PDF(Pubmed)
Abstract：
UNASSIGNED: The treatment of bony glenoid defects after anteroinferior shoulder dislocation currently depends on the amount of glenoid bone loss (GBL). Recent studies have described the glenoid concavity as an essential factor for glenohumeral stability. The role of glenoid concavity in the presence of soft tissue and muscle forces is still unknown.
UNASSIGNED: Glenoid concavity would have a major impact on glenohumeral stability in an active-assisted biomechanical model including soft tissue and the rotator cuff\'s compression forces.
UNASSIGNED: Controlled laboratory study.
UNASSIGNED: In 8 human shoulder specimens, individual coordinate systems were calculated based on anatomic landmarks. The glenoid concavity was measured biomechanically and based on computed tomography. Static load was applied to the rotator cuff tendons and the deltoid muscle. In a robotic test setup, anteriorly directed force was applied to the humeral head until translation of 5 mm (Nant) was achieved. Nant was used as a parameter indicating shoulder stability. This was performed in the following testing stages: (1) intact joint, (2) labral lesion, (3) 10% GBL, and (4) 20% GBL. The 8 specimens were divided equally into 2 subgroups (low concavity [LC] versus high concavity [HC]), with 4 specimens each, according to the previously measured concavity.
UNASSIGNED: Anterior glenohumeral stability was highly correlated with the native glenoid concavity (R 2 = 0.8). In the testing stages 1 to 3, we found a significantly higher mean stability in the HC subgroup compared with the LC subgroup (P≤ .0142). The HC subgroup still showed higher absolute Nant values with 20% GBL; however, there was no significant difference from the LC subgroup. The loss of stability in 20% GBL was correlated with the initial concavity (R 2 = 0.86). Thus, a higher loss of Nant in the HC subgroup was observed (P = .0049).
UNASSIGNED: In an active-assisted model with intact soft tissue surrounding and muscular compression forces, the glenoid concavity correlates with shoulder stability. In bony defects, loss of concavity is an essential factor causing instability. Due to their significantly higher native stability, glenoids with HC can tolerate a higher amount of GBL.
UNASSIGNED: Glenoid concavity should be considered in an individualized treatment of bony glenoid defects. Further studies are required to establish reference values and develop therapeutic algorithms.
UNASSIGNED: Glenoid concavity would have a major impact on glenohumeral stability in an active-assisted biomechanical model including soft tissue and the rotator cuff\'s compression forces.
UNASSIGNED: Controlled laboratory study.
UNASSIGNED: In 8 human shoulder specimens, individual coordinate systems were calculated based on anatomic landmarks. The glenoid concavity was measured biomechanically and based on computed tomography. Static load was applied to the rotator cuff tendons and the deltoid muscle. In a robotic test setup, anteriorly directed force was applied to the humeral head until translation of 5 mm (Nant) was achieved. Nant was used as a parameter indicating shoulder stability. This was performed in the following testing stages: (1) intact joint, (2) labral lesion, (3) 10% GBL, and (4) 20% GBL. The 8 specimens were divided equally into 2 subgroups (low concavity [LC] versus high concavity [HC]), with 4 specimens each, according to the previously measured concavity.
UNASSIGNED: Anterior glenohumeral stability was highly correlated with the native glenoid concavity (R 2 = 0.8). In the testing stages 1 to 3, we found a significantly higher mean stability in the HC subgroup compared with the LC subgroup (P≤ .0142). The HC subgroup still showed higher absolute Nant values with 20% GBL; however, there was no significant difference from the LC subgroup. The loss of stability in 20% GBL was correlated with the initial concavity (R 2 = 0.86). Thus, a higher loss of Nant in the HC subgroup was observed (P = .0049).
UNASSIGNED: In an active-assisted model with intact soft tissue surrounding and muscular compression forces, the glenoid concavity correlates with shoulder stability. In bony defects, loss of concavity is an essential factor causing instability. Due to their significantly higher native stability, glenoids with HC can tolerate a higher amount of GBL.
