The best method of treating a supracondylar fracture of the humerus in a child that is unstable when the elbow is flexed to 90 degrees is:

C. Percutaneous pinning.

DISCUSSION: Best results with this fracture are obtained with percutaneous pinning. Hyperflexion of the elbow usually achieves stability but incurs the risk of occluding arterial inflow and may cause permanent neuromuscular deficit. Open reduction is not indicated unless the fracture is irreducible or associated with a vascular injury