Our joints, particularly those to be found in the body’s lower limbs, are subjected to repeated stresses and strains during the average lifetime, and yet, with care, would generally remain functional. However, improved nutrition and healthcare have led to increased longevity and, with it, a marked increase in the need for knee surgery.
Archaeological evidence suggests that simple orthopaedic interventions have been undertaken since prehistoric times. However, until relatively recently, the efforts of these bone doctors were focussed exclusively on the treatment of fractures and dislocations and attempts to correct various skeletal deformities in children. That said, even today, traumatic injuries remain one of the main reasons for a surgeon to decide to operate on this complex articulation between the femur and the tibia. A torn ligament or meniscus will invariably lead to a need for knee surgery and are injuries that are frequently experienced by athletes and by anyone who regularly participates in sport or strenuous exercise.
Where once the surgical treatment of these and similar conditions would have required the joint to be fully exposed, the development of a simple diagnostic tool has since made such drastic measures unnecessary. The device in question is an arthroscope and consists of a narrow-bore tube fitted with a miniature TV camera and a source of illumination that is inserted into the joint via a small incision. If the findings indicate it, knee surgery can be performed using the TV image to guide the necessary instruments that are inserted through an additional tiny incision or two.
Sometimes, a disease process may lead to an accumulation of bone and cartilage fragments inside the joint. This, in turn, creates friction, which causes pain upon movement and can result in further erosion of the connective tissues in the affected joint. Arthroscopy provides the surgeon with a quick means to locate these potentially damaging fragments and to remedy the problem using a simple irrigation technique to remove the residue, and so, avoid the need to perform more radical knee surgery.
Not all joint damage is the result of trauma, however. As mentioned earlier, continuous wear and tear on a joint can also create problems. The condition known as osteoarthritis is a typical example of this. Whereas this condition was typically confined to the elderly, it is now frequently encountered in patients of working age. The condition is characterised by the erosion of the protective cartilage layer that covers the articulating surfaces of the bones. Most often, it affects a knee and surgery will eventually prove necessary.
There is mounting evidence to suggest that the increased frequency of osteoarthritis among younger subjects may derive from the visible increase in obesity in today’s society. While diet and exercise can help to reduce discomfort and slow its progression, first painkillers and later, steroids are eventually necessary to manage the symptoms. When these are no longer effective, the only remaining option will be for an orthopaedic specialist to perform a joint replacement.
This advanced form of knee surgery, which is known as arthroplasty, has been successfully practised for more than half a century, although the earliest attempts to replace a joint date from almost one hundred years earlier. While the practical aspects initially posed difficulties, the concept is a simple one. The damaged ends of the bones are first removed and then replaced with a metal, plastic, or ceramic prosthesis of the precise size and shape. This creates tough new, friction-free articulating surfaces eliminating the pain and eventually restoring full mobility.
Knee replacement surgery may take one of two forms. Where both the head of the femur and that of the tibia show significant damage, the surgeon will perform a total joint replacement, removing the damaged portion of each bone and replacing it with a prosthesis. Often, however, the damage is confined mainly to one of the bones, and thus a partial replacement can be performed. The latter process also means that patients tend to require a shorter recovery time.
Traditionally, arthroplasty requires an incision of between 20 cm and 25 cm to fully expose the joint although some surgeons offer a less invasive option via an incision of roughly half that length. A specialist in arthroscopic knee surgery, however, can give suitable patients the option of a minimally invasive keyhole procedure that will produce minimal scarring.