title: Biomechanical Profiles When Towing a Sled and Wearing a Weighted Vest Once Cleared for Sports Post-ACL Reconstruction.
abstract: BACKGROUND
  Though rehabilitation attempts to correct "stiff knee gait" and control for dynamic limb valgus after anterior cruciate ligament reconstruction (ACLR), impaired biomechanics often persist when an individual is cleared to return to sport (RTS). Reduced knee extension moments (KEMs) and knee flexion angles (KFAs) often continue. While at the hip, increased hip adduction angles (HADDAs) and hip internal rotation angles (HIRAs) often persist in spite of dynamic hip stabilization exercises. Sled towing and weighted vest tasks increase KEM and hip extension moments (HEMs) in healthy individuals, yet biomechanical profiles during these tasks after ACLR are unknown.
  
  
  OBJECTIVE
  Weighted gait will increase KEM, HEM, hip abduction moments (HABDMs), and hip external rotation moments (HERMs) and will not increase unwanted biomechanics (limb asymmetries, HIRA, HADDA) compared with normal gait.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  Level 4.
  
  
  METHODS
  Fourteen men and 24 women who were 5 to 12 months after ACLR, had no concomitant ligament injuries, and were cleared to RTS were recruited. Sexes were evaluated independently given the sex-specific incidence to ACL injury, reinjury, and gait responses to certain interventions. Joint moment impulses and peak angles over the first 25% of stance were compared between limbs and across tasks (eg, unweighted gait, sled 50% body weight [BW], and vest 50% BW).
  
  
  RESULTS
  Men showed that weighted gait increased KEM, HEM, HERM, HADBM (vest only), HADDA, HIRA (sled only), and KFA. Asymmetrical KEM and KFA existed across tasks. Women showed that weighted gait increased KEM, HEM, HERM, HADBM (vest only), HFA (sled only), HADDA, and KFA. Asymmetrical KEM, HEM, HIRA, and KFA (sled only) existed across tasks.
  
  
  CONCLUSIONS
  Weighted gait generally increased joint moments. Unwanted biomechanics were unique for each weighted gait task.
  
  
  CONCLUSIONS
  Though joint moments increased, both tasks created unwanted biomechanics after ACLR. Persistent hip (women only) and KEM asymmetries across tasks when cleared to RTS are concerning given the relationship among these biomechanics and decreased functional performance.
authors.affiliation: Department of Physical Therapy, University of New England, Portland, Maine ehartigan@une.edu.
authors.forename: Erin
authors.initials: E
authors.lastname: Hartigan
authors.affiliation: Department of Physical Therapy, University of New England, Portland, Maine.
authors.forename: Michael
authors.initials: M
authors.lastname: Lawrence
authors.affiliation: OA Centers for Orthopaedics, A Division of Spectrum Medical Group, Portland, Maine.
authors.forename: Thomas
authors.initials: T
authors.lastname: Murray
authors.affiliation: OA Centers for Orthopaedics, A Division of Spectrum Medical Group, Portland, Maine.
authors.forename: Bernadette
authors.initials: B
authors.lastname: Shaw
authors.affiliation: ProActive Physical Therapy, Lacey, Washington.
authors.forename: Erin
authors.initials: E
authors.lastname: Collins
authors.affiliation: Mercy Hospital, Portland, Maine.
authors.forename: Kaitlin
authors.initials: K
authors.lastname: Powers
authors.affiliation: University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.
authors.forename: James
authors.initials: J
authors.lastname: Townsend
mesh_terms: D000293:Adolescent; D000328:Adult; D000070598:Anterior Cruciate Ligament Injuries / Q000534:rehabilitation / Q000601:surgery*; D059549:Anterior Cruciate Ligament Reconstruction / Q000534:rehabilitation*; D001265:Athletic Injuries / Q000534:rehabilitation / Q000601:surgery*; D001696:Biomechanical Phenomena; D005081:Exercise Therapy / Q000379:methods*; D005260:Female; D005684:Gait / Q000502:physiology*; D006615:Hip / Q000502:physiology; D006801:Humans; D007717:Knee / Q000502:physiology; D008297:Male; D008875:Middle Aged; D009068:Movement; D000068958:Return to Sport; D012399:Rotation; D055815:Young Adult
keywords: gait mechanics; rehabilitation; return to sport