Clinical and Functional Evaluation of Total Knee Arthroplasty Using a Mechanical Alignment Philosophy: A Case Series
DOI:
https://doi.org/10.63403/re.v33i1.475Keywords:
Knee arthroplasty, Functional Results, WOMAC, SF-12, mechanical alignmentAbstract
Introduction: total knee arthroplasty (TKA) is one of the most commonly performed orthopedic procedures worldwide, with sustained growth associated with population aging and the increasing prevalence of knee osteoarthritis and obesity. Mechanical alignment remains the standard technique, although alternatives such as kinematic alignment have emerged. In Uruguay, published evidence on the clinical and functional outcomes of TKA with mechanical alignment is limited.
Objectives: the main objective of this study was to evaluate the functional outcomes and complications of a series of total knee arthroplasties implanted using mechanical alignment.
Materials and methods: a descriptive observational study with retrospective data collection was conducted. Patients older than 18 years who underwent primary mechanically aligned TKA at a Highly Specialized Medical Institute (IMAE) and were followed in our outpatient clinic between May 2022 and October 2025, with a minimum follow-up of 12 months, were included. Data were obtained through telephone interviews administering the Spanish validated WOMAC and SF-12 questionnaires, as well as the Visual Analog Scale (VAS) for pain. Postoperative complications were recorded, and descriptive statistics were used.
Results: a total of 36 arthroplasties in 32 patients were analyzed; 78% were women, with a mean age of 70.5 years and a mean follow-up of 24.4 months. The mean total WOMAC score was 6.0 points, indicating low pain and stiffness levels with adequate functional capacity. The SF-12 showed a physical component score of 48.8 and a mental component score of 59.3, consistent with good perceived quality of life. The mean VAS pain score was 2.1. Two infections (6%) and one reintervention for stiffness (3%) were recorded.
Conclusion: mechanically aligned TKA demonstrated favorable functional outcomes, adequate pain control, and a complication rate within expected ranges in this retrospective series. However, due to the observational design, limited sample size, and absence of a comparison group, the results should be interpreted with caution. Prospective comparative studies with longer follow-up are required to confirm these findings.
Level of evidence: IV. Retrospective Cohort Study
Downloads
References
Price AJ, Alvand A, Troelsen A, et al. Knee replacement. Lancet. 2018;392(10158):1672-1682. doi: https://doi.org/10.1016/S0140-6736(18)32344-4 DOI: https://doi.org/10.1016/S0140-6736(18)32344-4
Maradit Kremers H, Larson DR, Crowson CS,et al.. Prevalence of total hip and Knee replacement in the United States. J Bone Joint Surg Am. 2015;97(17):1386-1397. doi: https://doi.org/10.2106/JBJS.N.01141 DOI: https://doi.org/10.2106/JBJS.N.01141
Singh JA. Epidemiology of knee and hip arthroplasty: a systematic review. Open Orthop J. 2011;5:80-85. doi: https://doi.org/10.2174/1874325001105010080 DOI: https://doi.org/10.2174/1874325001105010080
American Academy of Orthopaedic Surgeons. Knee replacement surgery by the numbers [internet]. Illinois: The center. [citado 2025 Nov 15]. Disponible en: https://www.thecenteroregon.com/medical-blog/knee-replacement-surgery-by-the-numbers/
Inacio MCS, Paxton EW, Graves SE, Namba RS, Nemes S. Projected increase in total knee arthroplasty in the United States - an alternative projection model. Osteoarthritis Cartilage. 2017;25(11):1797-1803. doi: https://doi.org/10.1016/j.joca.2017.07.022 DOI: https://doi.org/10.1016/j.joca.2017.07.022
Ackerman IN, Bohensky MA, de Steiger R, et al. Lifetime risk of primary total hip replacement surgery for osteoarthritis from 2003 to 2013: a multinational analysis using national registry data. Arthritis Care Res (Hoboken). 2017;69(11):1659-1667. doi: https://doi.org/10.1002/acr.23197 DOI: https://doi.org/10.1002/acr.23197
