Anatomical considerations regarding the posterior interosseous nerve during posterolateral approaches to the proximal part of the radius.
BACKGROUND
The purpose of our study was to quantify the dimensions of a surgically safe zone along the proximal part of the radius, from the posterolateral aspect.


METHODS
The posterolateral approach between the anconeus and the extensor carpi ulnaris was performed in thirty-two cadaveric specimens, and the posterior interosseous nerve was exposed. Forearms were measured from the radial styloid process to the radiocapitellar joint. The distance from the capitellum to the point where the posterior interosseous nerve crossed the radial shaft and the angle between the nerve and the shaft were measured with forearms in pronation and supination.


RESULTS
Pronation of the forearm allowed safe exposure of at least the proximal thirty-eight millimeters of the lateral aspect of the radius, with an average proximal safe zone of 52.0 +/- 7.8 millimeters. Supination decreased this proximal safe zone to as little as twenty-two millimeters and an average of 33.4 +/- 5.7 millimeters. The angle formed by the posterior interosseous nerve and the radial shaft in supination averaged 47.4 +/- 6.8 degrees; this decreased to 27.8 +/- 6.7 degrees with pronation.


CONCLUSIONS
Approaching the lateral aspect of the proximal part of the radius is safest in pronation.
Diliberti
T
T
Department of Orthopaedics, University of California, San Diego 92103, USA.
Botte
M J
MJ
Abrams
R A
RA
D000368:Aged; D004550:Elbow / Q000294:innervation / Q000601:surgery*; D005260:Female; D005542:Forearm / Q000294:innervation*; D006801:Humans; D008297:Male; D019637:Orthopedic Procedures; D011403:Pronation; D011859:Radiography; D011884:Radius / Q000000981:diagnostic imaging / Q000294:innervation*