THE RELATION BETWEEN THE OSTEO-FIBROUS CANAL OUTSIDE OF THE LUMBAR SPINAL CANAL AND THE SPINAL NERVE PASSING THROUGH IT. Ⅰ. THE MORPHOLOGY OF THE OSTEO-FIBROUS CANAL OF THE MEDIAL DIVISION OF POSTERIOR RAMUS OF THE LUMBAR NERVE WITH SPECIAL REFER / 解剖学报

ABSTRACT

1. 40 cadavers were dissected in order to observe the position and formation of the osteo-fibrous canal (384 canals) of the medial division of posterior ramus of lumbar nerves together with the occurrence of the articulo-accessory (process) ligament.2. The form of the external opening of the osteo-fibrous canal may be classified into three groups; nearly circular 35.1% (151); approximately ellipsoid 32.3% (124); crack detector 28.4% (109).3. The osteo-fibrous canal consists of four walls, bounded by mammillary process, accessory process, bony wall and superior articular process ligament respectively. According to the constitution of the anterior and posterior walls of the canal, it may be divided into three categories; osteo-aponeuroticoligamentous type 29.4% (113); osteo-membranous type 66.4% (255) and bony type 4.2% (16).4. The length and width of the superior articular process ligament were measured. The sexual difference of the lengths of L_(1～5) lumbar is significant.5. The sulcus between the superior articular process and the alar portion of the sacrum was observed and measured.6. The ligament on the posterior wall of the canal is nominated as the ligament of the superior articular process.7. Based on the anatomical structures thus studied, some clinical significances were discussed.