第一跖楔关节融合术中骨内固定与跖板固定的比较：一项尸体生物力学分析

Intraosseous fixation compared to plantar plate fixation for first metatarsocuneiform arthrodesis: a cadaveric biomechanical analysis.

作者信息

Roth Klaus Edgar, Peters Jennifer, Schmidtmann Irene, Maus Uwe, Stephan Daniel, Augat Peter

机构信息

Center of Orthopedic and Trauma Surgery, University Medical Center of the Johannes Gutenberg University, Mainz, Germany

Center of Orthopedic and Trauma Surgery, University Medical Center of the Johannes Gutenberg University, Mainz, Germany.

出版信息

Foot Ankle Int. 2014 Nov;35(11):1209-16. doi: 10.1177/1071100714547082. Epub 2014 Aug 13.

DOI:10.1177/1071100714547082

PMID:25121509

Abstract

BACKGROUND

Metatarsocuneiform (MTC) fusion is a treatment option for management of hallux valgus. We compared the biomechanical characteristics of an internal fixation device with plantar plate fixation.

METHODS

Seven matched pairs of feet from human cadavers were used to compare the intramedullary (IM) device plus compression screw to plantar plate combined with a compression screw. Specimen constructs were loaded in a cyclic 4-point bending test. We obtained initial/final stiffness, maximum load, and number of cycles to failure. Bone mineral density was measured with peripheral quantitative computed tomography. Performance was compared using time to event analysis with number of cycles as time variable, and a proportional hazard model including shared frailty model fitted with treatment and bone mineral density as covariates.

RESULTS

On average the plates failed after 7517 cycles and a maximum load of 167 N, while the IM-implants failed on average after 2946 cycles and a maximum load of 69 N. In all pairs the 1 treated with IM-implant failed earlier than the 1 treated with a plate (hazard ratio for IM-implant versus plate was 79.9 (95% confidence interval [6.1, 1052.2], P = .0009). The initial stiffness was 131 N/mm for the plantar plate and 43.3 N/mm for the IM implant. Initial stiffness (r = .955) and final stiffness (r = .952) were strongly related to the number of cycles to failure. Bone mineral density had no effect on the number of cycles to failure.

CONCLUSION

Plantar plate fixation created a stronger and stiffer construct than IM fixation.

CLINICAL RELEVANCE

A stiffer construct can reduce the risk of nonunion and shorten the period of non-weight-bearing.

摘要

背景

跖楔关节（MTC）融合术是治疗拇外翻的一种选择。我们比较了一种内固定装置与跖板固定的生物力学特性。

方法

使用来自人类尸体的7对匹配的足，将髓内（IM）装置加加压螺钉与跖板联合加压螺钉进行比较。标本结构在循环四点弯曲试验中加载。我们获得了初始/最终刚度、最大载荷和失效循环次数。用外周定量计算机断层扫描测量骨密度。使用以循环次数为时间变量的事件时间分析以及包括将治疗和骨密度作为协变量的共享脆弱模型的比例风险模型比较性能。

结果

平均而言，钢板在7517次循环和167 N的最大载荷后失效，而IM植入物平均在2946次循环和69 N的最大载荷后失效。在所有配对中，接受IM植入物治疗的一侧比接受钢板治疗的一侧更早失效（IM植入物与钢板的风险比为79.9（95%置信区间[6.1, 1052.2]，P = .0009）。跖板的初始刚度为131 N/mm，IM植入物为43.3 N/mm。初始刚度（r = .955）和最终刚度（r = .952）与失效循环次数密切相关。骨密度对失效循环次数没有影响。