The carpal bones in Poland syndrome

Abstract

Objective: Classical Poland syndrome is represented by unilateral aplasia of the sternocostal head of the pectoralis major muscle and ipsilateral simple syndactyly and brachydactyly. Various classifications of the severity of hand involvement have been proposed. Since its initial description, numerous studies have been made of the bony, soft tissue, organ, and hematological disturbances. However, carpal bone involvement has been largely overlooked. The purpose of this study was to evaluate the carpal bones in patients with Poland syndrome from a local (Manitoba) cohort as well as those from the literature.

Materials and methods: Hand radiographs from local patients and cases identified from the literature with confirmed Poland syndrome were examined for evidence of carpal bone involvement. Only cases with radiographs of adequate quality were included in the analysis. Clinical information (including gender and age) was necessary for evaluation of bone maturation. In total, seven local patients and 23 patients from the literature were evaluated. Ethics approval for study of the local patients was obtained by the Research Ethics Board of the University of Manitoba.

Results: Of the 23 literature patients, 12 patients (52%) had abnormal findings. Of the abnormal patients, four of 12 (33%) had carpal fusions, eight of 12 (67%) showed disharmonious ossification between the carpal and tubular bones and seven of 12 (58%) showed delay of carpal ossification. Of the local cohort, three patients were too young to characterize carpal involvement. Of the four remaining patients, two (50%) had abnormal carpal morphology, three out of four had disharmonious ossification and all four had delay of ossification of carpal bones. Carpal fusions, particularly of the scaphoid and trapezium, were common in both groups.

Conclusion: Carpal bone anomalies (delay, disharmony, and/or fusions) are frequent in Poland syndrome and can occur in patients with either mild or severe hand involvement. Imaging of the unaffected hand is helpful in determining the extent of carpal findings.