This article has some excellent Figures showing various postures and musculature.
When treating myofascial trigger points (TrPs), contributing musculoskeletal, posture, and motion factors must be addressed in order to optimize outcomes.
Etiologies of Chronic Low Back Pain
While herniated disc, spinal stenosis, spondylosis, and facet arthropathy are often considered along with myofascial origins, myofascial trigger points (TrPs) have been shown as coexisting with the other commonly accepted causes.
Injection of active and painful myofascial trigger points from any origin may produce variable decreases in pain and improvements in mobility. Therefore, myofascial trigger point injections (TrPIs) are considered a significant treatment adjunct to low back pain
Chronic postures may promote muscle force imbalances between the antagonistic muscle groups that lead to repetitive stretch trauma of the weaker muscle groups
As an example, shortened hamstring muscles may force secondary overstretching of lumbar extensor muscles during low back flexion
In situations of advanced muscle force imbalances, aggressive lumbar flexion exercises and TrPIs may also further weaken or overpower the posterior supporting ligamentous structures to allow segmental spinal movements which can lead to spondylosis and more pain generating processes.
Most spinal dysfunction is the product of cumulative microtrauma in multiple regional tissues from problems in trunk stabilization, alignment, and movement patterns. Core and spinal stabilization depends on balanced isometric support and movement control primarily provided by trunk musculature.3-5 When low back pain arises, one goal should include evaluation of directions for trunk and spinal alignment, stress, and movements that produce or increase pain.
A common denominator for most spinal related pain is an excessive relative flexibility at specific segments, rather than reduced flexibility from such factors as spasm
Those segments with reduced flexibility promote compensatory motion at the most flexible regions. While vertebral column pathology (disc herniations and bulges, spondylosis, facet arthropathy, and nerve compression) can promote pain independently, addressing trunk musculature issues first, and then those secondary abnormal spinal stresses, may reduce or alleviate the pain completely
The trunk muscles must hold the vertebral column and pelvis in optimal alignment, as well as prevent potentially injurious segmental movement. Therefore, observing body mechanics during various positions and movement may shed light on relative flexibility of various regions, and the impact on spinal stresses which produce pain
An initial observation of spinal mechanics should include lumbar curvature. Decreased lumbar curvature may result in a ‘flat back’, while increased curvature may result in excessive lordosis “sway back.
An anterior tilt of the pelvis increases lordosis, while a posterior tilt reduces the lordosis
Weakened or lengthened abdominal muscles may not adequately support the anterior pelvis, allowing increased tilt, and exaggerated lordosis
Additionally, shortened hip flexors, such as the iliacus, psoas muscles (originate in the posterior pelvis and lumbar vertebrae, rectus femoris, sartorius, tensor fascia latae, and pectineus (originate from anterior pelvis) can enhance forward pelvic rotation to exaggerate lumbar lordosis by essentially pulling the structures forward
Shortened hamstrings, with weakened hip flexors may promote a posterior pelvic tilt, and flattening of the lumbar lordosis
Length or strength differences in groups between sides may promote asymmetry as one side of the pelvis rotates more, leading to additional rotational forces on the spine