Shan L, Shan B, Suzuki A, Nouh F, Saxena A. Intermediate and long-term quality of life after total knee replacement: a systematic review and meta-analysis: a systematic review and meta-analysis. J Bone Joint Surg Am. 2015;97(2):156-168. doi: https://doi.org/10.2106/JBJS.M.00372 DOI: https://doi.org/10.2106/JBJS.M.00372
Skou ST, Roos EM, Laursen MB, et al. A randomized, controlled trial of total knee replacement. N Engl J Med. 2015;373(17):1597-606. doi: https://doi.org/10.1056/NEJMoa1505467 DOI: https://doi.org/10.1056/NEJMoa1505467
Bourne RB, Chesworth BM, Davis AM, Mahomed NN, Charron KDJ. Patient satisfaction after total knee arthroplasty: who is satisfied and who is not? Clin Orthop Relat Res. 2010;468(1):57–63. doi: https://doi.org/10.1007/s11999-009-1119-9 DOI: https://doi.org/10.1007/s11999-009-1119-9
Ranawat CS, Flynn WF Jr, Saddler S, Hansraj KK, Maynard MJ. Long-term results of the total condylar knee arthroplasty. A 15-year survivorship study. Clin Orthop Relat Res. 1993;(286):94-102. DOI: https://doi.org/10.1097/00003086-199301000-00015
Hofmann AA, Bachus KN, Wyatt RW. Effect of the tibial cut on subsidence following total knee arthroplasty. Clin Orthop Relat Res. 1991;269(269):63–69. DOI: https://doi.org/10.1097/00003086-199108000-00011
Dennis D, Komistek R, Scuderi G, et al. In vivo three-dimensional determination of kinematics for subjects with a normal knee or a unicompartmental or total knee replacement. J Bone Joint Surg Am. 2001;83-A(Suppl 2 Pt 2):104-115. doi: https://doi.org/10.2106/00004623-200100022-00008 DOI: https://doi.org/10.2106/00004623-200100022-00008
Nam D, Nunley RM, Barrack RL. Patient dissatisfaction following total knee replacement: a growing concern? Bone Joint J. 2014;96-B(11 Suppl A):96-100. doi: https://doi.org/10.1302/0301-620X.96B11.34152 DOI: https://doi.org/10.1302/0301-620X.96B11.34152
Baker PN, van der Meulen JH, Lewsey J, Gregg PJ; National Joint Registry for England and Wales. The role of pain and function in determining patient satisfaction after total knee replacement. Data from the National Joint Registry for England and Wales. J Bone Joint Surg Br. 2007;89(7):893-900. doi: https://doi.org/10.1302/0301-620X.89B7.19091 DOI: https://doi.org/10.1302/0301-620X.89B7.19091
Gunaratne R, Pratt DN, Banda J, Fick DP, Khan RJK, Robertson BW. Patient dissatisfaction following total knee arthroplasty: a systematic review of the literature. J Arthroplasty. 2017;32(12):3854-3860. doi: https://doi.org/10.1016/j.arth.2017.07.021 DOI: https://doi.org/10.1016/j.arth.2017.07.021
Choi YJ, Ra HJ. Patient satisfaction after total knee arthroplasty. Knee Surg Relat Res. 2016;28(1):1-15. doi: https://doi.org/10.5792/ksrr.2016.28.1.1. DOI: https://doi.org/10.5792/ksrr.2016.28.1.1
Rivière C, Iranpour F, Auvinet E, et al. Alignment options for total knee arthroplasty: a systematic review. Orthop Traumatol Surg Res. 2017;103(7):1047-1056. doi: https://doi.org/10.1016/j.otsr.2017.07.010 DOI: https://doi.org/10.1016/j.otsr.2017.07.010
Howell SM, Hodapp EE, Vernace JV, Hull ML, Meade TD. Are undesirable contact kinematics minimized after kinematically aligned total knee arthroplasty? An intersurgeon analysis of consecutive patients. Knee Surg Sports Traumatol Arthrosc. 2013;21(10):2281-2287. doi: https://doi.org/10.1007/s00167-012-2220-2 DOI: https://doi.org/10.1007/s00167-012-2220-2
Hiranaka T. Current concept: personalized alignment total knee arthroplasty as a contrast to classical mechanical alignment total knee arthroplasty. Arthroplasty. 2024;6(1):23. doi: https://doi.org/10.1186/s42836-024-00246-2 DOI: https://doi.org/10.1186/s42836-024-00246-2
Escobar A, Quintana JM, Bilbao A, Azkárate J, Güenaga JI. Validation of the Spanish version of the WOMAC questionnaire for patients with hip or knee osteoarthritis. Western Ontario and McMaster Universities Osteoarthritis Index. Clin Rheumatol. 2002;21(6):466-471. doi: https://doi.org/10.1007/s100670200117 DOI: https://doi.org/10.1007/s100670200117
Batlle-Gualda E, Esteve-Vives J, Riera MP, Hargreaves R, Cutts J. Traducción y adaptación al español del cuestionario WOMAC específico para artrosis de rodilla y cadera. Rev Esp Reumatol. 1999;26(2):0.
