title: Anatomic double-bundle anterior cruciate ligament reconstruction using hamstring tendons with minimally required initial tension.
abstract: OBJECTIVE
  Our purpose was to clarify the clinical outcomes at 2 years after anatomic double-bundle anterior cruciate ligament (ACL) reconstruction with 20 N of the initial tension, which was the minimally required initial tension to perform the reconstruction successfully according to our previous report about the pre-tension necessary to restore the laxity found in the opposite knee (7.3 N; range, 2.2 to 14 N).
  
  
  METHODS
  Of 64 patients who underwent anatomic double-bundle ACL reconstruction with autogenous semitendinosus tendon, 45 were periodically examined for 2 years. Two double-looped grafts were fixed with EndoButton CL devices (Smith & Nephew Endoscopy, Andover, MA) on the femoral side and Double Spike Plates (Smith & Nephew Endoscopy) on the tibial side, while a total of 20 N of initial tension (10 N to each graft) was applied at 20° of knee flexion. The International Knee Documentation Committee Knee Examination Form and Lysholm score were used for the subjective assessment, whereas range of motion and knee stability were evaluated as the objective assessment. Grafts were evaluated in 25 patients with second-look arthroscopy.
  
  
  RESULTS
  According to the International Knee Documentation Committee subjective assessment, 62% of knees were graded as normal and 38% as nearly normal. The Lysholm score was 72 points in the preoperative period and improved to 99 points at 2 years' follow-up. A loss of knee extension of less than 3° was found in 2 patients. The pivot-shift test was evaluated as negative in all patients except for 5 as a glide. KT-2000 knee arthrometer side-to-side difference (MEDmetric, San Diego, CA) was 0.1 ± 0.9 mm at 2 years' follow-up. Of the subset of grafts evaluated by second-look arthroscopy, most were considered to have good synovial coverage and to be taut.
  
  
  CONCLUSIONS
  The anatomic double-bundle ACL reconstruction with 20 N of low initial tension yielded good clinical outcomes at 2 years postoperatively, and second-look arthroscopic findings were excellent.
  
  
  METHODS
  Level IV, therapeutic case series.
authors.affiliation: Department of Sports Medicine, Osaka Kousei-Nenkin Hospital, Osaka, Japan. ta-mae@unim.ac.jp
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Mae
authors.forename: Konsei
authors.initials: K
authors.lastname: Shino
authors.forename: Norinao
authors.initials: N
authors.lastname: Matsumoto
authors.forename: Takashi
authors.initials: T
authors.lastname: Natsu-Ume
authors.forename: Kenji
authors.initials: K
authors.lastname: Yoneda
authors.forename: Hideki
authors.initials: H
authors.lastname: Yoshikawa
authors.forename: Minoru
authors.initials: M
authors.lastname: Yoneda
mesh_terms: D000293:Adolescent; D000328:Adult; D016118:Anterior Cruciate Ligament / Q000033:anatomy & histology / Q000601:surgery*; D001182:Arthroscopy / Q000379:methods; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007719:Knee Joint / Q000473:pathology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery; D016059:Range of Motion, Articular; D019651:Plastic Surgery Procedures / Q000379:methods*; D012420:Running; D024162:Second-Look Surgery / Q000379:methods; D013314:Stress, Mechanical; D013710:Tendons / Q000601:surgery* / Q000637:transplantation*; D016896:Treatment Outcome; D016474:Weight-Bearing