Osteoarthritis (OA), commonly referred to as arthritis, is a common ailment that can affect 1 out of every 2 people by the age of 85. One of the most common areas to get arthritis is the knee joint. This can be an incredibly painful and lifestyle-altering malady. Arthritis poses a Catch-22 for those afflicted with it: Arthritis makes it painful to move the knee joint, but movement is helpful in reducing pain and loss of mobility. As the saying goes: “motion is lotion”.
What is Arthritis?
Arthritis of the knee is the degeneration of the articular cartilage that allows the femur (thigh bone) to weight bear on the tibia (shin bone). Without this cartilage, the bone of the femur is contacting the bone of the tibia directly and can be very painful. There are four stages of the arthritic process as it ranging from doubtful/healthy to severe.
There are many different treatments available for treating the symptoms of arthritis. Knee replacement surgery is currently the most effective fix for these issues. Most knee replacement surgeries occur between the ages of 50 and 80 with the average age being 70 at the time of replacement. The surgeon typically wants to wait as long as possible before doing the surgery as the knee replacement will not last forever. Although, one study found that 96% of knee replacements were still functioning 20 years after the surgery, you still want to avoid the chances of requiring it to be redone in your later years of life (80 years and up).
For the arthritic patient in their 50s this does not leave a very cheery outlook. Either they wait for surgery for 10 or more years while going through life in pain and significantly modifying their activity level, or they go in for surgery early and risk having to go through surgery again at age 85, for example, when healing times are longer and rehab is more difficult.
So how can we delay the requirement of knee replacement surgery – or what if it isn’t an option, as in the case of someone who has other complications that prevent them from being able to have surgery. In other words:
What are the alternatives to surgery for arthritis of the knee?
The patient can be prescribed drugs such as NSAIDs (non steroidal anti-inflammatory drugs) and this can help them deal with the pain, although it won’t affect the condition, potentially allowing it to worsen. The patient can receive an injection of a corticosteroid, which provides temporary relief. However, there is a limit to how many injections a doctor will recommend and the relief only lasts for up to 3 months. Physiotherapy can help strengthen the muscle groups around the knee but of course will not remove the underlying arthritis.
The fundamental problems surrounding the arthritic knee is the loss of articular cartilage and the shape change of the knee that can occur with that. The leg may go into a bow-legged shape (also known as varus) or a knock-kneed shape (also known as valgus). In the picture to the right the knee has gone into a bow-legged shape. This has been caused by a loss of articular cartilage in the medial compartment (inside of the knee) which has allowed the joint space on the inside to decrease. This further increases the amount of load on the inside of the knee which increases the amount of pain due to the bone on bone forces.
Unlike the other treatments (excluding knee replacement surgery), knee bracing aims to address this shape change and lessen the amount of loading occurring on the affected side of the knee. The knee brace pushes the knee in such a way that it increases the load on the healthy side and therefore decreases the load on the arthritic side. In the force diagram shown below forces are applied on the medial (inside) surface above (F1) and below (F3) the knee and on the lateral surface at the height of the knee joint (F2). This creates a rotation (M1) which offloads the medial compartment.
Offloading knee braces can create an immediate decrease in pain as well as a long term benefit as the stress is decreased from a chronic standpoint. They can therefore effectively be used a stop gap orthopedic strategy to allow you to live your life while waiting for the appropriate time for your knee replacement surgery. Please contact us to find out if you are a candidate for offloading knee bracing. Please Click Here for more information on our custom bracing process as well as unique funding sources that we at Guelph Orthotics have access to to help minimize or eliminate the cost of the brace.
Murphy L, Schwartz TA, Helmick CG, Renner JB, Tudor G, et al. Lifetime risk of symptomatic knee osteoarthritis. Arthritis Rheum 2008;59(9):1207–1213 doi: 10.1002/art.24021. PubMed PMID: 18759314. abstract