The Association Between Lunate Morphology and Scaphoid Fractures: A Comparative Radiographic Assessment.

PURPOSE: This study compared lunate morphology on wrist radiographs from patients with scaphoid fractures with those from a control group without scaphoid fractures.

METHODS

Patients with scaphoid fractures diagnosed between 2015 and 2023 were reviewed retrospectively. Wrist radiographs were assessed to determine lunate morphology, capitate-triquetrum distance, and scaphoid fracture location. The lunate morphology was assessed according to both the midcarpal (Viegas classification) and radiocarpal (Antuña-Zapico classification) joints. The results were compared with 200 control wrist radiographs without scaphoid fractures.

RESULTS

The distribution of lunate morphology according to the Viegas classification revealed type II lunates in 64% (212/331) of scaphoid fractures compared with 34% (68/200) in controls. In contrast, radiocarpal-based lunate morphology showed no between-group difference. The capitate-triquetrum distance was higher in the scaphoid fracture group than in controls. Within the scaphoid fracture group, no association was observed between lunate morphology, capitate-triquetrum distance, and fracture location.

CONCLUSIONS

Lunates with a medial hamatolunate facet (type II) were more frequent among patients with a scaphoid fracture than in controls, and the capitate-triquetrum distance was also higher in the fracture group. By contrast, radiocarpal-based lunate morphology was not associated with scaphoid fracture.

TYPE OF STUDY/LEVEL OF EVIDENCE: Prevalence IV.