title: Quadriceps EMG in open and closed kinetic chain tasks in women with patellofemoral pain.
abstract: The authors investigated whether the discrepancy noted in the literature regarding delayed and decreased activity in vastus medialis obliquus (VMO) in people with patellofemoral pain (PFP) depends on the nature of the open kinetic chain (OKC) and the closed kinetic chain (CKC) in the experimental task. They hypothesized that activity in VMO would be more delayed and decreased in CKC tasks than in OKC tasks. Women with PFP (n = 17) and healthy controls (n = 17) performed isometric quadriceps contractions in CKC and OKC tasks. The authors manipulated only the application of resistance. Electromyographs (EMGs) showed that participants with PFP reacted later and activated the quadriceps more in the CKC task but had intramuscular quadriceps coordination similar to that of controls. The nature of the OKC task or the CKC task does not seem to explain contradictory findings regarding VMO activation.
authors.affiliation: Umeå University, Umeå, Sweden. anki.stensdotter@physiother.umu.se
authors.forename: Ann-Katrin
authors.initials: AK
authors.lastname: Stensdotter
authors.forename: Paul
authors.initials: P
authors.lastname: Hodges
authors.forename: Fredrik
authors.initials: F
authors.lastname: Ohberg
authors.forename: Charlotte
authors.initials: C
authors.lastname: Häger-Ross
mesh_terms: D000328:Adult; D001696:Biomechanical Phenomena; D016022:Case-Control Studies; D002908:Chronic Disease; D004576:Electromyography; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D007698:Kinesis; D016555:Matched-Pair Analysis; D009048:Motor Skills / Q000502:physiology*; D046788:Patellofemoral Pain Syndrome / Q000503:physiopathology*; D052097:Quadriceps Muscle / Q000502:physiology* / Q000503:physiopathology; D011930:Reaction Time / Q000502:physiology*; D012016:Reference Values; D018709:Statistics, Nonparametric