title: Tibial rotation under combined in vivo loading after single- and double-bundle anterior cruciate ligament reconstruction.
abstract: OBJECTIVE
  To evaluate in vivo the differences in tibial rotation between single- and double-bundle anterior cruciate ligament (ACL)-reconstructed knees under combined loading conditions.
  
  
  METHODS
  An 8-camera optoelectronic system and a force plate were used to collect kinematic and kinetic data from 14 patients with double-bundle ACL reconstruction, 14 patients with single-bundle reconstruction, 12 ACL-deficient subjects, and 12 healthy control individuals while performing 2 tasks. The first included walking, 60° pivoting, and stair ascending, and the second included stair descending, 60° pivoting, and walking. The 2 variables evaluated were the maximum range of internal-external tibial rotation and the maximum knee rotational moment.
  
  
  RESULTS
  Tibial rotation angles were not significantly different across the 4 groups (P = .331 and P = .851, respectively) or when side-to-side differences were compared within groups (P = .216 and P = .371, respectively) for the ascending and descending maneuvers, nor were rotational moments among the 4 groups (P = .418 and P = .290, respectively). Similarly, for the descending maneuver, the rotational moments were not significantly different between sides (P = .192). However, for the ascending maneuver, rotational moments of the affected sides were significantly lower by 20.5% and 18.7% compared with their intact counterparts in the single-bundle (P = .015) and double-bundle (P = .05) groups, respectively.
  
  
  CONCLUSIONS
  High-intensity activities combining stair ascending or descending with pivoting produce similar tibial rotation in single- and double-bundle ACL-reconstructed patients. During such maneuvers, the reconstructed knee may be subjected to significantly lower rotational loads compared with the intact knee.
  
  
  METHODS
  Level III, retrospective comparative study.
authors.affiliation: Department of Physical Education and Sports Science, University of Thessaly, Trikala, Greece. tsarouhas_a@yahoo.gr
authors.forename: Alexander
authors.initials: A
authors.lastname: Tsarouhas
authors.forename: Michael
authors.initials: M
authors.lastname: Iosifidis
authors.forename: Giannis
authors.initials: G
authors.lastname: Spyropoulos
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Kotzamitelos
authors.forename: Themistoklis
authors.initials: T
authors.lastname: Tsatalas
authors.forename: Giannis
authors.initials: G
authors.lastname: Giakas
mesh_terms: D000328:Adult; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D000070598:Anterior Cruciate Ligament Injuries; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D001696:Biomechanical Phenomena; D004867:Equipment Design; D005500:Follow-Up Studies; D006801:Humans; D007718:Knee Injuries / Q000601:surgery*; D008297:Male; D012189:Retrospective Studies; D012399:Rotation; D012421:Rupture; D013536:Suture Techniques / Q000295:instrumentation*; D013537:Sutures; D013977:Tibia / Q000601:surgery*; D016896:Treatment Outcome; D014741:Video Recording / Q000295:instrumentation