title: Lower extremity muscle activation onset times during the transition from double-leg stance to single-leg stance in anterior cruciate ligament injured subjects.
abstract: The goal of this study was to evaluate muscle activation onset times (MAOT) of both legs during a transition task from double-leg stance (DLS) to single-leg stance (SLS) in anterior cruciate ligament injured (ACLI) (n=15) and non-injured control subjects (n=15) with eyes open and eyes closed. Significantly delayed MAOT were found in the ACLI group compared to the control group for vastus lateralis, vastus medialis obliquus, hamstrings medial, hamstrings lateral, tibialis anterior, peroneus longus and gastrocnemius in both vision conditions, for gluteus maximus and gluteus medius with eyes open and for tensor fascia latae with eyes closed. Within the ACLI group, delayed MAOT of tibialis anterior with eyes open and gastrocnemius with eyes closed were found in the injured leg compared to the non-injured leg. All other muscles were not significantly different between legs. In conclusion, the ACLI group showed delayed MAOT not only around the knee, but also at the hip and ankle muscles compared to the non-injured control group. No differences between both legs of the ACLI group were found, except for tibialis anterior and gastrocnemius. These findings indirectly support including central nervous system re-education training to target the underlying mechanisms of these altered MAOT after ACL injury.
authors.affiliation: KU Leuven Musculoskeletal Rehabilitation Research Group, Department of Rehabilitation Sciences, Faculty of Kinesiology and Rehabilitation Sciences, Tervuursevest 101 b1501, 3001 Heverlee, Belgium. Electronic address: bart.dingenen@faber.kuleuven.be.
authors.forename: Bart
authors.initials: B
authors.lastname: Dingenen
authors.affiliation: KU Leuven Department of Electrical Engineering, Faculty of Engineering Technology Services, Andreas Vesaliusstraat 13, 3000 Leuven, Belgium; KU Leuven Cardiovascular and Respiratory Rehabilitation Research Group, Department of Rehabilitation Sciences, Faculty of Kinesiology and Rehabilitation Sciences, Tervuursevest 101 b1501, 3001 Heverlee, Belgium. Electronic address: luc.janssens@kuleuven.be.
authors.forename: Luc
authors.initials: L
authors.lastname: Janssens
authors.affiliation: Department of Orthopedics, University Hospitals Leuven, Campus Pellenberg, Leuven, Weligerveld 1, 3212 Pellenberg, Belgium. Electronic address: luyckx.thomas@gmail.com.
authors.forename: Thomas
authors.initials: T
authors.lastname: Luyckx
authors.affiliation: Department of Orthopedics, University Hospitals Leuven, Campus Pellenberg, Leuven, Weligerveld 1, 3212 Pellenberg, Belgium; Department of Orthopedic Surgery, AZ Herentals Hospital, Nederrij 133, 2200 Herentals, Belgium. Electronic address: steven@kreutzfeldverein.be.
authors.forename: Steven
authors.initials: S
authors.lastname: Claes
authors.affiliation: Department of Orthopedics, University Hospitals Leuven, Campus Pellenberg, Leuven, Weligerveld 1, 3212 Pellenberg, Belgium. Electronic address: johan.bellemans@skynet.be.
authors.forename: Johan
authors.initials: J
authors.lastname: Bellemans
authors.affiliation: KU Leuven Musculoskeletal Rehabilitation Research Group, Department of Rehabilitation Sciences, Faculty of Kinesiology and Rehabilitation Sciences, Tervuursevest 101 b1501, 3001 Heverlee, Belgium. Electronic address: filip.staes@faber.kuleuven.be.
authors.forename: Filip F
authors.initials: FF
authors.lastname: Staes
mesh_terms: D000328:Adult; D000843:Ankle Joint / Q000294:innervation / Q000503:physiopathology; D016118:Anterior Cruciate Ligament / Q000503:physiopathology*; D000070598:Anterior Cruciate Ligament Injuries; D002490:Central Nervous System / Q000503:physiopathology; D004576:Electromyography; D005260:Female; D006621:Hip Joint / Q000294:innervation / Q000503:physiopathology; D006801:Humans; D007719:Knee Joint / Q000294:innervation / Q000503:physiopathology; D035002:Lower Extremity / Q000294:innervation / Q000503:physiopathology; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000294:innervation / Q000503:physiopathology; D009469:Neuromuscular Junction / Q000503:physiopathology; D004856:Postural Balance / Q000502:physiology*; D011187:Posture / Q000502:physiology*; D016474:Weight-Bearing / Q000502:physiology*; D055815:Young Adult
keywords: Anterior cruciate ligament injury; Double-leg stance; Lower extremity; Neuromuscular control; Single-leg stance