Objective: To summarize the relationship between shoulder instability and superior labrum anterior posterior (SLAP) lesion.
Methods: The characteristics of shoulder instability and SLAP lesion were analyzed, and the relationship between them in pathogenesis, clinical symptoms, and biomechanics was discussed by referring to relevant domestic and foreign literature.
Results: Shoulder instability and SLAP lesion can occur both spontaneously and respectively. SLAP lesion destroys the superior labrum integrity and the long head of biceps tendon (LHBT) insertion, causing excessive humeral head displacement against glenoid, and leading to shoulder instability. While chronic repetitive or acute high-energy traumatic shoulder instability can in turn aggravate SLAP lesion, resulting in expansion and increased degree of the original lesion.
Conclusion: SLAP lesion destroys mechanisms of shoulder stability, while shoulder instability causes tears of the upper labrum and the LHBT, showing a connection between shoulder instability and SLAP lesion. However, the existing evidence can only demonstrate that shoulder instability and SLAP lesion induce and promote the development of each other, instead of a necessary and sufficient condition. Therefore, the specific causal relationship between the two remains unknown and needs to be further studied.
目的: 总结肩关节不稳与上盂唇自前向后（superior labrum anterior posterior，SLAP）损伤的联系。.
方法: 通过查阅国内外相关研究文献，分析肩关节不稳与SLAP损伤的特点，归纳并探讨两者在发病机制、临床症状及生物力学上的关联。.
结果: 肩关节不稳和SLAP损伤既可同时存在，也可单独发生。SLAP损伤由于破坏了上盂唇的完整性和肱二头肌长头腱（long head of biceps tendon，LHBT）止点，可引起肱骨头相对关节盂过度移位，导致肩关节不稳。而慢性反复性或急性高能量创伤导致的肩关节不稳也会加重SLAP损伤，造成原有损伤范围扩大及撕裂程度加重。.
结论: SLAP损伤会破坏肩关节稳定机制，肩关节不稳会引起上盂唇和LHBT撕裂，两者间存在一定联系。然而，现有研究结果仅能证明肩关节不稳和SLAP损伤之间具有互相诱发和促进发展的关系，而非互为充分必要条件，因此两者间具体因果关系还需进一步深入研究。.
Keywords: Shoulder instability; glenoid labrum; long head of biceps tendon; superior labrum anterior posterior lesion.