One of the most frequent but misunderstood causes of low back pain is failure of the sacroiliac joint to do its job. It is a major weight-bearing joint and transfers all the weight from the torso onto the leg. Every time you step, all of your weight passes through this joint. When the joint fails, it causes pain in the back, in the buttock, into the front of the hip, and down the thigh to the knee. Because of this pattern of pain, it is frequently misdiagnosed as sciatica or sciatic nerve irritation.
Once this joint fails, it can linger as a problem for years. In my opinion there are two reasons for this. The first is that this joint never gets to rest. Every time you get up, stand, or walk, your sacroiliac joint is being stressed. The second reason is that the firing of pain fibers from the sacroiliac joint prevents the activation of the muscles in the hip associated with the joint’s function. This results in a decrease in stability in the joint. Once this cycle of instability starts it can continue indefinitely. People frequently experience this as chronic underlying ache the top of the hip or pain into the groin, thigh and knee. This pain frequently (but not always) is worse getting out of chairs, climbing stairs, and after prolonged walking.
As time goes on and this weakness persists, we develop tension spasms and pain in the spine as the muscles tighten up in an attempt to accommodate for this weak joint. Our pattern of movement changes and we increase the strain on the hip, knee, ankle, foot, and spine. Soon we have lower extremity pain that is a result of compensatory activity. These people come to our office with multiple diagnoses of plantar fasciitis, knee arthritis, hip and knee bursitis, tendinitis, neuropathic pain, etc. Frequently they have been treated for these problems over the year but persist with the pain in these areas. What is not being recognized is they have a single problem called kinetic chain failure because of a dysfunction of the sacroiliac joint. Basically, they have developed a pain syndrome because of a spreading weakness combined with compensation activities of that leg in response to a sacroiliac lesion. Once the sacroiliac lesion is resolved these people are usually able to quickly resolve the multiple problems they have in that extremity.
When treating a dysfunction of the sacroiliac joint I have found there are two things that need to be done. The first is to reduce or resolve the joint lesion. There are many avenues towards doing this, including manipulation, isometrics, stretches etc. While all the techniques can work to resolve the lesion, the technique used is dependent on the specific findings during an exam. Once the joint lesion is reduced, specific stabilization exercises need to be done to stabilize the hips and pelvis. These exercises are dependent on the functional ability of the muscles and should be targeted at the deficits. If the exercises being done are appropriate, changes in stability should quickly be apparent.
Unless both of these issues are addressed, it is likely that there will be chronic pain in the back, hip, knee and thigh with a tendency for that pain to spread up the spine to the low back all the way to the neck. Anyone who has ongoing or recurrent episodes of hip, thigh, back, or knee pain should have their sacroiliac joint and pelvic stability assessed.