Liu George T, Balldin B Christian, Zide Jacob R, Chen Christopher T
Associate Professor, Department of Orthopaedic Surgery, University of Texas Southwestern Medical Center, Dallas, TX.
Orthopaedic Surgeon, Burkhart Research Institute for Orthopaedics, The San Antonio Orthopaedic Group, San Antonio, TX.
J Foot Ankle Surg. 2017 Jul-Aug;56(4):813-816. doi: 10.1053/j.jfas.2017.04.014.
The flexor hallucis longus tendon transfer is commonly used to restore function in chronic Achilles tendon ruptures and chronic Achilles tendinopathy. The tendon is often secured to the calcaneus either through a bone tunnel or by an interference screw. We hypothesized that tenodesis using the bone tunnel method would be mechanically superior to interference screw fixation for flexor hallucis longus transfers. Eight matched pairs of cadaveric specimens were assigned randomly to the bone tunnel or interference screw technique and were loaded to failure. Biomechanical analysis was performed to evaluate the ultimate strength, peak stress, Young's modulus, failure strain, and strain energy. Unpaired comparison, paired comparison, and linear regression analyses were used to determine statistical significance. A slight 22% ± 9% decrease in Young's modulus and a 52% ± 18% increase of strain energy were found in the interference screw group. However, no differences in ultimate strength, peak stress, or failure strain were seen between the 2 groups on paired comparison. Our findings suggest that interference screw fixation provides similar spontaneous biomechanical properties to the use of a bone tunnel for flexor hallucis longus transfer to the calcaneus. The interference screw is a practical option for fixation of the flexor hallucis longus tendon to the calcaneus and can be performed through a single incision approach.
拇长屈肌腱转位术常用于恢复慢性跟腱断裂和慢性跟腱病的功能。该肌腱通常通过骨隧道或挤压螺钉固定于跟骨。我们假设，对于拇长屈肌腱转位术，采用骨隧道法的腱固定术在力学上优于挤压螺钉固定。将八对匹配的尸体标本随机分配至骨隧道组或挤压螺钉组，并加载至失效。进行生物力学分析以评估极限强度、峰值应力、杨氏模量、失效应变和应变能。采用非配对比较、配对比较和线性回归分析来确定统计学意义。挤压螺钉组的杨氏模量略有下降，为22%±9%，应变能增加了52%±18%。然而，配对比较显示两组之间在极限强度、峰值应力或失效应变方面无差异。我们的研究结果表明，挤压螺钉固定与使用骨隧道将拇长屈肌腱转位至跟骨具有相似的自发生物力学特性。挤压螺钉是将拇长屈肌腱固定于跟骨的一种实用选择，可通过单切口入路完成。
