Nasu Hisayo, Baramee Phichaya, Kampan Natnicha, Nimura Akimoto, Akita Keiichi
Department of Clinical Anatomy, Graduate School of Medical and Dental Sciences Tokyo Medical and Dental University, Tokyo, Japan.
Department of Functional Joint Anatomy, Graduate School of Medical and Dental Sciences Tokyo Medical and Dental University, Tokyo, Japan.
JSES Open Access. 2019 Mar 15;3(1):5-11. doi: 10.1016/j.jses.2019.01.001. eCollection 2019 Mar.
Posterior shoulder instability was reported to be more common than had been previously reported. However, the detailed morphology of the origin of the long head of the triceps brachii (LHT), which is located at the posteroinferior part of the glenohumeral joint and associated with the stability of the head of the humerus, has been unknown. The purpose of the current study was to clarify the detailed morphology of the origin of the LHT.
A total of 64 specimens from 36 cadavers (11 males and 25 females) were used. After dissecting the origin of the LHT in 54 specimens of 27 cadavers, the width of the origin of the LHT was measured with a caliper by 2 observers. The origin of the LHT was also investigated histologically in 18 specimens. Sections were analyzed with Masson's trichrome staining and Safranin O staining.
Some fibers of the LHT originated more from the cranial area than from the infraglenoid tubercle and descended along the posterior rim of the glenoid cavity. The width of the origin on the dorsal surface of the scapula was 31.2 mm. The origin from the bone had a developed uncalcified fibrocartilage histologically. In addition, the LHT was fused with the glenohumeral joint capsule and was attached to the glenoid labrum directly.
The LHT could affect the glenohumeral joint capsule or the glenoid labrum because of their connections to each other and be associated with the posterior shoulder instability indirectly.
据报道，肩后不稳比之前报道的更为常见。然而，肱三头肌长头（LHT）起点的详细形态一直未知，该起点位于盂肱关节的后下部，与肱骨头的稳定性相关。本研究的目的是阐明LHT起点的详细形态。
使用了来自36具尸体（11例男性和25例女性）的64个标本。在27具尸体的54个标本中解剖LHT的起点后，由2名观察者用卡尺测量LHT起点的宽度。还对18个标本进行了LHT起点的组织学研究。切片用Masson三色染色和番红O染色进行分析。
LHT的一些纤维更多地起源于颅骨区域而非盂下结节，并沿关节盂后缘下行。肩胛骨背侧起点的宽度为31.2mm。从组织学上看，骨起源处有发达的未钙化纤维软骨。此外，LHT与盂肱关节囊融合，并直接附着于关节盂唇。
LHT可能因其与盂肱关节囊或关节盂唇的相互连接而影响它们，并间接与肩后不稳相关。
