title: The influence of femoral tunnel length on graft rupture after anterior cruciate ligament reconstruction.
abstract: BACKGROUND
  For ACL reconstruction, the minimum length of the femoral tunnel and the flexor tendon graft length needed within the tunnel for proper integration have not been defined. The aim of this study was to assess whether a short tunnel is a risk factor for poor prognosis and re-rupture by comparing the outcomes of patients with short femoral tunnels to those of patients with longer tunnels.
  
  
  METHODS
  A retrospective observational study of 80 patients who underwent ACL reconstruction using flexor tendons via the medial transportal or transtibial technique was performed. Patients were categorized according to the amount of graft within the tunnel: ≤1.5 versus >1.5 cm; ≤2 versus >2 cm; ≤2.5 versus >2.5 cm; and ≤1.5 versus >2.5 cm. Patients were evaluated 2 years after surgery by performing a physical examination (Lachman, pivot shift and anterior drawer tests), using a KT1000 arthrometer, calculating objective and subjective International Knee Documentation Committee scores, conducting the Lysholm score, and recording re-ruptures.
  
  
  RESULTS
  Of the 80 operated patients, nine were lost to follow-up. Comparative assessment of the patients with different amounts of graft within the tunnel indicated no significant differences in the evaluated outcomes, except for positive Lachman test results, which were more frequent in patients with tunnels with ≤2 cm of graft than in those with tunnels with >2 cm of graft.
  
  
  CONCLUSIONS
  The amount of graft within the femoral tunnel does not appear to be a risk factor for clinical instability of the knee or re-rupture of the graft.
  
  
  METHODS
  case series, level IV.
  
  
  METHODS
  Case series, level IV.
authors.affiliation: Knee Group of the Department of Orthopedics and Traumatology of Santa Casa de Misericórdia of São Paulo, Santa Casa School of Medical Sciences, São Paulo-Fernandinho Simonsen Pavilion, São Paulo, Brazil. luizgbg@terra.com.br.|, Pascal, 1292, Ap91, Campo Belo, São Paulo, São Paulo, 04616-004, Brazil. luizgbg@terra.com.br.
authors.forename: Luiz Gabriel Betoni
authors.initials: LGB
authors.lastname: Guglielmetti
authors.affiliation: Knee Group of the Department of Orthopedics and Traumatology of Santa Casa de Misericórdia of São Paulo, Santa Casa School of Medical Sciences, São Paulo-Fernandinho Simonsen Pavilion, São Paulo, Brazil.
authors.forename: Leandro Girardi
authors.initials: LG
authors.lastname: Shimba
authors.affiliation: Knee Group of the Department of Orthopedics and Traumatology of Santa Casa de Misericórdia of São Paulo, Santa Casa School of Medical Sciences, São Paulo-Fernandinho Simonsen Pavilion, São Paulo, Brazil.
authors.forename: Leonardo Cantarelli
authors.initials: LC
authors.lastname: do Santos
authors.affiliation: Knee Group of the Department of Orthopedics and Traumatology of Santa Casa de Misericórdia of São Paulo, Santa Casa School of Medical Sciences, São Paulo-Fernandinho Simonsen Pavilion, São Paulo, Brazil.
authors.forename: Fabrício Roberto
authors.initials: FR
authors.lastname: Severino
authors.affiliation: Knee Group of the Department of Orthopedics and Traumatology of Santa Casa de Misericórdia of São Paulo, Santa Casa School of Medical Sciences, São Paulo-Fernandinho Simonsen Pavilion, São Paulo, Brazil.
authors.forename: Nilson Roberto
authors.initials: NR
authors.lastname: Severino
authors.affiliation: Knee Group of the Department of Orthopedics and Traumatology of Santa Casa de Misericórdia of São Paulo, Santa Casa School of Medical Sciences, São Paulo-Fernandinho Simonsen Pavilion, São Paulo, Brazil.
authors.forename: Patrícia Maria
authors.initials: PM
authors.lastname: de Moraes Barros Fucs
authors.affiliation: Knee Group of the Department of Orthopedics and Traumatology of Santa Casa de Misericórdia of São Paulo, Santa Casa School of Medical Sciences, São Paulo-Fernandinho Simonsen Pavilion, São Paulo, Brazil.
authors.forename: Ricardo
authors.initials: R
authors.lastname: de Paula Leite Cury
mesh_terms: D000293:Adolescent; D000328:Adult; D059549:Anterior Cruciate Ligament Reconstruction / Q000009:adverse effects* / Q000379:methods* / Q000534:rehabilitation; D001182:Arthroscopy; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D008297:Male; D011379:Prognosis; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D012421:Rupture; D013710:Tendons / Q000637:transplantation; D019737:Transplants / Q000293:injuries / Q000601:surgery; D055815:Young Adult
keywords: ACL reconstruction; Graft failure; Hamstring tendon; Tunnel length