Work

Age-dependent prevalence of the Notch of Harty (pseudolesion of the tibial plafond) in children, adolescents, and young adults

Year: 2025

Type: article

Abstract: OBJECTIVES: The notch of Harty (NOH) is a pseudolesion located at the distal tibial plafond that can mimic a clinically significant osteochondral lesion. Reported prevalence in an adult population ranged between 25% and 45%, but the prevalence in younger age groups is unknown. In this study, we assessed the age-dependent prevalence of the NOH in a young population to investigate potential remodeling over time. MATERIALS AND METHODS: A retrospective analysis of a single-center database included 895 ankle MRIs of patients aged 6-25 years between 2018 and 2022. Cases with significant artifacts or pathological conditions were excluded. The NOH was categorized into types 1 (fluid-filled) and 2 (cartilage-filled), and measurements were taken for mediolateral, craniocaudal, and anteroposterior dimensions. Logistic and linear regression models with restricted cubic splines assessed age-related trends. Radiographic sensitivity for NOH detection was evaluated in 252 radiographs with MRI-confirmed NOH as a secondary endpoint. RESULTS: The overall prevalence of NOH in this study population was 47.1% (14.9% type 1 and 31.6% type 2). Type 1 prevalence peaked at age 8 and declined into adulthood, while type 2 prevalence peaked at age 14 and stabilized through adolescence. The NOH size increased with age until 16 years and subsequently decreased. Radiographic sensitivity for detecting NOH was 51.2%. CONCLUSION: The NOH is more common in younger individuals, with prevalence and size decreasing with age. This supports its classification as a developmental variant characterized by age-related remodeling. CRITICAL RELEVANCE STATEMENT: This study provides novel insights into the age-dependent prevalence and remodeling of the NOH, enhancing diagnostic precision and improving differentiation between developmental variants and pathological findings in clinical radiology. KEY POINTS: The study investigates the age-dependent prevalence of the NOH. Results show developmental remodeling patterns with prevalence peaking in younger individuals. Data support the theory of NOH being a developmental variant.

Source: Insights into Imaging

DOI: 10.1186/s13244-025-02126-y