The cadaveric anatomy of the distal radius: implications for the use of volar plates

Abstract

INTRODUCTION Fractures of the distal radius are common upper limb injuries, representing a substantial proportion of the trauma workload in orthopaedic units. With ever increasing advancements in implant technology, operative intervention is becoming more frequent. As growing numbers of surgeons are performing operative fixation of distal radial fractures, an accurate understanding of the relevant surgical anatomy is paramount. The flexor carpi radialis (FCR) tendon forms the cornerstone of the Henry approach to the volar cortex of the distal radius. A number of key neurovascular structures around the wrist are potentially at risk during this approach, especially when the FCR is mobilised and placed under retractors. METHODS In order to clarify the safe margins of the FCR approach, ten fresh frozen human cadaver limbs were dissected. The location of the radial artery, the median nerve, the palmar cutaneous branch of the median nerve and the superficial branch nerve were measured with respect to the FCR tendon. Measurements were taken on a centre-to-centre basis in the coronal plane at the watershed level. In addition, the distances between the tendons of brachioradialis, abductor pollicis longus and flexor pollicis longus, and the radial artery and median nerve were measured to create a complete picture of the anatomy of the FCR approach to the distal radius. RESULTS The structure most at risk was the palmar cutaneous branch of the median nerve. It was located on average 3.4mm from the FCR tendon. The radial artery and the main trunk of the median nerve were located 7.8mm and 8.9mm from the tendon. The superficial branch of the radial nerve was 24.4mm from the FCR tendon and 11.1mm from the brachioradialis tendon. CONCLUSIONS Operative intervention is not without complication. We believe a more accurate understanding of the surgical anatomy is key to the prevention of neurovascular damage arising from the surgical management of distal radial fractures.