Transtibial pullout repair of medial meniscus posterior root tear restores physiological rotation of the tibia in the knee-flexed position

• Published in: Orthopaedics & traumatology, surgery & research Vol. 105; no. 1; pp. 113 - 117
• Main Authors: Okazaki, Yuki, Furumatsu, Takayuki, Kodama, Yuya, Hino, Tomohito, Kamatsuki, Yusuke, Okazaki, Yoshiki, Masuda, Shin, Miyazawa, Shinichi, Endo, Hirosuke, Tetsunaga, Tomonori, Yamada, Kazuki, Ozaki, Toshifumi
• Format: Journal Article
• Language: English
• Published: France Elsevier Masson SAS 01-02-2019
• Subjects: Adult; Aged; Case-Control Studies; Female; Humans; Knee Joint - diagnostic imaging; Knee Joint - physiopathology; Knee Joint - surgery; Magnetic Resonance Imaging; Male; Medial meniscus; Middle Aged; Patellar Ligament - diagnostic imaging; Posterior root tear; Postoperative Period; Recovery of Function; Retrospective Studies; Rotation; Rupture - diagnostic imaging; Rupture - physiopathology; Rupture - surgery; Tibia - diagnostic imaging; Tibia - physiopathology; Tibial Meniscus Injuries - diagnostic imaging; Tibial Meniscus Injuries - physiopathology; Tibial Meniscus Injuries - surgery; Tibial rotation; Transtibial pullout repair; Young Adult; Tibial rotation; Magnetic resonance imaging; Transtibial pullout repair; Medial meniscus; Posterior root tear
• ISSN: 1877-0568; 1877-0568
• DOI: 10.1016/j.otsr.2018.10.005

Medial meniscus posterior root tear (MMPRT) results in joint overloading and degenerative changes in the knee. Favorable clinical outcomes have been reported after transtibial pullout repair of MMPRT. To date, however, in vivo tibial rotational changes before and after root repair remain poorly understood. The purpose of this study was to investigate postoperative changes in tibial rotation following MMPRT pullout repair.
Pathological external rotation of the tibia in the knee-flexed position is caused by MMPRT and is reduced after transtibial pullout repair.
Fifteen patients who underwent MMPRT pullout repair and 7 healthy volunteers were included. Magnetic resonance imaging examinations were performed in the 10° and 90° knee-flexed positions. The angles between the surgical epicondylar axis and a line between the medial border of the patellar tendon and the apex of the medial tibial spine were measured. Baseline was defined as a line lying at a right angle to the other, and a value was positive and negative when the tibia rotated internally and externally, respectively.
In the volunteer's normal knees, tibial internal rotation was +1.00°±3.27° at 10° flexion and +4.14°±3.46° at 90° flexion. In the MMPRT preoperative knees, tibial internal rotation was +1.07°±3.01° at 10° flexion and +1.27°±2.96° at 90° flexion. In the postoperative knees, tibial internal rotation was +1.60°±2.85° at 10° flexion and +4.33°±2.89° at 90° flexion.
This study demonstrates discontinuity of the MM posterior root may induce a pathological external rotation of the tibia during knee flexion and that MMPRT pullout repair reduces the pathological external rotation of the tibia in the knee-flexed position.
III, comparative retrospective study.