Obturator externus pyomyositis.

Pyomyositis of the obturator externus muscle is a rare cause of limp and hip pain in children. The exact etiology of the condition remains poorly understood, although a mechanism of transient bacteremia in association with increased muscle susceptibility has been proposed. This case describes the course of a rather than 1 child from presentation to diagnosis and demonstrates the requirement for magnetic resonance imaging in establishing a diagnosis.

Head-at-risk signs in Legg-Calvé-Perthes disease: poor inter- and intra-observer reliability.

Background: The head-at-risk signs are used as prognostic indicators in Legg-Calvé-Perthes disease. These signs have been assessed only once regarding inter-observer reliability, however. Intra-observer reliability seems not to have been studied to date.

The reliability and validity of assessment of sagittal plane deviations in children who have spastic diplegia.

Objective: To assess the reliability and validity of a newly described classification of sagittal plane alignment in spastic diplegic gait.

Design: Twenty split-screen videos of children with spastic diplegia, Gross Motor Function Classification System levels I to III, were viewed on 2 occasions, 6 weeks apart, by 5 raters. The sagittal plane alignments of the right and left lower limbs in gait were classified separately as true equinus, jump knee, apparent equinus, or crouch, based on the published classification.