At just 4 years old, Levi Moser found himself with a serious injury.

In May 2018, he tore his posterior cruciate ligament (PCL) — the ligament that connects the thigh bone to the shin bone — and his meniscus — the cartilage in the knee that absorbs shock between the two bones — during a trip to a local trampoline park.

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After undergoing surgery with Eileen Crawford, M.D., an assistant professor of orthopaedic surgery and sports medicine at C.S. Mott Children's Hospital, Moser needed to start physical therapy.

Levi was referred to the Michigan Medicine Comprehensive Musculoskeletal Center at the Brighton Center for Specialty Care.

"We would drive from the East Lansing area to Brighton twice a week for Levi's hour-long appointments where he would start learning how to walk on it again," says Natalie Moser, Levi's mom.

From training wheels to two wheels

Levi spent two months in a full leg cast followed by an adjustable leg brace that he was able to take off when he started kindergarten in the fall.

"After he was done with the cast, he had no muscle in his little injured leg and it was half the size of his healthy one," Moser says.

Levi started working on his mobility again with physical therapist assistants, Alli Rauch and Stacey Ostrowski.

"At first, Levi seemed pretty nervous about physical therapy," Rauch says. "Because of his age and small nature, Stacey and I had to get creative with his exercises.

"Once he gained enough strength and range of motion to discontinue his brace, we created obstacle courses for him to keep engaged and work on functional movement patterns to bend his knee."

"He loved working with Alli and Stacey and was always excited for his appointments to show them what new things he could do," Moser says.

"Because he was one of the youngest patients to have this injury, they did a great job thinking about how to engage him and keep him on the right therapy path."

One therapy exercise, in particular, had Levi ready to keep practicing at home.

"They had a kid's training wheel bike that he would ride around the clinic," Moser says. "To watch him progress from barely able to push the pedals to having us barely able to keep up with him while he was riding it was awesome."

Ostrowski adds, "Each time Levi would ride the bike in the gym, we would give him new goals and courses to follow.

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"We worked not only on his leg strength, but also on balance with starts and stops and weaving in and out of cones," she says. "He always looked forward to having challenges and achieving them, as well as trying to go faster as we jogged alongside encouraging him."

And riding that bicycle so often led to a new milestone.

"Just a few weeks ago he was able to take the training wheels off of his bike at home," Moser says.

Back to activities

After a few months of therapy sessions, Moser, now 5 years old, was cleared to fully re-engage in activities in March.

"He started tennis lessons in May and has been doing swim lessons and a boys' dance class," Moser says. "When he couldn't do anything physical yet, we started him in piano lessons and that's been fun to watch, too."

Moser says Levi still asks about his friends Alli and Stacey.

"We're so thankful for them and he asks about them all the time!" she says.

Levi will still see Crawford for regular check-ups and to see how everything is progressing until he's fully grown.