Minimally invasive posterior transarticular stand-alone screw instrumentation of C1-C2 using a transmuscular approach: a technique description and results comparing with posterior midline exposure.

PURPOSE: The aim of this study was to compare feasibility, safety, and fusion results of posterior transarticular stand-alone screw (SAS) instrumentation of C1-C2 with a minimally invasive technique to that with posterior midline exposure.

METHODS: Between 2008 and 2016, 164 patients underwent surgical treatment for traumatic injuries to the upper cervical vertebrae at our institution. We included 38 patients (27 men and 11 women; age range, 17-81 years) in present study. The posterior midline approach (PMA) group (23 patients) included patients who underwent surgery using a conventional midline incision following percutaneous screw insertion. The transmuscular approach (TMA) group (15 patients) included patients who underwent SAS fixation using a minimally invasive technique. The mean follow-up period was 58 months (range; 12-118).

RESULTS: Statistical analysis revealed that the operative time, blood loss volume, and severity of postoperative pain were lower in the TMA group. No significant excess of radiation exposure to surgical team and the patient occurred in TMA group compared to that in PMA group. C1-C2 fusion was observed in 37 patients. Stable fibrous fusion between C1 and C2 vertebrae was found in 1 patient.

CONCLUSIONS: A minimally invasive technique using a paravertebral transmuscular approach provides an alternative to routine posterior transarticular SAS fixation of C1 and C2 through a posterior midline approach. The minimally invasive technique reduces the duration of surgery and the volume of blood loss, decreases the severity of postoperative pain, and does not increase the amount of radiation exposure for the surgical team and the patient.