Thoracic Spine – Posterolateral Approach

Modern Study Review (AI-Generated)

High-Yield Summary

The posterolateral thoracic spine approach via costotransversectomy offers direct access to anterior and lateral vertebral body pathology without entering the thoracic cavity. It is primarily indicated for tumor resection, infection, and decompression when anterior approaches are contraindicated or limited. While still valuable in complex open cases, this approach is increasingly supplemented or replaced by minimally invasive and thoracoscopic techniques in select patients.

Applied Anatomy & Intervals

Internervous Interval

• None: Dissection proceeds through muscle fibers and subperiosteal planes without a true internervous plane.

Anatomic Landmarks

• Spinous process of the involved vertebra (midline palpable landmark)
• Transverse process (TP) of the target vertebra
• Rib corresponding to the vertebral level (typically 6–8 cm lateral to midline)

Patient Positioning & Setup

• Table Type: Radiolucent spinal or Jackson table preferred for prone positioning and intraoperative imaging.
• Patient Position: Prone with longitudinal bolsters to allow abdominal free-hanging and minimize venous congestion.
• Specialized Equipment:
• C-arm fluoroscopy positioned for lateral and AP thoracic spine views
• Standard spinal instrumentation and retractors

Surgical Technique (The “Vital Steps”)

Incision & Superficial Dissection

• Curved linear incision ~8 cm lateral to the spinous process at the target level
• Incise skin, subcutaneous fat, and thoracolumbar fascia in line with the skin incision
• Divide trapezius muscle fibers longitudinally, preserving neurovascular structures

Deep Dissection & Exposure

• Identify and expose the posterior aspect of the rib at the target level
• Perform subperiosteal dissection to detach all muscle attachments from the rib
• Dissect laterally along the superior border and medially along the inferior border of the rib
• Osteotomize the rib approximately 6–8 cm from midline; detach remaining muscle attachments and remove the rib segment
• Remove muscle attachments from the transverse process
• Resect the transverse process at its junction with the lamina and pedicle
• Enter the retropleural space by blunt digital dissection
• Carefully elevate the parietal pleura off the vertebral body to expose the anterior column

The “Danger Zone”

Post-Operative Pearl

Early mobilization is encouraged; however, avoid excessive lateral bending or rotation that stresses the rib resection site. Monitor closely for signs of pneumothorax or cerebrospinal fluid leak.

Classic Clinical Notes

Thoracic spine – posterolateral approach

Costotransversectomy

• Position: Prone with bolsters positioned longitudinally.
• Incision: Curved linear incision about 8 cm lateral to the appropriate spinous process.
• Internervous Plane: None.
• Dissection:
• Incise subcutaneous fat and fascia in line with skin incision.
• Cut through trapezius in line with fibers close to transverse processes.
• Cut down to posterior aspect of rib to be resected.
• Separate all muscle attachments from rib subperiosteally.
• Dissect laterally along superior border of rib and medially along inferior border.
• Divide rib about 6–8 cm from midline.
• Detach any remaining muscle and twist rib’s medial end to complete resection.
• Remove muscle from transverse process.
• Remove transverse process at junction with lamina and pedicle.
• Enter retropleural space by digital palpation.
• Remove parietal pleura from vertebral body.
• Dangers:
• Dura: If dissection is extensive around vertebral body and central canal entered.
• Intercostal artery: Safe with subperiosteal dissection.
• Pleura: Initially use blunt dissection.

Last Updated on January 25, 2026 by orthonet