Prediction of post-operative range of motion using intra-operative soft tissue balance in total knee arthroplasty with navigation.
This study evaluated the influence of intra-operative soft tissue balance on post-operative range of motion in patients undergoing posterior-stabilized total knee arthroplasty with navigation. After implantation of all components in 31 consecutive patients, the joint component gap was measured manually with the knee at 0°, 90°, and 120° as guided by a navigation system. We designated soft tissue balance as the absolute difference between varus stress and valgus stress (medio-lateral laxity). Changes in medio-lateral laxity were calculated from 120° to 90°, 120° to 0°, and 90° to 0°. Correlations among post-operative flexion angles and pre-operative flexion angles, intra-operative flexion angle after implantation, soft tissue balance, and the changes were analyzed. The mean pre- and post-operative knee flexion angles were 114 ± 20° and 127 ± 9°, respectively. The mean intra-operative flexion angle was 137 ± 6°. The post-operative flexion angle was positively correlated with the pre-operative flexion angle and intra-operative flexion angle after implantation. The change in soft tissue balance between 120° and 90° showed a positive correlation with the post-operative flexion angle. In conclusion, Assessment of intra-operative soft tissue balance could predict post-operative flexion angle.
a Department of Orthopaedic Surgery, Mie University Graduate School of Medicine , Tsu City, Mie , Japan.
Masahiro
M
Hasegawa
a Department of Orthopaedic Surgery, Mie University Graduate School of Medicine , Tsu City, Mie , Japan.
Hisatsugu
H
Takagita
a Department of Orthopaedic Surgery, Mie University Graduate School of Medicine , Tsu City, Mie , Japan.
Akihiro
A
Sudo
D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D001696:Biomechanical Phenomena; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007719:Knee Joint; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000379:methods*; D020370:Osteoarthritis, Knee / Q000503:physiopathology / Q000601:surgery*; D011184:Postoperative Period; D011446:Prospective Studies; D016059:Range of Motion, Articular / Q000502:physiology*; D025321:Surgery, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome
Navigation;; range of motion;; soft tissue balance;; total knee arthroplasty