Minimally Invasive Surgery (MIS)

MIS Joint Replacement offers important advantages, requiring smaller incisions and potentially causing less trauma, shorter hospital stay, faster recovery and less scarring than traditional techniques.

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Partial Knee Resurfacing

Partial knee resurfacing (PKR) is a surgical procedure for relieving arthritis in one compartment of the knee. With PKR, only the damaged surface of the knee joint is replaced, helping to minimize trauma to healthy bone and tissue.

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Rotator Cuff Repair

A rotator cuff tear is a common cause of pain and disability among adults. A torn rotator cuff will weaken your shoulder. This means that many daily activities, like combing your hair or getting dressed, may become painful and difficult to do.

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Total Knee Replacement

Arthritis of the knee can result in pain that interferes with your everyday life, making even simple activities difficult. If nonsurgical treatment methods fail to relieve your pain, knee replacement surgery may be an option. This surgery is a safe and effective way to relieve pain and get you back to your normal activities.

Anatomy of the Knee

In order to understand how total knee replacement works, it is helpful to know how the knee functions. The knee is the largest joint in the body. The lower end of the femur (thighbone) meets the upper end of the tibia (shinbone) to form the joint. The patella, or kneecap, rests in front to help protect the joint. Articular cartilage is a hardened, smooth substance that covers the ends of the bones.

C-shaped flexible wedges of cartilage (menisci) are located inside the knee joint, between the thighbone and shinbone. They are shock absorbers that distribute weight evenly across the knee joint. Ligaments hold the knee together, providing stability for the joint. A thin membrane of synovium, lines the inside of the joint, producing a lubricant for the knee to prevent friction.

Candidates for Knee Replacement

Arthritis is a common cause of pain and stiffness in the knee. There are three main types of arthritis: Osteoarthritis (wear and tear), Inflammatory (rheumatoid arthritis), and Post-traumatic arthritis.

Osteoarthritis occurs in those over the age of 50, but can occur in younger people as well. With osteoarthritis, the cartilage lining the joint wears away over time, eventually resulting in the bones rubbing together. Rheumatoid arthritis is an autoimmune or inflammatory arthritis that causes the synovial membrane to become inflamed and thickened. This can damage the cartilage in the knee, resulting in cartilage loss. Post-traumatic arthritis can occur following injuries to the knee. Fractures to the knee can damage the articular and fibrous cartilage, limiting function of the knee.

These conditions are often first treated with nonsurgical methods, such as physical therapy, anti-inflammatory medications, bracing and assistive devices (canes/walkers). However, if these methods do not improve your condition and quality of life, your doctor may consider knee replacement surgery.

The Procedure

It is common prior to surgery to have femoral and sciatic nerve blocks to manage post-operative pain and to avoid the sequela of nausea and vomiting. The Anesthesiologist will then offer additional methods of pain control such as traditional endotracheal intubation, spinal blocks or epidurals.

During the procedure, Dr. McLennan will remove the damaged cartilage and bone, and resurface these areas with implants. The lower end of the femur is replaced with a chrome-cobalt femoral component that curves around the end of the bone. The upper end of the tibia is replaced with a titanium tray that allows placement of a high density polyethylene insert. The tray has a metal platform on the bottom that assists in holding it to the bone. The tray may be press fitted on to the end of the femur or cemented to it. The undersurface of the patella (or knee cap) may have minimal wear, not necessitating resurfacing (replacement). Your new knee allows immediate structural stability, that encourages immediate ambulation.


Following surgery, Dr. McLennan will prescribe medications to help with any discomfort. Initially your pain will be managed by blocks, epidurals and conventional IV and oral medications. You will use a continuous passive motion (CPM) exercise machine to assist and regain your motion. In general, the machine is set at 0-45 degrees of flexion, increasing the flexion 5 degrees twice per day and using it 1 hour in the AM and PM. This machine can help to decrease swelling and improve blood circulation in the leg.. You may even walk on the day of surgery, pending pain control and balance. To go home, you must be able to get out of bed, go to the bathroom and be able to be left without out help for 4 hours.

It is important that you take precautions to avoid falls during the first few weeks after your surgery, as falling can result in complications and the need for further surgery. Most patients are able to return to their normal activities within three to six weeks after surgery.

Total Knee Replacement in Palm Desert, CA

Dr. Jon G. McLennan MD has over 30 years of experience in Orthopaedic Surgery. He uses the most up-to-date techniques, and believes that a close doctor-patient relationship is important to achieve the best outcome. For more information about total knee replacement, or to schedule an appointment with Dr. McLennan, please contact the office at (760) 771-4900.