Five-year changes in gait biomechanics after concomitant high tibial osteotomy and ACL reconstruction in patients with medial knee osteoarthritis.
BACKGROUND
Concomitant high tibial osteotomy (HTO) and anterior cruciate ligament (ACL) reconstruction is a combined surgical procedure intended to improve kinematics and kinetics in the unstable ACL-deficient knee with varus malalignment and medial compartment knee osteoarthritis (OA).


OBJECTIVE
To investigate 5-year changes in gait biomechanics as well as radiographic and patient-reported outcomes bilaterally after unilateral, concomitant medial opening wedge HTO and ACL reconstruction.


METHODS
Controlled laboratory study.


METHODS
A total of 33 patients (mean ± SD age, 40 ± 9 years) with varus malalignment (mean mechanical axis angle, -5.9° ± 2.9°), medial compartment knee OA, and ACL deficiency completed 3-dimensional gait analysis preoperatively and 2 and 5 years postoperatively. Primary outcomes were the peak external knee adduction (first peak) and flexion moments. Secondary outcomes were the peak external knee extension and transverse plane moments, peak knee angles in all 3 planes, radiographic static knee alignment measures (mechanical axis angle and posterior tibial slope), and the Knee injury and Osteoarthritis Outcome Score (KOOS).


RESULTS
There was a substantial decrease in the knee adduction moment in the surgical limb (%BW × H, -1.49; 95% CI, -1.75 to -1.22) and a slight increase in the nonsurgical limb (%BW × H, 0.16; 95% CI, 0.03 to 0.30) from preoperatively to 5 years postoperatively. There was also a decrease in the knee flexion moment for both the surgical (%BW × H, -0.67; 95% CI, -1.19 to -0.15) and nonsurgical limbs (%BW × H, -1.06; 95% CI, -1.49 to -0.64). Secondary outcomes suggested that substantial improvements were maintained at 5 years, although smaller declines were observed in several measures and in both limbs from 2 to 5 years.


CONCLUSIONS
Changes in the peak external moments about the knee in all 3 planes during walking were observed 5 years after concomitant medial opening wedge HTO and ACL reconstruction. These findings are consistent with an intended, sustained shift in the mediolateral distribution of knee loads.


CONCLUSIONS
These findings suggest that concomitant HTO and ACL reconstruction results in substantial changes in gait biomechanics. Future clinical research comparing treatment strategies is both warranted and required for this relatively uncommon but seemingly biomechanically efficacious procedure.
Wolf Orthopaedic Biomechanics Laboratory, Fowler Kennedy Sport Medicine Clinic, University of Western Ontario, London, Ontario, Canada School of Physical Therapy, Faculty of Health Sciences, University of Western Ontario, London, Ontario, Canada.
Kendal
K
Marriott
Wolf Orthopaedic Biomechanics Laboratory, Fowler Kennedy Sport Medicine Clinic, University of Western Ontario, London, Ontario, Canada School of Physical Therapy, Faculty of Health Sciences, University of Western Ontario, London, Ontario, Canada tbirming@uwo.ca rgiffin@uwo.ca.
Trevor B
TB
Birmingham
School of Medical and Applied Science, Central Queensland University, Rockhampton, Queensland, Australia.
Crystal O
CO
Kean
Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada.
Catherine
C
Hui
Wolf Orthopaedic Biomechanics Laboratory, Fowler Kennedy Sport Medicine Clinic, University of Western Ontario, London, Ontario, Canada Department of Mechanical and Materials Engineering, Faculty of Engineering, University of Western Ontario, London, Ontario, Canada.
Thomas R
TR
Jenkyn
Wolf Orthopaedic Biomechanics Laboratory, Fowler Kennedy Sport Medicine Clinic, University of Western Ontario, London, Ontario, Canada Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada tbirming@uwo.ca rgiffin@uwo.ca.
J Robert
JR
Giffin
D000328:Adult; D000368:Aged; D059549:Anterior Cruciate Ligament Reconstruction / Q000379:methods*; D001696:Biomechanical Phenomena / Q000502:physiology; D005260:Female; D005684:Gait / Q000502:physiology*; D006801:Humans; D007593:Joint Instability / Q000503:physiopathology / Q000601:surgery; D007700:Kinetics; D007718:Knee Injuries / Q000503:physiopathology / Q000601:surgery; D007719:Knee Joint / Q000601:surgery; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000503:physiopathology* / Q000601:surgery; D010027:Osteotomy / Q000379:methods*; D016059:Range of Motion, Articular / Q000502:physiology; D013977:Tibia / Q000601:surgery; D016138:Walking / Q000502:physiology
anterior cruciate ligament reconstruction; gait biomechanics; high tibial osteotomy