Simultaneous feedforward recruitment of the vasti in untrained postural tasks can be restored by physical therapy.
OBJECTIVE
Physical therapy rehabilitation strategies are commonly directed at the alteration of muscle recruitment in functional movements. The aim of this study was to investigate whether feedforward strategies of the vasti in people with patellofemoral pain syndrome can be changed by a physical therapy treatment program in a randomised, double blind, placebo controlled trial.


METHODS
Forty (25 female, 15 male) subjects aged 40 yrs or less (27.2+/-7.8 yrs).


METHODS
Subjects were allocated to either a placebo treatment or a physical therapy intervention program. The postural challenge used as the outcome measure was not included in the training program. Electromyography (EMG) onsets of vastus medialis obliquus (VMO), vastus lateralis (VL), tibialis anterior and soleus were assessed before and after the six week standardised treatment programs.


RESULTS
At baseline the EMG onset of VL occurred prior to that of VMO in both subject groups. Following physical therapy intervention there was a significant change in the time of onset of EMG of VMO compared to VL with the onsets occurring simultaneously. This change was associated with a reduction in symptoms. In contrast, following placebo intervention the EMG onset of VL still occurred prior to that of VMO.


CONCLUSIONS
The results indicate that the feedforward strategy used by the central nervous system to control the patella can be restored. Importantly, the data suggest that this intervention produced a change that was transferred to a task that was not specifically included in the training program. Furthermore, the change in motor control was associated with clinical improvement in symptoms.
Cowan
Sallie M
SM
Centre for Sports Medicine Research and Education, School of Physiotherapy, The University of Melbourne, 200 Berkeley Street, Carlton 3052, Australia. s.cowan@unimelb.edu.au
Bennell
Kim L
KL
Hodges
Paul W
PW
Crossley
Kay M
KM
McConnell
Jenny
J
D000328:Adult; D004185:Disability Evaluation; D004311:Double-Blind Method; D004576:Electromyography; D005260:Female; D005269:Femur; D006801:Humans; D007593:Joint Instability / Q000503:physiopathology / Q000534:rehabilitation* / Q000628:therapy; D007719:Knee Joint / Q000503:physiopathology*; D008297:Male; D018482:Muscle, Skeletal / Q000502:physiology; D010146:Pain / Q000503:physiopathology / Q000534:rehabilitation*; D059408:Pain Management; D010329:Patella; D026741:Physical Therapy Modalities / Q000379:methods*; D011187:Posture / Q000502:physiology*