Insertional desmopathy of the nuchal ligament in sport horses remains a poorly characterized orthopaedic phenomenon, with limited and inconsistent terminology in the scientific literature. This study investigated the prevalence, morphology, and localization of nuchal ligament enthesopathies in a cohort of actively competing horses using clinical and radiological assessments. Pathological changes were detected in 91% of evaluated individuals, predominantly as asymptomatic lesions identified during routine imaging. Two principal morphological types were discerned: rounded and coronoid-like bone formations, with comparable distribution among sexes and age groups. Lesion localization most commonly encompassed both the upper and lower regions of the occipital plate but was rarely confined to ligament attachment alone. No correlation was found between lesion size, shape, or location and sex, breed, or age, but horses over 7 years have greater length, depth, sum, and surface area of the new bone formations and more frequently display lesions in both the upper and lower positions than only in the upper. None of the studied horses exhibited related clinical symptoms. The functional relevance of these changes remains to be established, suggesting the necessity for long-term follow-up and further biomechanical investigation to determine potential effects on equine performance.