Introduction: Posterior C1-2 instrumentation is often associated with excessive bleeding, especially when the venous plexus between C1-2 lateral masses is disrupted. As an attempt to reduce intraoperative bleeding we describe a novel variation to the Harms C1-2 instrumentation procedure.
Methods: A retrospective chart of thirteen cases employing this tehnique was performed. The functional outcome assessment was evaluated using the neck disability index (NDI) and visual analog scale (VAS) at pre-operative, 6-weeks, 6-months and 1-year post-operative. Univariate analysis of demographics, estimated blood loss (EBL), body mass index (BMI) and peri-operative complications were analyzed.
Surgical technique consisted in sub-periosteal blunt dissection carried from the C2 lamina to the lateral mass and pars of C2 upward towards the C1-2 joint and C1 lateral mass. This maneuver allowed for the elevation of the C2 nerve root along with the venous plexus without disrupting it after which the usual steps in the Harms technique were followed.
Results: Thirteen patients (5 males, 8 females) were operated using this technique with average age 55, average BMI 25, and average hospital length of stay of 4 days. The average length of surgery was 203 minutes and the average estimated blood loss was 114cc. Instability due to rheumatoid arthritis and tumors were the most common diagnosis, and we had no intraoperative complications.
The average NDI and VAS at pre-operative compared to 6-weeks and 6-months was not statistically significant. The average NDI and VAS at pre-operative compared to 1-year post-operative was found to be statistically significant (p=0.003 and p=0.009 respectively).
Conclusions: We present a variation to the Harms technique that can help surgeons minimize venous plexus bleeding in an usually bloody approach. The patients who underwent this modified technique showed similar improvement in VAS and NDI as previously published but we present significant decreased blood loss as compared to the published standard.
Patient Care: This could provide surgeons with a way to lessen blood loss in this type of operation.
Learning Objectives: 1) Be familiar with the Harms technique as well as variations to it
2) Be more familiar with C1-C2 anatomy
3) Be more familiar with the surgical challenges and pitfalls of operating in this area
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