Costotransversectomy Approach

The chest wall has two muscular layers. The outer layer is made by the trapezius and Lattisimus dorsi muscle. Deep to this layer lies the Serratus Anterior and Rhomboid muscles, which cover the ribs, and the intercostal muscles. The internal and external intercostals span the intercostal space. The neuro vascular bundle lies in the inferior aspect of the rib, in the intercostal groove. The superior most structure is vein, then there is the intercostal artery and most caudally there is intercostal nerve. The parietal pleura lie deep to the intercostal muscles and the visceral pleura envelopes the Lung. The sympathetic chain lie anterior to the transverse process, the greater splanchic nerve arises from the sympathetic chain in the mid thoracic region and enters the abdomen piercing the diaphragm. The segmental vessels lie directly over the vertebral column posterior to the sympathetic chain and continues as the intercostal vessels.

Can be done in either prone or a floppy lateral position about 20 degrees lateral decubitus position.

The bolsters should be so placed so as to allow adequate chest expansion especially in the prone position.

Exposure:

Incision: Usually longitudinal para spinal incision is preferred especially when a decompression and interbody fusion is planned, how ever depending on the pathology even a midline or a transverse para spinous incision may be used.

A curvi linear skin incision centered about four fingers from midline of the desired vertebrae and curving toward midline caudally and cephalad is made.

A cautery is used to cut the para spinal muscle and thoracolumbar fascia. A cobbs elevator is used to separate the muscle attachment from the lamina. A sharp periosteal dissection is carried out to separate the periosteum from the rib.

The Costotransverse joint is incised, the periosteum of the rib is elevated

Circumferentially with especial care being taken during the subperiosteal elevation of the anterior periosteum as the pleura lies immediately behind the rib bed.

The neurovascular bundle traverses the lower edge of the rib after leaving the intervertebral foramen located at the caudal aspect of transverse process, it should be identified and preserved.

The rib is cut laterally at the angle of rib and lifted off its bed. This allows the dissection of the parietal pleura and endothoracic fascia under vision. The rib should be disarticulated from the costovertebral joint. A self-retaining retractor or a rib spreader can be used to improve the exposure.

A sharp dissection at the base of transverse process leads onto the pedicle and the vertebral body. The exiting nerve root can be identified at the foramen. The nerve can be dissected medially applying a gentle medial traction. The dural sac will be visible medially.

After the dural sleeve and nerve root is adequately visualized and protected, the decompression may be carried out removing the pedicle, the lamina, and vertebral body.

While dissecting anterior to the vertebral body it is imperative to elevate the prevertebral fascia off the body to protect the anterior structures.

The closure can be performed in layers: fascia, sub cutaneous tissue and skin.

Potential complication:

Injury to neurovascular bundles.

Injury to pleura.

Lung contusion.

Injury to great vessels lying anterior to the vertebral body.

Dural tears.

Postoperative atelectasis of lung.

Infection.