Author: Jacob Stelter, MD
Co Author #1: Christopher Hogrefe, MD
Editor: Yaowen Hu, MD, MBA
Senior Editor: Kristine Karlson MD
The patient is a 24 year old female who presents to the Emergency Department for sudden onset of right knee pain.
The patient is a 24 year old female who presents to the Emergency Department (ED) for acute onset of right knee pain. She was visiting Chicago from New York and, just prior to coming to the ED, she developed sudden right lateral knee pain while getting into a car. She was concerned that she may have dislocated her patella and noted difficulty flexing her knee. She rated her pain an 8 out of 10, worse when trying to range her knee or ambulate. Her past medical history included a prior right patellar subluxation, a right medial meniscal tear 14 years prior and a right shoulder labral repair. She denied any numbness, tingling or weakness in her extremities, fever, abdominal pain, or any other symptoms or injuries.
Vitals: Temp 98.1 F, HR 80, BP 154/60, RR 18, Pulse Ox 99%.
General: Awake, alert, in pain
Head, Eye, Ear, Nose, Throat: No signs of trauma, normal oropharynx, normal pupils
Cardiopulmonary: Regular rate and rhythm, no murmur, lungs clear bilaterally
Abdomen: No distention or tenderness to palpation.
Back: No midline spinal tenderness to palpation
Musculoskeletal: Right knee held at 90 degrees of flexion, mild joint effusion. Tenderness along lateral joint line, range of motion limited from 80 to 100 degrees. Further motion not possible due to pain and an apparent mechanical block. The patella tracked appropriately and the extensor mechanism was intact. McMurray's produced pain and sensation was normal to bilateral lower extremities. Anterior and posterior drawer testing were negative. Lachman's, varus and valgus stress testing were not possible due to pain and limited mobility.
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