What is the most common reason for having a total knee replacement surgery?
The most common reason for a total knee replacement surgery is degenerative joint disease (arthritis). In simple terms arthritis is wear and tear inside the joint that causes pain, stiffness, deformity and instability. It affects people of all ethnic groups in all geographic locations and occurs as a person becomes older. As the degeneration in the joint advances, the pain in the joint keeps on increasing from an intermittent aching while walking to a constant pain that keeps a person awake at night. The patient has a grating and grinding sensation in the joint with increasing stiffness and joint deformity. This leads to a stage when a person is unable to perform simple activities of daily living like going out shopping, climbing stairs, squatting on the floor, dressing and undressing oneself, and this virtually brings life to a standstill. Increasing deformity sometimes causes a leg length discrepancy and may lead to frequent falls and injuries.
What is knee replacement surgery?
The ends of the bones in the knee have near frictionless surfaces which act as shock absorbers. This protective layer gets damaged as the years go by which causes the two bone surfaces to rub together and cause pain. Knee replacement surgery removes and resurfaces this using metal and plastic. The metal is usually very highly polished chromium and cobalt alloy with negligible coefficient of friction and the plastic is a highly cross linked ultra high molecular weight polyethylene which acts as the shock absorbing cartilage .
Is knee replacement the only answer to degenerative joint disease?
No, knee replacement is the last resort in the management of this disease. The younger patients are advised to modify their activities by avoiding sitting and squatting on the floor. The obese patients are advised to follow a strict diet and lose weight. Patients are advised to undergo physiotherapy simultaneously. The physiotherapists apply heat and cold to the joint, prescribe walking aids, knee braces, shoe alterations, and concentrate on increasing movement and muscle strength. Some of the common physiotherapy modalities are wax bath, interferential therapy, short wave diathermy, ultrasound therapy, laser therapy and simple moist heat and ice packs.
Intra-articular injections of steroids and hyaluronic acid, which acts as a joint lubricant, are also tried before embarking on surgery. When we come to the surgical option knee replacement is again last on the list. If the patient has mechanical dysfunction like locking of the joint, an arthroscopic surgery which is a keyhole surgery performed using a telescope. This smoothens the degenerated shock absorbers in the joint and washes out all the muck and debris in the joint. This is just like taking an old car to the service station and sprucing it up so that it runs better for sometime. Younger patients who are in the range of forty to fifty years with degenerative arthritis affectingone side of the joint, causing bending deformity can benefit from an osteotomy which entails removing a wedge of bone close to the joint and this corrects the deformity, makes walking better and decreases pain. This is used to buy time before a knee replacement is done. The ideal indication for a knee replacement is a fit and healthy patient sixty years and above in whom all conservative treatment modalities have failed.
What are the complications in knee replacement surgery?
Knee replacement surgeries do have complications like any other surgery. It is akin to risks involved in simple activities like crossing a busy street in Bangalore!! All surgeons anticipate complication before hand and take remedial measures and prevent it from happening. Wound healing can be a problem and therefore patients with diabetes are admitted and their sugar levels are controlled before surgery. Patients are advised to stop smoking and improve their lung functions by deep breathing exercises and simple activities like blowing a balloon. If the patient has dental infection or a urinary tract infection, then these conditions are treated before embarking on a knee replacement surgery. Obese patients are requested to lose weight and if there is a suspicion of active infection in the joint, then a knee replacement surgery is completely contraindicated. Before every knee replacement surgery every patient undergoes a very thorough physical and medical examination and investigation. Prophylactic antibiotics are administered to decrease the rate of infection. Blood thinners are given to prevent deep venous thrombosis. Thromboembolic stockings and pneumatic foot and calf pumps are used to encourage circulation and prevent deep venous thrombosis. When knee replacement surgery was first introduced most patients were bedridden for weeks but today they are made to walk on the same day of surgery. This prevents many complications. The operation theatres have become very sophisticated with ultra clean air systems, disposable impervious drapes and surgical space suits which further bring down the chance of infection.
What is the recovery pattern in a knee replacement surgery?
In the bygone days knee replacement patients would use a walker or crutches for a period of six to eight weeks. In recent years patients regain their mobility and function much faster. Most of my patients undergo a minimally invasive surgery through a special sub vastus approach where no muscle is cut. As the muscle is totally preserved, it starts functioning faster and most of my patients walk without support by the end of the second week and are able to climb stairs as well.
If both knees are equally arthritic then should both knee surgeries be done together or one at a time?
Most elderly patients have both knee joints affected equally. The most common dilemma that patients face is the sequence of surgical correction. Should both knees be replaced at the same time or at intervals of three days? Seven days? Or even a month? After weighing all the pros and cons in medical literature, I prefer doing both knees together in the same sitting if there are no red flags. The most important red flags are not diabetes or blood pressure but cardiac complications. A patient with cardiac complications is not a candidate for simultaneous joint replacement surgery. In such cases the second knee should be operated after six weeks by which time the operated knee is well on the road to recovery. Here I will mention that I have replaced both hip joints and also both knee joints of a patient at a single sitting. That's four major joints under one anesthetic and today to the best of my knowledge, has not been performed by any surgeon in the world. It has been more than two years since the time of surgery and the patient is continuing to do well.
Which brand or companies knee joint should I opt for?
These days tremendous market forces are at work trying to catch a patients eye. Unfortunately many people rely heavily on the internet and are sometimes misguided by the overwhelming amount of information available. In my opinion you should trust your doctor and let him decide which joint is suited to your personal need. My thoughts on this matter were echoed two years ago in the annual orthopeadics surgeons meet in San Francisco. A young orthopaedic surgeon asked this very same question to a panel of top notch world renowned surgeons. The panel felt that there was no particular joint that stood above the rest. The joint that the surgeon has been trained to operate with over the years and which gives best results in his hands is the one he should perform with the best outcome for his patient.