Laboratory-based measurement of standing balance in individuals with knee osteoarthritis: A systematic review

- Standing postural control is impaired in people with knee osteoarthritis.
- Available literature highlights a lack of consistency in testing methods in this patient group.
- Most commonly reported outcome measure is centre of pressure path length.

BackgroundLaboratory-based measurement of standing balance is used to assess postural control in people with and without pathology, including knee osteoarthritis. However, no summary of available data has been reported in this patient population. This study aimed to summarize available data and testing methods for individuals with knee osteoarthritis.MethodsMedline (OvidSP and PubMed), Embase, CINAHL, and Web of Science were searched from 1994 to October 25, 2014 to identify studies containing a quantifiable measure of standing balance. Methodological quality was assessed using a modified 17-item Downs & Black quality index. Studies scoring < 50% were eliminated.FindingsThe search strategy initially yielded 1523 unique papers; 21 met all inclusion and quality assessment criteria. The variables measured in three or more of the 21 papers were anteroposterior centre of pressure (COP) velocity, mediolateral COP velocity, mean COP velocity, anteroposterior range of COP, mediolateral range of COP, anteroposterior COP standard deviation, mediolateral COP standard deviation, COP path length, COP area, Biodex anteroposterior score, Biodex mediolateral score, and overall Biodex score. In general, people with knee osteoarthritis exhibited worse standing balance compared to healthy controls. However, there remained much discrepancy in testing procedures across studies.InterpretationThese findings indicate that people with knee osteoarthritis exhibit altered postural control. However, no conclusions could be made on the differences between radiographic severities. That said, these findings provide an opportunity for future researchers and clinicians to compare their findings with the currently published data.