Howell SM, Shelton TJ, Hull ML. implant survival and function ten years after kinematically aligned total knee arthroplasty. J Arthroplasty. 2018;33(12):3678-3684. doi: https://doi.org/10.1016/j.arth.2018.07.020 DOI: https://doi.org/10.1016/j.arth.2018.07.020
Young SW, Sullivan NPT, Walker ML, Holland S, Bayan A, Farrington B. No difference in 5-year clinical or radiographic outcomes between kinematic and mechanical alignment in TKA: a randomized controlled trial. Clin Orthop Relat Res. 2020;478(6):1271-1279. doi: https://doi.org/10.1097/CORR.0000000000001150 DOI: https://doi.org/10.1097/CORR.0000000000001150
Martín-Hernández C, Sanz-Sainz M, Revenga-Giertych C, et al. Navigated versus conventional total knee arthroplasty: a prospective study at three years follow-up. Rev Esp Cir Ortop Traumatol (Engl Ed). 2018;62(4):282-289. doi: https://doi.org/10.1016/j.recot.2018.01.001 DOI: https://doi.org/10.1016/j.recote.2018.01.005
Young SW, Walker ML, Bayan A, Briant-Evans T, Pavlou P, Farrington B. The Chitranjan S. Ranawat Award: no difference in 2-year functional outcomes using kinematic versus mechanical alignment in tka: a randomized controlled clinical trial. Clin Orthop Relat Res. 2017;475(1):9-20. doi: https://doi.org/10.1007/s11999-016-4844-x DOI: https://doi.org/10.1007/s11999-016-4844-x
Tian G, Wang L, Liu L, Zhang Y, Zuo L, Li J. Kinematic alignment versus mechanical alignment in total knee arthroplasty: an up-to-date meta-analysis. J Orthop Surg (Hong Kong). 2022;30(3):10225536221125952. doi: https://doi.org/10.1177/10225536221125952 DOI: https://doi.org/10.1177/10225536221125952
Achakri H, Ben-Shlomo Y, Biant L, et al. The National Joint Registry 22nd Annual Report 2025. London: National Joint Registry; 2024 Dec.
Lewis PL, Gill DR, McAuliffe MJ, Stoney JD, Vertullo CJ. Hip, Knee and Shoulder Arthroplasty: 2023 Annual Report. Sydney: Australian Orthopaedic Association; 2025. doi: https://doi.org/10.25310/ywqz9375 DOI: https://doi.org/10.25310/MXFR3061
Guirado M, Saona G, Fernández G. Fondo Nacional de Recursos. Evaluación de artoplastia de rodilla. Año 2021 [Internet]. 2022. Available from: https://www.fnr.gub.uy/publicaciones/informe-de-evaluacion-de-artroplastia-de-rodilla/
Archunan M, Swamy G, Ramasamy A. Stiffness after total knee arthroplasty: prevalence and treatment outcome. Cureus. 2021;13(9):e18271. doi: https://doi.org/10.7759/cureus.18271 DOI: https://doi.org/10.7759/cureus.18271
Mercurio M, Gasparini G, Cofano E, Zappia A, Familiari F, Galasso O. Knee arthrodesis for periprosthetic knee infection: fusion rate, complications, and limb salvage-a systematic review. Healthcare (Basel). 2024;12(7):804. doi: https://doi.org/10.3390/healthcare12070804 DOI: https://doi.org/10.3390/healthcare12070804
Rodríguez-Merchán EC. The stiff total knee arthroplasty: causes, treatment modalities and results. EFORT Open Rev. 2019;4(10):602-610. doi: https://doi.org/10.1302/2058-5241.4.180105 DOI: https://doi.org/10.1302/2058-5241.4.180105
Published
How to Cite
Issue
Section
License
Copyright (c) 2026 Juan Martin Altuna, Juan Miguel Del Castillo Bellón
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
This work is published under a Creative Commons Attribution–NonCommercial–ShareAlike 4.0 International License (CC BY-NC-SA 4.0). The authors retain the copyright.
