小儿拇指扳机指超声表现的初步研究

Ultrasonographic assessment of pediatric trigger thumb:a preliminary study

目的探讨小儿拇指扳机指的超声声像图表现。方法对71例临床诊断为拇指扳机指的患儿行超声检查,观察A1滑车的增厚水平;根据患儿年龄分为3组,分别测量并比较各组患儿患侧与正常侧拇指掌指关节水平及大鱼际中点水平拇长屈肌肌腱的截面积。结果 71例拇指扳机指患儿中双侧发病10例,右侧发病32例,左侧发病29例。所有患儿患侧拇指扳机指均于掌指关节处的A1滑车呈低回声。3个年龄组患儿患侧掌指关节处拇长屈肌肌腱截面积分别为(8.0±1.9)mm2、(9.3±2.2)mm2及(10.2±2.3)mm2,正常侧掌指关节处拇长屈肌肌腱截面积分别为(4.4±1.1)mm2,(4.8±1.4)mm2及(6.2±1.7)mm2,两组比较差异有统计学意义(P<0.01),而3个年龄组患儿患侧及正常侧拇长屈肌肌腱截面积在大鱼际中点水平比较,差异无统计学意义(P>0.05)。结论小儿拇指扳机指超声声像图主要表现为患侧拇长屈肌肌腱在掌指关节处明显增粗,伴有A1滑车增厚。

Objective To investigate the ultrasonographic features of pediatric trigger thumb. Methods Ultrasound was performed in 71 consecutive children with trigger thumb and the ultrasound findings were analyzed as A1 pulley thickening and flexor pollicis longus tefidon thickness. The cross-sectional areas of the flexor tendon at the level of metacarpophalangeal joint and the midline part of the greater thenar were measured among the groups with different ages. Results Of 71 children with trigger thumb, the involved side was right in 32 patients, left in 29 and bilateral in 10. The thickening of A1 pulley was found in all affected sides. The cross-sectional areas of the affected flexor tendon at the level of metacarpophalangeal joint were 8.0 ± 1.9 mm2 ,9.3 ± 2.2 mm2 and 10.2 ±2.3 mm2 respectively among different age groups, which was significantly larger than normal side （4.4 ± 1.1 mm2 ,4.8±1.4 mm2 and 6.2 ± 1.7 mm2, respectively , P 〈 0.01 ） . While no significant differences were found between the flexor tendon cross-sectional areas at the midline part of the greater thenar of the affected and the normal side（P 〉 0.05）. Conclusion The major ultrasonographic changes of pediatric trigger thumb are the thickening of flexor pollicis longus tendon at the level of metacarpophalangeal joint and the thickening of A1 pulley.