Patella Tracking Dysfunction - Discovering the truth
by Michael Young, NCTMB
Many people, from athletes to gymnasts to housewives to construction workers, suffer from a patella-tracking problem. Runners are especially prone to this disorder. Some runners are diagnosed with runner's knee. This problem presents itself as a localized pain around and under the kneecap. Many times it is accompanied by popping, clicking or grinding noises as the patient runs or walks.
What are the symptoms of Patella Tracking Dysfunction?
- Pain in front of the knee.
- Crunching in the knee and under the knee.
- Swelling in the knee.
Symptoms will increase with many daily activities such as stair climbing, cycling, walking, aerobic activities and sitting for prolonged periods of time.
What is Patella Tracking Dysfunction?
The patella glides in the groove of the femur and "tracks" with the bone as a person flexes or extends the knee joint. The patella is a small bone in the front of the knee that is embedded in the patella tendon of the quadricep muscles. Since the patella floats and should track down the middle of the femoral groove, proper tracking is essential to remain pain free. If some force pulls the patella out of this track, the patient will experience pain. When this force continues to pull the patella out of its track for a long period of time, the patient will develop Chondromalacia Patella. This condition is caused by a break down of the cartilage under the patella and is very common in athletes who do a lot of running and jumping. If left untreated little fragments of the cartilage will begin to break off. Chondromalacia will eventually result in a complete loss of the cartilage lining beneath the patella. In severe cases surgery is necessary to remove the fragments of cartilage.
What is this force that pulls the patella out if its track? One must look at and understand the anatomy of the leg and knee to discover the proper treatment of this dysfunction. There are four quadricep muscles. They are:
- Rectus Femoris
- Vastus Lateralis
- Vastus Intermedias
- Vastus Medialis
As a group, the quadricep muscles are the strongest muscles in the body. All four muscles connect to the patella tendon. This tendon goes over the top of the patella. When one of these muscles becomes too tight, it will pull the patella out of its track. Many health care professionals view this as an imbalance in the muscles. In other words, they consider one muscle to be strong and another muscle to be weak. The rectus femoris, vastus lateralis and vastus intermedius pull laterally on the patella. Most often this is the reason the patella is pulled out of its track. The only quadricep muscle that has a medial pull on the knee is the vastus mediallis. It is no surprise that almost all patella-tracking problems occur laterally rather than medially. This is due to the fact that there are three muscles pulling against one.
Most health care professionals are trained to believe that this imbalance means that the vastus medialis is weak and needs to be strengthened in order to correct the problem. Many times when the vastus medialis is strengthened, the patella goes back into its track and the pain disappears. This seems simple enough and tends to make sense. However, the problem with this is that the patient then determines that strength work will keep him out of pain. We all learn that strength work will shorten a muscle. If the patient continues with the strength work on his quads, the four quad muscles will all shorten causing the patella to track high. This results from the tight muscles pulling the patella in that direction. Similarly the three lateral quads can pull the patella out of its track, as mentioned above. One should not assume that a short, tight rectus femoris muscle means that the vastus medialis muscle is weak and requires strengthening.
It has been my experience that patella-tracking problems are caused when the quadricep muscles are overworked. When a person overworks (or over strengthens) a muscle, the result is a hypertonic muscle. It says in the Whartons' Stretch Book1, "There is a big difference between a strong muscle and a tight one. A tight muscle can be very weak and offer virtually no protection for a joint. Tightness doesn't help--in fact, it hurts." Over-strengthening a muscle will not only make the muscle hypertonic; it will also make the muscle weak. This weakening is due to the fact that a lot of the strength in a muscle comes from the contractile range of the muscle fibers. If the muscle is 75% short, it can only contract 25%. If only makes sense that a short, tight muscle will be weak. Most rehabilitation therapists conduct tests on the short, weak muscles and determine that the muscles need strengthening. The hypertonic muscles pull bones out of alignment, entrap nerves and restrict circulation. They will also pull the patella out of its alignment.
Initial treatment focuses mainly on physical therapy techniques for strengthening the quadriceps to balance the patella tracking. In more severe cases, ice and anti-inflammatory drugs will be used to calm down the inflammation before exercises can be resumed. At times a patella tracking brace or special taping techniques will be used. (These treatment modalities only treat the symptoms, not the cause). The last resort is surgical intervention.
