An Alternative Method for the Measurement of Pelvic Skeletal Asymmetry (PSA) Using an Asymmetry Ratio (AR)

Abstract

This paper presents an alternative method for determining PSA. Frequently, physical therapists rely heavily on visual palpatory techniques for the assessment of pelvic skeletal asymmetry; however, a more objective approach using valid and reliable measurement systems is needed. This study shows how a relatively simple and non-invasive measurement system will provide accurate measurements of PSA. The asymmetry ratio, which is easily derived from these measurements, provides a quantitative measurement and a differentiation between two common types of PSA, leg length discrepancy (LLD) and iliac rotation asymmetry (IRA). A distinct advantage is that the AR provides normalized data that take into account the individual differences in pelvic width. Alternative measurement systems may also be used to estimate AR provided they give reliable measurements of the height and width differences of the pelvic bony landmarks.

Keywords:

• PELVIC SKETETAL ASYMMETRY
• LEG LENGTH DISCREPANCY
• ILIAC ROTATION ASYMMETRY