Nakamura K, Beppu M, Patterson R M, Hanson C A, Hume P J, Viegas S F
Division of Hand Surgery, Department of Orthopaedic Surgery and Rehabilitation, The University of Texas Medical Branch, Galveston, TX 77555-1350, USA.
J Hand Surg Am. 2000 Sep;25(5):877-88. doi: 10.1053/jhsu.2000.9411.
The motions of 2 different types of lunate (type I, no medial hamate facet; type II, medial hamate facet) were evaluated and compared during radial-ulnar deviation of the wrist using radiography and magnetic resonance imaging. Ten right wrists (5 type I and 5 type II lunates) were studied using posteroanterior and lateral x-rays. Six of the 10 normal volunteers (3 type I and 3 type II lunates) were studied using magnetic resonance imaging in 6 positions of radial-ulnar deviation. In the radiographic study the ulnar shift ratio of the lunate (USR), the shortest distance between the proximal ulnar tip of the lunate and the distal ulnar edge of the sigmoid notch of the radius (R-L), the closest distance between the distal ulnar tip of the lunate and the proximal pole of the hamate (L-H), the radius of curvature of the proximal head of the capitate (Cr) on posteroanterior view, and the radiolunate angle on lateral view were measured in each wrist in each of the 6 positions. There were statistically significant differences between type I and II lunates with regard to average maximum ulnar deviation of USR and R-L, total change of USR, R-L distance and L-H distance, average L-H distance and Cr distance in all positions, and average radiolunate angle in neutral and 15 degrees ulnar deviation. In the magnetic resonance imaging study the wrists with a type I lunate did not have contact between the lunate and hamate in any position; the wrists with a type II lunate did have contact between the hamate and the lunate, but only in ulnar deviation. The results of this study demonstrate that the kinematics of a type I lunate are different from those of a type II lunate during radial-ulnar deviation of the wrist.
在手腕进行桡尺偏斜时，使用X线摄影和磁共振成像对两种不同类型的月骨（I型，无内侧钩骨小关节面；II型，有内侧钩骨小关节面）的运动进行了评估和比较。使用正位和侧位X线片对10只右手腕（5只I型月骨和5只II型月骨）进行了研究。在10名正常志愿者中，有6名（3名I型月骨和3名II型月骨）在桡尺偏斜的6个位置进行了磁共振成像研究。在X线摄影研究中，测量了每个手腕在6个位置中的月骨尺侧移位率（USR）、月骨近端尺侧尖端与桡骨乙状切迹远端尺侧边缘之间的最短距离（R-L）、月骨远端尺侧尖端与钩骨近端之间的最近距离（L-H）、正位片上头状骨近端头部的曲率半径（Cr）以及侧位片上的桡月角。I型和II型月骨在USR和R-L的平均最大尺侧偏斜、USR、R-L距离和L-H距离的总变化、所有位置的平均L-H距离和Cr距离以及中立位和尺侧偏斜15度时的平均桡月角方面存在统计学显著差异。在磁共振成像研究中，I型月骨的手腕在任何位置月骨与钩骨之间均无接触；II型月骨的手腕月骨与钩骨之间有接触，但仅在尺侧偏斜时出现。本研究结果表明，在手腕桡尺偏斜过程中，I型月骨的运动学与II型月骨不同。
