Due to the swelling, we obtained an in-office ultrasound which showed a significant effusion in the suprapatellar pouch. Case Photo #5 We aspirated 48cc of clear, straw colored, non-purulent fluid. This fluid was collected and sent for culture, which remained in the lab for 3 weeks without the growth of any organisms.
In-office X-rays were obtained which showed well preserved joint spaces, normal bony alignment, and no fractures or masses seen.
Case Photo #2 Case Photo #3 Case Photo #4
MRI was obtained two weeks after initial aspiration and conservative treatment, due to reaccumulating fluid and additional pain. MRI showed a large joint effusion with a 3.8cm x 2.4cm x 2.5cm mass-like lesion that indented the posterior-superior margin of Hoffas fat pad and extended posterior to the lower pole of the patella. Case Photo #6 Case Photo #7 Case Photo #8
Due to high suspicion of our working diagnosis, patient was referred to Orthopedic Oncology.
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