Pokhvashchev Dmitry, Knox Riley, Herring Matthew, Herfat Safa, Tibrin Marmor Meir
University of California, San Francisco, USA.
Eur J Orthop Surg Traumatol. 2023 Jan;33(1):67-72. doi: 10.1007/s00590-021-03147-1. Epub 2021 Nov 5.
Augmentation strategies for surgical fixation of proximal humerus fractures (PHF) are available to address their relatively high failure rate. The purpose of this study was to compare two medial-buttress augmentation strategies for PHF fixation.
A two-part PHF model with loss of medial buttress was created in 16 synthetic bones. The PHFs were fixed with locking plates and either calcium phosphate cement (CPC) or fibula strut (FS) augmentation. After cadaveric validations, the fixation constructs were subjected to nondestructive axial compression tests, followed by a cyclic test. Construct stiffness and angular displacement of the humerus head were recorded.
Humeral head angular displacement was statistically greater in the CPC group than in the FS group at the applied force of 300 N and higher (p < 0.05). Axial stiffness was statistically greater in the FS fixation group than in the CPC group at initial and final phases of cyclic loading protocol (p < 0.05).
In an osteoporotic cadaveric model of a 2-part PHF with loss of a medial buttress, locked plate constructs augmented with FS have a higher resistance to varus collapse compared to those augmented with CPC.
近端肱骨骨折（PHF）手术固定的增强策略可用于解决其相对较高的失败率。本研究的目的是比较两种用于PHF固定的内侧支撑增强策略。
在16块合成骨中创建了一个内侧支撑缺失的两部分PHF模型。PHF用锁定钢板固定，并采用磷酸钙骨水泥（CPC）或腓骨支撑（FS）增强。在尸体验证后，对固定结构进行无损轴向压缩试验，然后进行循环试验。记录肱骨头部的结构刚度和角位移。
在300 N及更高的作用力下，CPC组的肱骨头角位移在统计学上大于FS组（p < 0.05）。在循环加载方案的初始和最终阶段，FS固定组的轴向刚度在统计学上大于CPC组（p < 0.05）。
在一个两部分PHF且内侧支撑缺失的骨质疏松尸体模型中，与采用CPC增强的锁定钢板结构相比，采用FS增强的锁定钢板结构对内翻塌陷具有更高的抵抗力。
