PERCUTANEOUS KIRSCHNER WIRE FIXATION THROUGH THE SNUFF BOX - AN ANATOMIC STUDY

We undertook this study to better define the anatomy of the radial asp ect of the wrist and to establish a zone of safety for the placement o f Kirschner wires, cannulated screws, and arthroscopes within the anat omic snuff box. Twenty fresh frozen cadaver upper extremities underwen t placement of three percutaneous Kirschner wires under fluoroscopic g uidance through the anatomic snuff box. In each extremity, one Kirschn er wire was placed into the radial styloid, one across the scaphocapit ate joint, and one across the scapholunate joint. A safe zone of mean 0.68 sq cm was found deep to the subcutaneous tissue bordered by the r adial styloid, the first dorsal compartment, the radial artery, and th e superficial radial nerve. Kirschner wires placed distal, dorsal, or palmar to the borders of the safe zone were at great risk of injuring neurovascular structures. To minimize the risk of injury to adjacent s tructures, we advise a limited incision in the safe zone with blunt di ssection to the wrist capsule. Though improved anatomic understanding, we established a new location for the arthroscopic 1,2 portal within the snuff box.