Original research| Volume 100, ISSUE 2, P220-229, February 2019

Added Value of Isolated Core Postural Control Training on Knee Pain and Function in Women With Patellofemoral Pain Syndrome: A Randomized Controlled Trial

Published:September 26, 2018DOI:



      To evaluate the added value of isolated core postural control training on knee pain and function in women with patellofemoral pain syndrome (PFPS).


      Randomized controlled trial.


      Rehabilitation sciences research center.


      Women (N=33) between 18 and 30 years of age with PFPS were randomly assigned to a control group (n=16) or the experimental group (n=17).


      Participants in both groups received the same stretching and strengthening exercises during 4 weeks (12 sessions 3 days per week). The experimental group also received isolated core postural training with an unstable seat apparatus.

      Main Outcome Measures

      Center of pressure (CoP) trajectories in sitting postural control, pain intensity, and function were recorded before and after the 4-week intervention period. Functional capacity and pain intensity were reassessed 3 months after the intervention.


      After treatment, both groups had significant improvements in pain, function (P<.001), and CoP trajectories in sitting postural control (control group P<.05, experimental group P<.001). Between-group comparisons demonstrated greater improvements in pain, function, and CoP trajectories in the experimental group (P<.001). This group also had significantly greater improvements in pain and Kujala Anterior Knee Pain Scale score at 3-month follow-up compared to the control group (P<.001).


      Adding isolated core postural control training to physiotherapy exercises was associated with significantly greater improvements in pain, function, and CoP trajectories than physiotherapy exercises alone. Therefore, unstable sitting postural control training is potentially useful to enhance rehabilitation management in patients with PFPS.


      List of abbreviations:

      AKPS (Anterior Knee Pain Scale), CoP (center of pressure), NRS (numeric rating scale), PFPS (patellofemoral pain syndrome), RMS (root mean square)
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