10-year evolution of day-case hip and knee arthroplasty: a Danish nationwide register study of 166,833 procedures from 2010 to 2020


  • Christian Bredgaard Jensen Department of Orthopaedic Surgery, Clinical Orthopaedic Surgery Hvidovre (CORH), Copenhagen University Hospital Hvidovre, Hvidovre https://orcid.org/0000-0001-6984-6782
  • Anders Troelsen Department of Orthopaedic Surgery, Clinical Orthopaedic Surgery Hvidovre (CORH), Copenhagen University Hospital Hvidovre, Hvidovre https://orcid.org/0000-0003-0132-8182
  • Nicolai Bang Foss Department of Anaesthesiology, Copenhagen University Hospital Hvidovre, Hvidovre
  • Christian Skovgaard Nielsen Department of Orthopaedic Surgery, Clinical Orthopaedic Surgery Hvidovre (CORH), Copenhagen University Hospital Hvidovre, Hvidovre
  • Martin Lindberg-Larsen Department of Orthopaedic Surgery, Orthopaedic Research Unit (ORU), Odense University Hospital, Odense, Denmark https://orcid.org/0000-0002-4483-677X
  • Kirill Gromov Department of Orthopaedic Surgery, Clinical Orthopaedic Surgery Hvidovre (CORH), Copenhagen University Hospital Hvidovre, Hvidovre https://orcid.org/0000-0002-8114-5193




Arthroplasty, Day of surgery discharge, Day-case, Hip, Knee, Outpatient, Same day discharge, Total hip arthroplasty, Total knee arthroplasty, Unicompartmental knee arthroplasty


Background and purpose: No previous studies have investigated the use of day-case arthroplasty in Denmark on a national scale. We investigated the frequency of day-case surgery in total hip (THA), total knee (TKA), and unicompartmental knee arthroplasty (UKA) from 2010 to 2020 in Denmark.
Patients and methods: Primary unilateral THAs, TKAs, and UKAs performed for osteoarthritis were identified in the Danish National Patient Register using procedural and diagnosis codes. Day-case surgery was defined as discharge on the day of surgery. 90-day readmissions were defined as any overnight admissions following discharge.
Results: From 2010 to 2020 Danish surgical centers performed 86,070 THAs, 70,323 TKAs, and 10,440 UKAs. From 2010 to 2014, less than 0.5% of THAs and TKAs were day-case procedures. They increased to 5.4% (95% confidence interval [CI] 4.9–5.8) of THAs and 2.8% (CI 2.4–3.2) of TKAs in 2019. From 2010 to 2014, 11% of UKAs were day-case procedures, but they increased to 20% (CI 18–22) in 2019. This increase was driven by a few surgical centers (3–7 centers). In 2010, readmission rates within 90 days of surgery were 10% after THAs and 11% after TKAs, and 9.4% for both THAs and TKAs in 2019. Readmission rates after UKA fluctuated between 4% and 7%.
Conclusion: From 2010 to 2020 the use of day-case surgery in THA, TKA, and UKA increased in Denmark, driven by only a few centers. During the same period readmissions did not increase.


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Wainwright T W, Kehlet H. Fast-track hip and knee arthroplasty: have we reached the goal? Acta Orthop 2019; 90(1): 3-5. doi: 10.1080/17453674.2018.1550708. DOI: https://doi.org/10.1080/17453674.2018.1550708

Petersen P B, Kehlet H, Jørgensen C C. Improvement in fast-track hip and knee arthroplasty: a prospective multicentre study of 36,935 procedures from 2010 to 2017. Sci Rep 2020; 10(1): 21233. doi: 10.1038/s41598-020-77127-6. DOI: https://doi.org/10.1038/s41598-020-77127-6

Bemelmans Y F L, Keulen M H F, Heymans M, van Haaren E H, Boonen B, Schotanus M G M. Safety and efficacy of outpatient hip and knee arthroplasty: a systematic review with meta-analysis. Arch Orthop Trauma Surg 2022; 142(8): 1775-91. doi: 10.1007/S00402-021-03811-5. DOI: https://doi.org/10.1007/s00402-021-03811-5

