Abstract
Objective: To evaluate the short-term outcomes of total knee arthroplasty (TKA) performed according to the kinematic alignment (KA) principle using three-dimensional (3D) patient-specific instrumentation (PSI), based on postoperative imaging parameters, functional outcomes, and patient satisfaction.
Methods: This is a prospective study of patients who underwent 3D printed PSI TKAs between July 2023 and July 2024 in Vinmec Time City International General Hospital.
Results: The mean age of the patients was 67 ± 11.3 years, with females accounting for 80%. The mean surgical time was 60 minutes, and no intraoperative changes from the preoperative PSI plan were required in any case. The femorotibial mechanical axis improved from 11.7 ± 1.9° preoperatively to 2.3 ± 2.6° postoperatively. The femoral component external rotation relative to the cylindrical axis (CA) was 1.30 ± 1.00°, the tibial component external rotation relative to the Akagi line was 1.36 ± 1.20°, and the rotational mismatch between the two components was 0.78 ± 1.60°. The mean OKS increased significantly from 16.20 ± 2.11 points preoperatively to 45.03 ± 2.31 points at ≥ 3 months postoperatively (p < 0.001). According to the Beverland satisfaction score, 70% of patients were “Very happy” and 30% were “Happy.” One patient (3.3%) developed knee effusion one month postoperatively and was successfully treated conservatively. No deep infection, clinically significant limitation of range of motion, or anterior knee pain was recorded. Conclusion: Total knee arthroplasty performed according to the kinematic alignment principle with patient-specific instrumentation allows accurate control of limb alignment and component rotation, resulting in excellent functional outcomes and high patient satisfaction, with a low rate of early complications in short-term follow-up.
| Published | 2025-12-25 | |
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| Issue | Vol. 15 No. 7 (2025) | |
| Section | Original Articles | |
| DOI | 10.34071/jmp.2025.7.30 | |
| Keywords | thay khớp gối toàn phần, căn chỉnh động học, PSI, in 3D, Oxford Knee Score total knee arthroplasty, kinematic alignment, patient-specific instrumentation, 3D printing, Oxford Knee Score |
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Copyright (c) 2025 Hue Journal of Medicine and Pharmacy
Kim KK, Howell SM, Won YY. Kinematically aligned total knee arthroplasty with patient-specific instrument. Yonsei Med J. 2020;61(3):201–9.
Rammohan R, Nugent L, Kasture S. Clinical outcomes after using patient-specific instrumentation: is it worth the effort? A minimum 5-year retrospective review of 298 PSI knees. Arch Orthop Trauma Surg. 2023;143(6):3409–22.
Howell SM, Shelton TJ, Hull ML. Implant survival and function ten years after kinematically aligned total knee arthroplasty. J Arthroplasty. 2018;33:3678–84.
Boonen B, Schotanus MG, Kerens B, van der Weegen W, van Drumpt RA, Kort NP. Intra-operative results and radiological outcome of conventional and patientspecific surgery in total knee arthroplasty: a multicentre randomised controlled trial. Knee Surg Sports Traumatol Arthrosc. 2013;21(10):2206–12.
Yoshino N, Takai S, Ohtsuki Y, Hirasawa Y. Computed tomography measurement of the surgical and clinical transepicondylar axis of the distal femur in osteoarthritic knees. J Arthroplasty. 2001;16(4):493–7.
Akagi M, Yamashita E, Nakagawa T, Asano T, Nakamura T. Relationship between frontal knee alignment and reference axes in the distal femur. Clin Orthop Relat Res. 2001;(388):147–56.
Thienpont E, Schwab PE, Paternostre F, Koch P. Rotational alignment of the distal femur: anthropometric measurements with CT-based patient-specific instruments planning show high variability of the posterior condylar angle. Knee Surg Sports Traumatol Arthrosc. 2014;22(12):2995–3002.
Feng Y, Tsai TY, Li JS, Rubash HE, Li G, Freiberg A. Invivo analysis of flexion axes of the knee: femoral condylar motion during dynamic knee flexion. Clin Biomech (Bristol, Avon). 2016;32:102–7.
Yin L, Chen K, Guo L, Cheng L, Wang F, Yang L. Identifying the functional flexion–extension axis of the knee: an in vivo kinematics study. PLoS One. 2015;10(6):e0128877.
Hancock CW, Winston MJ, Bach JM, Davidson BS, Eckhoff DG. Cylindrical axis, not epicondyles, approximates perpendicular to knee axes. Clin Orthop Relat Res. 2013;471(7):2278–83.
Abdel MP, Oussedik S, Parratte S, Lustig S, Haddad FS. Coronal alignment in total knee replacement: historical review, contemporary analysis, and future direction. Bone Joint J. 2014;96:857–62.
Abane L, Anract P, Boisgard S, et al. A comparison of patient-specific and conventional instrumentation for total knee arthroplasty: a multicentre randomised controlled trial. Bone Joint J. 2015;97-B:56–63.
Yan CH, Chiu KY, Ng FY, et al. Comparison between patient-specific instruments and conventional instruments and computer navigation in total knee arthroplasty: a randomized controlled trial. Knee Surg Sports Traumatol Arthrosc. 2015;23:3637–45.
Matharu GS, McBryde CW, Robb CA, Pynsent PB. An analysis of Oxford hip and knee scores following primary hip and knee replacement performed at a specialist centre. Bone Joint J. 2014;96-B:928–35.