Dynamic hip screw or Sliding Screw Fixation is a type of orthopaedic

Orthopedic surgery

Orthopedic surgery or orthopedics is the branch of surgery concerned with conditions involving the musculoskeletal system...

 implant designed for fixation of certain types of intertrochanteric and subtrochanteric fractures which allows controlled dynamic sliding of the femoral head

Femur head

The femur head is the highest part of the thigh bone . It is supported by the neck of the femur.The head is globular and forms rather more than a hemisphere, is directed upward, medialward, and a little forward, the greater part of its convexity being above and in front.Its surface is smooth,...

component along the construct. The idea behind the dynamic compression is that the femoral head component is allowed to move along one plane; since bone responds to dynamic stresses, the native femur may undergo remodeling and proper fracture healing.