Wainwright T W. The current status of daycase hip and knee arthroplasty within the English National Health Service: a retrospective analysis of hospital episode statistics data. Ann R Coll Surg Engl 2021; 103(5): 324-31. doi: 10.1308/RCSANN.2020.7142. DOI: https://doi.org/10.1308/rcsann.2020.7142

Debbi E M, Mosich G M, Bendich I, Kapadia M, Ast M P, Westrich G H. Same-day discharge total hip and knee arthroplasty: trends, complications, and readmission rates. J. Arthroplasty 2022; 37(3): 444-8.e1. doi: 10.1016/J.ARTH.2021.11.023. DOI: https://doi.org/10.1016/j.arth.2021.11.023

Gromov K, Jørgensen C C, Petersen P B, Kjaersgaard-Andersen P, Revald P, Troelsen A, et al. Complications and readmissions following outpatient total hip and knee arthroplasty: a prospective 2-center study with matched controls. Acta Orthop 2019; 90(3): 281-5. doi: 10.1080/17453674.2019.1577049. DOI: https://doi.org/10.1080/17453674.2019.1577049

Gromov K, Kjaersgaard-Andersen P, Revald P, Kehlet H, Husted H. Feasibility of outpatient total hip and knee arthroplasty in unselected patients. Acta Orthop 2017; 88(5): 516-21. doi: 10.1080/17453674.2017.1314158. DOI: https://doi.org/10.1080/17453674.2017.1314158

Schmidt M, Schmidt S A, Sandegaard J L, Ehrenstein V, Pedersen L, Sorensen H T. The Danish National Patient Registry: a review of content, data quality, and research potential. Clin Epidemiol 2015; 7: 449–90. doi: 10.2147/clep.S91125. DOI: https://doi.org/10.2147/CLEP.S91125

Nordic Medico-Statistical Committee (NOMESCO). NOMESCO Classification of Surgical Procedures (NCSP), version 1.16. Available from: http://norden.diva-portal.org/smash/get/diva2:968721/FULLTEXT01.pdf 2011.

Charlson M E, Pompei P, Ales K L, MacKenzie C R. A new method of classifying prognostic comorbidity in longitudinal studies: development and validation. J Chronic Dis 1987; 40(5): 373-83. doi: 10.1016/00219681(87)90171-8. DOI: https://doi.org/10.1016/0021-9681(87)90171-8

Raedkjaer M, Maretty-Kongstad K, Baad-Hansen T, Jørgensen P H, Safwat A, Vedsted P, et al. The impact of comorbidity on mortality in Danish sarcoma patients from 2000–2013: a nationwide population-based multicentre study. PLoS One 2018; 13(6): e0198933. doi: 10.1371/JOURNAL.PONE.0198933. DOI: https://doi.org/10.1371/journal.pone.0198933

Danish Health Data Authority. Afrapportering fra teknikergruppe om opgørelse af indlæggelsesforløb baseret på Landspatientregisteret. https://www.ft.dk/samling/20191/almdel/suu/spm/13/svar/1597313/2088474.pdf.

Laucis N C, Chowdhury M, Dasgupta A, Bhattacharyya T. Trend toward high-volume hospitals and the influence on complications in knee and hip arthroplasty. J Bone Joint Surg Am 2016; 98(9): 707-12. doi: 10.2106/JBJS.15.00399. DOI: https://doi.org/10.2106/JBJS.15.00399

Henkel C, Mikkelsen M, Pedersen A B, Rasmussen L E, Gromov K, Price A, et al. Medial unicompartmental knee arthroplasty: increasingly uniform patient demographics despite differences in surgical volume and usage—a descriptive study of 8,501 cases from the Danish Knee Arthroplasty Registry. Acta Orthop 2019; 90(4): 354-9. doi: 10.1080/17453674.2019.1601834. DOI: https://doi.org/10.1080/17453674.2019.1601834

Podmore B, Hutchings A, Skinner J A, MacGregor A J, Van der Meulen J. Impact of comorbidities on the safety and effectiveness of hip and knee arthroplasty surgery: a national observational study. Bone Joint J 2021; 103(1): 56-64. doi: 10.1302/0301-620X.103B1.BJJ-2020-0859.R1/FORMAT/EPUB. DOI: https://doi.org/10.1302/0301-620X.103B1.BJJ-2020-0859.R1

