Sun Yucheng, Kwak Jae-Man, Zhou Youlang, Fu Yan, Wang Zhe, Chen Qingzhong, Jeon In-Ho
Department of Hand Surgery, Affiliated Hospital of Nantong University, College of Medicine, University of Nantong, Nantong, China.
Department of Orthopedic Surgery, ASAN Medical Center, College of Medicine, University of Ulsan, Seoul, South Korea.
J Orthop Translat. 2020 Mar 5;27:153-160. doi: 10.1016/j.jot.2020.02.006. eCollection 2021 Mar.
We designed a paired controlled study to investigate the role of the suprascapular nerve (SSN) in rotator cuff healing using a rat tear model, and we hypothesised that rotator cuff healing is impaired in the absence of a healthy SSN.
Bilateral supraspinatus tenotomy from the great tuberosity was performed for 36 Wistar rats, which was then repaired immediately. A defect on the SSN was made on the right side, and a sham surgery was performed on the SSN at the left side. Twelve rats were sacrificed for biomechanical (six rats) and histological (six rats) testing, evaluated at 3, 6, and 9 weeks after surgery.
The bone-tendon junction on the nerve-intact side showed significantly better biomechanical characteristics than the nerve-injured side in terms of maximum load, maximum stress over time, stiffness at 9 weeks, and Young's modulus at 3 and 9 weeks. On the nerve-injured side, significantly smaller fibrocartilage layers and muscle fibres could be obtained over time. In addition, on the nerve-injured side, inferior bone-tendon interface formation was obtained in terms of cell maturity, cell alignment, collagen orientation, and the occurrence of tidemark and Sharpey's fibres through 9 weeks. In addition, neuropeptide Y was secreted in the nerve-intact group at 6 and 9 weeks.
This study showed the inferior healing of the bone-tendon junction on the nerve-injured side compared with the nerve-intact side, which indicates that the SSN plays an important role in rotator cuff healing. Surgeons should pay more attention to SSN injury when treating patients with rotator cuff tear.
我们设计了一项配对对照研究，使用大鼠肩袖撕裂模型来研究肩胛上神经（SSN）在肩袖愈合中的作用，并且我们假设在缺乏健康的SSN时肩袖愈合会受损。
对36只Wistar大鼠进行双侧从大结节处切断冈上肌肌腱的操作，然后立即进行修复。在右侧制造SSN缺损，在左侧对SSN进行假手术。在术后3、6和9周处死12只大鼠进行生物力学（6只大鼠）和组织学（6只大鼠）测试。
在最大负荷、随时间变化的最大应力、9周时的刚度以及3周和9周时的杨氏模量方面，神经完整侧的骨 - 肌腱结合处显示出比神经损伤侧明显更好的生物力学特性。随着时间的推移，在神经损伤侧可获得明显更小的纤维软骨层和肌纤维。此外，在神经损伤侧，在9周内，就细胞成熟度、细胞排列、胶原纤维方向以及潮线和沙比纤维的出现情况而言，骨 - 肌腱界面形成较差。此外，在6周和9周时，神经完整组分泌神经肽Y。
本研究表明，与神经完整侧相比，神经损伤侧的骨 - 肌腱结合处愈合较差，这表明SSN在肩袖愈合中起重要作用。外科医生在治疗肩袖撕裂患者时应更加关注SSN损伤。
