Superstition in arthroplasty: does a suspicious size or surgery date have a higher revision rate? A Dutch arthroplasty register study
DOI:
https://doi.org/10.2340/17453674.2025.44594Keywords:
Arthroplasty, Friday thirteenth, Hip, Knee, SuperstitionAbstract
Background and purpose: There are still strong beliefs in medicine concerning things that bring “bad luck.” It is unclear whether a suspicious component size or surgery date is related to “bad luck” in orthopedic surgery. We aimed to examine: (i) if a potentially unlucky femoral stem size 13 in total hip arthroplasty (THA), and (ii) if a possible unlucky surgery date, Friday 13th, in THA and total knee arthroplasty (TKA) have a higher revision rate.
Methods: We analyzed 611,050 THAs and TKAs, performed in the past 13 years using Dutch Arthroplasty Register data. The revision rate of uncemented femoral stem size 13 (Corail and Taperloc) in THA was compared with all other stem sizes of the same type. Furthermore, the revision rate of THA and TKA implanted on Friday 13th was compared with all other days and with other Fridays. Both were performed using competing risk analyses with death as competing risk and cause-specific multivariable Cox proportional hazard regression analyses.
Results: The use of an uncemented Corail or Taperloc femoral stem size 13 in THA was associated with a lower revision rate (3.0%, 95% confidence interval [CI] 2.3–4.0) compared with the revision rate of other femoral stem sizes (3.5%, CI 3.3–3.8) (hazard ratio [HR] 0.76, CI 0.65–0.87). TKA procedures on Friday 13th were not associated with increased revision rate (5.2%, CI 4.1–6.7) compared with procedures on other days (6.0%, CI 5.9–6.2) or on other Fridays (5.8%, CI 5.4–6.2) (HR 1.03, CI 0.80–1.32 and HR 1.01, CI 0.79–1.30, respectively). For THA, procedures on Friday 13th were associated with a higher revision rate (5.1%, CI 3.9–6.6) compared with procedures on other days (4.6%, CI 4.5-4.8) (HR 1.32, CI 1.04–1.67) but not compared with procedures on other Fridays (4.8%, CI 4.4–5.1) (HR 1.24, CI 0.97–1.58).
Conclusion: Based on national arthroplasty registry data, femoral stem size 13 in THA was associated with a lower revision rate. TKA procedures on Friday 13th were not associated with increased revision rate; however, in THA there seems to be an increased risk of revision in THA procedures performed on Friday 13th compared with other days, but not when compared with other Fridays.
Downloads
References
Uwayezu D, Ntigura E, Gatarayiha A, Erem A S, Haque M, Majumder M A A, et al. Conflict between science and superstition in medical practices. Intl Med Educ 2022; 1: 33-42. DOI: https://doi.org/10.3390/ime1020007
Husted H, Gromov K, Malchau H, Freiberg A, Gebuhr P, Troelsen A. Traditions and myths in hip and knee arthroplasty. Acta Orthop 2014; 85: 548-55. doi: 10.3109/17453674.2014.971661. DOI: https://doi.org/10.3109/17453674.2014.971661
Exadaktylos A K, Sclabas G, Siegenthaler A, Eggli S, Kohler H P, Luterbacher J. Friday the 13th and full-moon: the “worst case scenario” or only superstition? Am J Emerg Med 2001; 19: 319-20. doi: 10.1053/ajem.2001.24488. DOI: https://doi.org/10.1053/ajem.2001.24488
Singh Dubb S, Ferro A, Fowell C. “Shh-don’t say the Q-word” or do you? Br J Oral Maxillofac Surg 2021; 59: e13-e16. doi: 10.1016/j.bjoms.2020.08.044. DOI: https://doi.org/10.1016/j.bjoms.2020.08.044
