You will be given a definition of a task first, then some input of the task.
Given an abstract, generate a keyword (a noun phrase) that best describes the focus or contribution of the paper. Such keywords can be directly from the given abstract or outside it.

Abstract: Limping is never normal, and few parents tolerate the problem long before seeking medical consultation. However, the conditions that may produce a limp are legion and run the gamut from a stone in the shoe to the first manifestation of malignant neoplasm or chronic renal disease. As a consequence, one must have an orderly approach to diagnosis. Many of the problems that cause the child to limp are presented, but this article is concerned with an overview of the problem, differential diagnosis, and suggested steps in evaluating the child who limps.
Output:
Child