Author: Tama Fukuyama, MS
Co Author #1: Justin Young, MD
Co Author #2: Roxana Hu, BS
Senior Editor: Heather Rainey, MD
Editor: Reina Nakamura, DO

Patient Presentation:
A 37-year-old female hiker presented to a sports medicine clinic with worsening right knee pain that began 2-months ago after she slipped and fell while on a hike consisting of many stairs.

History:
Prior to this incident, she had completed two relatively easy hikes (around 2 miles each) and reported a significant amount of pain and swelling following each hike. These symptoms were unexpected, as she typically completes 20+ mile hikes with no issue. She did not note any recent trauma or crepitus during hiking. The only incident during which she reports feeling a "pop" was over ten years ago while skiing. She had her foot amputated at age four due to a congenital defect of the foot. On follow-up one month later, she reported improvement to her right knee pain and swelling, with no pain at rest, no additional falls, and resumption of light activity including completing partial hikes.

Physical Exam:
Vitals: 5'2", 121 lbs. Right Knee Exam: Below knee amputation, right foot prosthesis. Right knee range of motion with flexion and extension to 135/-5 degrees. Trace effusion was noted. Positive patellar compression test for pain and increased lateral patellar glide. No ligamentous laxity to varus and valgus (30 degrees) stress testing. Positive Lachman's testing. Positive anterior drawer. Negative posterior drawer. Medial joint line tenderness. Positive McMurray's. There was no patellar tendon tenderness, pes anserine bursa tenderness, or distal iliotibial band tenderness. The patient is otherwise neurovascularly intact.

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