AO Research Institute Davos, Clavadelerstrasse 8, 7270, Davos, Switzerland.
Department of Trauma, University Hospital Zurich, Raemistrasse 100, 8091, Zurich, Switzerland.
J Orthop Surg Res. 2023 Jun 2;18(1):401. doi: 10.1186/s13018-023-03879-2.
The incidence of acetabular fractures (AFs) is increasing in all industrial nations, with posterior column fractures (PCFs) accounting for 18.5-22% of these cases. Treating displaced AFs in elderly patients is a known challenge. The optimal surgical strategy implementing open reduction and internal fixation (ORIF), total hip arthroplasty (THA), or percutaneous screw fixation (SF), remains debated. Additionally, with either of these treatment methods, the post-surgical weight bearing protocols are also ambiguous. The aim of this biomechanical study was to evaluate construct stiffness and failure load following a PCF fixation with either standard plate osteosynthesis, SF, or using a screwable cup for THA under full weight bearing conditions.
Twelve composite osteoporotic pelvises were used. A PCF according to the Letournel Classification was created in 24 hemi-pelvis constructs stratified into three groups (n = 8) as follows: (i) posterior column fracture with plate fixation (PCPF); (ii) posterior column fracture with SF (PCSF); (iii) posterior column fracture with screwable cup fixation (PCSC). All specimens were biomechanically tested under progressively increasing cyclic loading until failure, with monitoring of the interfragmentary movements via motion tracking.
Initial construct stiffness (N/mm) was 154.8 ± 68.3 for PCPF, 107.3 ± 41.0 for PCSF, and 133.3 ± 27.5 for PCSC, with no significant differences among the groups, p = 0.173. Cycles to failure and failure load were 7822 ± 2281 and 982.2 ± 428.1 N for PCPF, 3662 ± 1664 and 566.2 ± 366.4 N for PCSF, and 5989 ± 3440 and 798.9 ± 544.0 N for PCSC, being significantly higher for PCPF versus PCSF, p = 0.012.
Standard ORIF of PCF with either plate osteosynthesis or using a screwable cup for THA demonstrated encouraging results for application of a post-surgical treatment concept with a full weight bearing approach. Further biomechanical cadaveric studies with larger sample size should be initiated for a better understanding of AF treatment with full weight bearing and its potential as a concept for PCF fixation.
在所有工业国家，髋臼骨折（AFs）的发病率都在增加，其中后柱骨折（PCFs）占这些病例的 18.5-22%。治疗老年患者移位的 AFs 是一个已知的挑战。实施切开复位内固定（ORIF）、全髋关节置换术（THA）或经皮螺钉固定（SF）治疗的最佳手术策略仍存在争议。此外，对于这些治疗方法中的任何一种，术后负重方案也不明确。本生物力学研究的目的是评估在后柱骨折固定中使用标准钢板内固定、SF 或使用可旋入式杯进行 THA 在完全负重条件下的结构刚度和失效载荷。
使用 12 个复合骨质疏松骨盆。根据 Letournel 分类创建了一个后柱骨折，分为 24 个半骨盆结构，分为三组（n=8）：（i）后柱骨折钢板固定（PCPF）；（ii）后柱骨折 SF（PCSF）；（iii）后柱骨折可旋入式杯固定（PCSC）。所有标本均在逐渐增加的循环载荷下进行生物力学测试，直至失效，并通过运动跟踪监测骨折间的运动。
初始结构刚度（N/mm）为 PCPF 组 154.8±68.3，PCSF 组 107.3±41.0，PCSC 组 133.3±27.5，组间无显著差异，p=0.173。失效循环和失效载荷分别为 PCPF 组 7822±2281 和 982.2±428.1 N，PCSF 组 3662±1664 和 566.2±366.4 N，PCSC 组 5989±3440 和 798.9±544.0 N，PCPF 组显著高于 PCSF 组，p=0.012。
PCF 的标准 ORIF 无论是用钢板内固定还是用可旋入式杯进行 THA，都为应用术后治疗概念提供了令人鼓舞的结果，该概念采用完全负重方法。应进一步开展更大样本量的生物力学尸体研究，以更好地了解完全负重的 AF 治疗及其作为 PCF 固定概念的潜力。
