Image guided percutaneous trans-pedicular screw fixation of the thoracic spine. A clinical evaluation.

Objective: We report our preliminary experience with a minimally invasive image guided percutaneous trans-pedicular fixation technique of the thoracic spine in patients with significant co-morbidity. This study aims to demonstrate the feasibility and efficacy of the presented operative technique as well as to detect potential drawbacks.

Method: A navigated percutaneous application of trans-pedicular screws was performed in 14 patients with radiological validated instability of the thoracic spine and significant medical co-morbidity. Due to poor bone quality, vertebroplasty of the affected levels had to be performed in nine patients. The levels involved were (T9-12) in ten patients, the middle (T5-8) in two patients and the upper thoracic (T1-4) segments in two others. VAS scores for local back pain were used to assess clinical outcome.

Results: A total of 56 screws were inserted. There was no additional morbidity associated with the procedure. Post-operative CT scans and plain X-rays were obtained in all patients. In 2 (3.5%) medial penetration of the pedicle border occurred without neurological sequelae for the patient. Reduction of VAS scores regarding back pain during the first post-operative week was noted. Follow up ranged between 6 months and 12 months.

Conclusion: Navigated percutaneous trans-pedicular fixation of the thoracic spine is feasible and can be performed safely in patients where open surgery is of significant risk. Pre-operative planning is essential in order to avoid intra-operative complications with the instrumentation system.