Vertebral body, thoracic spine

There exist major differences between the thoracic (Tl-10) and thoracolumbar vertebral bodies (T11-L5), since the rib cage serves as a stabilizer of the thoracic vertebral column. Four factors have to be determined (1) percentage of osteolyses in the vertebral body, (2) presence of involvement of the pedicles, (3) posterior elements, and (4) costovertebral joint involvement at the thoracic spine (Taneichi et al. 1997). 

A vertebral body is at risk of fracture in the thoracic spine if more than 50% of the vertebral body is missing or if more than 25% of osseous destruction of the vertebral body is combined with a destruction of the costovertebral joint (see above Fig 35.14). In the lumbar spine, a vertebral body is at risk of fracture if more than 35% of the body is destroyed or if a more than 20% de-... 

Vertebral body (Fig. 37.9) depending on the vertebral level, the access path is anterior (cervical spine), transpedicular or intercostovertebral (thoracic spine), and transpedicular or posterolateral (lumbar spine). 

To date, the mechanical properties of the metastatic spine and the mechanisms of collapse have not been fuUy elucidated. Moreover, the correlation between vertebral body coUapse and the location and extent of the metastatic tumor is not fully understood. Taneichi et al. (1997) evaluated 100 thoracic and lumbar vertebrae (53 patients) with osteolytic lesions, determined risk factors for vertebral coUapse, and estimated the probability of coUapse under various states of metastatic vertebral involvement. The most important risk factor leading to vertebral coUapse in the thoracic region was involvement of the costovertebral joint. Tumor size within the vertebral body was the second most important risk factor. In-... 

Taneichi H, Kaneda K, Takeda N, Abumi K, Satoh S Risk factors and probability of vertebral body collapse in metastases of the thoracic and lumbar spine. Spine 1997 22 239-45... 

For the treatment of the thoracic and lumbar spine the patient is positioned in a prone position and the skin overlying the vertebral body is cleaned and draped under strict sterile conditions and local anesthetic is administered to the skin and the subcutaneous tissue including the periosteum. The access route depends on the region of the spine that has to be treated. Vertebroplasty can be performed by a unipedicular or bipedicular approach, but most authors think that the unipedicular approach is... 

Fig. 2.10.1a-d. Different approaches to the vertebral bodies a transpedicular approach is preferred in lumbar vertebra (a) while an intercostovertebral approach (b) is preferred in thoracic spine. A posterolateral access (c) route can be used in lumbar vertebral bodies, if the pedicles are destroyed or this access route is complicated by surgical implanted material. In cervical vertebrae an anterolateral approach (d) is chosen - special care has to be taken not to harm the carotid-jugular complex... 

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... 

Although the thoracic spine has characteristic features that distinguish it from the cervical and lumbar spinal regions, it is mainly a transitional zone between the cervical and lumbar regions, as evidenced by the steady increase in height of the vertebral bodies from T1 to T12. Moreover, the inferior articular facets of T12 correspond to those in the lumbar area to allow proper articulation with LI. The different forms of articulation play a considerable role in the amplitude of various physiologic motions in the thoracic spine. 

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. 

Some of the counterstrain tenderpoints correspond to vertebral segment dysfunctions. As in other areas of the body, when counterstrain treatment is used in the thoracic spine, the positions are held for 90 seconds. The patient is returned to a neutral position slowly, without any muscle contraction on his part, and the tender point is reassessed. 

The thoracic spine is subject to many conditions that affect the cervical and lumbar spine including somatic dysfunction, herniation of an intervertebral disk, arthritis, and other bony and soft tissue injuries and degenerative processes. Osteoporosis coimnonly manifests in the thoracic spine, with vertebral compression fractures and formation of the dowager s hump, caused by micro fractures of the anterior bodies of the vertebrae leading to a forward bending of the upper thoracic spine. This chapter discusses some of the conditions most commonly affecting the thoracic spine. 

Figure 15.1 Lateral spine X-ray of a 43-year-old man with Paget disease and myopathy shows sclerotic changes of the vertebral body at the level of T7 thoracic vertebral body.

Figure 12.3 (A) Sagittal and (C) axial computed tomography (CT) scans of the thoracic spine performed 6 weeks before the attempted vertebroplasty, demonstrating the presence of pathological compression fractures because of lytic lesions at T5 and superior end plate of T6 (white arrows). (B) Sagittal and (D) axial CT scans of the thoracic spine performed after the attempted vertebroplasty, demonstrating complete remodeling of the vertebral bodies (white arrows). Reprinted with permission from [27]. Copyright 2014 Elsevier.

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