{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T04:51:08Z","timestamp":1787028668259,"version":"build-2736575974"},"reference-count":44,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T00:00:00Z","timestamp":1783987200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Purpose: Sarcopenia has emerged as a potential prognostic factor for postoperative complications, functional recovery, patient-reported outcomes, and healthcare costs in patients undergoing total knee arthroplasty (TKA). This systematic review aimed to evaluate its impact on these outcomes following primary TKA. Methods: A systematic review was conducted according to PRISMA guidelines and prospectively registered in PROSPERO (CRD420261320013). PubMed\/MEDLINE, EMBASE, and Cochrane Library were searched up to 1 December 2025. Comparative clinical studies including sarcopenic and non-sarcopenic patients undergoing primary TKA and reporting postoperative outcomes were included. Methodological quality was assessed using the MINORS tool. Due to heterogeneity in study design, diagnostic criteria, and outcome measures, a narrative synthesis was performed. Results: Nine studies including more than 93,000 patients were analyzed. Sarcopenia prevalence ranged from 7.7% to 25%. Sarcopenic patients demonstrated higher rates of postoperative complications, including medical events, blood transfusion, falls, fractures, reoperations, and implant-related complications. Functional recovery was delayed, particularly in patients with sarcopenic obesity, with slower improvements in range of motion and gait speed. Although both groups improved after TKA, short- to mid-term patient-reported outcomes were often inferior in sarcopenic patients, while long-term differences were less consistent. Sarcopenia was also associated with longer hospital stay and increased healthcare costs. Conclusions: Sarcopenia is associated with worse postoperative outcomes following primary TKA and may represent a modifiable risk factor for perioperative optimization.<\/jats:p>","DOI":"10.3390\/jcm15145523","type":"journal-article","created":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T01:05:58Z","timestamp":1784077558000},"page":"5523","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Sarcopenia and Postoperative Outcomes Following Total Knee Arthroplasty: A Systematic Review of Observational Studies"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-4972-5677","authenticated-orcid":false,"given":"Pierangelo","family":"Za","sequence":"first","affiliation":[{"name":"IRCCS Ospedale San Raffaele, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6342-2740","authenticated-orcid":false,"given":"Marco","family":"Minelli","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, Pieve Emanuele, 20072 Milan, Italy"},{"name":"IRCCS Humanitas Research Hospital, Via Manzoni 56, Rozzano, 20089 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Carlo","family":"Esposito","sequence":"additional","affiliation":[{"name":"IRCCS Ospedale San Raffaele, 20132 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-7792-2336","authenticated-orcid":false,"given":"Vincenzo","family":"Longobardi","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences, Humanitas University, Via Rita Levi Montalcini 4, Pieve Emanuele, 20072 Milan, Italy"},{"name":"IRCCS Humanitas Research Hospital, Via Manzoni 56, Rozzano, 20089 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sebastiano","family":"Vasta","sequence":"additional","affiliation":[{"name":"Department of Movement, Human and Health Sciences, Foro Italico University of Rome, 00135 Rome, Italy"},{"name":"Operative Research Unit of Orthopaedic and Trauma Surgery, Fondazione Policlinico Universitario Campus Bio-Medico, Via \u00c1lvaro del Portillo, 00128 Rome, Italy"},{"name":"Research Unit of Orthopaedic and Trauma Surgery, Department of Medicine and Surgery, Universit\u00e0 Campus Bio-Medico di Roma, Via \u00c1lvaro del Portillo, 00128 Rome, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giuseppe","family":"Calafiore","sequence":"additional","affiliation":[{"name":"IRCCS Humanitas Research Hospital, Via Manzoni 56, Rozzano, 20089 Milan, Italy"},{"name":"Department of Orthopaedic and Trauma Surgery, Citt\u00e0 di Parma Clinic, Piazzale Athos Maestri 5, 43123 Parma, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Federico","family":"Della Rocca","sequence":"additional","affiliation":[{"name":"IRCCS Humanitas Research Hospital, Via Manzoni 56, Rozzano, 20089 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,14]]},"reference":[{"key":"ref_1","first-page":"127","article-title":"Defining