St. Stephen’s/St. Agnes freshman Rita Peterson was involved in a scary ATV accident in November. (Toni L. Sandys/The Washington Post)

Soon after Rita Peterson arrived at a friend’s farm from a lacrosse tournament Nov. 11, the St. Stephen’s/St. Agnes freshman went for a group ride in all-terrain vehicles. Two people took one ATV, while Peterson joined three others in another with “a cool windshield” that looked extra fun.

It only had three seats, so Peterson sat on a friend’s lap, and the two vehicles traversed a meadow and then proceeded down a long driveway with ravine-like slopes on each side. On that path, the driver of Peterson’s ATV swerved in one direction and, trying to correct the motion, pulled the wheel back. The change was too abrupt, and the ATV lost control, flipping four times down the hill.

On the fourth tumble, Peterson’s face and hand shattered the windshield, and she fell out the side. The ATV landed across her hips.

The accident triggered a week-long hospital stay — Peterson suffered a severely damaged kidney and a broken hip and wrist, and doctors performed exploratory surgery — in addition to a two-week absence from school and questions about whether her promising lacrosse future was over before she had a chance to become a rookie starter on the Saints’ nationally ranked squad.

It also left her mother, Catie Meyer, feeling fortunate the injuries weren’t much worse.

“One inch to the left or the right,” Meyer said, “and it would have been a totally different story for Rita.”

After the ATV pinned her to the ground, Peterson remembers, she didn’t cry, scream or make much noise at all. She wriggled from underneath the weight of the vehicle and her three friends. Her memory of what happened next is hazy.

Someone in a golf cart came to help the passengers and took her back to the house. She could hardly move on the couch, so she was driven to Inova Fairfax Hospital, where CT scans and tests revealed what doctors initially thought was a dead kidney, in addition to her fractured hip.

In fact, the ATV had damaged one of Peterson’s renal arteries, but there was still a slight trickle of blood flow to the kidney. The organ only works at about 7 percent now, Meyer said, causing Peterson high blood pressure and looming decisions about how to address the issue for her long-term health.

Peterson has emerged as a starter for the nationally ranked Saints. (Toni L. Sandys/The Washington Post)

During her four days in intensive care, doctors also recognized fluid in Peterson’s pelvis and a rapid increase in white blood cells. They performed exploratory surgery with several incisions in her midsection to ensure no further internal damage to her colon and intestines.

The lengthy hospital stay, which included her 15th birthday Nov. 15, presented natural challenges: Peterson had a “death fear” of the many IV needles she endured, adverse reactions to a strong pain medication and the inability to walk. But perhaps the worst moment came when a doctor told her she would never play lacrosse again because of the risk contact posed to her fully functioning kidney.

Peterson looked at her mom, bursting into tears.

“You have one brain, one heart, one stomach,” Meyer told her daughter. “Now you just have one kidney, and we’re not going to treat it any more special than your other organs.”

Upon leaving the hospital, Peterson worked with her St. Stephen’s/St. Agnes teachers and adviser to catch up in the curriculum. During rehabilitation, Peterson worked with trainer Matt Boyd at Healthy Baller in Rockville. Four times a week, including before school on Wednesdays, Peterson would go to Boyd to strengthen her hip and rebuild her conditioning, eyeing a return to lacrosse for the high school season.

St. Stephen’s/St. Agnes Coach Kathy Jenkins called Peterson, who was still in a cast for her wrist and hadn’t run since the crash, a few days before tryouts and told her she could join junior varsity that spring.

“We weren’t even sure if she was going to play this year,” Jenkins said.

But Peterson, whose mom had also played for Jenkins at St. Stephen’s/St. Agnes, was heartbroken. So she still attended varsity tryouts, and while she couldn’t run the timed mile, she passed other physical abilities assessments and wowed the staff on the field.

“I couldn’t go off my reputation anymore,” Peterson said of her prior success on the club lacrosse circuit. “That was out the window.”

Come the Saints’ opening games on a spring break trip to Georgia, Peterson was on the varsity sideline and available as a substitute. And after teammates endured a few injuries midway through the season, Peterson became a starter.

She still faces obstacles. Peterson has to continue to monitor her heart rate, and doctors have suggested she would need a padded brace to protect her kidney.

But she played every minute during an April 17 win against rival Georgetown Visitation, which had school religious figures praying for Peterson after her accident, and she scored her 14th goal of the season late in the fourth quarter to thwart the Cubs’ comeback attempt.

“No one ever thought I would be playing, much less starting and scoring in a huge game against Visitation,” Peterson said. “I wanted it more than anything in my life.”