Lower extremity manifestations of phenylketonuria

Phenylketonuria is an inborn error of metabolism with its most notable characteristic being that of mental retardation. The literature describing this disorder has been reviewed to identify the abnormal lower extremity findings in affected individuals. The dermatologic, osteologic, and neuromuscular systems were all found to be involved. Lower extremity physical examinations were then performed on nine phenylketonuric adults. It was determined that several of the reported manifestations of phenylketonuria were similarly evident in these individuals as well as the presence of additional lower extremity pathology not previously documented. However, the conclusion was made that all findings, past and present, were variable and that no consistent manifestation was apparent.