Knee Pain: Does It Mean a Knee Replacement?

By Nancy McCarron, Physical Therapist Assistant     –

knee painKnee pain can be as irritating as low back pain as it can hurt when you walk, hurt when you stand, and hurt when you sit. As we put stress on our knees with activity, with inactivity (yes, with inactivity), and with extra weight bearing (those 10 pounds you swore you’d loose after the holidays), they talk to us. But are they saying, “Replace me?”

What is Osteoarthritis of the Knee?
X-rays are the standard diagnostic tool for determining the level of degenerative changes/osteo-arthritis in the knee joint and for assessing joint integrity after a fall. Osteoarthritis is defined as a degenerative change caused by the breakdown of cartilage that protects the ends of bones in a joint; without protective cartilage, the nerve endings in the bone are exposed and cause pain. Even if you have a knee joint with considerable osteoarthritis, you may not need to run to the hospital for a knee replacement. Conservative management, including physical therapy, will often provide pain relief and help you return to an active lifestyle.

Treatment/Behavioral Recommendations
The American Academy of Orthopaedic Surgeons did a systematic review of published studies on treatment of osteoarthritis of the knee. Highlights of the reviewed articles include these five treatment/behavioral recommendations:

  • Weight loss of 5% will reduce symptoms, especially in patients with a body mass index greater than 25.
  • Low-impact aerobic exercise will reduce symptoms and improve lifestyle.
  • Specific quadriceps strengthening will provide joint stability and reduce pain.
  • Intra-articular injections of corticosteroids may be beneficial for short term pain relief but there is “little evidence” to confirm longer term benefits.

Get a Second Opinion
What are your options after diagnostic x-rays which determine you have significant joint degeneration which the physician says is causing your pain and recommends that you have a knee replacement? Before any surgery, it is wise to get a second opinion. Ask another surgeon for an opinion and discuss the type of prosthetic that will be used. Consider if you should first work on weight loss to reduce the stress on the joint because even if you have the surgery, recovery and rehabilitation will be easier. You might wish to try conservative management with physical therapy to see if you can stabilize the knee with muscle strength in order to return to an active lifestyle.

Physical Therapy Benefits Before a Surgery
And, when you are certain that a knee replacement is right for you, schedule an evaluation with a physical therapist at least one month prior to surgery. The therapist can customize an exercise program which will help you strengthen leg muscles and make your rehab after the surgery less painful and, usually, faster.

Determining the Cause of Knee Pain
If the x-rays are negative for significant joint degeneration, what is causing the pain? The knee joint can be influenced by dysfunction other than osteoarthritis and by dysfunction in the low back and in the surrounding joints. Determining the cause of the pain can be illusive without screening from the physician and possibly, more importantly, the physical therapist—a specialist in the science of movement.

The knee, being located between the hip and the foot and governed by nerve roots that start at the lumbar spine, can be in pain but not necessarily arthritic. Let’s start at the low back. Each level of the spine has nerves which exit the central spinal canal through small openings called foramina. Each level of the spine governs the function of different muscles or organs and, also, different sensory areas of the body. These distributions are called dermatomes and they follow a specific and predictable pattern. Especially for people with a history of low back pain, knee pain can be symptom of a disruption of the flow of nerve impulses being sent from the nerve root to the leg muscles causing the muscle to be unable to do its work. This will either cause pain in the muscle or cause a muscular imbalance which changes the mechanics of the knee joint thus making evaluation of the low back a prudent place to start with figuring out what is causing the knee pain.

Next in line is the hip. The hip is a large joint and has over 20 muscles which govern its movement; it carries the weight of the trunk, arms and head and it absorbs the shock of gravity that is transmitted up the leg. The hip is affected by sitting and standing posture and is very susceptible to muscle imbalance and to degenerative changes. Muscle imbalance at the hip affects the knee as well, especially since several hip muscles also move the knee joint into bending and straightening and since the femur is the large bone included in both the hip and the knee joint. Research confirms that strengthening the hip joint is critical in providing stability for knee function and will often help to diminish knee pain.

Below the knee, the foot and ankle are culprits for causing knee pain, especially since the knee and ankle share tibia, the lower bone of the knee joint. If the ankle is weak, it can take the tibia out of line with the femur in the knee joint which causes muscle imbalance at the knee and, eventually, will cause structural damage to the knee joint.

Start Living Without Knee Pain!
Knee pain can be a combination of problems, also. This is where the time you spend with a physical therapist can be especially helpful because we constantly assess your pain, your strength and your movement. At Progressive Physical Therapy, we believe that you deserve a customized approach to solving the cause of your pain and weakness. At our dedicated facility, we use a team approach to patient care and have a reputation for great success. Maybe it is time for you to start living without knee pain!

To learn more or to schedule an appointment, please call Progressive Physical Therapy at 941-743-8700, or visit us online at www.progressivehealthplex.com.

Ref: Journal of American Academy of Orthopaedic Surgeons; AAOS Clinical Practice Guideline Summary: Treatment of Osteoarthritis of the Knee (Non-arthroplasty); September 2009, Vol 17, No.9.