Poland Syndrome
Incidence
Occurrence is usually sporadic. Poland syndrome is estimated to have an incidence of 1 per 32,000 live births. A few familial cases have been reported. They do not show a uniform mendelian pattern. Familial aggregation of "incomplete" cases has been observed as well. Poland Syndrome affects males more commonly than females. Pedigrees compatible with autosomal dominant inheritance have been reported. All features are unilateral. Occurs on right side in 75% of cases. Three times more common in males. Majority of cases are sporadic.
Clinical Characteristics
Poland Syndrome is a rare condition that is evident at birth (congenital). Associated features may be extremely variable from case to case. However, it is classically characterized by absence (aplasia) of chest wall muscles on one side of the body (unilateral) and abnormally short, webbed fingers (symbrachydactyly) of the hand on the same side (ipsilateral). In those with the condition, there is typically unilateral absence of the pectoralis minor and the sternal or breastbone portion of the pectoralis major. The pectoralis minor is a thin, triangular muscle of the upper chest wall; the pectoralis major is a large, fanlike muscle that covers most of the upper, front part of the chest. Affected individuals may have variable associated features, such as underdevelopment or absence of one nipple (including the darkened area around the nipple [areola]) and/or patchy absence of hair under the arm (axilla). In females, there may be underdevelopment or absence (aplasia) of one breast and underlying (subcutaneous) tissues. In some cases, associated skeletal abnormalities may also be present, such as underdevelopment or absence of upper ribs; elevation of the shoulder blade (Sprengel deformity); and/or shortening of the arm, with underdevelopment of the forearm bones (i.e., ulna and radius). Poland Syndrome affects males more commonly than females and most frequently involves the right side of the body. The exact cause of the condition is unknown. Poland syndrome is characterized by hypoplasia or absence of breast or nipple, hypoplasia of subcutaneous tissue, absence of the costosternal portion of the pectoralis major muscle, absence of the pectoralis minor muscle, and absence of costal cartilages or ribs 2, 3, and 4 or 3, 4, and 5. Clinical manifestations of Poland syndrome are extremely variable and not all features are found in one individual. Classically, the sequence also includes ipsilateral hand anomalies. Identified patients may be screened for renal and other anomalies. Occurrence is usually sporadic. Poland syndrome is estimated to have an incidence of 1 per 32,000 live births. A few familial cases have been reported. They do not show a uniform mendelian pattern. Familial aggregation of "incomplete" cases has been observed as well. Poland syndrome may be associated with a wide range of other defects such as Moebius anomaly, Goldenhar anomaly, primary microcephaly, a lower extremity counterpart of Poland syndrome, a pedunculated finger-like tag on the leg or severe deficiency of limbs. Poland sequence could have either a vascular disruptive origin or it could be under the control of a paradominant gene. The condition results in physical and cosmetic disabilities which can be treated if properly triaged. The chest wall anatomy may be delineated with computed tomography and MRI if surgery is planned.
Precipitants
None
Provocation Tests
None
Diagnostic Procedures
It is a clinical diagnosis.