Minimally invasive tubular access for posterior cervical foraminotomy with three-dimensional microscopic visualization and localization with anterior/posterior imaging.

BACKGROUND CONTEXT Posterior cervical foraminotomy allows decompression of the nerve root with preservation of motion. A previously described endoscopic technique utilizes minimally invasive muscle splitting with routine outpatient discharge. PURPOSE The approach allows a modified tubular retraction system to be used with three-dimensional visualization and anterior/posterior fluoroscopic imaging, thus allowing easy visualization even in large patients. This approach also allows safe docking of the retractor system on the lateral mass, thus avoiding the cervical spinal canal during exposure. STUDY DESIGN Prone position is utilized, with localization and docking of instrumentation accomplished with anterior/posterior fluoroscopy. Surgery is performed with microscope-facilitated, three-dimensional visualization. METHODS Patients were placed in the prone position. Spinal needle localization was used for initial localization followed by a stab wound and placement of a 14-mm tube using sequentially enlarging dilators. Frequent use of anterior/posterior fluoroscopy avoided inadvertent medial placement of the instruments in the canal. A standard neurocapable operating microscope was used with 10X magnification and 400-mm focal length. RESULTS A new minimally invasive posterior cervical approach was performed on 222 patients without dural penetration. CONCLUSIONS Posterior foraminal cervical surgery with three-dimensional access and localization with anterior/posterior fluoroscopic imaging allows safe, reproducible docking on the cervical spine with subsequent exploration of the foramen and routine outpatient discharge. Complications related to difficulty with lateral localization in the lower cervical spine, and with inadvertent entry into the cervical spinal canal with possible catastrophic result are thus avoided.