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Every year thousands of New Zealanders benefit from a hip replacement. This is an operation to remove a severely impaired hip joint and replace it with an artificial joint or prosthesis. The most common reason for performing a hip replacement is to relieve pain and the  disability of severe arthritis in the joint.

The concept was pioneered by an orthopaedic surgeon, Sir John Charnley, who worked with engineers to develop the techniques and materials used in hip joint replacement.  
Patients present to their General Practitioner with pain and stiffness. In assessing the severity of the damage to the hip and whether or not a patient reaches the threshold for a hip replacement, a number of investigations are undertaken by the GP.

This includes a physical examination, a thorough medical history, blood tests and an X-ray. It is common for the patient to complete what is called the “Oxford Hip Score” questionnaire. This is short questionnaire which sets out key questions in relation to pain and mobility.  Combined with the other medical information obtained, the information assists the General Practitioner with an indication of the severity of the damage to the hip joint and whether or not a referral to an orthopaedic specialist is required.

The primary reason for requiring a hip replacement relates to arthritis and how it damages the cartilage in the joint. Healthy hips have a smooth cartilage which covers the ends of the femur as well as the socket in the pelvis into which the ball end of the femur fits.The cartilage acts as a cushion and allows the ball to glide easily into the socket. Osteoarthritis is the most common form of arthritis. It is estimated that over 300,000 New Zealanders are living with the condition. Osteoarthritis can occur at any time of life but the incidence increases with age. It usually affects people over 40 years of age. Approximately half of people over 60  are affected in at least one joint. Virtually all people over the age of 80 years suffer from osteoarthritis to some extent. Rheumatoid arthritis can also damage the joint as can other diseases or injury.
Treatment for severe damage to the hip is a hip replacement. Other recommendations include maintaining healthy body weight, exercise and seeking advice  from physiotherapists to improve mobility, increase muscle strength and decrease pain. Medications also play a role in the management of pain caused by osteoarthritis.
Patients who have a total hip replacement are likely to experience significant pain relief, increased mobility and a return to a more normal and independent life