The hip joint creates the jointed connection between the trunk and the legs. It connects the pelvis and thigh bones. It is a ball-and- socket joint which, due to its shape, enables great freedom of movement. It consists of the socket of the hip bone (pelvic bone) and a ball (thigh bone), which is covered with a layer of cartilage.
The joint itself is sealed off by a joint capsule. Within the joint capsule, a mucosa layer produces the synovial fluid, which on the one hand nourishes the cartilage, and on the other hand produces friction free sliding. The synovial fluid also serves as a sort of shock absorber which intercepts the powerful forces that impinge on the joint during a person's lifetime. The bones are connected by the ligaments which impart the necessary stability to the joint. The joint is moved by muscles and tendons.

In principle, Total Hip Replacement or THR is the replacement of the diseased joint by an artificial implant. Many decades ago, the relatively simple structure of the hip joint a ball-and-socket joint had inspired physicians and medical technicians to create an artificial hip, and in the course of time follow-up examinations and improvements in operative methods and materials have led to great progress, and the optimisation of total hip prosthesis.
Thus, we can view THR as a routine operation.

The hip prosthesis is designed to simulate the human anatomy and is comprised of a hip socket and a hip shaft. The ball head which articulates in the socket is placed on the hip shaft. The ball head may be a ceramic or metal head running against a polyethylene socket. The socket can also be entirely of ceramic. The materials used in the joints have been specially developed for medical purpose with good tissue tolerance and allow the function to be as painless and lasting as possible.

The hip is a simple ball-and-socket joint where the thigh bone joins with the pelvis. When these joint surfaces become roughened, causing severe pain and stiffness, the ball-and-socket have to be replaced.
Total hip replacement is when a cup is inserted into the pelvis and fixed into place and a stem with a head attached is inserted into the shaft of

the femur. The artificial ball-and-socket are then fitted together to function as a normal hip joint. For each prosthesis type, there is wide range of models, manufactured in different sizes. Selection of the prosthesis is dictated by the bone condition and the weight and physical activities of the patient. The surgeon will prepare for the operation on your hip with a graphic plan compiled on the basis of X-rays and will thus determine the model, size and position of the prosthesis parts.

Materials used for artificial joints are highly developed. They provide maximum tolerance and long-term acceptance by the human body, which is called bio-compatibility. For decades, Stryker has been a leader in material development and fundamental know-how in metallurgy, material, research and testing. In general, there are three different types of material employed for orthopaedic purposes: Metals, Polymers, Ceramics.