METHODS: Online database--Medline, CINAHL and MANTIS--and library searches for the time frame of 1970-2005 were done using the term "leg-length inequality".
RESULTS AND DISCUSSION: Using data on leg-length inequality obtained by accurate and reliable x-ray methods, the prevalence of anatomic inequality was found to be 90%, the mean magnitude of anatomic inequality was 5.2 mm (SD 4.1). The evidence suggests that, for most people, anatomic leg-length inequality does not appear to be clinically significant until the magnitude reaches approximately 20 mm (approximately 3/4").
CONCLUSION: Anatomic leg-length inequality is near universal, but the average magnitude is small and not likely to be clinically significant.
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