Author: Mark Carrasco, MD, MPH
Co Author #1: Matthew Heath Hale, MD
Co Author #2: Ian McKeag, MD
Co Author #3: Irfan M. Asif, MD, FAMSSM
Senior Editor: Drew Duerson, MD
Editor: Naga Sai Venkata Madhavapeddi, MD

Patient Presentation:
An 18-year-old male collegiate basketball player with no past medical history presented to the training room for right lower extremity pain.

History:
Pain was described as throbbing, intermittent and localized to the right lateral thigh without radiation. He also reported thigh swelling. Pain worsened with basketball activities and improved with rest. He saw the Sports Medicine team one week prior for similar pain along with right knee pain and swelling. The symptoms occurred after he was accidentally kneed during practice. Point of care ultrasound of the region showed fluid within the right suprapatellar pouch and 10 cc of sanguinous fluid was subsequently aspirated from the region. He was diagnosed with a quadriceps hematoma and instructed to take indomethacin for pain control. The swelling improved a few days later at follow-up. Pain prevented him from playing any games to that point in the season. He had a history of a similar episode 3 years ago which took 8 weeks to resolve. At the time of presentation, the athlete denied paresthesias, erythema or warmth of the region. He denied fevers.
The patient denied any additional bleeding episodes or any family history of bleeding disorders. After initial lab work was largely inconclusive, testing was expanded to include Factor XI (FXI), Factor IX (FIX), and Fibrinogen.

Physical Exam:
Right Lower Extremity:
Inspection: Slight swelling over the antero-lateral thigh. Mild effusion in the suprapatellar recess. No erythema, ecchymosis, or skin lesions.
No tenderness to palpation along the medial or lateral knee joint lines
Range of motion was from 0 to 90 degrees of knee flexion limited by quadricep pain.
Extensor mechanism intact.
Stable to varus and valgus stress testing at 0 and 30 degrees, negative Lachman test, negative posterior drawer, negative McMurray.

Neurovascularly intact in the lower extremity

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