远指间关节过伸角度固定对锤状指疗效的影响

The effect of DIP joint hyperextension angle on the treatment outcomes of mallet fingers

目的分析远指间关节过伸角度固定对锤状指疗效的影响。方法2008至2010年收治伸肌终腱止点近端1～3mm断裂致锤状指34例，随机分成两组。A组克氏针固定远指间关节于0°位，B组克氏针固定远指间关节于过伸5°-15°位；两组均不固定近指间关节，常规缝合肌腱断端。术后6周取出克氏针，经3～6个月功能锻炼后，测量患指远指间关节屈伸角度及活动范围，并进行统计学分析。结果术后两组患者远指间关节屈、伸角度及活动范围比较差异均无统计学意义。B组6例患者延迟拆线3～5d，9例伤口皮缘表现轻度血运障碍，其中2例出现小范围浅表坏死结痂，1例肌腱再次断裂。结论锤状指手术时固定远指间关节过伸角度应该以健侧对应手指或相邻手指作为对照，尽量接近中立位，过伸角度不超过5°。

Objective To investigate the influence of the angle of DIP joint hyperextension fixation on the treatment outcomes of mallet finger management. Methods From 2008 to 2010, 34 eases of extensor tendon rapture 1 to 3 mm proximal to the tendon insertion were treated. These patients were randomly divided into two groups. DIP joints of the patients in group A were immobilized at 0 degree by Kirschner wires, while DIP joints of the patients in group B were pinned at 5 to 15 degrees of hyperextension. The ruptured extensor tendon was sutured. K-wires were removed after 6 weeks. Range of motion of the DIP joint was measured after 3 to 6 months rehabilitation. Statistic analysis was done to compare measurements from two groups. Results Range of motion of the DIP joint, flexion angle and extension angle were not statistically different between tile two groups （ P 〉 0.05）. In group B, delay in suture removal for 3 to 5 days was necessary in 6 patients. Mild circulation compromise at the edge of the wound occurred in 9 cases in group B, which led to superficial skin necrosis in 2 cases. Tendon re-rupture occurred in 1 case also in this group. Conclusion It is necessary to take the contralateral finger or neighboring finger as reference to determine the angle of DIP joint immobilization. DIP joint should be immobilized at neutral angle or no more than 5 degrees of hyperextension.