Background

The current study aimed to compare biomechanical stability and healing process of side-to-side repair with overlapping repair after Achilles tendon lengthening with Z-plasty.

Methods

In our study, 22 Sprague Dawley male rats were used. Side-to-side repairs were classified as group 1 and overlapping repairs as group 2. The left and right legs of seven rats were used to compare early group 1 and early group 2 biomechanical test results at day 0. Seven rats were used to compare late group 1 and late group 2 biomechanical test results at day 28. Both the right and left tendons were tested from the four rats examined in the biomechanically in the untreated control group. The last remaining four rats were used for histopathological evaluation of tendon repair, at 28-days from the index procedure.The ultimate load to failure was compared between groups.

Results

At time 0, there were no measurable differences between group 1 (3.8 ± 1.4 N) and group 2 (3.7 ± 1.1 N), and both could endure less than one-tenth of the untreated control (49 ± 12). At 28 days, ultimate load to failure improved significantly in both group 1 (16.2 ± 3.5 N) and even more in group 2 (36 ± 8.1 N). While there was a significant difference between group 1 and group 2, neither were able to meet the untreated control (49 ± 12). Histopathological evaluation in the post-healing period showed that fibrosis, neovascularization, and inflammation increased in both groups.

Conclusion

The overlapping suture technique and epitenon healing have more stability compared to side-to-side suture technique and endotenon healing. Human population trials may or may not exist, our study suggests it should be considered and further investigation needed before actual clinical application.

中文翻译：

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在 Z 形成形术跟腱延长中，重叠修复和跟腱愈合在生物力学上比左右修复和腱内愈合更稳定

背景

本研究旨在比较 Z 形跟腱延长术后侧对侧修复与重叠修复的生物力学稳定性和愈合过程。

方法

在我们的研究中，使用了 22 只 Sprague Dawley 雄性大鼠。并排修复为第1组，重叠修复为第2组。7只大鼠的左腿和右腿用于比较第0天早期第1组和早期2组的生物力学测试结果。7只大鼠用于比较第 1 组晚期和第 2 组晚期生物力学测试结果在第 28 天。在未处理的对照组中，对四只接受生物力学检查的大鼠的右肌腱和左肌腱进行了测试。最后剩下的四只大鼠在索引程序后 28 天用于肌腱修复的组织病理学评估。比较各组之间的极限负荷至失效。

结果

在时间 0，第 1 组 (3.8 ± 1.4 N) 和第 2 组 (3.7 ± 1.1 N) 之间没有可测量的差异，两者都可以承受不到未处理对照组 (49 ± 12) 的十分之一。在 28 天时，第 1 组 (16.2 ± 3.5 N) 和第 2 组 (36 ± 8.1 N) 的极限失效载荷都有显着改善。虽然第 1 组和第 2 组之间存在显着差异，但均未达到未治疗对照组 (49 ± 12)。愈合后的组织病理学评估显示，两组的纤维化、新生血管形成和炎症均有所增加。

结论

与左右缝合技术和腱鞘愈合相比，重叠缝合技术和腱鞘愈合具有更高的稳定性。人群试验可能存在也可能不存在，我们的研究表明在实际临床应用之前应该考虑并需要进一步调查。