The results and the related conditions of 250 undisplaced femoral neck
fractures managed by percutaneous Knowles pinning were evaluated. All
of the patients were over 59 years old, and the protocol of managemen
t and follow-up was determined prospectively. The duration from injury
to management was 3.0 (range 1-12) days, the operation time was 20 (r
ange 10-44) min, and most of the patients were discharged without hosp
italization. The follow-up period was 74 (range 24-138) months. The fi
nal results showed 226 (90.4%) fractures with smooth course of union (
mean union time: 24 weeks), 15 (6.0%) fractures with nonunion, and 9 (
3.6%) fractures with implant problems. Eighteen (7.2%) hips developed
avascular necrosis of femoral head after union. The analysis showed th
at the rate of complications was higher in elderly persons with undisp
laced femoral neck fractures.