Author: Dalton Lohsandt, MD
Co Author #1: Ryan Muehling, MD
Co Author #2: Kevin Clary, MD
Co Author #3: Aaron Gray, MD
Senior Editor: Yaowen Hu, MD, MBA
Editor: Rachel Chamberlain, MD

Patient Presentation:
A 7-year-old male soccer player presents to emergency room with 1-day history of worsening pain in right lower extremity after a fall from his bicycle.

History:
He had difficulty ambulating with swelling in the right knee and ankle but his pain improved with rest. Ibuprofen provided minimal relief and he admits to issues with pain in the right lower extremity for the last two months with no swelling. The symptoms started while playing soccer with no known injury. He had difficulty kicking a ball and a significant limp with weightbearing. He denied right knee catching or giving out.

His review of systems was positive for tactile fevers, poor appetite, and an undefined amount of weight loss causing loose-fitting clothes.

He has past medical history of Hemoglobin E trait. His family history revealed parents from Thailand.

Physical Exam:
General: Well-developed child in no acute distress
Weight 23.2 kg & BMI 16.1
Extremities: Strength testing 5/5 bilaterally. Sensation fully intact. Lower extremity pulses present and equal bilaterally.
Right leg: There was mild swelling around knee but there was no warmth, erythema, or ecchymosis. Moderate tenderness was elicited with palpation over the proximal tibia on the medial and lateral aspects. Passive and active range of motion of hip, knee, and ankle showed no deficits. There was hesitation and moderate pain with knee stability testing, but no instability was noted. His ankle exam was normal except for a small bruise near the medial malleolus.
Left leg: unremarkable
Gait: Unable to assess due to pain with weightbearing on the right lower extremity.

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