A rural physician assistant in a medically isolated region m…
A rural physician assistant in a medically isolated region meets a 45-year-old male with a right hand deformity. He explains the condition set in gradually over a period of several months after he “broke his elbow” falling off his roof. The PA immediately recognizes this classic claw hand appearance in which digits 4 and 5 are hyperextended at the MCP joint and flexed at the PIP joint He has the ability to flex and extend digits 1-3, but cannot fully extend digits 4 and 5. The hypothenar eminence is flattened from muscular atrophy, but the thenar eminence is well maintained. Which one of the following nerves was most likely injured?