Poland–Mebius syndrome: A clinical case and review of the literature

BACKGROUND: Currently, the eponym “Poland syndrome” has become a universal term for clinicians for all pectoral muscle developmental disorders with symbrachydactyly and without. Misinterpretation of the diagnosis in patients with pectoral muscle underdevelopment can narrow the diagnostic search, making it difficult to genetically verify the diagnosis. Thus, this study was conducted. CLINICAL CASE: We present the results of our clinical observation of a 17-year-old adolescent with complaints of restricted movement in the joints of the right hand, right shoulder joint, shortening of the right upper extremity, and chest wall deformity. Orthopedic examination and computed tomography indicated the presence of Poland syndrome, severe Sprengel’s deformity (soft tissue form), severe left-sided keel chest deformity, kyphoscoliosis of the thoracic spine, and Scheiermann–Mau disease. The focal neurological symptoms and associated structural and functional changes in the medulla oblongata were characteristic of the extended Mebius syndrome. DISCUSSION: Modern hypotheses of pathogenesis, clinical features, and possibilities of diagnostics of this syndrome are considered. CONCLUSIONS: The variety of clinical manifestations of the Poland–Mebius syndrome and the current lack of clear genetic markers for both the Mebius syndrome and Poland syndrome hindered the establishment of a consensus among researchers, that is, whether the Poland–Mebius syndrome is an independent disease or a group of individual phenotypic features that are components of previously known syndromes. Further molecular genetic studies may provide a basis for the designation of Poland–Mebius syndrome as a separate entity.