A 56-year-old man comes to the emergency department due to persistent left wrist pain. While walking his dog 5 hours ago, he fell forward onto the ground and landed on his outstretched hand. Examination shows mild left wrist swelling with preserved range of motion. There is point tenderness over the dorsolateral aspect of the wrist between the tendons of the extensor pollicis longus and extensor pollicis brevis. An x-ray of the left wrist is shown in the image below: This patient is at greatest risk for developing which of the following complications?

Question

A 56-year-old man comes to the emergency department due to persistent left wrist pain.  While walking his dog 5 hours ago, he fell forward onto the ground and landed on his outstretched hand.  Examination shows mild left wrist swelling with preserved range of motion.  There is point tenderness over the dorsolateral aspect of the wrist between the tendons of the extensor pollicis longus and extensor pollicis brevis.  An x-ray of the left wrist is shown in the image below:  This patient is at greatest risk for developing which of the following complications?

Quizplus · Accepted Answer

11ec160b_35f1_c181_9249_9b72976f21f8_MD0001_00 Scaphoid fractures are the most common carpal bone fracture and frequently result from a fall on an outstretched hand that causes direct axial compression or hyperextension of the wrist. A scaphoid fracture should be suspected in any patient with persistent wrist pain and tenderness in the anatomic snuffbox-a shallow, triangular depression at the dorsoradial wrist defined by the following borders: The main blood supply to the scaphoid is provided by the dorsal scaphoid branch of the radial artery; this branch enters near the bone's distal pole and then proceeds in a retrograde manner to provide blood supply to the proximal pole. Because fracture of the scaphoid can easily interrupt this retrograde flow, the fractured scaphoid is at risk for avascular necrosis of the proximal pole and fracture nonunion. (Choice B) Carpal tunnel syndrome is caused by median nerve compression at the wrist within the carpal tunnel. It is mostly commonly nontraumatic in origin, but when it does occur following trauma (eg, fall on an outstretched hand), it is typically due to palmar dislocation of the lunate into the carpal tunnel space. (Choice C) Acute compartment syndrome occurs when increased pressure within a fascial compartment (eg, intracompartmental bleeding, muscle swelling) compromises blood circulation within that space. It typically develops after significant trauma, particularly long bone fractures of the leg or forearm. (Choice D) Dupuytren contracture is a slowly progressive fibroproliferative disease of the palmar fascia. Nodules form on the fascia, eventually resulting in contractures that draw the fingers into flexion. (Choice E) Guyon canal syndrome is caused by compression of the ulnar nerve at the wrist within Guyon canal. It can develop following a fall on an outstretched hand but typically occurs due to fracture of the hook of the hamate, which forms the lateral bony wall of Guyon canal. Educational objective: Fracture of the scaphoid bone may result from a fall on an outstretched hand and should be suspected if examination shows tenderness in the anatomic snuff box. Scaphoid fracture can disrupt retrograde blood supply to the proximal scaphoid, increasing risk of avascular necrosis. __________ References: Fractures in brief: scaphoid fractures. (http://www.ncbi.nlm.nih.gov/pubmed/20162385) Management of scaphoid fractures. (http://www.ncbi.nlm.nih.gov/pubmed/28746289) Posttraumatic avascular necrosis after proximal femur, proximal humerus, talar neck, and scaphoid fractures. (http://www.ncbi.nlm.nih.gov/pubmed/31149969)

A 56-Year-Old Man Comes to the Emergency Department Due to Persistent