Recurrent posterior glenohumeral instability is an entity that demands a high clinical suspicion and a detailed study for a correct approach and treatment. Its classification must consider its biomechanics, whether it is due to functional muscular imbalance or to structural changes, volition, and intentionality. Due to its varied clinical presentations and different structural alterations, ranging from capsule-labral lesions and bone defects to glenoid dysplasia and retroversion, the different treatment alternatives available have historically had a high incidence of failure. A detailed radiographic assessment, with both CT and MRI, with a precise assessment of glenoid and humeral bone defects and of glenoid morphology, is mandatory. Physiotherapy focused on periscapular muscle reeducation and external rotator strengthening is always the first line of treatment. When conservative treatment fails, surgical treatment must be guided by the structural lesions present, ranging from soft tissue repair to posterior bone block techniques to restore or increase the articular surface. Bone block procedures are indicated in cases of recurrent posterior instability after the failure of conservative treatment or soft tissue techniques, as well as symptomatic demonstrable nonintentional instability, presence of a posterior glenoid defect >10%, increased glenoid retroversion between 10 and 25°, and posterior rim dysplasia. Bone block fixation techniques that avoid screws and metal allow for satisfactory initial clinical results in a safe and reproducible way. An algorithm for the approach and treatment of recurrent posterior glenohumeral instability is presented, as well as the author's preferred surgical technique for arthroscopic posterior bone block.

中文翻译：

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肩后部不稳的综合管理：关节镜下骨块增强的诊断、适应症和技术。

复发性盂肱后部不稳定是一个需要高度临床怀疑和详细研究以找到正确方法和治疗的实体。它的分类必须考虑其生物力学，无论是由于功能性肌肉失衡还是由于结构变化、意志和意图。由于其不同的临床表现和不同的结构改变，从囊盂唇病变和骨缺损到关节盂发育不良和后倾，历史上可用的不同治疗方案的失败率很高。必须使用 CT 和 MRI 进行详细的放射影像学评估，准确评估关节盂和肱骨缺损以及关节盂形态。以肩周肌再训练和外旋肌强化为重点的物理疗法始终是治疗的第一线。当保守治疗失败时，手术治疗必须以存在的结构性病变为指导，从软组织修复到后骨块技术以恢复或增加关节面。骨块手术适用于保守治疗或软组织技术失败后复发性后部不稳定的情况，以及有症状的可证明的非故意不稳定，存在 > 10% 的后部关节盂缺损，关节盂后倾增加 10 至 25°，以及后缘发育不良。避免使用螺钉和金属的骨块固定技术可以安全且可重复的方式获得令人满意的初始临床结果。