title: Factors that influence the intra-articular rupture pattern of the ACL graft following single-bundle reconstruction.
abstract: OBJECTIVE
  The number of revision anterior cruciate ligament (ACL) surgeries performed annually continues to rise. The purpose of this study was to determine the most common rupture pattern in ACL revision cases after previous single-bundle reconstruction. The second aim was to determine the relationship between rupture pattern and patient-specific factors (age, gender, time between the initial ACL reconstruction and re-injury, and etiology/mechanism of failure) and surgical factors (graft type, tunnel angle).
  
  
  METHODS
  This was a cohort study of 60 patients that underwent revision ACL surgery after previous single-bundle ACL reconstruction. Three sports medicine-trained orthopedic surgeons reviewed the arthroscopic videos and determined the rupture pattern of the grafts. The rupture pattern was then correlated to the above-mentioned factors.
  
  
  RESULTS
  The inter-observer agreement had a kappa of 0.7. The most common rupture pattern after previous single-bundle ACL reconstruction is elongation of the graft. This is different from the native ACL, which displays more proximal ruptures. With the use of autograft tissue and after a longer period of time, the rupture pattern in revision surgery is more similar to that of the native ACL.
  
  
  CONCLUSIONS
  The most common rupture pattern after previous single-bundle reconstruction was elongation of the graft. Factors that influenced the rupture pattern were months between ACL reconstruction and re-injury and graft type.
  
  
  METHODS
  Cohort study, Level IV.
authors.affiliation: Department of Orthopaedic Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA, 15213, USA.
authors.forename: Carola F
authors.initials: CF
authors.lastname: van Eck
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Kropf
authors.forename: James R
authors.initials: JR
authors.lastname: Romanowski
authors.forename: Bryson P
authors.initials: BP
authors.lastname: Lesniak
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Tranovich
authors.forename: C Niek
authors.initials: CN
authors.lastname: van Dijk
authors.forename: Freddie H
authors.initials: FH
authors.lastname: Fu
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000704:Analysis of Variance; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D000070598:Anterior Cruciate Ligament Injuries; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D001182:Arthroscopy; D016009:Chi-Square Distribution; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007718:Knee Injuries / Q000000981:diagnostic imaging / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D010147:Pain Measurement; D011446:Prospective Studies; D011859:Radiography; D016059:Range of Motion, Articular / Q000502:physiology; D012008:Recurrence; D012086:Reoperation / Q000379:methods; D012307:Risk Factors; D012422:Rupture, Spontaneous / Q000000981:diagnostic imaging / Q000601:surgery; D012737:Sex Factors; D018709:Statistics, Nonparametric; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult