Introduction: Multilevel posterior cervical instrumented fusions are becoming more prevalent in current practice. Biomechanical characteristics of the cervicothoracic junction may necessitate extending the construct to upper thoracic segments. However, pedicle screw fixation in upper thoracic spine can be technically demanding owing to transitional anatomy while improper placement risks vascular and neurologic complications. Thoracic instrumentation methods include free-hand with or without laminotomies, fluoroscopic guidance, and CT-based image guidance. However, fluoroscopy of upper thoracic spine is challenging secondary to patient size, positioning, and vertebral geometry, while image-guided systems are not readily available at most centers due to cost. Additionally, imaging modalities increase radiation exposure to the patient and surgeon while potentially lengthening surgical time. We propose a novel and accurate method for T1 pedicle screws devoid of imaging or extra bone removal and present our experience with 37 consecutive patients.

Methods: A retrospective review of 37 consecutive patients who underwent cervicothoracic fusion by a single surgeon utilizing a novel free-hand T1 pedicle screw technique between Jan 1, 2010 and Oct 30, 2012. A starting point medial and cephalad to classical entry as well as a new screw trajectory were implemented. No imaging modalities were employed during screw insertion. Postoperative CT scan was obtained on day 1. Thoracic screw accuracy was independently evaluated by senior neurosurgeon and a neuroradiologist according to the Heary classification.

Results: Thirty seven consecutive patients had 73 pedicle screws placed at T1. Heary Grade 1 was achieved in 82.2%(60/73), Grade 2 in 5.5%(4/73), Grade 3 in 9.6%(7/73), Grade 4 in 2.7%(2/73), both <2mm. No Grade 5 screws or revision procedures occurred. No new neurological deficits were appreciated postoperatively.

Conclusions: This modification of the classical starting point and trajectory mitigates additional bone removal or imaging modalities while maintaining a high accuracy rate of successful screw placement compared to historical controls.

Patient Care: Our technique simplifies placement of upper thoracic pedicle screws as an adjunct to multilevel posterior cervical fusion constructs. This improves the biomechanical stability across the cervicothoracic junction and may achieve a greater clinical outcome. In our hands, this technique reduces both operative time as well as radiation exposure to the patient without sacrificing placement accuracy.

Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the importance of supplementing multilevel cervical constructs with thoracic instrumentation 2) Discuss, in small groups, various available methods for upper thoracic pedicle instrumentation 3) Identify an effective treatment for improperly placed cervical or upper thoracic pedicle screw

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