UNASSIGNED: Glenoid concavity should be considered in an individualized treatment of bony glenoid defects. Further studies are required to establish reference values and develop therapeutic algorithms.
摘要：
■肩关节前下脱位后骨性关节窝缺损的治疗目前取决于关节窝骨丢失（GBL）的量。最近的研究将关节盂凹度描述为肱骨稳定性的重要因素。关节盂凹陷在软组织和肌肉力量存在下的作用仍然未知。
■在包括软组织和肩袖压缩力在内的主动辅助生物力学模型中，关节盂的凹陷会对肱骨稳定性产生重大影响。
■对照实验室研究。
■在8个人类肩部标本中，基于解剖界标计算各个坐标系。通过生物力学并基于计算机断层扫描来测量关节盂凹度。向肩袖肌腱和三角肌施加静态载荷。在机器人测试设置中，向肱骨头施加向前的力，直到实现5mm的平移（Nant）。Nant用作指示肩部稳定性的参数。这是在以下测试阶段进行的：（1）完整的关节，(2)唇上病变,(3)10%GBL,和(4)20%GBL。将8个标本平均分为2个亚组（低凹[LC]对高凹[HC]），每个有4个样本，根据先前测量的凹度。
■肱骨前稳定性与天然关节盂凹度高度相关（R2=0.8）。在测试阶段1至3中，我们发现HC亚组的平均稳定性明显高于LC亚组（P≤.0142）。HC亚组仍显示较高的绝对Nant值与20%GBL;然而,与LC亚组无显著差异。20％GBL中稳定性的损失与初始凹度相关（R2=0.86）。因此，在HC亚组中观察到更高的Nant损失(P=.0049)。
■在具有完整软组织周围和肌肉压缩力的主动辅助模型中，关节盂凹度与肩关节的稳定性有关。在骨骼缺陷中，凹度的损失是造成不稳定的一个重要因素。由于其显着更高的天然稳定性，具有HC的类腺样体可以耐受较高量的GBL。
■骨性关节盂缺损的个体化治疗应考虑关节盂凹陷。需要进一步的研究来建立参考值并开发治疗算法。
■在包括软组织和肩袖压缩力在内的主动辅助生物力学模型中，关节盂的凹陷会对肱骨稳定性产生重大影响。
■对照实验室研究。
■在8个人类肩部标本中，基于解剖界标计算各个坐标系。通过生物力学并基于计算机断层扫描来测量关节盂凹度。向肩袖肌腱和三角肌施加静态载荷。在机器人测试设置中，向肱骨头施加向前的力，直到实现5mm的平移（Nant）。Nant用作指示肩部稳定性的参数。这是在以下测试阶段进行的：（1）完整的关节，(2)唇上病变,(3)10%GBL,和(4)20%GBL。将8个标本平均分为2个亚组（低凹[LC]对高凹[HC]），每个有4个样本，根据先前测量的凹度。
■肱骨前稳定性与天然关节盂凹度高度相关（R2=0.8）。在测试阶段1至3中，我们发现HC亚组的平均稳定性明显高于LC亚组（P≤.0142）。HC亚组仍显示较高的绝对Nant值与20%GBL;然而,与LC亚组无显著差异。20％GBL中稳定性的损失与初始凹度相关（R2=0.86）。因此，在HC亚组中观察到更高的Nant损失(P=.0049)。
■在具有完整软组织周围和肌肉压缩力的主动辅助模型中，关节盂凹度与肩关节的稳定性有关。在骨骼缺陷中，凹度的损失是造成不稳定的一个重要因素。由于其显着更高的天然稳定性，具有HC的类腺样体可以耐受较高量的GBL。
■骨性关节盂缺损的个体化治疗应考虑关节盂凹陷。需要进一步的研究来建立参考值并开发治疗算法。
