CHOP doctors tackle aggressive osteosarcoma in an active 7-year-old with chemotherapy and a novel surgery that allows her ankle joint to function as a knee.

Ava, age 6, first complained of left knee pain on Mother’s Day 2023. Her parents, Amy and Paul, thought it was a minor injury from dancing or gymnastics. Doctors found no injury and advised icing and ibuprofen.

Recurring pain leads to a concerning x-ray

Ava’s pain recurred for a week – intense enough to wake her at night. Paul scheduled an appointment with Matthew Grady, MD, FAAP, CAQSM, a pediatric sports medicine specialist at CHOP’s Specialty Care Center in King of Prussia. Ava's leg was x-rayed on a Friday afternoon, almost two weeks after the pain started.

“Everyone thought nothing would come of it,” Paul recalls. But following the initial x-ray, he remembers the care team asking for another x-ray, higher up the leg.

Dr. Grady and CHOP oncologist Charles A. Philips, MD, MSHP, had a devastating discussion. They suspected a malignancy visible on Ava’s femur (thigh bone) indicated osteosarcoma, an aggressive bone cancer that affects around 400 children annually. Osteosarcoma is rare in young children; most cases are diagnosed in adolescence.

Moving quickly toward a novel but agonizing choice

Everything happened fast: an MRI within days, and a bone biopsy shortly after that confirmed the diagnosis. The tumor would need to be removed a few months after starting chemotherapy. Amy and Paul met with another CHOP oncologist, Hiroto “Hiro” Kiguchi, MD, to learn about treatment protocols. Chemotherapy started two weeks later.

Although endoprosthesis and amputation above the knee were options, CHOP orthopedic oncologist Alexandre Arkader, MD, suggested rotationplasty, a reconstructive surgery where a patient’s ankle joint serves as their knee joint. The procedure involves removing the lower femur, knee and a portion of the leg below the knee. The foot is rotated 180 degrees and attached to the lower thigh to create a functioning joint with similar mobility to a below-the-knee amputation. This allows for a natural joint instead of an artificial one. And Ava can remain active with a prosthetic leg.

Dr. Arkader believed rotationplasty would give Ava the best chance at an active lifestyle as she grows. Facing a heart-wrenching decision, Amy and Paul sought second opinions, and talked to parents whose children had undergone rotationplasty surgery.

“We met one of Dr. Arkader’s patients, a year older than Ava,” Amy says. “Just to see her playing on the playground with her prosthesis gave us peace of mind that this was the right call.”

In September 2023, three months after her diagnosis and following two cycles of chemotherapy, Ava had rotationplasty surgery at CHOP’s Hospital on our Philadelphia Campus.

Ava’s go-getter attitude is supported by the Child Life team

How has Ava handled the challenges? “We are amazed by her,” Paul says. He recalls that the day after surgery, “she was already in physical therapy, wanting to get mobile.” She returned to school a week later.

Amy and Paul credit members of CHOP’s Child Life team – Kristen Lumley and Samantha Couto – along with social worker Chelsea Hackman, MSW, LSW, and psychologist Colleen Cadigan, PsyD, for supporting not just Ava, but the whole family, including 9-year-old Andrew, Ava’s older brother and best friend.

“Kristen made Ava a rotationplasty Barbie, so she could see what it would look like,” Amy said. “When treatment is over, I’ll be sad because this team feels like family at this point.”

After Ava’s tumor was removed, an analysis of the tumor showed a high necrosis rate, indicating chemotherapy has had a positive effect. She continues to receive outpatient chemo at the King of Prussia campus. With her prosthesis, Ava has begun her gait training with the use of a walker. Going forward, she’ll have regular scans to monitor her progress against her original sarcoma diagnosis.

“We got snow recently, and she grabbed her walker and went out on our deck to start making a snowman,” Amy says. “She’s a go-getter, and I love that about her.”