A 36-year-old construction worker arrives at the emergency room after falling three meters (ten feet) off a ladder. The patient braced his fall with outstretched hands and instantly felt significant pain in his left wrist upon striking the ground. The left wrist is swollen, but there are no lacerations. There is a robust radial pulse and the fingers are fully perfused. A palpable lump is located directly proximal to the left palm. As seen in the exhibit, an X-ray of the left wrist demonstrates a lunate dislocation with no sign of a distal radius fracture. The patient is at greatest risk for impairment of which of the following hand functions?

Question

A 36-year-old construction worker arrives at the emergency room after falling three meters (ten feet) off a ladder. The patient braced his fall with outstretched hands and instantly felt significant pain in his left wrist upon striking the ground. The left wrist is swollen, but there are no lacerations. There is a robust radial pulse and the fingers are fully perfused. A palpable lump is located directly proximal to the left palm. As seen in the exhibit, an X-ray of the left wrist demonstrates a lunate dislocation with no sign of a distal radius fracture.   The patient is at greatest risk for impairment of which of the following hand functions?

Quizplus · Accepted Answer

Eductional Objective: A volar displacement of the lunate from its usual position inside the carpal tunnel floor can result in median nerve compression and/or damage. A medial nerve damage at the carpal tunnel level can cause weakness in thumb abduction, flexion, and opposition.

A 36-Year-Old Construction Worker Arrives at the Emergency Room After