Hip replacement
Generally aimed at patients with more advanced signs of arthritis, a traditional total hip replacement (THR) consists of a surgical procedure in which parts of an arthritic or damaged joint are removed and replaced. The resultant artificial joint is designed to move just like a healthy hip.
In a THR, the head of the femur (thigh bone) and the acetabulum (hip socket) are both replaced. The metal stem of the new hip is implanted into the damaged portion of the femur. The femoral head is replaced with an artificial ball at the top of the femur, attached to the metal stem, typically made of metal or ceramic. The hip socket (into which the ball fits) is covered with an artificial liner made of ceramic, polyethylene (a durable, wear-resistant plastic) or metal, backed with a metal shell such as Corin’s Trinity. These surfaces are known as ‘bearings’. The liner allows for smooth and painless movement of the ball in the socket.
The artificial joint may be cemented in position or press-fit securely in place without cement. In a ‘cementless’ fixation, the surface of the implant is covered in a special coral-like coating. Over time, the patient’s natural bone grows through the pores of the coating, attaching the artificial joint to the hip’s natural remaining bone structure.
Cemented THRs, such as Corin’s TaperFit, are most suitable for elderly patients with low functional demand. Hybrid THRs combine the use of a cemented femoral stem with an uncemented acetabular cup. These can suit elderly and still active patients – providing a choice for higher wearing and more stable bearings, giving improved function over traditional cemented replacements. Uncemented implants, such as Corin’s MetaFix, support a more active lifestyle and are used in patients from their late teens through to late eighties.
The length of stem used in THR also varies. Traditional stems are longer, sitting further down inside the femur. These types of implant are very well established and have been in use for many years. However shorter stems, such as Corin’s MiniHip, have also come into use in recent years, offering a more bone conserving option. These provide a solution for today’s more active, demanding patients, particularly those who are at risk of requiring more than one hip joint replacement over the course of their lifetime.
THR has been demonstrated to be a successful procedure. It is commonplace in terms of the numbers of operations carried out and as reported by the National Joint Registry (NJR)1, around 65,000 hip replacements are conducted in the UK each year – around 200 every working day.
1. National Joint Registry (NJR|) 6th Annual Report.
Important: The information and guidance provided here is general in nature and should not be considered as medical advice in any way. You should always seek detailed advice from a qualified medical practitioner.
