AO Principles
In 1958, the AO formulated four basic principles, which have
become the guidelines for internal fixation.
1
They are:
Anatomic reduction
Precontoured plate assists in reduction of metaphysis to
diaphysis and facilitates restoration of length and rotation.
Stable fixation
Locking screws create a fixed-angle construct providing
angular stability.
Preservation of blood supply
Tapered end facilitates submuscular plate insertion. Submus-
cular insertion may help to preserve tissue viability.
Early, active mobilization
Early mobilization per standard AO technique creates an
environment for bone healing, expediting a return to optimal
function.
4
Synthes
Titanium Trochanteric Fixation Nail System—Screw Option Technique Guide
1. M.E. Müller, M. Allgöwer, R. Schneider, and H. Willenegger,
Manual of
Internal Fixation
, 3rd Edition. Berlin: Springer-Verlag, 1991.
2. M. Baumgaertner, S. Curtin, D. Lindskog. “Intramedullary Versus
Extramedullary Fixation for the Treatment of Intertrochanteric Hip Fractures.”
Clinical Orthopaedics and Related Research,
348, pp 87-94, 1998.
3. D. Hardy, P. Descamps, P. Krallis, et al. “Use of an Intramedullary Hip-Screw
Compared with a Compression Hip-Screw with a Plate for Intertrochanteric
Femoral Fractures.”
The Journal of Bone and Joint Surgery,
80-A(5),
pp 618-630, 1998.
