March 21, 2016Health Library
Whether you have just begun exploring treatment options or have
already decided to undergo hip replacement surgery, this information
will help you understand the beneﬁts and limitations of total hip
replacement. This booklet describes how a normal hip works, the
causes of hip pain, what to expect from hip replacement surgery, and
what exercises and activities will help restore your mobility and
strength, and enable you to return to everyday activities.
ANATOMY OF THE HIP
The hip is one of the body’s largest joints. It is a ball-and-socket joint. The
socket is formed by the acetabulum, which is part of the large pelvis
bone. The ball is the femoral head, which is the upper end of the femur
The bone surfaces of the ball and socket are covered with articular
cartilage, a smooth tissue that enables them to move easily.
A thin tissue called synovial membrane surrounds the hip joint. In a
healthy hip, this membrane makes a small amount of ﬂuid that
lubricates the cartilage and eliminates almost all friction during hip
Bands of tissue (called ligaments & the hip capsule) connect the ball to
the socket and provide stability to the joint.
COMMON CAUSES OF HIP PAIN
The most common cause of chronic hip pain and disability is arthritis.
Osteoarthritis, rheumatoid arthritis, and traumatic arthritis are the
most common forms of this disease.
Osteoarthritis. This is an age-related “wear and tear” type of arthritis. It
usually occurs in people 50 years of age and older and often in
individuals with a family history of arthritis. The cartilage cushioning
the bones of the hip wears away. The bones then rub against each
other, causing hip pain and stiffness. Osteoarthritis may also be
caused or accelerated by subtle irregularities in how the hip
developed in childhood.
HEALTHY HIP JOINT
HEALTHY HIP JOINT
Rheumatoid arthritis. This is an autoimmune disease in which the
synovial membrane becomes inﬂamed and thickened. This chronic
inﬂammation can damage the cartilage, leading to pain and
stiffness. Rheumatoid arthritis is the most common type of a group of
disorders termed “inﬂammatory arthritis.”
This can follow a serious hip
injury or fracture. The cartilage
may become damaged and
lead to hip pain and stiffness
Avascular necrosis. An injury to the hip, such as a dislocation or
fracture, may limit the blood supply to the femoral head. This is
called avascular necrosis (also commonly referred to as
“osteonecrosis”). The lack of blood may cause the surface of the
bone to collapse, and arthritis will result. Some diseases can also
cause avascular necrosis.
Childhood hip disease. Some infants and children have hip
problems. Even though the problems are successfully treated during
childhood, they may still cause arthritis later on in life. This happens
because the hip may not grow normally, and the joint surfaces are