Author: Allyson Sanders, MD
Co Author #1: Andrea Evenski, MD
Co Author #2: Aaron Gray, MD
Senior Editor: Justin Mark Young, MD, FAMSSM
Editor: Brittany Telford, MBBCh BAO, MPT
Patient Presentation:
A 12-year-old softball player presented with one month of atraumatic left knee pain and effusion.
History:
A previously healthy 12-year-old female presented with one month of left knee pain and swelling in the absence of trauma or injury. The pain was constant, rated as a 6/10 and localized to the medial joint line and suprapatellar region. It was exacerbated by bending, squatting, kneeling and going up stairs. She continued to play softball, although symptoms worsened after activity. Conservative measures such as ice and NSAIDs provided minimal relief. She also reported mild right medial knee pain and swelling, less significant than the left. Notably, her parents reported that she had a tick bite a few months prior to symptom onset and expressed concern about a possible correlation. She denied fevers, chills, rashes, myalgia, night sweats, and weight loss.
Physical Exam:
Left knee: Large effusion without erythema or warmth. Tenderness over the medial joint line and suprapatellar pouch. Active ROM 0-115. Resisted knee flexion and extension 5/5 when seated on the exam table. No laxity with varus or valgus stress at 0 and 30 degrees of flexion. Negative Lachman's. Negative McMurry's.
Right knee: Trace effusion without erythema or warmth. Tenderness over the medial joint line. Active ROM 0-120. Resisted knee flexion and extension 5/5 when seated on the exam table. No laxity with varus or valgus stress at 0 and 30 degrees of flexion. Negative Lachman's. Negative McMurry's.
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