Callaghan J. and McGill, SM, Clinical Biomechanics 2001; 16:28-37

Flexion extension forces with disc compression loads.  Compression of spine and utilizing seated low back machines can cause shearing of annular fibers.  Accumulation of forces will induce disc herniations. 

 

 

 

Liebenson, C., Rehabilitation of the Spine, p. 96

Callaghan and McGill have been able to consistently produce disc herniations by mimicking spine motion and load patterns seen in workers and in replicating the motion and loads of seated lumbar extension exercise machines.

 

 

 

 

 

Panjabi and Ito, Spine 2004; 29(9):979-987

 

Soft tissue injury threshold; partial tears of soft tissue include annular fibers, ligaments, and avascular cartilage; poor blood supply may not allow complete healing of tissue, therefore altering spinal kinetics thus leading to accelerated degenerative changes and clinical instability

 

 

 

 

 

 Fryer, Morris, Gibbons, Journal of Manipulative and Physiological Therapeutics 2004, pgs 348-57

 

Mechanical stimulation of deep spinal structures produce reflex activation, not inhibition of multifidus.

 

Contraction of multifidus is delayed or absent in patients with low back pain.

 

 

 

 

 

Carolyn Richardson PhD, Therapeutic Exercise for Spinal Segmental Stabilization in Lower Back Pain, Churchill Livingstone 1999

 

Contraction of multifidus is delayed or absent in patients with low back pain.

 

  Multifidus:  largest muscle in lumbosacaral junction controlling sliding movements of facets and distraction of stresses and loads on vertebral joints.

 

Primary function of multificus is to protect vertebral joints.

 

 

 

 

J. Cox, Low Back Pain Biomechanics of Lumbar Spine, pg. 89

 

Flexed postures increase fluid exchange to the disc more than erect postures.

 

 

 

 

 

Mooney J. Musculosk, Med 95 Oct

 

In soft tissue injuries, progressive physical activity activates extra cellular and neurovascular fluid, thus improving fluid exchange and promotion of healing.

 

 

 

 

 

Mooney, Backstrong.com 2001

 

Discs can not repair themselves very well, they are avascular.  Activity "pump" exchange of fluid in the disc, best by repeated flexion, extension, flexion.  Hydrates the disc.

 

 

 

 

Danneels, et al., British Journal of Sports Medicine 2001

 

Strengthening multifidus reduces back pain.  Training with maximal and sub maximal effort may reverse selective atrophy in multifidus.

 

 

 

 

Parkkola, R., J Spinal Disorder 1992, 5(1): 86-92

 

Muscle fat increases with age, causes muscle degeneration in lumbar area, correlation with disc degeneration.  Fatty infiltration of multifidus on MRI.

 

 

 

 

Ebenbichler Med. Sci Sports Exercise 2001; 33(11): 1889-98

 

Any injury to the multifidus will affect lumbar segmental stability.