Isolated pediatric hemihyperplasia requiring surgical debulking of the thigh

•Isolated Hemihyperplasia is a rare form of an overgrowth syndrome.•Pediatric patient had developed a gait-altering mass in the adductor compartment.•We offered surgical debulking as definitive management.•We preserved the neurovascular pedicles of critical muscles.•Patient demonstrated improved form and function post-operatively.

Isolated Hemihyperplasia (IHH) is a rare disorder that results in the enlargement of a portion of a limb, a complete limb or an entire half of an individual's body. We describe an 11 year-old girl with isolated hemihyperplasia of her right upper and lower extremities, breast, and vulvar region. A mass consisting of asymmetric enlargement and fatty infiltration of the right adductor compartment was first noticed at approximately 4 years of life and progressed dramatically to severely affect her gait. We surgically debulked the thigh and resected the excess skin to restore symmetry. The patient did well postoperatively, achieved excellent cosmesis, and restoration of gait.