title: Randomized controlled trial of Protonics on patellar pain, position, and function.
abstract: OBJECTIVE
  Patellofemoral pain (PFP) and abnormal patellofemoral congruence (PFC) are common athletic problems whose treatment remains controversial. This study examined the effects of a high volume of submaximal knee muscle exercise on objective measures of PFP and PFC under a test-retest design.
  
  
  METHODS
  A sample of 100 subjects was randomly divided into two groups: control and treatment. All subjects of both groups were tested for PFC, using a Merchant x-ray view, function, via Kujala patellofemoral score (KPS), and pain, through a visual analog scale (VAS), initially and then 4 wk later. The treatment group exercised during activities of daily living (ADL) by wearing a Protonics device; the control group did not receive treatment.
  
  
  RESULTS
  One-way analysis of variance tests found no difference between pre- and posttest results for the control group but found significant changes in PFC, KPS, and VAS (all P < 0.001). PFC and joint function improved, and PFP decreased in all subjects of the treatment group.
  
  
  CONCLUSIONS
  It was concluded that the treatment reduced PFP and PFC as compared with the control. A high volume of submaximal knee exercise seems useful for clinical patients with PFP and abnormal PFC.
authors.affiliation: St. Luke's Healthcare Association, St. Luke's Hospital OSF, Saginaw, MI 48602-5375, USA. ketimm1@juno.com
authors.forename: K E
authors.initials: KE
authors.lastname: Timm
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D001696:Biomechanical Phenomena; D001915:Braces; D005081:Exercise Therapy; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000534:rehabilitation*; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000517:prevention & control*; D010329:Patella / Q000503:physiopathology*; D011187:Posture