Thoracic spine rotation

The spine is an engine. The axial pull of the muscles on the thoracic and lumbar spine are transformed by coupled motion into axial torque, which is then applied to the pelvis. The spine is now divided into three segments the lumbar spine, which causes the pelvis to rotate the thoracic spine counter-rotates to dissipate torque and utilizes linked movements of the upper extremities in so doing. The cervical spine de-rotates in the opposite direction to allow the head, eyes and sensory organs to have a stable platform which faces the direction of travel. 

The examiner may find a localized area of thoracic spine, encompassing no more than three contiguous vertebrae, that exhibits severe flattening of the usual kvphotic pattern. This relationship can occur at an area of change of direction of a scoliotic curve, such as a right convexity becoming a left convexity. If rotation in both... 

Rotation is the greatest motion in the larger part of the thoracic spine (Tl-TlO). The amplitude of rotation is markedly decreased in the lower part ofthe region. The articular orientation ofthe thoracic vertebrae allows them to rotate about a point in the center of the vertebral body. The articular orientation of the lower thoracic vertebrae, however, is similar to that of the lumbar vertebrae and permits rotation only about a point near the spinous process. This rotation is greatly resisted by shearing forces in the intervertebral disk. The extent of rotation is further diminished by the resistance afforded by the intact costal cage. 

Figure 39-1 shows the locations of the anterior tender points for the thoracic spine. All anterior tender points are treated with flexion as the major movement in positioning. Fine-tuning of the position will be by side-bending and/or rotation. 

FIG. 39-7 Counterstrain technique for posterior tender point mid-thoracic spine. Tender point is to the right siight rotation is induced to the ieft. 

Thoracic spine forward bending, backward bending, rotation, side-bending. 

Most of the rotation will occur in the thoracic spine because of the fact that the lumbar vertebrae are limited to approximately 5 degrees of rotation in each direction. 

A short leg has numerous effects on the body. Usually, the sacral base lilts toward the side of the short leg. The iliac crest is generally low on the short leg side. Occasionally, the innominate on the shorter side will rotate forward or the opposite side posteriorly as a means of compensating for the leg length discrepancy. The lumbar spine develops a convexity toward the side of the short leg, and once the problem has existed for sufficient time, a compensatory curve will develop in the thoracic spine. The shoulder will be low on one side, depending on whether a secondary thoracic curve is present the scapula will be low on the same side as the shoulder. The cervical angle will be more acute as the head tilts toward the midline to keep the eyes level. 

Coming back to the spine as an integral part of the human body and the involved, mechanical components, first we have passive elements (Fig. 3) the spinal column as the important load transferring element the hip-joint, which transfers the loads to the legs the ligaments, which control and restrict the motion of the spine the rib cage, which especially increases the rotational stiffness in the thoracic area... 

Type I and type II dysfunctions refer only to somatic dysfunctions in the thoracic and lumbar vertebrae because Fryette s principles only apply to these areas. However, in common usage, somatic dysfunctions in the typical cervical spine are often referred to as type II, Motion characteristics of the cervical region dictate that the typical cervical vertebrae side-bend and rotate toward the same side regardless of dysfunction or normal functioning. The distinction is the involvement of a flexion or extension component in the dysfunctional unit. 

Harrison Fryette, in Principles of Osteopathic Technique, discussed specific coupled motion patterns. Of relevance here, when the spine is at rest, normal lateral flexion in one direction will cause the vertebral body to rotate in the opposite direction. (This rule apphes oidy to the thoracic and lumbar regions.) If a group of vertebrae side-bend toward the right, the vertebral bodies will... 

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