Imperial College London


Faculty of EngineeringDepartment of Mechanical Engineering




+44 (0)20 7594 7062a.amis




Ms Fabienne Laperche +44 (0)20 7594 7033




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BibTex format

author = {Devitt, BM and Lord, BR and Williams, A and Amis, AA and Feller, JA},
doi = {10.1177/0363546519856331},
journal = {American Journal of Sports Medicine},
pages = {2102--2109},
title = {Biomechanical assessment of a distally fixed lateral extra-articular augmentation procedure in the treatment of anterolateral rotational laxity of the knee},
url = {},
volume = {47},
year = {2019}

RIS format (EndNote, RefMan)

AB - Background:Most lateral extra-articular tenodesis (LET) procedures rely on passing a strip of the iliotibial band (ITB) under the fibular (lateral) collateral ligament and fixing it proximally to the femur. The Ellison procedure is a distally fixed lateral extra-articular augmentation procedure with no proximal fixation of the ITB. It has the potential advantages of maintaining a dynamic element of control of knee rotation and avoiding the possibility of overconstraint.Hypothesis:The modified Ellison procedure would restore native knee kinematics after sectioning of the anterolateral capsule, and closure of the ITB defect would decrease rotational laxity of the knee.Study Design:Controlled laboratory study.Methods:Twelve fresh-frozen cadaveric knees were tested in a 6 degrees of freedom robotic system through 0° to 90° of knee flexion to assess anteroposterior, internal rotation (IR), and external rotation laxities. A simulated pivot shift (SPS) was performed at 0°, 15°, 30°, and 45° of flexion. Kinematic testing was performed in the intact knee and anterolateral capsule–injured knee and after the modified Ellison procedure, with and without closure of the ITB defect. A novel pulley system was used to load the ITB at 30 N for all testing states. Statistical analysis used repeated measures analyses of variance and paired t tests with Bonferroni adjustments.Results:Sectioning of the anterolateral capsule increased anterior drawer and IR during isolated displacement and with the SPS (mean increase, 2° of IR; P < .05). The modified Ellison procedure reduced both isolated and coupled IR as compared with the sectioned state (P < .05). During isolated testing, IR was reduced close to that of the intact state with the modified Ellison procedure, except at 30° of knee flexion, when it was slightly overconstrained. During the SPS, IR with the closed modified Ellison was less than that in the intact state at 15° and 30° of fl
AU - Devitt,BM
AU - Lord,BR
AU - Williams,A
AU - Amis,AA
AU - Feller,JA
DO - 10.1177/0363546519856331
EP - 2109
PY - 2019///
SN - 0363-5465
SP - 2102
TI - Biomechanical assessment of a distally fixed lateral extra-articular augmentation procedure in the treatment of anterolateral rotational laxity of the knee
T2 - American Journal of Sports Medicine
UR -
UR -
UR -
VL - 47
ER -