Background

Knowledge of the proximal edge of the germinal matrix is essential to avoid injuries in the germinal matrix. The previous index such as terminal tendon insertion is not visible from the body surface. The purpose of this study was to examine the relationship between the proximal edge of the germinal matrix and the body surface indexes by ultrasonographic measurements.

Methods

All participants underwent X-rays of the hand and were grouped based on the presence or absence of osteoarthritis in the distal interphalangeal (DIP) joint. The distance from the proximal edge of the germinal matrix to dorsal distal interphalangeal crease (parameter D1), and to ‘‘DIP joint extension boundary line’’ (parameter D2) were measured using ultrasonography.

Results

Thirty middle fingers of 24 patients were enrolled; 13 fingers were in control group and 17 fingers were in Heberden's node group. The average of parameter D1 was 6.17 mm (SD 1.12) in the control group (N = 13), and was 7.04 mm (SD 1.31) in Heberden's node group (N = 17) without significant difference. The DIP joint extension boundary line was not visible in 7 fingers with severe DIP joint osteoarthritis. The average of parameter D2 was 0.00 mm (SD 0.00) in the control group (N = 13), and was 0.04 mm (SD 0.13) in Heberden's node group (N = 10).

Conclusions

We suggest that DIP joint extension boundary line and dorsal distal interphalangeal crease are valuable indexes to predict the proximal edge of the germinal matrix from the body surface. Though the DIP joint extension boundary line was not visible in some cases, once it has been sighted, the line shows where the germinal matrix exactly is.

中文翻译：

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生发基质的新体表指标：DIP关节延伸边界线和背侧远端指间折痕

背景

了解生发基质的近端边缘对于避免生发基质受伤至关重要。从体表看不到诸如末端腱插入之类的先前指标。本研究的目的是通过超声测量检查生发基质近端边缘与体表指数之间的关系。

方法

所有参与者均接受了手部 X 光检查，并根据远端指间关节 (DIP)是否存在骨关节炎进行分组。使用超声检查测量从生发基质的近端边缘到背侧远端指间折痕（参数D1）和到“DIP关节延伸边界线”（参数D2）的距离。

结果

纳入24名患者的30根中指；对照组有13根手指，Heberden结节组有17根手指。对照组（N = 13）参数D1平均值为6.17 mm（SD 1.12），Heberden淋巴结组（N = 17）参数D1平均值为7.04 mm（SD 1.31），无显着差异。7例严重DIP关节骨关节炎的手指，DIP关节延伸界线不可见。对照组（N = 13）参数D2的平均值为0.00 mm（SD 0.00），Heberden淋巴结组（N = 10）为0.04 mm（SD 0.13）。

结论

我们认为DIP关节延伸边界线和背侧远端指间折痕是从体表预测生发基质近端边缘的有价值的指标。尽管在某些情况下 DIP 关节延伸边界线不可见，但一旦看到它，该线就会显示生发基质的确切位置。