Lunate Fracture Morphology in Kienbock's Disease-A Computed Tomography Study

Area of Science:

• Orthopedics
• Radiology
• Biomechanics

Background:

• Kienböck's disease pathogenesis remains unclear, with coronal fractures recognized as a poor prognostic indicator.
• Previous research has identified various fracture types within the lunate bone in Kienböck's disease.

Purpose of the Study:

• To investigate the fracture morphology of the lunate bone in a patient cohort using computed tomography (CT).
• To analyze the relationship between different fracture types and other relevant parameters in Kienböck's disease.

Main Methods:

• Acquisition of patient images using a standardized four-dimensional computed tomography (4D-CT) protocol.
• Review of static and dynamic CT images by two orthopedic surgeons and a consultant radiologist.
• Creation of a fracture map and statistical analysis of fracture type prevalence and relationships.

Main Results:

• Twenty-three patients (11 males, 12 females; mean age 43 years) were analyzed.
• The most frequent fracture lines were coronal (26), proximal subchondral bone plate (24), and avulsion (19).
• Statistically significant differences were observed in the prevalence of proximal vs. distal subchondral bone plate fractures and coronal vs. distal subchondral bone plate fractures. Radiolunate ligament-avulsion fractures were significantly more common than other types.

Conclusions:

• Fracture morphology in Kienböck's disease provides insights into disease pathogenesis.
• Identified fracture lines may correlate with mechanical loading points and ligament avulsions.
• Understanding these fracture types is crucial for predicting disease progression and planning lunate salvage surgery.