Haase Steven C, Berger Richard A, Shin Alexander Y
Department of Surgery, University of Michigan Health System, Ann Arbor, MI, USA.
J Hand Surg Am. 2007 Sep;32(7):1009-12. doi: 10.1016/j.jhsa.2007.06.005.
Type I lunates have a single distal facet for articulation with the capitate; type II lunates have an additional (medial) hamate facet on the distal articular surface. We retrospectively reviewed a series of patients with scaphoid nonunions to determine if there was an association between lunate morphology and the degree of carpal instability observed. Association between lunate morphology and the location of the scaphoid fracture (proximal or waist) was also investigated.
Radiographs were evaluated for 45 patients with established scaphoid nonunions. Lunate morphology, scaphoid fracture location, and radiolunate angle were determined.
Type I lunates were present in 21 patients. Of these, 15 were found to have a dorsal intercalated segment instability pattern (radiolunate angle greater than 15 degrees ). By contrast, only 4 of the patients with type II lunates exhibited this pattern of instability. No significant association was found between lunate morphology and the scaphoid fracture location.
Type II lunate morphology is associated with significantly decreased incidence of dorsal intercalated segment instability (DISI) deformity in cases of established scaphoid nonunion (p = .0002). Lunate morphology, however, was not significantly associated with the location of the scaphoid fracture in these cases (p = .19).
I型月骨有一个单一的远侧关节面与头状骨相关节；II型月骨在远侧关节面上有一个额外的（内侧）钩骨关节面。我们回顾性分析了一系列舟骨不愈合患者，以确定月骨形态与观察到的腕骨不稳定程度之间是否存在关联。还研究了月骨形态与舟骨骨折部位（近端或腰部）之间的关联。
对45例确诊为舟骨不愈合的患者的X线片进行评估。确定月骨形态、舟骨骨折部位和桡月角。
21例患者为I型月骨。其中，15例发现有背侧插入节段不稳定模式（桡月角大于15度）。相比之下，II型月骨患者中只有4例表现出这种不稳定模式。月骨形态与舟骨骨折部位之间未发现显著关联。
在确诊的舟骨不愈合病例中，II型月骨形态与背侧插入节段不稳定（DISI）畸形的发生率显著降低相关（p = .0002）。然而，在这些病例中，月骨形态与舟骨骨折部位无显著关联（p = .19）。
