Arthroscopic lunate morphology and wrist disorders

Area of Science:

• Orthopedic surgery
• Hand and wrist anatomy
• Radiology

Background:

• The lunate bone, a key carpal bone, has two main morphological types: single (Type 1) and double (Type 2) distal facets.
• The clinical significance of these lunate types regarding wrist disease and trauma incidence is not well-established.
• Understanding this association may improve diagnosis and treatment strategies for various wrist conditions.

Purpose of the Study:

• To investigate the potential association between lunate morphology (Viegas classification) and the occurrence of specific wrist disorders.
• To determine if certain lunate types are more prevalent in conditions like Kienböck's disease, ulnar wrist pain, fractures, dislocations, or degenerative wrist diseases.

Main Methods:

• Retrospective review of 637 patients undergoing wrist arthroscopy for wrist disorders.
• Classification of lunate morphology into Type 1 (single facet) and Type 2 (two facets) based on arthroscopic images using the Viegas classification.
• Categorization of wrist disorders into four groups: fractures/dislocations, Kienböck's disease, ulnar wrist pain, and degenerative disease.

Main Results:

• A Viegas Type 1 lunate was present in 349 wrists, and Type 2 in 288 wrists.
• The incidence of Type 2 lunates varied significantly across the different wrist disorder groups.
• Notably, Type 2 lunates were found significantly less frequently in patients with Kienböck's disease and ulnar wrist pain compared to trauma and degenerative groups.

Conclusions:

• Lunate morphology exhibits variable incidence across different wrist disorders.
• A lower proportion of Type 2 lunates is associated with Kienböck's disease and ulnar wrist pain.
• These findings suggest that lunate morphology may be a contributing factor or indicator for specific wrist pathologies.