Lumbar spinal moments in chronic back pain patients during supported lifting: a dynamic analysis.
OBJECTIVE
The main objective of this study was to test the hypothesis that peak L4/L5 moments (torque) placed on the lumbar spine by chronic back pain subjects are reduced using pain-reducing postural adaptations. A secondary objective was to determine the relation between lumbar moments while lifting and self-reported ratings of lower back pain.


METHODS
Cohort using seven men with a history of chronic lower back pain. An inverse dynamic model was used to calculate L4/L5 forces and moments while performing five trials each of two lifting styles. Subjective ratings of lumbar back pain were taken before and after the lifts.


RESULTS
Significant (p < .001) differences were found between lifting postures on peak L4/L5 net reaction moments. Two distinct lifting profiles emerged characterized by the amount of lumbar spinal extensor musculature involved. Significant (p < .05) increases in pain were found after a bowed-back lifting style.


CONCLUSIONS
Peak L4/L5 net reaction moments were less (spine extensor loading) for a lifting posture that produced lower levels of self-reported lower back pain. The dynamic model proved reliable and useful for future study of the pathomechanics of lower back pain.
Wilson
D J
DJ
Department of Physical Medicine and Rehabilitation, Rusk Rehabilitation Center, University of Missouri-Columbia 65212, USA.
Hickey
K M
KM
Gorham
J L
JL
Childers
M K
MK
D000222:Adaptation, Physiological; D000886:Anthropometry; D001416:Back Pain / Q000209:etiology / Q000503:physiopathology*; D002908:Chronic Disease; D006801:Humans; D017770:Lifting / Q000009:adverse effects; D008159:Lumbar Vertebrae / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009068:Movement / Q000502:physiology*; D010147:Pain Measurement; D011187:Posture / Q000502:physiology*; D016059:Range of Motion, Articular; D012399:Rotation; D019415:Torque