经胸椎肋横突结合区椎弓根外螺钉固定的解剖学研究

Anatomy of the extraspedicular screw fixation through costotransverse unit of thoracic vertebrae

目的:为经胸椎肋横突结合区椎弓根外螺钉固定手术提供影像解剖学参数。方法:对50个正常成人的T1～10肋横突结合区进行CT扫描,测量肋横突结合区入路的长度、宽度、高度、内倾角度及下倾角度,并与椎弓根入路对比,数据经统计学处理。根据测量结果设置各椎体入路穿钉参数,在3具成人防腐尸体标本T1～10共30个胸椎体上进行模拟手术,穿钉后CT扫描。结果:肋横突结合区入路进钉长度(59.05±0.83)mm、宽度(15.03±0.73)mm、高度(10.36±1.28)mm、内倾角度(34.53±0.21)°及下倾角度(12.95±1.58)°均大于椎弓根入路进钉长度(45.51±0.56)mm、宽度(5.98±0.78)mm、高度(5.35±0.61)mm、内倾角度(12.31±2.05)°及下倾角度(2.85±1.07)°,差异有统计学意义(P<0.05);根据测量结果设置进钉入路参数,30个胸椎体60枚螺钉均位于肋横突结合区,未见穿入椎管、椎间孔和胸腔。结论:胸椎肋横突结合区螺钉内固定,在解剖学上是可行的,尤其对椎弓根发育畸形和狭窄者,具有安全、可靠、容易定位等优点,为胸椎后路螺钉固定的选位提供参考。

Objective： To provide anatomic data for extranspedicular screw fixation through costotransverse unit of thoracic vertebra. Methods： The length, width, height, the introversion and declination angles of T11～0 costotransverse units approach were measured and analyzed on CT images of 50 adult normal. The parameters of the screw insertion were determined based on the above results, and then simulating operation were proceeded on 3 adult cadavers under the guide of CT. Results： The length, width, height, the introversion and declination angles of T1～10costotransverse unit approach were （59.05±0.83）mm,（ 15.03±0.73 ） mm, （10.36±1.28）mm,（34.53±0.21 ）~and （12.95±1.58）mm respectively, which were more exceed comparing to that of the transpedicular approach of （45.51±0.56）mm,（5.98±0.78 ）ram, （5.35±0.61）mm,（ 12.31±2.05 ）°and （2.85±l.07）°respectively （P〈0.05）. 60 screws penetrated on 30 thoracic vertebrae successfully. All screws were within the pedicle rib unit, and did not reach spinal canal, intervertebral foramen or pleura. Conclusions： The extrapedicular screw fixation through costotransverse unit of thoracic vertebrae is a reliable approach, which is one of selections for the treatment of malformation and narrow of vertebral arch.