Accuracy of soft tissue balancing in TKA: comparison between navigation-assisted gap balancing and conventional measured resection

• Published in: Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA sports traumatology, arthroscopy : official journal of the ESSKA, 2010-03, Vol.18 (3), p.381-387
• Main Authors: Lee, Dae-Hee, Park, Jong-Hoon, Song, Dong-Ik, Padhy, Debabrata, Jeong, Woong-Kyo, Han, Seung-Beom
• Format: Article
• Language: English
• Subjects: Accuracy; Aged; Aged, 80 and over; Arthroplasty, Replacement, Knee - methods; Biomechanical Phenomena; Female; Hospitals; Humans; Joint replacement surgery; Kinematics; Knee; Knee Joint - physiology; Knees; Male; Measurement; Medicine; Medicine & Public Health; Middle Aged; Navigation systems; Orthopedics; Osteoarthritis, Knee - surgery; Range of Motion, Articular; Recovery of Function; Sports; Surgeons; Surgery; Surgery, Computer-Assisted; Transplants & implants
• ISSN: 0942-2056; 1433-7347
• DOI: 10.1007/s00167-009-0983-x

Equalized rectangular extension and flexion gaps are considered desirable to ensure proper kinematics in total knee arthroplasty (TKA). We compared soft tissue balancing in TKAs performed using navigation-assisted gap-balancing (60 knees) and conventional measured resection (56 knees). The outlier of soft tissue balancing was defined as a gap difference >3 mm between the medial and lateral sides in 90° flexion and extension. Medial or lateral outliers in extension or flexion were observed in 12% (7 of 60) navigation TKAs and 25% (14 of 56) conventional TKAs ( p  = 0.028). There were more outliers in flexion–extension gap difference on the medial side in the conventional (23%) than in the navigation-assisted (5%) group ( p  = 0.025). However, the proportion of flexion gap difference, extension gap difference, and lateral gap difference outliers did not differ significantly between the two groups ( n.s. ). Additionally, clinicoradiologic outcomes were similar for the two groups except for the postoperative mechanical axis outlier ( p  = 0.012). Navigation-assisted soft tissue balancing in TKA reduced not only the postoperative alignment outlier, but also the medial gap difference and achieved a more rectangular flexion and extension gap compared with conventional TKA.