Normal Anatomy of the Hip joint

The thigh bone, femur, and the pelvis, acetabulum, join to form the hip joint. The hip joint is a "ball and socket" joint. The "ball" is the head of the femur, or thigh bone, and the "socket" is the cup shaped acetabulum.

The joint surface is covered by a smooth articular surface that allows pain free movement in the joint.

The cartilage cushions the joint and allows the bones to move on each other with smooth movements. This cartilage does not show up on X-ray, therefore you can see a "joint space" between the femoral head and acetabular socket.


The pelvis is a large, flattened, irregularly shaped bone, constricted in the center and expanded above and below. It consists of three parts: the ilium, ischium, and pubis.

The socket, acetabulum, is situated on the outer surface of the bone and joins to the head of the femur to form the hip joint.


The femur is the longest bone in the skeleton. It joins to the pelvis, acetabulum, to form the hip joint.

How does the Hip joint work?

Find out more in this web based movie.

Femoro Acetabular Impingement (FAI)

Femoroacetabular impingement (FAI) is a condition where there is too much friction in the hip joint from bony irregularities causing pain and decreased range of hip motion.

Hip Arthroscopy

Arthroscopy, also referred to as keyhole or minimally invasive surgery, is a procedure in which an arthroscope is inserted into a joint to check for any damage and repair it simultaneously.

Total Hip Replacement (THR)

Total hip replacement is a surgical procedure in which the damaged cartilage and bone is removed from the hip joint and replaced with artificial components.

Hip Resurfacing

The hip joint is also known as a ball and socket joint, where the ball (femoral head) of the thigh bone fits into the socket (acetabulum) of the pelvis bone.

Revision Hip Replacement

Revision hip replacement is a complex surgical procedure in which all or part of a previously implanted hip-joint is replaced with a new artificial hip-joint.

Click on the topics below to find out more from the orthopedic connection website of American Academy of Orthopaedic Surgeons.