Linear arrangement of bony outgrowths of the distal phalanges of the foot in relation to ligamentous structures: a radiological analysis.

BACKGROUND: Long-term observation of patients with complaints involving the distal phalanx of the hallux (disturbances of nail plate growth, periungual fold changes, and abnormal alignment of the distal phalanx relative to the proximal phalanx) has drawn attention to recurrent bony changes on its lateral aspects. These observations provided part of the rationale for earlier anatomical studies, which confirmed the presence of the collateral ligaments of the distal phalanges of the foot macroscopically and histologically. Such bony changes have previously been classified as exostoses, osteophytes, or nonspecific bony outgrowths. The study aimed to assess, by retrospective radiological analysis, the morphology of bony outgrowths on the lateral aspects of the distal phalanx of the hallux and their possible relationship to the topography of the ligamentous structures described previously.

MATERIALS AND METHODS: The material comprised radiographs of the toes from 54 patients aged 29-65 years who were examined in routine clinical practice. The qualitative analysis assessed the location, shape, direction of growth, spatial relationships, and continuity of the lesions.

RESULTS: The bony outgrowths on the lateral aspects of the distal phalanx of the hallux were neither random nor scattered but formed an ordered, linear arrangement that may correspond to the topography of the ligamentous structures.

CONCLUSIONS: This pattern suggests a link with chronic overload of the ligamentous attachments and a possible enthesopathic nature. The findings indicate that this mechanism should be considered in the differential diagnosis and radiological classification of these bony changes.