sarcopenia: Some caveats and challenges","volume":"23","author":"Marco","year":"2020","journal-title":"Curr. Opin. Clin. Nutr. Metab. Care"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2636","DOI":"10.1016\/S0140-6736(19)31138-9","article-title":"Sarcopenia","volume":"393","author":"Sayer","year":"2019","journal-title":"Lancet"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"16","DOI":"10.1093\/ageing\/afy169","article-title":"Sarcopenia: Revised European consensus on definition and diagnosis","volume":"48","author":"Bahat","year":"2019","journal-title":"Age Ageing"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"536","DOI":"10.1016\/j.jjcc.2015.11.011","article-title":"Predictors of surgery-induced muscle proteolysis in patients undergoing cardiac surgery","volume":"68","author":"Iida","year":"2016","journal-title":"J. Cardiol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1","DOI":"10.5534\/wjmh.200190","article-title":"Rehabilitation Nutrition and Exercise Therapy for Sarcopenia","volume":"40","author":"Kakehi","year":"2022","journal-title":"World J. Men\u2019s Health"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"2197","DOI":"10.1016\/S0140-6736(12)61689-4","article-title":"Disability-adjusted life years (DALYs) for 291 diseases and injuries in 21 regions, 1990\u20132010: A systematic analysis for the Global Burden of Disease Study 2010","volume":"380","author":"Murray","year":"2012","journal-title":"Lancet"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Nishikawa, H., Asai, A., Fukunishi, S., Nishiguchi, S., and Higuchi, K. (2021). Metabolic Syndrome and Sarcopenia. Nutrients, 13.","DOI":"10.3390\/nu13103519"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"748","DOI":"10.1093\/ageing\/afu115","article-title":"Prevalence of and interventions for sarcopenia in ageing adults: A systematic review. Report of the International Sarcopenia Initiative (EWGSOP and IWGS)","volume":"43","author":"Landi","year":"2014","journal-title":"Age Ageing"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"3873","DOI":"10.1002\/ksa.12804","article-title":"Arthrogenic muscle inhibition: A prevalent issue in knee arthroplasty","volume":"33","author":"Parratte","year":"2025","journal-title":"Knee Surg. Sports Traumatol. Arthrosc."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Pegreffi, F., Balestra, A., De Lucia, O., Smith, L., Barbagallo, M., and Veronese, N. (2023). Prevalence of Sarcopenia in Knee Osteoarthritis: A Systematic Review and Meta-Analysis. J. Clin. Med., 12.","DOI":"10.3390\/jcm12041532"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"3128","DOI":"10.1016\/j.arth.2024.06.021","article-title":"Prevalence and Clinical Impact of Sarcopenia in Patients Undergoing Total Joint Arthroplasty: A Systematic Review and a Meta-Analysis","volume":"39","author":"Sumbal","year":"2024","journal-title":"J. Arthroplasty"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"327","DOI":"10.1186\/s40001-023-01322-0","article-title":"Causal relationship between sarcopenia and osteoarthritis: A bi-directional two-sample mendelian randomized study","volume":"28","author":"Yang","year":"2023","journal-title":"Eur. J. Med. Res."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"250","DOI":"10.1016\/j.semarthrit.2009.10.001","article-title":"Quadriceps Arthrogenic Muscle Inhibition: Neural Mechanisms and Treatment Perspectives","volume":"40","author":"Rice","year":"2010","journal-title":"Semin. Arthritis Rheum."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1121","DOI":"10.1016\/j.clnu.2017.08.016","article-title":"Does nutrition play a role in the prevention and management of sarcopenia?","volume":"37","author":"Robinson","year":"2018","journal-title":"Clin. Nutr."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"176","DOI":"10.1016\/j.jor.2025.04.015","article-title":"Sarcopenia in total joint Arthroplasty: Risk factor for poor postoperative outcomes and higher costs of care","volume":"69","author":"Zaronias","year":"2025","journal-title":"J. Orthop."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Ta\u015fc\u0131, M., \u00d6zer, M., and \u00c7amur, S. (2025). Recognizing Sarcopenia in Total Knee Arthroplasty Patients: A Call for Greater Awareness. J. Arthroplasty, in press.","DOI":"10.1016\/j.arth.2025.12.011"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Shon, O.