Abstract
Purpose:
To produce objective evidence that lifting is more comfortable in lumbar flexion than lumbar extension.
Traditionally, lifting is taught in lumbar extension (“straight back”) but in our experience is more comfortable and stronger in flexion with backward lumbar tilt.
Method and results:
58 subjects performed maximal comfortable static lifts:
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1.
‘Natural’ lifting position - hip flexion, knee extension, lumbar extension
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2.
Traditionally taught position - hip flexion, knee flexion, lumbar extension
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3.
Backward pelvic tilt - hip flexion, knee flexion, lumbar flexion
The order of these lifting methods varied to allow for variation due to fatigue/recruitment. All lifts were measured with a computerised dynamometer.
The mean force for natural lifting was 13.4 kgs, for traditionally taught lifting 15.1 kgs and for backward pelvic tilt lifting 22.2 kgs
This represented a 13% greater load for traditionally taught lift compared with natural lift, 66% greater for backward pelvic tilt compared with natural lift and 48% greater for backward pelvic tilt compared with traditionally taught lift.
Conclusion:
Contrary to accepted teaching and intra-discal pressure studies, this study confirms the observation that lifting strength is greater when the lumbar spine is in flexion. Thus, patients can avoid provoking their back pain when lifting by flexing the lumbar spine.
A possible explanation is reduced facet joint compression in lumbar flexion and load sharing with the lumbar fascia and ligaments.