In extreme cases arthroscopic surgery can be helpful in smoothing out the rough surface on the underside of the patella. During this surgery loose fragments of cartilage are also removed. Another surgical procedure for this condition involves making an incision in order to tighten the inner ligaments that help control the tracking. A more recent surgical technique being used for patella instability is the use of a heated probe to shrink the stretched patella ligament or retincullum. This method is currently being utilized for patients with less severe instability of the patella. One surgeon using this technique is Dr. Jeffrey L. Halbrecht at the Institute for Arthoscopy and Sports Medicine in San Francisco, CA.
The Common Sense Solution
I have been able to bring tremendous relief to patients seeking help for patella tracking problems, in as little as one treatment. People often laugh when I say this but keep an open mind when reading on and I will explain further. Most of us know that a short tight muscle needs to be stretched. If we correctly stretch all four quadricep muscles, the tracking problem will disappear. I have found that the rectus femoris is the culprit for most tracking dysfunction. Why, you may ask? The rectus femoris is the only quadricep muscle that attaches above the hip joint. Often we see runners stretching their quads prior to starting their run. Most people stretch by grabbing the ankle and pulling the heel towards the gluteus maximus while bending over (see photo 1). As soon as the person bends over he takes the rectus femoris out of the stretch (see photo 1). This manner of stretching does nothing to stretch the Rectus Femoris but does stretch the other three quadricep muscles. The Rectus Femoris plays a double role. It not only extends the leg at the knee joint; it is also a hip flexor. This muscle does twice the work of the other three quadricep muscles. It is no wonder that it often becomes hypertonic.
When a person overworks any muscle in the body, the result is a short, tight muscle. These muscles do not show up on medical tests, such as MRI's or x-ray's, so they are overlooked as being the culprit for patella tracking problems. If we, as therapists, learn to correctly stretch these hypertonic muscles, the patella will fall right back into its track without drugs or surgical intervention. There are many different types of stretching techniques advocated in our industry. It has been my experience that the Active Isolated Stretching Techniques taught by Aaron Mattes work the best, by far.
Have the patient lay on his side to stretch the quadriceps. Stand behind the patient and start stretching the quads by pushing the clients heel towards his gluteus maximus (see photo 2). When performing the stretch, stretch only hard enough for the patient to feel a good firm stretch. When we stretch too hard, the muscle will tighten up even more. Hold each stretch for only two seconds, then fully release the stretch (see photo 3). Repeat this stretch twenty to thirty times.
To isolate the rectus femoris, the therapist must extend the thigh back in order to place the thigh out of line with the patients body (see photo 4). Once the muscle is isolated, holding the patient's knee back (in extension) while moving the heel towards the gluteus maximus performs the stretch. Note - if the rectus femoris is tight (which will be the case with most patients), the heel will not come close to the patients gluteus maximus because the origin of the muscle is the anterior inferior iliac spine. If the therapist finds this to be the case when performing this stretch, the culprit to the patients tracking problem is a tight rectus femoris muscle. Repeat this stretch twenty to thirty times, stretching only hard enough until the patient feels a good firm stretch. Hold each stretch for two seconds and release each stretch fully.
An important aspect to ensure the patient does not have this problem return is teaching the patient the proper way to stretch at home. The patient should lie down on one side of his body. With his hand he should pull his heel towards his gluteus maximus until he feels a good firm stretch (see photo 5). If the patient can not reach his ankle, he can use a rope or belt to perform this stretch. Once he is in that position, he should hold the stretch for two seconds and then release the stretch fully. Instruct the patient to do twenty to thirty repetitions of this stretch on each side of his body on a daily basis. Ninety-eight percent of the patients who follow this simple advice will remain pain free from the patella tracking dysfunction problem. Persons can avoid developing patella tracking problems by stretching the muscles on a daily basis. This treatment is not magic; it's just common sense.
1 Jim and Phil Wharton "The Whartons' Stretch Book," Three Rivers Press 1996; xxiv Introduction: Myth 7