-J., Kim, G.B., and Cho, S.J. (2023). Does Sarcopenia Accompanying End-Stage Knee Osteoarthritis Affect the Outcomes following Total Knee Arthroplasty?. Medicina, 59.","DOI":"10.3390\/medicina59061078"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"594","DOI":"10.1016\/j.arth.2022.10.011","article-title":"Are 20% of Patients Actually Dissatisfied Following Total Knee Arthroplasty? A Systematic Review of the Literature","volume":"38","author":"DeFrance","year":"2023","journal-title":"J. Arthroplasty"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"b2535","DOI":"10.1136\/bmj.b2535","article-title":"Preferred reporting items for systematic reviews and meta-analyses: The PRISMA statement","volume":"339","author":"Moher","year":"2009","journal-title":"BMJ"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"420","DOI":"10.5195\/jmla.2018.345","article-title":"The impact of patient, intervention, comparison, outcome (PICO) as a search strategy tool on literature search quality: A systematic review","volume":"106","author":"Eriksen","year":"2018","journal-title":"J. Med. Libr. Assoc."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"128","DOI":"10.1055\/s-0040-1713355","article-title":"Comparative analysis on the effects of sarcopenia following primary total knee arthroplasty: A retrospective matched-control analysis","volume":"35","author":"Ardeljan","year":"2022","journal-title":"J. Knee Surg."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Liao, C.-D., Huang, S.-W., Huang, Y.-Y., and Lin, C.-L. (2021). Effects of Sarcopenic Obesity and Its Confounders on Knee Range of Motion Outcome after Total Knee Replacement in Older Adults with Knee Osteoarthritis: A Retrospective Study. Nutrients, 13.","DOI":"10.3390\/nu13113817"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"631","DOI":"10.1016\/j.jamda.2022.01.056","article-title":"Impact of sarcopenia and obesity on gait speed after total knee replacement","volume":"23","author":"Liao","year":"2022","journal-title":"J. Am. Med. Dir. Assoc."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1759720X21998508","DOI":"10.1177\/1759720X21998508","article-title":"Impact of sarcopenia on rehabilitation outcomes after total knee replacement in older adults with knee osteoarthritis","volume":"13","author":"Liao","year":"2021","journal-title":"Ther. Adv. Musculoskelet. Dis."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Ho, K.K., Lau, L.C., Chau, W.W., Poon, Q., Chung, K.Y., and Wong, R.M. (2021). End-stage knee osteoarthritis with and without sarcopenia and the effect of knee arthroplasty\u2014A prospective cohort study. BMC Geriatr., 21.","DOI":"10.1186\/s12877-020-01929-6"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Hwang, D., Han, H.S., Lee, M.C., and Ro, D.H. (2022). Low muscle mass is an independent risk factor for postoperative blood transfusion in total knee arthroplasty: A retrospective, propensity score-matched cohort study. BMC Geriatr., 22.","DOI":"10.1186\/s12877-022-02903-0"},{"key":"ref_27","doi-asserted-by":"crossref","unstructured":"Tzartza, C.L., Karapalis, N., Voulgaridou, G., Zidrou, C., Beletsiotis, A., Chatziprodromidou, I.P., Giaginis, C., and Papadopoulou, S.K. (2023). Comparative analysis on the effect of sarcopenia in patients with knee osteoarthritis before and after total knee arthroplasty. Diseases, 11.","DOI":"10.3390\/diseases11010036"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1160","DOI":"10.1111\/os.14053","article-title":"The Negative Impacts of Sarcopenia on Primary Total Knee Arthroplasty under the Enhanced Recovery after Surgery Protocol","volume":"16","author":"Zhou","year":"2024","journal-title":"Orthop. Surg."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"4238","DOI":"10.1097\/JS9.0000000000000688","article-title":"Impact of sarcopenia on outcomes in surgical patients: A systematic review and meta-analysis","volume":"109","author":"Knoedler","year":"2023","journal-title":"Int. J. Surg."},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Zhang, X.Y., Zhou, X., Han, J.C., Wu, S., Zhang, X.Q., Cui, Q.T., Huang, P.T., Cai, Y.Y., Zhang, C., and Liu, A.F. (2025). Impact of sarcopenia on clinical outcomes of older adults undergoing total knee arthroplasty for osteoarthritis: A systematic review and meta-analysis. BMC Musculoskelet. Disord., 26.","DOI":"10.1186\/s12891-025-09245-z"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"1185","DOI":"10.1016\/j.jamda.2023.04.005","article-title":"Combinations of Sarcopenia Diagnostic Criteria by Asian Working Group of Sarcopenia (AWGS) 2019 Guideline and Incident Adverse Health Outcomes in Community-Dwelling Older Adults","volume":"24","author":"Oh","year":"2023","journal-title":"J. Am. Med. Dir. Assoc."