Systematic Reviews
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Oct 18, 2021; 12(10): 791-801
Published online Oct 18, 2021. doi: 10.5312/wjo.v12.i10.791
Alignment of the hindfoot following total knee arthroplasty: A systematic review
James J Butler, Nathaniel P Mercer, Eoghan T Hurley, Mohammad T Azam, John G Kennedy
James J Butler, Eoghan T Hurley, Department of Orthopedic Surgery, Royal College Surgeons in Ireland, Dublin 18, Ireland
Nathaniel P Mercer, Eoghan T Hurley, Mohammad T Azam, John G Kennedy, Department of Orthopedic Surgery, NYU Langone Health, New York, NY 10002, United States
Author contributions: Butler JJ and Kennedy JG designed the research; Butler JJ and Hurley ET performed the research; Butler JJ, Hurley ET, Mercer NP and Azam MT wrote the paper; Kennedy JG supervised the paper; all authors read and approved the final manuscript.
Conflict-of-interest statement: John G. Kennedy has the following conflicts of interests: American Orthopaedic Foot and Ankle Society: Board or committee member; Arthroscopy Association of North America: Board or committee member; European Society for Sports Traumatology, Knee Surgery and Arthroscopy (ESSKA); Ankle and Foot Associates (AFAS): Board or committee member; International Society for Cartilage Repair of the Ankle: Board or committee member. No other author has any conflicts of interests to disclose.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: John G Kennedy, FRCS, MCh, MD, Doctor, Department of Orthopedic Surgery, NYU Langone Health, 171 Delancey Street, New York, NY 10002, United States.
Received: April 4, 2021
Peer-review started: April 4, 2021
First decision: June 7, 2021
Revised: July 21, 2021
Accepted: August 4, 2021
Article in press: August 4, 2021
Published online: October 18, 2021

There appears to be a close relationship between deformities at the knee joint and at the hindfoot in patients with knee osteoarthritis (OA). Despite this intrinsic link, there is a dearth of studies investigating alterations in hindfoot alignment following total knee arthroplasty (TKA) in patients with knee OA.


To evaluate changes in alignment of the hindfoot following TKA, foot and ankle clinical outcomes in terms of subjective clinical scoring tools following surgical intervention, and to analyse the level of evidence (LOE) and quality of evidence (QOE) of the included studies.


MEDLINE, EMBASE and Cochrane Library databases were systematically reviewed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies reporting changes in the postoperative alignment of the hindfoot following TKA were included. The level and QOE were recorded and assessed.


Eleven studies with a total of 1142 patients (1358 knees) met the inclusion/ exclusion criteria. Six studies were of LOE II and 5 studies were of LOE III. Patients with preoperative varus knee deformity and valgus hindfoot deformity demonstrated improvement in hindfoot alignment post TKA. Patients with preoperative varus knee deformity and varus hindfoot deformity demonstrated no improvement in hindfoot alignment following TKA. Twelve different radiographic parameters were used to measure the alignment of the hindfoot across the included studies, with the tibio-calcaneal angle most frequently utilised (27.3%).


This systematic review demonstrated that the hindfoot may display compensatory changes in alignment following TKA in patients with knee OA. However, the marked heterogeneity between the included studies and poor QOE limits any meaningful cross sectional comparisons between studies. Further, well designed studies are necessary to determine the changes and outcomes of hindfoot alignment following TKA.

Keywords: Total knee arthroplasty, Hindfoot alignment, Hindfoot, Knee osteoarthritis, Varus knee deformity, Valgus hindfoot deformity

Core Tip: This current systematic review has found that correction of deformities at the knee joint following total knee arthroplasty typically resulted in improved changes in the alignment of the hindfoot. However, the poor quality of evidence together with the marked heterogeneity between the included studies, underscores the need for further higher quality studies.