The femur or thigh bone is the strongest and longest bone of the body and about 45 cm long in an average man that means approximately one fourth of the height of individual. It has upper end, lower end and a cylindrical shaft. Upper end consists of head, neck. The neck is about 5 cm long, connects the head to the shaft and is directed upward, medially and slightly forward and making an angle about 125 with shaft but the angle is wider in children. The neck-shaft angle (NSA ) is defined as the angle formed by the neck axis and long axis of the shaft of femur.The knowledge of the neck shaft angle is valuable in the diagnosis and treatment of fracture of upper end of femur.

The aim of the study is :

1. to evaluate the normal values of femoral neck-shaft angle
2. to detect factors that may affect this angle as age, and sex, in Egyptian adults from Sohag.

Inclusion Criteria:

• Adults, eligible and adequate imaging data for measurement, and absence of fracture, arthritis, tumor, deformity, or surgery on the proximal part of the femur or any disorder that may affect measurements of femoral neck-shaft angle

Exclusion Criteria:

• Adults with incomplete imaging data; and fracture, arthritis, tumor, deformity, or surgery on the proximal part of the femur

Participants who underwent computed tomography (CT) of the femur and acetabulum in departments of Radiology in Sohag University Hospital