As a senior resident, I am continually humbled by the practical questions of junior residents that I cannot answer. While practicing ultrasound-guided knee aspiration last week, a resident asked for clarification about a conversation she had had with an Orthopedic surgeon about the suprapatellar bursa. A patient was seen in the Emergency Department with a red, hot, swollen knee, so the usual “rule-out septic joint” workup was initiated. Whether by difficult landmarking or …