Kim Dohyun, Lim Joon-Ryul, Yoon Tae-Hwan, Shin Seung-Hwan, Chun Yong-Min
Arthroscopy and Joint Research Institute, Department of Orthopedic Surgery, Severance Hospital, Yonsei University College of Medicine, Seoul, Republic of Korea.
J Bone Joint Surg Am. 2024 Oct 2;106(19):1750-1756. doi: 10.2106/JBJS.23.00480. Epub 2024 Aug 23.
Previous studies assessing surgical fixation of osteoporotic proximal humeral fractures have primarily focused on medial calcar support. In this study, we utilized a specific model for 2-part surgical neck fracture of the osteoporotic proximal humerus to investigate how severe comminution of the greater tuberosity (GT) lateral wall affects biomechanical stability after fixation with a plate.
Ten matched pairs of cadaveric humeri (right and left) were assigned to either a surgical neck fracture alone (the SN group) or a surgical neck fracture with GT lateral wall comminution (the LW group) with use of block randomization. We removed 5 mm of the lateral wall of the GT to simulate severe comminution of the lateral wall. Axial compression stiffness, torsional stiffness, varus bending stiffness, and the single load to failure in varus bending were measured for all plate-bone constructs.
Compared with the SN group, the LW group showed a significant decrease in all measures, including torsional stiffness (internal, p = 0.007; external, p = 0.007), axial compression stiffness (p = 0.002), and varus bending stiffness (p = 0.007). In addition, the mean single load to failure in varus bending for the LW group was 62% lower than that for the SN group (p = 0.005).
Severe comminution of the GT lateral wall significantly compromised the biomechanical stability of osteoporotic, comminuted humeral surgical neck fractures.
Although the generalizability of this cadaveric model may be limited to the extreme clinical scenario, the model showed that severe comminution of the GT lateral wall significantly compromised the stability of osteoporotic humeral surgical neck fractures fixed with a plate and screws alone.
以往评估骨质疏松性肱骨近端骨折手术固定的研究主要集中在内侧距支撑。在本研究中，我们利用骨质疏松性肱骨近端两部分手术颈骨折的特定模型，来研究大结节（GT）外侧壁的严重粉碎如何影响钢板固定后的生物力学稳定性。
使用区组随机化将十对匹配的尸体肱骨（左右）分别分配至单纯手术颈骨折组（SN组）或伴有GT外侧壁粉碎的手术颈骨折组（LW组）。我们去除GT外侧壁5mm以模拟外侧壁的严重粉碎。对所有钢板-骨结构测量轴向压缩刚度、扭转刚度、内翻弯曲刚度以及内翻弯曲时的单次破坏载荷。
与SN组相比，LW组在所有测量指标上均显著降低，包括扭转刚度（内侧，p = 0.007；外侧，p = 0.007）、轴向压缩刚度（p = 0.002）和内翻弯曲刚度（p = 0.007）。此外，LW组内翻弯曲时的平均单次破坏载荷比SN组低62%（p = 0.005）。
GT外侧壁的严重粉碎显著损害了骨质疏松性粉碎性肱骨干手术颈骨折的生物力学稳定性。
尽管该尸体模型的普遍性可能仅限于极端临床情况，但该模型表明，GT外侧壁的严重粉碎显著损害了仅用钢板和螺钉固定的骨质疏松性肱骨干手术颈骨折的稳定性。
