In hip joint replacement surgery, the hip socket is fitted with Ultra highmolecular weight high-density polyethylene cup, and the head of femur (thighbone) is replaced with a metallic ball. This joint functions efficiently as a normal joint, giving the patient stability as well as mobility.

According to how these parts are fixed to the bone, hip joint replacement is classified as :

• Cemented :
  In this design, the parts are fitted to the patient bone with a substance called bone cement. The correct name for it is Poly Methyl Methacrylate. This design is still more commonly used.
• Non cemented :
  In this design, the parts are pressfit in the prepared bone and the bone is expected to grow in the fine crevices of the implant. This design is mainly used for younger individuals.

NON CEMENTED HIP JOINT REPLACEMENT Indicated in young patient with arthritis. Young patients who develop hip arthritis due to any cause, and are unable to walk, or walk with great difficulty now have a good solution to their painful hips. The new designs of hip implants do not require fixation with bone cement, last for longer period of time and eliminate pain.