Xie Chen, Dong Yanchen, Yao Zhaozhe, Li Zongyu
Department of hand surgery, The 960th Hospital of PLA, No.25 Shifan Road, Tianqiao District, Jinan, Shandong, China.
Department of outpatient, The 960th Hospital of PLA, No.25 Shifan Road, Tianqiao District, Jinan, Shandong, China.
J Orthop Surg Res. 2025 Apr 15;20(1):376. doi: 10.1186/s13018-025-05795-z.
Metacarpal neck fractures are common and there are numerous surgical methods available, but each has certain disadvantages and limitations. We modified the conventional Ilizarov external mini-fixator and this study is designed to compare the biomechanical stability of a modified Ilizarov external mini-fixator with conventional fixation methods for metacarpal neck fractures and to provide a basis for its clinical application.
Forty fresh porcine metacarpal specimens were used to create metacarpal neck fracture models. The specimens were randomly assigned to four fixation groups (n = 10) as follows: (1) modified Ilizarov external mini-fixator (IEF), (2) retrograde crossed Kirschner wires (KW), (3) antegrade intramedullary Kirschner wires (IK), and (4) locking plate fixation (LP). In the IEF group, the modified design involved crossing two Kirschner wires (K-wires) through the fracture line, with their tails bent twice and connected to the external fixator frame. Biomechanical testing was performed using a modified three-point bending test. Maximum fracture force and bending stiffness were calculated from the force-displacement curves. Kruskal-Wallis test was used to compare statistical differences in maximum fracture force and stiffness among the groups, followed by post hoc pairwise comparisons adjusted with Bonferroni corrections.
The median maximum fracture force values (± interquartile range, IQR) for each group were as follows: IEF 160.3 ± 55.6 N, LP 173.5 ± 42.6 N, KW 91.1 ± 23.1 N, and IK 79.8 ± 37.8 N. The corresponding stiffness values were as follows: IEF 29.5 ± 10.4 N/mm, LP 32.9 ± 10.4 N/mm, KW 17.2 ± 11.3 N/mm, and IK 18.2 ± 13.7 N/mm. The IEF group demonstrated significantly higher maximum fracture force and stiffness than the KW and IK groups; however, no statistically significant differences were observed in the IEF group compared with the LP group.
The modified Ilizarov external mini-fixator provided significantly greater biomechanical stability for metacarpal neck fractures than retrograde crossed K-wires and antegrade intramedullary K-wires, achieving comparable performance to the locking plate system. This modified design combines the simplicity and minimally invasive advantages of K-wire fixation with enhanced stability, potentially facilitating early joint mobilization and minimizing the risk of complication.
掌骨颈骨折很常见，有多种手术方法可供选择，但每种方法都有一定的缺点和局限性。我们对传统的伊里扎洛夫微型外固定架进行了改良，本研究旨在比较改良的伊里扎洛夫微型外固定架与掌骨颈骨折传统固定方法的生物力学稳定性，并为其临床应用提供依据。
使用40个新鲜猪掌骨标本制作掌骨颈骨折模型。将标本随机分为四个固定组（n = 10），如下：（1）改良伊里扎洛夫微型外固定架（IEF），（2）逆行交叉克氏针（KW），（3）顺行髓内克氏针（IK），（4）锁定钢板固定（LP）。在IEF组中，改良设计包括将两根克氏针穿过骨折线，其尾部弯曲两次并连接到外固定架框架。使用改良的三点弯曲试验进行生物力学测试。根据力-位移曲线计算最大骨折力和弯曲刚度。采用Kruskal-Wallis检验比较各组最大骨折力和刚度的统计学差异，随后进行经Bonferroni校正的事后两两比较。
每组的最大骨折力中位数（±四分位间距，IQR）如下：IEF组为160.3±55.6 N，LP组为173.5±42.6 N，KW组为91.1±23.1 N，IK组为79.8±37.8 N。相应的刚度值如下：IEF组为29.5±10.4 N/mm，LP组为32.9±10.4 N/mm，KW组为17.2±11.3 N/mm，IK组为18.2±13.7 N/mm。IEF组的最大骨折力和刚度显著高于KW组和IK组；然而，IEF组与LP组相比未观察到统计学显著差异。
改良的伊里扎洛夫微型外固定架为掌骨颈骨折提供了比逆行交叉克氏针和顺行髓内克氏针显著更高的生物力学稳定性，其性能与锁定钢板系统相当。这种改良设计结合了克氏针固定的简单性和微创优势以及增强的稳定性，可能有助于早期关节活动并将并发症风险降至最低。
