THE RELATIONSHIP BETWEEN POSTURE, PAIN & MUSCLE ACTIVITY IN THE LUMBAR SPINE
7th January 2011
A post by Patrik Pedersen, Kinetic Control Accredited Tutor, Sweden
Low back pain is common, and as we know has many contributing factors one of which is provocative spinal postures. Even though it has been postulated that prolonged sitting or standing is not independently a risk factor for LBP it is known to be an aggravating factor.
What is good/bad posture? A short summary from the Posture Committee of the American Academy of Orthopaedic Surgeons in 1947 states: ”Posture is… the relative arrangement of the parts of the body. Good posture protects the supporting structures….the muscles will function most efficiently…Poor posture….produces increased strain on the supporting structures…” I think that we can agree with this statement even 63 years later. There is a debate in the literature regarding what ”ideal” posture is. Many postures such as flat posture, long lordosis, short lordosis, and slight lumbar lordosis with relaxed thorax have been suggested. What has been shown is that passive postures such as sway standing and slump sitting decreases activation of the stabilising muscles. Many studies on posture do not subclassify the people with low back pain and therefore there is a risk for the so called washout effect, but when patients are subclassified there is significant differences, patients tend to sit closer to their symptomatic posture, patients with an active extension pattern sit more lordotic and patients with a flexion pattern sit more kyphotic. Correcting posture has shown to have a facilitory effect on stabilising muscles. It has also been found that changing alignment can improve symptoms. The Problem with literature on posture is that there is no consensus on natural/ideal posture, many different measuring methods and measuring sites are used and most studies do not subclassify.