Foot & Ankle International - June 2017 - 627

695508

FAIXXX10.1177/1071100717695508Foot & Ankle InternationalCho et al

research-article2017

Article

Functional Outcomes Following Anterior
Transfer of the Tibialis Posterior
Tendon for Foot Drop Secondary
to Peroneal Nerve Palsy

Foot & Ankle International®
2017, Vol. 38(6) 627-633
© The Author(s) 2017
Reprints and permissions:
sagepub.com/journalsPermissions.nav
https://doi.org/10.1177/1071100717695508
DOI: 10.1177/1071100717695508
journals.sagepub.com/home/fai

Byung-Ki Cho, MD1, Kyoung-Jin Park, MD1, Seung-Myung Choi, MD1,
Se-Hyuk Im, MD2, and Nelson F. SooHoo, MD3

Abstract
Background: This retrospective comparative study reports the practical function in daily and sports activities after tibialis
posterior tendon transfer for foot drop secondary to peroneal nerve palsy.
Methods: Seventeen patients were followed for a minimum of 3 years after tibialis posterior tendon transfer for foot drop
secondary to peroneal nerve palsy. Matched controls were used to evaluate the level of functional restoration. Functional
evaluations included American Orthopaedic Foot & Ankle Society (AOFAS) scores, Foot and Ankle Outcome Score
(FAOS), Foot and Ankle Ability Measure (FAAM) scores, and isokinetic muscle strength test. Radiographic evaluation for
the changes of postoperative foot alignment included Meary angle, calcaneal pitch angle, hindfoot alignment angle, and
navicular height.
Results: Mean AOFAS, FAOS, and FAAM scores significantly improved from 65.1 to 86.2, 55.6 to 87.8, and 45.7 to 84.4
points at final follow-up, respectively. However, all functional evaluation scores were significantly lower as compared
to the control group (P < .001). Mean peak torque (60 degrees/sec) of ankle dorsiflexors, plantarflexors, invertors, and
evertors at final follow-up were 7.1 (deficit ratio of 65.4%), 39.2, 9.8, and 7.3 Nm, respectively. These muscle strengths
were significantly lower compared to the control group (P < .001). No significant differences in radiographic measurements
were found, and no patients presented with a postoperative flat foot deformity. One patient (5.9%) needed an ankle-foot
orthosis for occupational activity.
Conclusions: Anterior transfer of the tibialis posterior tendon appears to be an effective surgical option for paralytic
foot drop secondary to peroneal nerve palsy. Although restoration of dorsiflexion strength postoperatively was about 33%
of the normal ankle, function in daily activities and gait ability were satisfactorily improved. In addition, tibialis posterior
tendon transfer demonstrated no definitive radiographic or clinical progression to postoperative flat foot deformity at
intermediate-term follow-up.
Level of Evidence: Level IV, retrospective case series.
Keywords: peroneal nerve palsy, foot drop, tibialis posterior tendon, transfer, functional outcomes

Introduction
Footdrop is defined as the failure of active ankle dorsiflexion, which can result from neurologic, systemic, or traumatic causes.4 Peroneal nerve injury is known to be the
most common cause of trauma-induced foot drop.10
Depending on the cause and severity of foot drop, the initial
conservative treatment includes ankle-foot orthosis, muscle
strengthening rehabilitation, and heel cord stretching exercise. For patients with foot drop that lasts for more than 1
year with little chance of motor function improvement, a
tendon transfer can be considered to re-create a balanced
foot that is plantigrade and functional.4,5,16
Anterior transfer of the tibialis posterior (TP) tendon is
the most common procedure for footdrop following

peroneal nerve injury, and several modifications and
improvements have been made to the original
technique.2,3,4,6,8,15 Although clinical outcomes following
1

Department of Orthopaedic Surgery, College of Medicine, Chungbuk
National University, Cheongju, Korea
2
Department of Orthopaedic Surgery, National Police Hospital, Seoul,
Korea
3
Department of Orthopaedic Surgery, School of Medicine, University of
California, Los Angeles, CA, USA
Corresponding Author:
Byung-Ki Cho, MD, Department of Orthopaedic Surgery, Chungbuk
National University Hospital, 62, Gaesin-dong, Seowon-gu, Cheongju,
Chungbuk, 28644, Korea.
Email: titanick25@naver.com
http://www.sagepub.com/journalsPermissions.nav http://journals.sagepub.com/home/fai
Table of Contents for the Digital Edition of Foot & Ankle International - June 2017
