Prevalence of types of intercondylar notch shape on anterior cruciate ligament-injured patients

Abstract

Introduction: The anterior cruciate ligament (ACL) is the most injured knee ligament, with intercondylar notch shape as a key risk factor. Narrower, A-shaped notches, common in females, increase injury risk. This study evaluates the prevalence of notch types and their links to demographic and anthropometric factors in ACL injuries.

Method: This retrospective study was conducted at Pokhara Academy of Health Sciences, among adults aged 18 years and above with arthroscopically confirmed ACL injuries between July 2023 and July 2025. Preoperative MRI scans were analyzed to classify intercondylar notch morphology into three types: A, U, and W based on axial T2-weighted images. BMI was calculated and categorized using WHO Asian cutoffs, and associations between notch type and demographic or anthropometric variables were analyzed, with p < 0.05 set as the threshold for statistical significance.

Result: A total of 45 patients with ACL injury were included, with a median age of 33 years (IQR: 25–43) and an age range of 20–60 years. The majority, 31(68.9%), were aged 20–39 years, and 27 (60%) were male, while 18(40%) were female. The most common intercondylar notch type was Type U in 28 (62.2%) patients, followed by Type A in 16 (35.6%) and Type W in 1 (2.2%). A statistically significant association was found between gender and notch type, and between age group and notch morphology. However, no significant association was observed between BMI category and notch type.

Conclusion: Type U notch was the most common among ACL-injured patients, with notch morphology significantly associated with gender and age but not with BMI.