One hundred fifty-three impacted femoral neck fractures were studied to define the usual initial displacement of these fractures. The average fracture had a Pauwel's angle of 41°, was in valgus, and was only minimally displaced on the lateral view.
All fractures that were either inherently stable or internally fixed healed without incident. However, seven fractures with high Pauwel's angles displaced under conservative management. Statistical analysis confirmed the correlation of fracture stability and Pauwel's angle.
Our incidence of avascular necrosis was 16.9%. Extreme valgus displacement correlated with the occurrence of avascular necrosis.
Bunata RE, Fahey JJ, Drennan DB. Factors Influencing Stability and Necrosis of Impacted Femoral Neck Fractures. JAMA. 1973;223(1):41-44. doi:10.1001/jama.1973.03220010027006