拇掌指关节背侧半脱位的X线表现

目的: 探讨拇掌指关节背侧半脱位的X线表现.材料和方法: 7例拇掌指关节背侧半脱位的X线表现进行回顾性分析.并与随机抽取30例正常拇指正侧位X线片对照.结果: 30例正常拇掌指关节X线表现包括: (1)拇指指间关节曲屈≤18°;(2)无拇指背伸;(3)籽骨指侧缘位于掌骨头腕侧1.0～3.2mm或相同水平;(4)拇掌指关节间隙均匀.拇掌指关节背侧半脱位的X线表现包括: (1)拇指指间关节曲屈;(2)拇指近节指骨背伸;(3)籽骨位置异常;(4)拇掌指关节间隙不均匀.结论: 标准拇掌指关节正侧位片对诊断拇掌指关节背侧半脱位非常重要,熟悉其正常X线表现是正确诊断拇掌指关节背侧半脱位的关键.

The X-ray Features of Metacropophalangeal Joint Dorsal Subluxation of the Thumb

Purpose: To explore the X-ray Features of metacropophalangeal joint dorsal Subluxation of the thumb. Materials and Methods: The X-ray appearances of 7 cases with metacropophalangeal joint dorsal Subluxation of the thumb with X-ray were analysed retrospectively comparing with 30 cases of the normal radiograph of the thumb. Results: The X-ray appearances of normal radiograph of the thumb included: (1) The flexional angel of interphalangeal joints of thumb was less than 18 degrees . (2) Proximal phalanges of thumb wasn't dorsal extension. (3)Sesamoid bone of thumb was located wrist, distance from 1.0mm to 3.2mm or same level .(4) The clearance of metacrpophalangeal joint of thumb was equal . The X-ray appearances of metacropophalangeal joint dorsal Subluxation of the thumb included: (1) Proximal phalanges of thumb was dorsal extension.(2) Interphalangeal joints of thumb was flexion.(3)Sesamoid bone of thumb was malposition.(4) The clearance of metacrpophalangeal joint of thumb was asymmetry. Conclusion : The standard lateral and anterior-posterior view of metacropophalangeal joint of the thumb is very important,and reconizing its normal X-ray features is the key for correct diagnosing a metacropophalangeal joint dorsal subluxation of the thumb.