Hip replacement is one of the most common and successful operations performed worldwide. It is generally performed for arthritis, in which the surfaces of the joint become worn, leading to pain and reduced movement. The operation involves creation of a new surface in the socket and providing a new ball for the ‘ball and
socket’ configuration of the hip joint. Many designs exist, and many surface finishes for the interior of the joint. Depending on a variety of factors such as age, quality of bone and activity level the ‘bearing surfaces’ can consist of metal on plastic, ceramic on plastic, ceramic on ceramic, or metal on metal. The socket and stem attached to the ball can be fixed to the bone with or without special ‘bone cement’, depending on bone quality and anticipated activity level.
After the operation patients generally walk the following day under the guidance of a physiotherapist. Discharge from hospital normally occurs 4 or 5 days after surgery, and patients are generally provided with advice about care of their new hip joint. Normal walking (without any trace of a limp) normally returns within 3 months, but until then patients often use a walking stick for support.
After many years some hip replacements wear out and cause pain. Surgeons sometimes recommend that the hip should be ‘revised’ even in the absence of pain if there is concern that surrounding bone may become damaged. Revision is also occasionally recommended if a hip replacement becomes prone to dislocation (jumping out of the socket).
Revision operations take a bit longer than first-time hip replacements, and consequently recovery may take a little longer. Precautions to safeguard the joint in the early months may also need to be a little more strict. Grafting of bone to damaged areas is also occasionally required. The principles of the operation are the same as those for first-time surgery, with the creation of a new ‘ball and socket’ after removal of the old components.
Hip Replacement- See the video...
Conservative Hip Replacement – Short stems and resurfacing
In recent years a number of ‘conservative’ types of artificial hip have emerged. These are intended, in general, for younger active individuals. They have the potential advantage of conserving more bone (leaving as much as possible of the ‘native’ hip behind). This can be important later in life should further surgery be necessary.
In general, two types of ‘conservative’ hip replacement are available – metal-on- metal hip resurfacing and short-stem hip replacement. In hip resurfacing the damaged joint surfaces are skimmed and replaced by a metal coating. This performs well in male patients (who have larger hip joints than females). In short-stem hip replacement (often performed in the smaller hips of females), a short spike of metal is introduced into the thigh bone with a ceramic ball-head on top which articulates with a ceramic interior in the new socket.
The younger individuals who have these ‘conservative’ operations often walk well at an early stage, and they often go home after 3-4 days. Careful follow-up is often recommended to make sure the new joint is performing well.
Hip impingement surgery and hip arthroscopy
In recent years it has become understood that a number of younger individuals experience a collision between the thigh bone and the wall of the hip socket causing pain during or after sport, or even during relatively sedentary activity with the hip flexed. These cases usually require careful evaluation by x-rays and a scan performed after an injection of dye. Surgery can be performed to relieve symptoms from this collision process (known as femoro-acetabular impingement) to trim prominent bone, to repair damage to the joint surfaces and to repair or tidy the rubbery ring surrounding the socket (the labrum) which contains a lot of nerve fibres (and therefore ‘feels’ the pain during collision). ‘Impingement surgery can be performed by key-hole techniques (hip arthroscopy) or by ‘open’ surgery (using traditional methods) depending on the accessibility of the offending damage to the joint. After hip arthroscopy patients usually go home the same day, and after a few weeks they generally walk well. A return to sport can follow within 6 weeks. After ‘open’ surgery recovery is slower and more variable (depending on surgical approach) and sometimes requires a further day-case operation to remove screws. Many younger patients are now undergoing ‘impingement’ surgery, and there is a growing belief that it may prevent wear inside the hip joint later in life.