Tsuzuki N, Abe R, Saiki K, Zhongshi L
Department of Orthopaedic Surgery, Saitama Medical Center, Saitama Medical School, Kawagoe, Japan.
Spine (Phila Pa 1976). 1996 Jan 15;21(2):203-11. doi: 10.1097/00007632-199601150-00008.
This study used anatomical and clinical data to analyze the postoperative tension-status of cervical roots after posterior decompression of the cervical spinal cord. The efficacy of longitudinal durotomy with regard to prevention of postoperative palsy was investigated in a controlled study.
To elucidate the mechanism of postoperative radiculopathy and to prevent its occurrence.
Previous anatomical studies by the authors revealed that the posteromedial shift of the dura-root junction following posterior bulging of the cervical dural sac exerted a traction force on the portion of the roots outside the dural sac and reduced the tension on the rootlets inside the dural sac. These traction-related phenomena disappear after longitudinal durotomy.
Lengths of various parts of an anterior root were measured in 20 Japanese adult cadavers. The shortest pre- and postoperative distances between the anterolateral mid-edge of the spinal cord and dura-root junction were compared, using computed tomography-myelograms of postoperative C5 radiculopathies. The effects of longitudinal durotomy were also investigated in a controlled study involving 118 patients with laminoplasty.
The length ratio between the longest and shortest anterior rootlet in each cervical root showed fairly constant values. Clinically, the length of the shortest rootlet could be calculated using a myelogram. Radiographical findings in cases of postoperative radiculopathies suggested increased tension on roots outside the dural sac but not on rootlets inside the dural sac. Application of longitudinal durotomy in a type of lateral opening laminoplasty resulted in the disappearance of postoperative radiculopathy.
An extradural tethering effect was suggested as one mechanism leading to postoperative radiculopathy. Durotomy may be useful in the treatment of postoperative palsy.
本研究利用解剖学和临床数据，分析颈脊髓后路减压术后颈神经根的张力状态。在一项对照研究中，探讨了纵行硬脊膜切开术预防术后麻痹的疗效。
阐明术后神经根病的机制并预防其发生。
作者先前的解剖学研究表明，颈硬膜囊后凸后硬脊膜-神经根交界处的后内侧移位，对硬膜囊外的神经根部分施加了牵引力，并降低了硬膜囊内神经根丝的张力。这些与牵引相关的现象在纵行硬脊膜切开术后消失。
在20具日本成年尸体上测量前根各部分的长度。使用术后C5神经根病的计算机断层扫描脊髓造影，比较脊髓前外侧中缘与硬脊膜-神经根交界处术前和术后的最短距离。在一项涉及118例椎板成形术患者的对照研究中，也对纵行硬脊膜切开术的效果进行了研究。
每个颈神经根中最长和最短神经根丝的长度比显示出相当恒定的值。临床上，最短神经根丝的长度可以通过脊髓造影计算得出。术后神经根病病例的影像学表现表明，硬膜囊外神经根的张力增加，而硬膜囊内神经根丝的张力未增加。在一种外侧开口椎板成形术中应用纵行硬脊膜切开术，可使术后神经根病消失。
硬膜外束缚效应被认为是导致术后神经根病的一种机制。硬脊膜切开术可能对治疗术后麻痹有用。
