Objective: To evaluate the short-term effectiveness of Kirschner wire (K-wire) elastic fixation in the treatment of Doyle type Ⅰ and Ⅱ mallet finger.
Methods: Between July 2016 and March 2017, 18 patients with Doyle type Ⅰ and Ⅱ mallet finger were treated. There were 12 males and 6 males, with an average age of 45 years (range, 16-61 years). The index finger was involved in 2 cases, the middle finger in 3 cases, the ring finger in 10 cases, and the little finger in 3 cases. The interval from injury to operation ranged from 2 hours to 45 days (median, 5.5 hours). There were 8 patients of closed wound and 10 patients of open wound. Fourteen patients were simply extensor tendon rupture and 4 were extensor tendon rupture complicated with avulsion fracture. The distal interphalangeal joints (DIPJ) of injured fingers were elastically fixed with the K-wire at mild dorsal extend position. The K-wire was removed after 6 weeks, and the functional training started.
Results: The operation time was 34-53 minutes (mean, 38.9 minutes). Patients were followed up 3-8 months (mean, 5 months). All incisions healed primarily and no K-wire loosening or infection happened during the period of fixation. All mallet fingers were corrected. The range of motion (ROM) in terms of active flexion of injured DIPJ was (75.83±11.15)° at 6 weeks after operation, showing significant difference when compared with the normal DIPJ of contralateral finger [(85.28±6.06)°] ( t=3.158, P=0.003). The ROM in terms of active flexion was (82.67±6.78)° in 15 patients who were followed up at 8 months after operation, showing no significant difference when compared with the normal DIPJ of contralateral finger [(86.00±5.73)°] ( t=1.454, P=0.157). After the removal of K-wire at 6 weeks, visual analogue scale (VAS) score of active flexion and of passive flexion to maximum angle were 1.78±0.88 and 3.06±1.06, respectively. According to the total active motion criteria, the effectiveness was rated as excellent in 10 cases, good in 5 cases, moderate in 2 cases, and poor in 1 case, and the excellent and good rate was 83.33%. The patients' satisfaction were accessed by Likert scale, which were 3-5 (mean, 4.2).
Conclusion: K-wire elastic fixation in the treatment of Doyle typeⅠand Ⅱ mallet finger can repair the extensor effectively, correct the mallet finger deformity, and also be benefit for the flexion-extension function restoration of DIPJ.
目的: 探讨克氏针弹性固定治疗 DoyleⅠ、Ⅱ型锤状指的近期疗效。.
方法: 2016 年 7 月—2017 年 3 月，收治 DoyleⅠ、Ⅱ型锤状指 18 例。男 12 例，女 6 例；年龄 16～61 岁，平均 45 岁。损伤指别：示指 2 例，中指 3 例，环指 10 例，小指 3 例。受伤至手术时间 2 h～45 d，中位时间 5.5 h。闭合性损伤 8 例，开放性损伤 10 例。单纯指伸肌腱断裂 14 例，伴撕脱性骨折的伸肌腱止点断裂 4 例。采用克氏针弹性跨关节固定远节指间关节（distal interphalangeal joints，DIPJ）于过伸位，6 周后去除克氏针并进行功能锻炼。.
结果: 手术时间 34～53 min，平均 38.9 min。患者均获随访，随访时间 3～8 个月，平均 5 个月。术后切口均Ⅰ期愈合；患指固定期间未发生克氏针松动、针眼处感染。患者锤状指畸形均得到纠正，术后 6 周拔除克氏针后，DIPJ 被动活动无明显受限，主动屈曲角度为（75.83±11.15）°，与健侧对应指（85.28±6.06）° 比较，差异有统计学意义（ t=3.158， P=0.003）。术后 8 个月，15 例获随访患者患指 DIPJ 主动屈曲角度为（82.67±6.78）°，与健侧对应指（86.00±5.73）° 比较，差异无统计学意义（ t=1.454， P=0.157）。术后 6 周拔除克氏针后，DIPJ 主动屈曲时疼痛视觉模拟评分（VAS）为（1.78±0.88）分，被动屈曲至最大关节活动度时 VAS 评分为（3.06±1.06）分。术后 3 个月，根据总主动活动度（TAM）评定标准，获优 10 例、良 5 例、中 2 例、差 1 例，优良率为 83.33%；患者满意度 Likert 评分为 3～5 分，平均 4.2 分。.
结论: 克氏针弹性固定治疗 DoyleⅠ、Ⅱ型锤状指，能有效修复指伸肌腱，纠正锤状指畸形，利于远期 DIPJ 屈伸功能恢复。.
Keywords: Kirschner wire; Mallet finger; elastic fixation; extensor tendon; range of motion of joint.