Lunate morphology

Last revised by Mohamed Saber on 2 Mar 2021

Several classification systems exist for the lunate morphology 1, 2.


The lunate classification proposed by Viegas et al. is arguably the most relevant 3

  • type I lunate: single distal articular facet for the capitate
  • type II lunate: additional distal articular facet medially for the hamate

There is roughly an even prevalence of the two morphology types.

Related pathology

Type I lunates are associated with a higher prevalence of dorsal intercalated segment instability (DISI) deformity in the setting of scaphoid fracture non-union (~75% vs 20%).

Type II lunates are associated with hamatolunate impingement syndrome leading to a higher prevalence of hamatolunate degenerative arthritis 4.

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