Surgical outcome of type II odontoid fracture, Harms technique

Abstract

Abstract Background Cervical trauma is a common cause of disability following spinal cord injury especially in athletic populations. The biomechanics in the atlantoaxial joint carry more than 50% of the rotational movement which can be affected in transverse ligament tear associated with odontoid fracture type II. Odontoid fracture type II is considered an unstable fracture with a high rate of nonunion in conservative treatment. Limitation of the odontoid screws in some cases gives the chance of posterior cervical fixation to have the superior role. Use of polyaxial screws in Harms technique gives the best results in maintaining majority of the biomechanics. Purpose Our aim in this study is to evaluate Harms technique in patients regarding pain improvement and restoration of the motor power and to report the complications. Study design This is a retrospective case series study. We used the Frankel grading system to evaluate the postoperative neurological state. Patient and methods Between January 2015 and January 2018, 12 patients were introduced to the neurosurgical department at the Sohag University Hospital with post-traumatic type II odontoid fracture with failure of conservative treatment and not suitable for anterior odontoid screws. All patients underwent full laboratory, medical, and neurological evaluation and imaging study on the cervical spine. All patients underwent posterior cervical fixation C1–C2 by polyaxial screw Harms technique. Results Male ratio was predominant in our study: 75% with a mean age 34.4 years. Neck pain with limitation of the neck movement was the complaint for the all cases. Three cases came with neurological affection. Postoperative superficial infection reported in one patient; no vertebral artery or neural injuries were noticed in our study. Conclusion Harms technique C1–C2 fixation is a valuable choice in patients with type II odontoid fracture with failure of conservative treatment or not suitable for odontoid screw. Harms technique gives us the highest preservation of the biomechanics among the other posterior approaches. Trial registration NCT03768843.

Keywords

• Harms technique
• Odontoid fracture
• Polyaxial screws
• Transarticular