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Updated: Jun 16, 2026

Tissue Collection and RNA Extraction from the Human Osteoarthritic Knee Joint
Published on: July 22, 2021
A medial soft-tissue mass of the knee
1Department of Radiology, University of Michigan Medical Center, Ann Arbor, MI, 48109-0326, USA.
Abstract:
A 46-year-old man presented to a sports medicine clinic with medial left knee swelling that had begun 2 months earlier after a direct blow from a fall. The patient complained of stiffness and discomfort that occurred with immobilization and resolved with stretching and exercise. He reported no locking or instability. A physical examination showed marked swelling over the medial knee joint line; the area was firm, rubbery, and nontender. There was no suprapatellar effusion. The patient's knee had a full range of motion, and hamstring and quadriceps strength was normal. Magnetic resonance imaging (MRI) was ordered to exclude a soft-tissue tumor.
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