5. Importance of the sagittal plane The four curves in the sagittal plane endure 16 (4x4) times more resistance to load than possible in a straight spine.
16. This sketch shows that resistance to loads depends on muscle strength. Muscle tone of the same muscle groups insure balance. Loss of muscle mass in aging places the balance system at risk of failure.
17. The load sharing of the posterior muscles from the spine to pelvis and femoral bone carry the lion’s share.
23. The Sacrum Inclination Bernhardt M Bridwell KH. Segmental analysis of the sagittal plane alignment of the mormal thoracic and lumbar spines and thoraco lumbar junction. Spine 1989;14:717
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25. End of growth Disc degeneration begins around age 35 Facet degeneration begins around age 50 Unstable spine Stable spine ankylosis stenosis spondylo deformity Most often all together Progressive Degenerative Process
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27. Age Related Changes 21-40y Group 41-60y Group >60y Group Pelvic Parameters: Sacral Slope decrease Pelvic Tilt increase Spinal Parameters: Global Inclination tilt forward GL Parameters: GL - Heels doesn’t change Pelvis move backward Kyphosis increase * Lordosis decrease Age
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31. The Degenerative Process 75 year old female Can be invalidating and painful With signs of radiological deformity
