- Discussion:
- involves creating an oblique osteotomy of the distal fragment (valgus osteotomy) to obtain stability in unstable intertroch frx;
- this osteotomy changes frx plane from verticle to near horizontal & creates contact between the medial and posterior cortex of proximal and distal fragments;
- goal is too obtain medial stability;
- advantage of this valgus osteotomy is that valgus realignment of proximal fragment makes up for less of length at ostetomy site so that limb lengths remain equal;
- Technique:
- a 45 deg oblique osteotomy of distal frag begins just below flare of greater trochanter and crosses distally and medially to exit about 1 cm distal to apex of fracture;
- if osteotmy is made too transverse it places head in exaggerated valgus position;
- this results in leg's being too long or hip's being unstable;
- excess valgus may incr joint reactive forces and incr DJD;
- to avoid this, the medial end of the osteotomy should exit 1 cm below frx surface medially to compensate for incr length caused by valgus osteotomy;
- guide wire & then implant are inserted at 90 deg to plane of frx of the proximal fragment;
- w/ more vertical alignment of frx, insert guide pin so that it ends up more inferiorly in the femoral head (otherwise, the osteotomy will be placed in varus;
- note, however, the guide pin must still enter center of femoral head;
- insert 135 sliding screw in usual manner;
- frx is reduced and impacted;
- medial cortical opposition and, hence, stability are restored;
- Pitfalls:
- avoid creating an external rotation deformity which would place the shaft in slight internal rotation;
- w/ severe medial comminution, even a valgus osteotomy may not create enough bony contact to ensure stability
The unstable intertrochanteric fracture: treatment with a valgus osteotomy and I-beam nail plate. A preliminary report of one hundred cases.