Jensen C B, Petersen P B, Jørgensen C C, Kehlet H, Troelsen A, Gromov K. Length of stay and 90-day readmission/complication rates in unicompartmental versus total knee arthroplasty: a propensity-score-matched study of 10,494 procedures performed in a fast-track-setup. J Bone Joint Surg Am 2021; 103(12): 1063-71. doi: 10.2106/jbjs.20.01287. DOI: https://doi.org/10.2106/JBJS.20.01287

Kendall M C, Cohen A D, Principe-Marrero S, Sidhom P, Apruzzese P, De Oliveira G. Spinal versus general anesthesia for patients undergoing outpatient total knee arthroplasty: a national propensity matched analysis of early postoperative outcomes. BMC Anesthesiol 2021; 21(1): 226. doi: 10.1186/S12871-021-01442-2. DOI: https://doi.org/10.1186/s12871-021-01442-2

Bovonratwet P, Ondeck N T, Tyagi V, Nelson S J, Rubin L E, Grauer J N. Outpatient and inpatient unicompartmental knee arthroplasty procedures have similar short-term complication profiles. J Arthroplasty 2017; 32(10): 2935-40. doi: 10.1016/j.arth.2017.05.018. DOI: https://doi.org/10.1016/j.arth.2017.05.018

Bradley B, Middleton S, Davis N, Williams M, Stocker M, Hockings M, et al. Discharge on the day of surgery following unicompartmental knee arthroplasty within the United Kingdom NHS. Bone Joint J 2017; 99-b(6): 788-92. doi: 10.1302/0301-620x.99b6.Bjj-2016-0540.R2. DOI: https://doi.org/10.1302/0301-620X.99B6.BJJ-2016-0540.R2

Shah A, Memon M, Kay J, Wood T J, Tushinski D M, Khanna V. Preoperative patient factors affecting length of stay following total knee arthroplasty: a systematic review and meta-analysis. J Arthroplasty 2019; 34(9): 2124-65.e1. doi: 10.1016/j.arth.2019.04.048. DOI: https://doi.org/10.1016/j.arth.2019.04.048

DeMik D E, Carender C N, Glass N A, Callaghan J J, Bedard N A. More patients are being discharged home after total knee arthroplasty, however rates vary between large databases. J Arthroplasty 2021; 36(1): 173-9. doi: 10.1016/J.ARTH.2020.07.059. DOI: https://doi.org/10.1016/j.arth.2020.07.059

Pitter F T, Jørgensen C C, Lindberg-Larsen M, Kehlet H. Postoperative morbidity and discharge destinations after fast-track hip and knee arthroplasty in patients older than 85 years. Anesth Analg 2016; 122(6): 1807-15. doi: 10.1213/ane.0000000000001190. DOI: https://doi.org/10.1213/ANE.0000000000001190

Hamilton T W, Pandit H G, Jenkins C, Mellon S J, Dodd C A F, Murray D W. Evidence-based indications for mobile-bearing unicompartmental knee arthroplasty in a consecutive cohort of thousand knees. J Arthroplasty 2017; 32(6): 1779-85. doi: 10.1016/j.arth.2016.12.036. DOI: https://doi.org/10.1016/j.arth.2016.12.036

Ramaswamy A, Marchese M, Cole A P, Harmouch S, Friedlander D, Weissman J S, et al. Comparison of hospital readmission after total hip and total knee arthroplasty vs spinal surgery after implementation of the Hospital Readmissions Reduction Program. JAMA Netw Open 2019; 2(5): e194634. doi: 10.1001/JAMANETWORKOPEN.2019.4634. DOI: https://doi.org/10.1001/jamanetworkopen.2019.4634

Harris I A, Hatton A, de Steiger R, Lewis P, Graves S, Wales S, et al. Declining early mortality after hip and knee arthroplasty. ANZ J Surg 2020; 90(1-2): 119-22. doi: 10.1111/ANS.15529. DOI: https://doi.org/10.1111/ans.15529

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How to Cite

Jensen, C. B., Troelsen, A., Foss, N. B., Nielsen, C. S., Lindberg-Larsen, M., & Gromov, K. (2023). 10-year evolution of day-case hip and knee arthroplasty: a Danish nationwide register study of 166,833 procedures from 2010 to 2020. Acta Orthopaedica, 94, 178–184. https://doi.org/10.2340/17453674.2023.11961





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