Relationships between age, gender, ulnar variance and triangular fibrocartilage disc on high-resolution MRI in asymptomatic adults' wrist.

Abstract

Background: Incidental triangular fibrocartilage complex (TFCC) abnormal findings could be detected on magnetic resonance imaging (MRI), whether these incidental findings were causes of symptoms can confuse clinicians. The purpose of this study was to demonstrate the MRI features of triangular fibrocartilage (TFC) disc in asymptomatic adults' wrists and explore the association with age, gender and ulnar variance.

Methods: Healthy adult volunteers who reported no ulnar-sided wrist pain were recruited and underwent MRI examinations. The thickness and angle of TFC and ulnar variance were measured on the mid-coronal slice, and coronal morphology and signal characteristics of the TFC disc were assessed. Regression analyses were performed to evaluate the relationships between the MRI features of TFC and age, gender and ulnar variance.

Results: Eighty-four asymptomatic adult volunteers (42 men, 42 women; mean age of men and women, 37 years and 46 years, respectively) were included, with 23 participants having a TFC defect. Ulnar variance was the influencing factor significantly associated with thickness, angle and morphology of TFC (all p < 0.001). The angles and prevalence of a more distally stretched disc were higher in women compared to men. Age was not a statistically significant factor of TFC thickness and angle, but age had a mediating effect [12.43% (p = 0.016)] on the association between ulnar variance and TFC morphology, while the direct effect of ulnar variance accounted for 87.57% (p < 0.001). Additionally, multivariate logistic regression results showed that an increase in age was significantly associated with an increased prevalence of abnormal TFC signal and discontinuity.

Conclusions: Ulnar variance is the most significant factor in determining TFC thickness, angle, and morphology. Age did not affect thickness and angle directly but may influence the relationship between ulnar variance and TFC morphology, and age is associated with an increased prevalence of abnormal signal and discontinuity in the TFC. This study offers a reference for clinicians and a comprehensive consideration and analysis, including age, ulnar variance, clinical history and physical examination should be made when interpreting MRI findings.