested in January after his 3-month-old son was found with 26 rib fractures and five broken bones in his legs. The worst fracture was to the child’s upper femur, according to court documents.

Martinson was supported by some of his friends and family Tuesday afternoon, including Keasha Bullinger, the boy’s mother, who was there with the baby.

The maximum penalties for each count of aggravated child abuse is 25 years in prison and a $10,000 fine.

A trial will not be scheduled until after a pre-trial conference takes place. The trial must happen within six months of Tuesday.

The boy’s parents had taken him to the emergency room Jan. 2 because he was crying and “inconsolable,” and a popping sound from his ribs when he breathed worried them. His right leg also wasn’t moving.

Tests showed that the baby had “multiple bilateral posterior breaks to his ribs that were in various stages of healing,” according to an affidavit of probable cause filed in the case. “These breaks showed they were in three different stages of healing.”

The child also had a 45-degree angle break to his right femur along with a break to the end of the femur by his kneecap. There were two breaks in his right tibia by his ankles. He also had a break to his left femur by his kneecap, the affidavit said.

The emergency room physician told police that his injuries came from “high speed brute force” trauma like extreme squeezing or shaking the baby. She compared the amount of force necessary to create the injuries to that of a vehicle crash.

The boy was flown to University of Children’s Hospital Colorado in Aurora, Colo., for treatment of his injuries.

Martinson had been alone with the baby the night before while Bullinger worked, according to the affidavit.

Martinson told police that he thought the boy had a bowel obstruction in the middle of the night. He “was pushing on his legs, trying to help him poop because it helped last time,” he told authorities. “I must have gone to(o) hard.”

A detective asked if he thought he was pushing into the child’s ribs as he pushed on his legs. Martinson replied that he thought he was pushing into the boy’s stomach and that the baby grunted as Martinson pushed, according to the affidavit.

Martinson told police that he had noticed that he was not as gentle as he should have been with the baby because he has never had children before. He described an instance about two weeks before when he picked up the baby and left bruises on him.

He was asked if he might have picked him up too tightly that night and cracked his ribs.

“It’s hard to say,” Martinson said, according to the affidavit. “I might have, because I have in the past. I just wasn’t as gentle as I thought I was being with him.”

About 10 days earlier, Martinson said he saw bruises on the baby’s chest where his thumbs had pressed into him and knew that he had gone too far, according to the affidavit.

At the local hospital, police noted four bruises on the baby’s chest and one on his back consistent with fingertips.

At Children’s Hospital, the baby also was found to have extra fluid around his brain and an elevated liver enzyme level that is indicative of trauma, according to the affidavit.

The injuries to the child’s lower legs would be caused by “pulling or yanking” and the other injuries would come from “very forceful handling,” according to the affidavit. The doctor diagnosed them as child abuse.