title: Comparative risk of common peroneal nerve injury in far anteromedial portal drilling and transtibial drilling in anatomical double-bundle ACL reconstruction.
abstract: OBJECTIVE
  The purpose of this study was to investigate the risk of common peroneal nerve injury in FM drilling as compared to transtibial drilling in anatomical double-bundle ACL reconstruction.
  
  
  METHODS
  Ten cadaveric knees without ligament injury or significant arthritis were used for this study. Knees were secured at 90° and 120° of flexion. In transtibial drilling groups, a guide pin was drilled through either the anteromedial bundle (AMB) or posterolateral bundle (PLB) tibial insertion site to either the AMB or PLB femoral insertion site (tibial insertion site-femoral insertion site: AM-AM, PL-PL, PL-AM and AM-PL). In FM drilling groups (FM-AM and FM-PL),the pin was drilled at the AMB or PLB femoral insertion site through the FM. We measured the shortest distance between the point at which the pin ran through the lateral cortex of the femur and the ipsilateral common peroneal nerve at a knee flexion of 90° and 120°.
  
  
  RESULTS
  At a knee flexion of 90°, the shortest mean distance to the common peroneal nerve was 15.3 mm in the FM-PL group, 13.4 mm in the FM-AM group, 27.9 mm in the PL-PL group, 30.8 mm in the AM-AM group, 37.8 mm in the PL-AM group and 29.5 mm in the AM-PL group. At a knee of flexion 120°, the mean distance was 17.3 mm in the FM-PL group, 18.1 mm in the FM-AM group, 32.2 mm in the PL-PL group, 36.6 mm in the AM-AM group, 38.0 mm in the PL-AM group and 35.2 mm in the AM-PL group. Significant differences were observed between 90° and 120° of knee flexion in the FM-AM, PL-PL, AM-AM and AM-PL groups (P < 0.05). Significant differences were observed at flex 90° between the FM-AM group and AM-AM group, and between the FM-AM group and PL-AM group. Significant differences were observed at flex 120° between the FM-AM group and AM-AM group, between the FM-AM group and PL-AM group and between the FM-PL group and AM-PL group.
  
  
  CONCLUSIONS
  The distance to the peroneal nerve in FM drilling was significantly longer at 120° than at 90° of knee flexion. Therefore, the risk of peroneal injury using FM drilling should decrease at a higher angle of knee flexion.
authors.affiliation: Department of Orthopedic Surgery, Nagoya City University Graduate School of Medical Sciences, 1-Kawasumi, Mizuho-Cho, Mizuho-Ku, Nagoya, 467-8601, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Otani
authors.forename: M
authors.initials: M
authors.lastname: Nozaki
authors.forename: M
authors.initials: M
authors.lastname: Kobayashi
authors.forename: H
authors.initials: H
authors.lastname: Goto
authors.forename: K
authors.initials: K
authors.lastname: Tawada
authors.forename: Y
authors.initials: Y
authors.lastname: Waguri-Nagaya
authors.forename: H
authors.initials: H
authors.lastname: Okamoto
authors.forename: H
authors.initials: H
authors.lastname: Iguchi
authors.forename: N
authors.initials: N
authors.lastname: Watanabe
authors.forename: T
authors.initials: T
authors.lastname: Otsuka
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016118:Anterior Cruciate Ligament / Q000601:surgery*; D000070598:Anterior Cruciate Ligament Injuries; D001182:Arthroscopy; D001858:Bone Nails; D002102:Cadaver; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010543:Peroneal Nerve / Q000293:injuries* / Q000601:surgery; D016059:Range of Motion, Articular; D019651:Plastic Surgery Procedures / Q000009:adverse effects* / Q000379:methods; D012306:Risk; D013977:Tibia / Q000601:surgery*