As discussed in my last column, gravity is the shaping force of how we hold ourselves and learn to move without falling. Everyone with pain is unstable somewhere. If you are having pain, you have lost control of the joint and its proper movement pattern. This in turn, causes compensation and you become too stable somewhere else to make up the difference. In order for you to move and function without compensation, you need to be stable.
The 3 components of stability are mechanical, neurologic and strength, hence 3 ways for you to become unstable.
Mechanical instability is when tissues have become overstretched so they can no longer hold things in place. In this scenario, the ligaments and muscles around a joint stop providing the proper support. I see this a lot with people having knee pain where the hamstrings or hip capsules have been over stretched repeatedly making them too long. (If you can put your hands flat on the floor your hamstrings are too long). The hamstrings feel tight because they are being pulled taught by the resulting compensation. This unbalances the forces on the hip creating instability. This places greater demand on the knee as it tries to stabilize the hip from the ground up. If mechanical control is lost at the hip, you will rotate through the knee, and not at the hip, causing knee pain and susceptibility of injury at the hip and the knee.
Neurologic instability is when the postural control pattern is altered from a loss of sensory input. The loss is usually because a person has become patterned and only exists in his or her pattern and hence only receives feedback from the pattern. In this scenario, the brain stops receiving sensory input that allows normal reciprocal movement. When there are gaps in the sensory information, the brain will turn on a global extension response to lock you up trying to preserve stability. I see this a lot with people having back or neck pain. The person lacks sensory input from key reference centers, such as the arches of the feet, so the brain turns on the low back muscles putting the spine in extension to stabilize walking. This places increased demand on the spine and disc leading to pain and injury.
Lastly, strength instability is when there is an imbalance of muscular strength around a joint to keep it stable. I see this a lot with people having joint pain. The muscles around a joint act like a revolving door rotating about its axis. If muscle strength is not equal around the joint, the axis of rotation will be lost causing compensation and