The modified Evans classification is based on the stability affected by fractures in the greater or lesser trochanter:

① Type IA (non-displaced) and Type IB (displaced) are simple fractures with the fracture line running from the outer upper to the inner lower along the intertrochanteric line, which are easy to anatomically reduce and stable after reduction;

② Type IIA fractures involve the greater trochanter, and Type IIB fractures involve the lesser trochanter;

③ Type III fractures involve both the greater and lesser trochanters.

In 1979, Kyle further classified intertrochanteric femur fractures based on the extent and degree of displacement into four types (see table below).