Comparison of Morphometric Measurements of Raditional Posterior Cervical Screw and Paravertebral Foramen Screw in Chinese Population.

STUDY DESIGN A morphometric measurement stydy. OBJECTIVE To measure the length and angle parameters of the screw paths of pedicle screws (PS), lateral mass screws (LMS) and paravertebral foramen screws (PVFS) of subaxial cervical spine in Chinese population. SUMMARY OF BACKGROUND DATA Aramomi proposed a novel internal fixation technology, named PVFS, as an alternative to LMS and PS for subaxial cervical vertebrae (C3-C7). METHODS This study measured the length and medial angles of screw paths on the three-dimensional reconstruction model of cervical computerized tomography (CT) data of 50 patients (25 males and 25 females) in our hospital from January 2018 to June 2018. RESULTS In general, the optimum length and medial angle of the PVFS in Chinese population were 10.65 mm and 21.12° at C3; 10.12 mm, 22.62° at C4; 9.82 mm, 23.66° at C5; 9.19 mm, 24.13° at C6; 9.10 mm, 27.54° at C7. The optimum length and medial angle of PS in Chinese population were 30.94 mm, 33.92° at C3; 30.50 mm, 34.95° at C4; 31.92 mm, 33.42° at C5; 30.50 mm, 31.94° at C6; 29.87 mm, 31.01° at C7. The optimum lengths of LMS paths in Chinese population were C3, 14.84 mm; C4, 15.33 mm; C5, 15.44 mm; C6, 14.74 mm; C7, 14.06 mm. CONCLUSION Although the length of PVFS is limited, it still can be used as an effective substitute for LMS and PS. The PVFS does not have the risk of directly injuring the vertebral artery, its safety angle of insertion is large, and it has higher surgical safety. LEVEL OF EVIDENCE 3.