Let's say you have knee pain and you undergo an X-ray or magnetic resonance imaging (MRI), which shows arthritis, or worn-away cartilage so your bones are rubbing together or a tear in the meniscus (the cushion-like pad within the knee joint). Your doctor prescribes some medication, but when that doesn't work, he suggests surgery, even joint replacement. When you discover that you still have the same or even greater pain than before, the doctor is mystified and can only offer more drugs to manage your pain.
If this sounds familiar, you're not alone. Of the approximately one billion people worldwide suffering from chronic pain, the vast majority follow the same process and end up in the same place. Yet, in almost all cases, the cause of pain is unrelated to the structural variations found on X-rays and MRIs. Herniated discs, stenosis, pinched nerves, meniscal tears and arthritis are present in abundance without ever eliciting pain. The giant pain phenomenon we see today is based on this one false premise: that the structural variations identified on diagnostic tests are the cause of pain.
Here are five reasons why these tests are almost always wrong about knee pain.
1) MRI and X-rays rarely identify the cause of pain
The idea that the structural variations found on these tests are the cause of pain has no logical basis in fact. These changes are progressive in nature and take years to develop. If these variations were the source of pain, it should follow that those without pain should be free of them. But that's clearly not the case. One study from Boston University looked at the MRIs of 991 people, aged 50 to 90 and ambulatory, and found that, of those with knee pain, 63 per cent had meniscal tears while, of those without knee pain, 60 per cent had the same sort of tears.1
Likewise, a radiographic study from Keele University in Staffordshire of adults with knee osteoarthritis concluded that X-rays are an "imprecise guide to the likelihood that knee pain or disability will be present".2
2) Range of motion at the joint is the best determinant of joint function
If you've had an X-ray showing very little cartilage in your knee joint, the doctor may convince you to get it replaced because the bone rubbing on bone is what's causing your pain. But the truth is, just the tiniest amount of joint space allows the joint to function properly without pain, but such a space can't be identified on X-rays, which lack magnification. If the knee is truly operating bone on bone, there will be a major loss in range of motion, as bone hitting another bone stops the motion from going further. After more than two decades of treating thousands of people who were told their knees were rubbing bone on bone, I can count on one hand those in whom it was causing pain.
3) Joint position is based entirely on the pull of the muscles surrounding them
The muscles that attach to the joint (top image, page 41) determine the location of the joint surfaces. For instance, the kneecap is positioned primarily by the force applied to it by the quadriceps (front thigh muscles). If the quads become too strong in relation to the hamstrings (posterior thigh muscles), the hamstrings will shorten and pull excessively on the kneecap, causing increased compression and pain around the kneecap.
Strained quads can cause the opposite effect, with the reduced force allowing the kneecap to float about too freely and perhaps press sideways on the outer bands of connective tissue (retinaculum) of the joint, causing pain around the kneecap.
If this happens, try stretching your quads by bending the affected leg at the knee and pulling the foot in toward your buttocks. By stretching shortened quads in this way, it should decrease the force on the kneecap and limit the compression, which should decrease the pain. If this is so, it's likely that this muscle imbalance is the cause of your pain.
4) The pain is usually not in the same place as the structural abnormality
One of the most outrageous claims made is that arthritis or a meniscal tear is the cause of pain around the kneecap. The bottom image on the right shows that the knee comprises two joints: one between the thigh and calf bones; and one between the kneecap and thigh bone. The arthritic changes depicted are between the upper and lower leg bones. If pain were due to a meniscal tear, it would be felt at the side of the joint along the 'joint line', which has no connection with the kneecap-thigh bone joint, making any supposed association between arthritic changes or meniscal tears and kneecap pain simply false.
5) If heat reduces your pain, the cause can't be structural
While most of my patients have been told the cause of their knee pain is structural—a herniated disc, stenosis or arthritis—they report that a hot shower or hot pack on the knee reduces the pain substantially, which proves that the cause of the pain is muscular.
Heat doesn't ease arthritis or a herniated disc, but it does make muscles more flexible, and such lengthened muscle fibres disperse the pain receptors along the muscle. Once the heat is removed, the muscle becomes short again, causing a concentration of pain receptors and feelings of pain again. This is why pain is more intense at night and first thing in the morning.
In 95 per cent of my patients, the cause of knee pain is muscular, and appropriate targeted and progressive resistance exercises can resolve the cause and stop the pain.
The three most common muscular causes of knee pain
An imbalance between quadriceps and hamstrings
The quads tend to be stronger than the hamstrings, causing the quads to shorten and, as they attach to the kneecap via a tendon, this pulls the kneecaps upwards and, in turn, causing excessive compression at the knee joint. As the knee is bent and straightened, the increased compression causes irritation and pain around the kneecap.
Solution: Stretching the quads and strengthening the hamstrings and gluteus maximus (buttock) muscles will reverse the imbalance, placing the proper level of tension on the kneecap.
When the quads are strained, there's less of an upward pull on the kneecap through the quad tendon, so allowing the kneecap to float more than it should, making it susceptible to dislocation. As the quads are positioned slightly on the outer side of the kneecap, the dislocation is often towards the outer side of the knee joint, causing irritation
Solution: Stretching the hamstrings and calf muscles while strengthening the quads and anterior tibialis (the muscle at the front and outer side of the shin) will bring the appropriate tension to the kneecap, allowing it to sit in its proper position again.
A strained gluteus medius muscle
Straining of this hip muscle can cause the tensor fasciae latae muscle of the thigh—connected to the outside of the knee joint by a connective tissue band called the iliotibial band (ITB)—to compensate by helping the gluteus medius pelvic muscle provide balance and stability when standing. If the tensor fasciae latae become strained in the process, the ITB will become shortened and, as the ITB is attached to the outer side of the kneecap, it will pull it towards the outside of the knee joint, again causing irritation and pain.
Solution: To resolve this common cause of knee pain, stretching the ITB and strengthening the gluteus medius, hamstrings and gluteus maximus will help maximize stability and balance, so preventing the tensor fasciae latae and ITB from shortening and pulling the kneecap laterally.