Objectives: 

To evaluate the effect of a traditional “center-center” end point for distal tibia nailing in comparison with a lateral-of-center end point on fracture malalignment in a cadaver model.

Methods: 

Nine matched pairs of human cadaveric lower-extremity specimens were used to model the effect of nail end point on fracture alignment in extra-articular distal tibia fractures. After simulation of the fracture through a standardized osteotomy, 1 member of each pair was fixed with an intramedullary nail using a “center-center” end point, whereas a lateral-of-center end point was used for the other member of the pair. Specimens were stripped of soft tissue, and digital calipers were used to measure fracture translation and gap medially, laterally, anteriorly, and posteriorly. Coronal plane angulation at each fracture was measured on the final mortise image.

Results: 

The average coronal angulation was 7.0 degrees of valgus (with a SD of 4.1) in central-end point specimens versus 0.2 degrees of valgus (SD = 1.5) in lateral-end point specimens (P < 0.001). Lateral-end point specimens also demonstrated significantly less fracture gap medially (mean 0.2 vs. 3.1 mm for central-end point specimens, P < 0.001), anteriorly (mean 0.1 vs. 1.3 mm, P = 0.003), and posteriorly (mean 0.3 vs. 2.2 mm, P = 0.003). Lateral-end point specimens also showed less lateral translation (mean 0.6 vs. 1.6 mm, P = 0.006).

Conclusions: 

Lateral-of-center nail end points may help surgeons restore native alignment in extra-articular distal tibia fractures and avoid valgus malalignment.

中文翻译：

---

远端胫骨钉中横向端点与中央端点的批判性分析：它会影响对齐吗？

目标： 

评估传统“中心-中心”远端胫骨钉固定端点与中心外侧端点对尸体模型骨折排列不正的影响。

方法： 

使用九对匹配的人类尸体下肢标本来模拟髓内钉端点对关节外远端胫骨骨折中骨折对齐的影响。通过标准化截骨术模拟骨折后，每对中的一名成员使用“中心-中心”端点用髓内钉固定，而另一名成员则使用中心外侧端点。剥去样本的软组织，并使用数字卡尺测量骨折平移和内侧、外侧、前部和后部间隙。在最终的榫眼图像上测量每个骨折处的冠状面角度。

结果： 

中央端点标本的平均冠状角为 7.0 度外翻（SD 为 4.1），而横向端点标本的平均冠状角为 0.2 度外翻（SD = 1.5）（P < 0.001 ）。外侧端点标本还表现出内侧骨折间隙明显较小（中央端点标本平均为 0.2 毫米与 3.1 毫米，P < 0.001）、前部骨折间隙（平均为 0.1 毫米与 1.3 毫米，P = 0.003）和后部骨折间隙（平均为 0.3 毫米）与 2.2 毫米相比，P = 0.003）。横向终点样本也显示出较小的横向平移（平均 0.6 与 1.6 毫米，P = 0.006）。

结论： 

中心外侧钉端点可以帮助外科医生恢复关节外远端胫骨骨折的自然对齐，并避免外翻排列不正。