In our first issue of “Clinical Commentary” on rehabilitation, we introduced the findings of the New Zealand physiotherapist, Robin McKenzie. Among the factors predisposing to back pain is the prolonged sitting postures in normal daily activities, as well as the need to do most activities in front of the body in a forward flexed position. This results in a progressive loss in spinal extension (backward bending) mobility, an important factor that precipitate bouts of back pain.
Back pain is usually benign and “mechanical” in origin. That is, physical stresses of postures and movement (sudden or sustained) often trigger the pain. The client might lament: “I have lifted that box for five years and never had back pain. Why now?” An answer may use the analogy of “the straw that broke the camel’s back”. Likely, it is not the intensity of the load but rather trivial activities can set off an episode – the final “straw” as it were. In fact most episodes of back pain have no identifiable cause. With this in mind, the physical examination and subsequent advice should apply both sustained and repeated spinal movement to determine both aggravating and alleviating mechanical stresses. This is the essence of the McKenzie approach to spinal treatment. By way of advice, let us look at a specific example of low level lifting.
Lifting is the most frequent restriction in the back injured client. Prolonged and repeated forward bending is associated with lifting. This posture with loss of the normal lumbar lordosis results in greater pressures in the disc. According to Nachemson, such pressures can be up to 500% of normal. In the untrained these pressures can trigger an episode of back pain. Appropriate advice includes training to lift with the lumbar lordosis maintained as much as possible while using the legs to actually power the lift. Competitive weight lifters use this technique to lift hundreds of pounds quite safely. Though this is an extreme example, the principle of maintaining lordosis and using the legs is always appropriate in any lifting situation. In keeping with the McKenzie approach, it is advisable to sporadically interrupt sustained lifting by performing a few backward extensions to alleviate some of the spinal stress.
Hercules Grant PhD (Rehabilitation Science)
Feedback and comments to – email@example.com