48-year-old white male presents to ED 5 days after crush injury at work with a heavy wooden box.  For the past few days he has been experiencing worsening pain, redness and swelling in this right index finger.  His vital signs are stable and he is afebrile.  On examination, you notice fusiform swelling of the digit with erythema and an open wound.  His is holding his finger in a partially flexed position and states it is too painful to extend the digit.  His plain films of the hand are negative for fracture.  You perform a focused ultrasound to assess for the presence of an abscess and a flexor tenosynovitis.

Take the case.