A Comparative Study of the Effect of Visual Input and Standing Position on Postural ‎Control in People with and without Patellofemoral Pain Syndrome

In order to evaluate postural control in people with musculoskeletal disorders, examining different standing positions provides useful information to researchers. On the other hands, visual manipulation also plays an important role in the analysis of postural control of people with patellofemoral pain syndrome in static and challenging conditions. The purpose of this research is to investigate the effect of vision manipulation and standing position on postural control in people with patellofemoral pain syndrome and control group.

30 participants with patellofemoral pain syndrome (aged 23.50 ± 3.76 years, height 167.5±8.58 cm, weight 63.86±12.05 kg) and 30 healthy control (aged 22.43 ± 2.84 years, height 166.25±9.7 cm, weight 59.36±9.35 kg) participated in the Quasi-experimental study in Ghaem Hospital of Mashhad in 2017. The postural sway measures (area, anterior-posterior displacement, medial-lateral displacement, and mean velocity) were recorded with force plate while standing (single-and double leg) in participants with and without patellofemoral pain syndrome. Also, two groups were examined in terms of manipulating visual inputs (eyes open or closed).

Interference of vision by standing position by group in all postural sway measures were statistically significant (p˂0.04). The removal of visual inputs led to a significant increase (p˂0.05) in the postural sway measures during single leg stance in participants with and without patellofemoral pain syndrome (p˂0.05).

It seems that the participants with and without patellofemoral pain syndrome use different central strategies for postural control.  The lack of visual input led to different response in terms of increasing postural sway in patients with patellofemoral pain syndrome as compared to healthy control.