Hemihypertrophy. Concepts and controversies.

Abstract

Hemihypertrophy is best defined as asymmetry between the right and left sides of the body to a greater degree than can be attributed to normal variation. This asymmetry often appears as a difference in the size or length of the extremities, but it may also involve the head, trunk, and internal organs. It is often extremely difficult to distinguish hemihypertrophy from normal variation. However, this distinction is very important because young children who have hemihypertrophy are at increased risk of malignant intra-abdominal tumors, such as Wilms tumor or hepatoblastoma9,21,22,24,27,29,31,47,60. The increased risk of neoplasia has led to the controversial recommendation of frequent abdominal ultrasound screening designed to detect the tumor at the earliest possible stage2,12,16,25. The orthopaedic literature regarding hemihypertrophy has focused primarily on the treatment of discrepancy between the lengths of the lower limbs and has only superficially acknowledged link between hemihypertrophy and cancer in children4,37,38,45. Even the most recent pediatric and pediatric orthopaedic textbooks mention this association only briefly if at all8,42,59. The objectives of the present review were to describe the clinical features of hemihypertrophy and its related syndromes, to focus on the relationship between hemihypertrophy and malignant tumors in children, and to discuss the controversy surrounding the frequent abdominal ultrasound screening that is recommended for this group of patients. Hemihypertrophy occurs when a limb or one side of the body enlarges asymmetrically compared with the contralateral limb or side beyond the limits of normal variation. This enlargement may affect only the soft tissues, but it ordinarily involves both the soft tissues and the underlying skeleton. Although …