SplintER Series: Don’t forget about the (tibial) spine!
A 13-year-old patient presents to the Emergency Department after sustaining a twisting knee injury while playing soccer. There was a pop, and the patient was subsequently unable to bear weight due to pain and knee instability. The swelling and pain increased in the hours after the injury occurred. On examination, there is a large knee effusion and a positive Lachman test. You obtain imaging (Figure 1). What is your suspected diagnosis? What is your initial workup in the ED? What imaging confirms the diagnosis? What is your management and disposition?

Figure 1: AP and lateral radiographs of the left knee. Case courtesy Dr. Jeremy Jones, Radiopaedia.org, rID: 27372