C1-C2 stabilization by Harms arthrodesis: indications, technique, complications and outcomes in a prospective 26-case series.
INTRODUCTION
C1-C2 arthrodesis is a surgical challenge due to the proximity of neurovascular structures (vertebral arteries and spinal cord) and the wide range of motion of the joint, hampering bone fusion. A variety of techniques have been successively recommended to reduce anatomic risk and improve results in terms of biomechanical stability and fusion rates. Recently, Harms described a new technique using polyaxial screws in the C1 lateral masses and C2 pedicles.


MATERIAL AND METHOD
The present study reports our experience in a consecutive series of 26 patients operated on by C1-C2 arthrodesis using the Goel and Harms technique, and details technical aspects step by step. Routine systematic immediate postoperative CT and 6-month CT controlled screw positioning and assessed fusion. Follow-up was at least 1 year, except in 2 cases (10 months).


RESULTS
Twenty-six patients with a mean age of 57 years were included. Indications comprised: C2 non-union (n=11), C1-C2 fracture and/or dislocation (n=11), inflammatory pathology (n=2) and tumoral pathology (n=2). The results showed the technique to be reliable (no neurovascular complications and 85% of screws with perfect positioning) and an excellent rate of fusion (100% at 6 months).


CONCLUSION
Anatomic and biomechanical considerations, combined with the present clinical and radiological outcomes, indicate that Goel and Harms fusion is to be considered the first-line attitude of choice for posterior C1-C2 arthrodesis.


LEVEL OF EVIDENCE
Level IV prospective study.
['Bourdillon|P|P|', 'Perrin|G|G|', 'Lucas|F|F|', 'Debarge|R|R|', 'Barrey|C|C|']
D000293:Adolescent D000328:Adult D000368:Aged D001268:Atlanto-Axial Joint D001863:Bone Screws D005260:Female D006801:Humans D007593:Joint Instability D008297:Male D008875:Middle Aged D011446:Prospective Studies D011859:Radiography D013123:Spinal Fusion D055815:Young Adult
Harms C1-C2 fusion C1-C2 instability C1-C2 screws Cervical fusion Cervical spine arthrodesis