title: The effect of notchplasty on tunnel widening in anterior cruciate ligament reconstruction.
abstract: OBJECTIVE
  To investigate changes in femoral tunnel diameter, dimension, and volume after anterior cruciate ligament reconstruction with notchplasty.
  
  
  METHODS
  Porcine knee specimens were divided into 2 groups of 10 specimens each. Group A did not receive notchplasty. A 2-mm notchplasty was conducted in group B. Seven-millimeter-diameter femoral tunnels were drilled and a doubled flexor digitorum profundus tendon was inserted and fixed with an EndoButton (Smith & Nephew, Andover, MA) in each knee specimen. Samples were mounted on a materials testing machine. Each group was preloaded at 10 N and subjected to 20 loading cycles (between 0 and 40 N), followed by 1,000 loading cycles in the elastic region (between 10 and 150 N). High-resolution computed tomography with 1.0-mm slices was conducted with all samples before and after testing. A 3-dimensional model was constructed to evaluate the degree of the tunnel change.
  
  
  RESULTS
  In group B the mean longest diameter and dimension of the femoral tunnel significantly increased after the test (P = .005 and P = .001, respectively). The volumetric loss of bony structure after the test in group B was significantly greater than that in group A (P = .039). Meanwhile, no significant difference was found before and after the test in terms of tunnel diameter, dimension, and volumetric loss around the tunnel in group A.
  
  
  CONCLUSIONS
  The intra-articular orifice of the femoral tunnel was enlarged after the uniaxial cyclic loading test after notchplasty. An enlarged tunnel orifice may lead to a discrepancy between the tunnel and the graft at the tunnel aperture.
  
  
  CONCLUSIONS
  The data may have an implication that suspensory fixation with a notchplasty has a negative effect on the full graft accommodation at the tunnel aperture. Aperture widening may affect graft positioning, leading to subtle changes in graft biomechanics and laxity.
authors.affiliation: Department of Orthopedic Surgery, Hallym University Medical Center, Dongtan, South Korea.
authors.forename: Young-Jin
authors.initials: YJ
authors.lastname: Seo
authors.affiliation: Department of Orthopedic Surgery, Hallym University Medical Center, Dongtan, South Korea. Electronic address: ybw1999@gmail.com.
authors.forename: Yon-Sik
authors.initials: YS
authors.lastname: Yoo
authors.affiliation: HiLab, Korea University of Technology and Education, Cheonan, South Korea.
authors.forename: Yoon Sang
authors.initials: YS
authors.lastname: Kim
authors.affiliation: HiLab, Korea University of Technology and Education, Cheonan, South Korea.
authors.forename: Seong-Wook
authors.initials: SW
authors.lastname: Jang
authors.affiliation: Department of Orthopedic Surgery, Hallym University Medical Center, Dongtan, South Korea.
authors.forename: Si Young
authors.initials: SY
authors.lastname: Song
authors.affiliation: Department of Orthopedic Surgery, Hallym University Medical Center, Dongtan, South Korea.
authors.forename: Yoon Suk
authors.initials: YS
authors.lastname: Hyun
authors.affiliation: Department of Orthopedic Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, U.S.A.
authors.forename: Patrick
authors.initials: P
authors.lastname: Smolinski
authors.affiliation: Department of Orthopedic Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, U.S.A.
authors.forename: Freddie H
authors.initials: FH
authors.lastname: Fu
mesh_terms: D000818:Animals; D016118:Anterior Cruciate Ligament / Q000601:surgery; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D015519:Bone Density; D005260:Female; D005269:Femur / Q000601:surgery*; D008297:Male; D010027:Osteotomy / Q000379:methods*; D012737:Sex Factors; D013552:Swine