summary Beckwith-Wiedemann Syndrome is a congenital condition caused by a mutation in chromosome 11p15.5 that presents with hemihypertrophy, macroglossia, abdominal wall defects, and hypoglycemia. Diagnosis is made using physical examination and genetic testing. Treatment involves a multidisciplinary approach to address orthopedic manifestations, abdominal abnormalities, and overgrowth. Epidemiology Incidence 1 in 13,700 births Demographics 1:1 male to female Etiology An overgrowth syndrome characterized by spectrum of clinical manisfestations, highlighted by: major criteria: overgrowth abdominal wall defects, incl. omphalocele macroglossia or large tongue minor criteria hemihypertrophy (10-20%) ear anomalies neonatal hypoglycemia nephromegaly Pathophysiology pancreatic islet cell hypertrophy causes repeated bouts of infantile hypoglycemia resulting in spasticity Genetics inheritance sporadic in 85% of cases autosomal dominant with incomplete penetrance in remaining 15% mutation chromosome 11p15.5 Associated conditions orthopaedic manifestations hemihypertrophy medical conditions patients have a predisposition for embryonal tumors, i.e. Wilm's tumor, and should be screened with US every 3-6 months until 5-8 years of age Presentation Physical exam macroglossia midface hypoplasia infraorbital creases anterior linear ear lobe creases visceromegaly hemihypertrophy Imaging Radiographs recommended views comparison view of affected limb with contralateral limb Treatment Operative epiphysiodesis indications growth arrest of the affected limb