Pc-aided evaluation for optimum screw insertion in lateral mass of C1: An anatomical research.
Arch Orthop Trauma Surg. 2017 Jun;137(6):817-822
Authors: Krassnig R, Orlandi JA, Tackner E, Hohenberger G, Puchwein P
INTRODUCTION: Movement preserving methods in C1 ring fractures are more and more used particularly in younger sufferers. Subsequently, lateral mass screws are inserted within the first vertebra and related by a rod. The aim of this research was to find out protected zones concerning the vertebral arteries and the medulla oblongata for optimum lateral mass screw positioning when fusing the C1-ring.
MATERIALS AND METHODS: Photos of the cervical backbone of 50 sufferers (64-line CT scanner) have been evaluated and digital screws have been positioned in each lateral plenty of the primary vertebra utilizing 3D-reconstructions of CT scans. The size of the screws, the insertion angles in two planes, the space to the vertebral artery, and the spinal canal was investigated. Descriptive statistics was used and gender-dependent variations have been calculated utilizing scholar t-test. A diameter of four mm was chosen for the screws.
RESULTS: The imply screw size was 30.zero?±?2.three mm on the correct and 30.1?±?2.1 mm on the left facet. The arithmetic imply for the transverse angle was 16.four?±?5.6° on the correct and 15.6?±?6.three° on the left, the sagittal angle averaged eight.three?±?three.eight° on the correct, and 11.zero?±?four.9° on the left facet. The imply distance between screw and spinal canal has been decided on the correct with 2.four?±?zero.7 mm and a pair of.2?±?zero.6 mm on the left facet. The gap from the C1 lateral mass screw to the vertebral artery was on common 7.1?±?1.5 mm on the correct facet (vital correlation with gender, p worth: zero.03) and seven.four?±?1.four mm on the left facet.
CONCLUSIONS: Screws needs to be positioned with a barely converging angle of 16° and a barely ascending angle of 10°. Because of the required excessive precision method intraoperatively multiplanar 2 D or three D imaging is beneficial to keep away from hurt to the vertebral artery or the spinal canal.
PMID: 28357498 [PubMed – indexed for MEDLINE]