目的  扫描电子显微镜下观察犬寰枕间隙肌硬膜桥与硬脊膜及寰枕后膜的连接方式。  方法  取6份犬枕下寰枕间隙组织进行扫描电子显微镜观察，记录并拍摄犬头后小直肌肌硬膜桥纤维与寰枕后膜及硬脊膜纤维的连接关系，分析肌硬膜桥与寰枕后膜及硬脊膜的纤维连接形式。  结果  于寰枕间隙，肌硬膜桥纤维存在于头后小直肌与寰枕后膜，及寰枕后膜与硬脊膜之间。由犬头后小直肌腹侧发出的肌硬膜桥纤维平行排列，以锐角汇入寰枕后膜，并延续为寰枕后膜背侧浅层；寰枕后膜腹侧发出的与硬脊膜连接的肌硬膜桥纤维分成多束，束外有被膜包裹，内部纤维平行排列。寰枕后膜与硬脊膜之间的肌硬膜桥纤维最终以“编织”的方式汇入硬脊膜浅层，参与硬脊膜的构成。  结论  肌硬膜桥纤维与硬脊膜纤维以编织的方式相连接，提示肌硬膜桥纤维可以有效地传递拉力。

Objective  To observe the form of fibers connection of myodural bridge (MDB) between the rectus capitis posterior minor muscle (RCPmi) and the posterior atlanto-occipital membrane (PAOM), the PAOM and the spinal dura mater (SDM) in the atlanto-occipital space of dogs with scanning electron microscope (SEM).   Methods  The dense connection tissues (MDB) among the RCPmi, PAOM and SDM of six dogs were scanned with a SEM. The form of fibers connection between the RCPmi and PAOM, the PAOM and SDM in the atlanto-occipital space was observed, photographed, and documented.   Results  The MDB fibers connection existed between the RCPmi and the PAOM, and between the PAOM and the SDM. The MDB fibers between the RCPmi and the PAOM were parallelly arranged and inserted into the PAOM at an acute angle, and continued into the superficial layer of the back of PAOM. The MDB fibers between the PAOM and the SDM converged into several bundles. Each MDB bundle was covered by membrane. This membrane became continuous with the superficial membrane of SDM, meanwhile fibers of the membrane were interwoven with the surface fibers of SDM.   Conclusion  The interweaving fibers of the MDB with the SDM indicates that MDB fiber may withstand great tension.