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"547","DOI":"10.1093\/gerona\/glu010","article-title":"The FNIH sarcopenia project: Rationale, study description, conference recommendations, and final estimates","volume":"69","author":"Studenski","year":"2014","journal-title":"J. Gerontol. A Biol. Sci. Med. Sci."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"e146","DOI":"10.3346\/jkms.2022.37.e146","article-title":"A Review of Sarcopenia Pathophysiology, Diagnosis, Treatment and Future Direction","volume":"37","author":"Cho","year":"2022","journal-title":"J. Korean Med. Sci."},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Dalle, S., Rossmeislova, L., and Koppo, K. (2017). The Role of Inflammation in Age-Related Sarcopenia. Front. Physiol., 8.","DOI":"10.3389\/fphys.2017.01045"},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Wang, H., and Lin, P. (2024). Association between sarcopenia and hemoglobin level: A systematic review and meta-analysis. Front. Med., 11.","DOI":"10.3389\/fmed.2024.1424227"},{"key":"ref_36","doi-asserted-by":"crossref","unstructured":"Hung, M., Jensen, A., Strickler, I., Vu, S., Hon, E.S., Arapovic, A., and El-Othmani, M.M. (2026). Frailty and Sarcopenia as Predictors of Functional Recovery After Total Hip and Knee Arthroplasty: A Narrative Review. J. Clin. Med., 15.","DOI":"10.3390\/jcm15103578"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"pzac033","DOI":"10.1093\/ptj\/pzac033","article-title":"Total Knee Arthroplasty Assessments Should Include Strength and Performance-Based Functional Tests to Complement Range-of-Motion and Patient-Reported Outcome Measures","volume":"102","author":"Capin","year":"2022","journal-title":"Phys. Ther."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"938","DOI":"10.1002\/ejsc.12114","article-title":"Resistance exercise training to improve post-operative rehabilitation in knee arthroplasty patients: A narrative review","volume":"24","author":"Monsegue","year":"2024","journal-title":"Eur. J. Sport. Sci."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"102758","DOI":"10.1016\/j.otsr.2020.102758","article-title":"The ceiling effects of patient reported outcome measures for total knee arthroplasty","volume":"107","author":"Eckhard","year":"2021","journal-title":"Orthop. Traumatol. Surg. Res."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"86","DOI":"10.1002\/jcsm.12783","article-title":"Global prevalence of sarcopenia and severe sarcopenia: A systematic review and meta-analysis","volume":"13","author":"Balntzi","year":"2022","journal-title":"J. Cachexia Sarcopenia Muscle"},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Pegreffi, F., Chiaramonte, R., Donati Zeppa, S., Lauretani, F., Salvi, M., Zucchini, I., Veronese, N., Vecchio, M., Bartolacci, A., and Stocchi, V. (2024). Optimizing the Preoperative Preparation of Sarcopenic Older People: The Role of Prehabilitation and Nutritional Supplementation before Knee Arthroplasty. Nutrients, 16.","DOI":"10.3390\/nu16203462"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"e2024030","DOI":"10.4178\/epih.e2024030","article-title":"The effectiveness of protein supplementation combined with resistance exercise programs among community-dwelling older adults with sarcopenia: A systematic review and meta-analysis","volume":"46","author":"Whaikid","year":"2024","journal-title":"Epidemiol. Health"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1097\/PHM.0000000000002006","article-title":"Prehabilitation for Total Knee or Total Hip Arthroplasty: A Systematic Review","volume":"102","author":"Konnyu","year":"2023","journal-title":"Am. J. Phys. Med. Rehabil."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"300","DOI":"10.1016\/j.jamda.2019.12.012","article-title":"Asian Working Group for Sarcopenia: 2019 Consensus Update on Sarcopenia Diagnosis and Treatment","volume":"21","author":"Chen","year":"2020","journal-title":"J. Am. Med. Dir. Assoc."}],"container-title":["Journal of Clinical Medicine"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/14\/5523\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T01:20:09Z","timestamp":1784078409000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2077-0383\/15\/14\/5523"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,7,14]]},"references-count":44,"journal-issue":{"issue":"14","published-online":{"date-parts":[[2026,7]]}},"alternative-id":["jcm15145523"],"URL":"https:\/\/doi.org\/10.3390\/jcm15145523","relation":{},"ISSN":["2077-0383"],"issn-type":[{"value":"2077-0383","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,7,14]]}}}