Three-dimensional kinematics and trunk muscle myoelectric activity in the elderly spine - a database compared to young people.
OBJECTIVE
To establish a database of lumbar spine kinematics and muscle activation profiles for a healthy elderly population.


METHODS
Spine motion parameters and muscle activation profiles of the elderly were identified and quantified in part by comparison with an existing database of younger people.


BACKGROUND
Databases are often used as a benchmark to establish what is "normal", or for developing appropriate exercise programs or diagnostic methodologies.


METHODS
Twelve people (average age 69 yr) performed full range of motion movements about the flexion, lateral bending and axial twist axes of the lumbar spine. Fourteen torso muscles (7 per side) were monitored with electromyographic electrodes and the signals normalized to maximum voluntary efforts.


RESULTS
The elderly were slower moving, and had a reduced range of motion in full flexion and lateral bend but not in axial twist. Furthermore there was more coupled motion evident in the twisting efforts of the elderly. Abdominal muscles appeared to become more active, earlier in the lateral bending movement.


CONCLUSIONS
Loss of motion is normal with age together with subtle changes in the way the spine moves and groups of muscles are recruited around the torso.


CONCLUSIONS
Quantification of "normal" changes associated with aging will enable clinicians and scientists to distinguish normal changes from pathology.
McGill
S M
SM
Occupational Biomechanics Laboratory, Faculty of Applied Health Sciences, Department of Kinesiology, University of Waterloo, Waterloo, Ont., Canada. mcgill@healthy.uwaterloo.ca
Yingling
V R
VR
Peach
J P
JP
D000368:Aged; D000375:Aging / Q000502:physiology*; D004576:Electromyography; D006801:Humans; D008159:Lumbar Vertebrae / Q000502:physiology*; D009068:Movement / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D016059:Range of Motion, Articular; D012016:Reference Values