Department of Orthopedic Surgery, University of Texas Health Science Center at Houston, Bellaire, Texas.
J Arthroplasty. 2023 Jul;38(7S):S292-S297. doi: 10.1016/j.arth.2023.03.008. Epub 2023 Mar 16.
Due to increasing volume of total hip arthroplasties, periprosthetic femoral fractures have become a common complication with increased revision burden and perioperative morbidity. The objective of this study was to evaluate the fixation stability of Vancouver B2 fractures treated with 2 techniques.
A common B2 fracture was created by reviewing 30 type B2 cases. The fracture was then reproduced in 7 pairs of cadaveric femora. The specimens were divided into 2 groups. In Group I ("reduce-first"), the fragments were reduced first, followed by implantation of a tapered fluted stem. In Group II ("ream-first"), the stem was implanted in the distal femur first, followed by fragment reduction and fixation. Each specimen was loaded in a multiaxial testing frame with 70% of peak load during walking. A motion capture system was used to track the motion of the stem and fragments.
The average stem diameter in Group II was 16.1 ± 0.4 mm, versus 15.4 ± 0.5 mm in Group I. The fixation stability was not significantly different in the 2 groups. After the testing, the average stem subsidence was 0.36 ± 0.31 mm and 0.19 ± 0.14 mm (P = .17) and the average rotation was 1.67 ± 1.30° and 0.91 ± 1.11° (P = .16) in Groups I and II, respectively. Compared to the stem, there was less motion of the fragments and there was no difference between the 2 groups (P > .05).
When tapered fluted stems were used in combination with cerclage cables for treatment of Vancouver type B2 periprosthetic femoral fractures, both the "reduce-first" and "ream-first" techniques showed adequate stem and fracture stability.
随着全髋关节置换术数量的增加，假体周围股骨骨折已成为一种常见并发症，增加了翻修负担和围手术期发病率。本研究旨在评估两种技术治疗温哥华 B2 型骨折的固定稳定性。
通过回顾 30 例 B2 型病例，创建了一个常见的 B2 型骨折。然后在 7 对尸体股骨中复制了该骨折。标本分为两组。在 I 组（“先复位”）中，先复位骨折块，然后植入锥形开槽髓内钉。在 II 组（“先扩髓”）中，先在股骨远端植入髓内钉，然后复位和固定骨折块。每个标本在一个多轴测试框架中以步行时 70%的峰值负荷加载。运动捕捉系统用于跟踪髓内钉和骨折块的运动。
II 组的平均髓内钉直径为 16.1 ± 0.4mm，而 I 组为 15.4 ± 0.5mm。两组的固定稳定性无显著差异。测试后，I 组和 II 组的平均髓内钉下沉分别为 0.36 ± 0.31mm 和 0.19 ± 0.14mm（P =.17），平均旋转分别为 1.67 ± 1.30°和 0.91 ± 1.11°（P =.16）。与髓内钉相比，骨折块的运动较小，两组之间无差异（P >.05）。
当锥形开槽髓内钉与环扎线联合用于治疗温哥华 B2 型假体周围股骨骨折时，“先复位”和“先扩髓”技术均显示出足够的髓内钉和骨折稳定性。
