Objective: The atlantoaxial complex exhibits unique morphological and biomechanical characteristics. Trauma, tumors, and inflammatory or congenital diseases may compromise the stability of this joint. The purpose of this study was to describe a minimally invasive surgical (MIS) technique for C1-C2 fixation through an anatomical corridor and to analyze the clinical, surgical, and fusion outcomes using this approach over a 15-year period.Methods: We present a MIS technique utilizing a natural anatomical corridor for C1-C2 screw fixation, which has been used at our institution since 2007. We analyzed the demographic characteristics and clinical results of the patients who underwent this procedure.Results: Forty-seven patients underwent C1-C2 MIS screw fixation during the study period, with 24 male patients and a median age of 66 years. The indication for surgery was atlantoaxial subluxation in 60% of cases and odontoid fracture in 23%. The median surgery duration was 130 minutes, with a median blood loss of 300 mL. There were no intraoperative complications, and only one patient presented with a superficial wound infection, which was successfully treated with antibiotics.Conclusion: The minimally invasive approach through a natural anatomical corridor to fuse the atlantoaxial joint using C1 lateral masses and C2 pedicle screws bilaterally has been demonstrated to be safe and effective. Preserving the occipital-cervical tension band provides additional biomechanical stability to the construct.

Objective: Chiari malformation type 1 (CM1) is a congenital hindbrain abnormality characterized by downward displacement of the cerebellar tonsils through the foramen magnum. The widespread accessibility of advanced technologies and imaging modalities has led to an increase in the popularity of minimally invasive (MIS) techniques in cranial and spinal pathologies. Methods: The study was conducted at a university hospital in Bogotá, Colombia. All data were obtained from the database of the hospital’s Neurosurgery Department. After institutional review board approval, the medical records of patients who underwent MIS posterior fossa decompression for CM1 were retrospectively reviewed.Results: Thirty-six patients underwent posterior fossa decompression through a minimally invasive approach during the study period. Nineteen patients met the inclusion criteria and were included in the data analysis. The patients’ chief complaints were headache (78.9%) and neck pain (57.9%). The average surgical time was 158.2 ± 50.5 minutes, with no significant difference in timing among different specialists. The most common postoperative complications were associated with dura closure, including 6 patients with pseudomeningocele and one patient with cerebrospinal fluid leak.Conclusion: Different surgical techniques have been proposed for posterior fossa decompression of CM1. In the present study, we favor a minimally invasive approach to the craniocervical junction to preserve as much of the normal anatomy as possible and avoid alterations in spinal biomechanics.