Author: Miriam Reece, MD
Co Author #1: Eric Groce, DO
A 15 year-old male football player presented with persistent swelling, pain, and mechanical symptoms in his left knee after a skateboarding injury three weeks prior to presentation.
While skateboarding the patient fell and landed on the anterior aspect of his flexed left knee. He reported immediate pain and swelling. He has been taking Ibuprofen 600mg three times daily as needed with moderate relief. The patient also took two weeks off from football. Feeling better, the patient then resumed practicing football and noticed swelling and posterior knee pain with activity, especially running. Subjective sensations of locking and instability were described. He stated he fell once due to knee instability. Pertinent past history is a prior traumatic injury to his left knee four years ago with negative radiographic films and a complete recovery. The patient was otherwise well.
The patient had a normal stance, arches, and gait. Inspection revealed obvious soft tissue swelling surrounding the left knee. No skin rashes, erythema, ecchymosis, nor increased warmth was appreciated. Normal distal pulses bilaterally. Full range of motion in bilateral lower extremities except for limited left knee flexion found at end range of motion. Strength normal bilaterally, but mild pain elicited on active left knee flexion. Right knee had normal ligamentous and meniscal testing. The left knee had a moderate joint effusion, no joint line tenderness, and no abnormalities in patellar testing; including Clark's sign and patellar tracking. Ligamentous testing of the left knee revealed normal varus and valgus testing, negative Lachman's, and a positive posterior drawer sign. Negative posterior sag test. Slight discomfort found with McMurray's but no mechanical symptoms.
Click here to continue. Challenge yourself by writing down a broad differential diagnosis before moving to the next slide.