Chiu S L, Gee M J, Muo C H, Chu C L, Lan S J, Chen C L. The sociocultural effects on orthopedic surgeries in Taiwan. PLoS One 2018; 13: e0195183. doi: 10.1371/journal.pone.0195183. DOI: https://doi.org/10.1371/journal.pone.0195183
Mjaess G, Aoun F, Kazzi H, Karam A, Albisinni S, Roumeguere T. Myths, superstitions, and popular beliefs: do they still impact our practice? Ann Surg 2021; 274: e641-e642. doi: 10.1097/SLA.0000000000005202. DOI: https://doi.org/10.1097/SLA.0000000000005202
Ficklscherer A, Angermann A, Weber P, Wegener B, Pietschmann M, Muller P. Lunar phase does not influence perioperative complications in total hip arthroplasty. Arch Med Sci 2012; 8: 111-14. doi: 10.5114/aoms.2012.27290. DOI: https://doi.org/10.5114/aoms.2012.27290
Nardelli P, Giesinger J, Liebensteiner M, Pagenstert G, Neururer S, Leitner H, et al. Moonlight surgery: no influence of moon phase or Friday 13th on outcomes of total knee arthroplasty. Arch Orthop Trauma Surg 2023; 143: 6169-75. doi: 10.1007/s00402-023-04919-6. DOI: https://doi.org/10.1007/s00402-023-04919-6
Scanlon T J, Luben R N, Scanlon F L, Singleton N. Is Friday the 13th bad for your health? BMJ 1993; 307: 1584-6. doi: 10.1136/bmj.307.6919.1584. DOI: https://doi.org/10.1136/bmj.307.6919.1584
Schuld J, Slotta J E, Schuld S, Kollmar O, Schilling M K, Richter S. Popular belief meets surgical reality: impact of lunar phases, Friday the 13th and zodiac signs on emergency operations and intraoperative blood loss. World J Surg 2011; 35: 1945-9. doi: 10.1007/s00268-011-1166-8. DOI: https://doi.org/10.1007/s00268-011-1166-8
Lo B M, Visintainer C M, Best H A, Beydoun H A. Answering the myth: use of emergency services on Friday the 13th. Am J Emerg Med 2012; 30: 886-9. doi: 10.1016/j.ajem.2011.06.008. DOI: https://doi.org/10.1016/j.ajem.2011.06.008
Ranganathan S, Riveros C, Geng M, Chang C, Tsugawa Y, Ravi B, et al. Superstition in surgery: a population-based cohort study to assess the association between surgery on Friday the 13th and postoperative outcomes. Ann Surg Open 2024; 5: e375. doi: 10.1097/AS9.0000000000000375. DOI: https://doi.org/10.1097/AS9.0000000000000375
van Steenbergen LN, Denissen G A, Spooren A, van Rooden S M, van Oosterhout F J, Morrenhof J W, et al. More than 95% completeness of reported procedures in the population-based Dutch Arthroplasty Register. Acta Orthop 2015; 86: 498-505. doi: 10.3109/17453674.2015.1028307. DOI: https://doi.org/10.3109/17453674.2015.1028307
Ranstam J, Kärrholm J, Pulkkinen P, Makela K, Espehaug B, Pedersen A B, et al. Statistical analysis of arthroplasty data. I. Introduction and background. Acta Orthop 2011; 82: 253-7. doi: 10.3109/17453674.2011.588862. DOI: https://doi.org/10.3109/17453674.2011.588862
Ranstam J, Kärrholm J, Pulkkinen P, Makela K, Espehaug B, Pedersen A B, et al. Statistical analysis of arthroplasty data. II. Guidelines. Acta Orthop 2011; 82: 258-67. doi: 10.3109/17453674.2011.588863. DOI: https://doi.org/10.3109/17453674.2011.588863
Schemper M, Smith T L. A note on quantifying follow-up in studies of failure time. Control Clin Trials 1996; 17: 343-6. doi: 10.1016/0197-2456(96)00075-x. DOI: https://doi.org/10.1016/0197-2456(96)00075-X
Anneberg M, Troelsen A, Gundtoft P, Pedersen A B. Association of socioeconomic inequality and risk of periprosthetic joint infection after total knee arthroplasty: a Danish cohort study of 75,141 cases. Acta Orthop 2025; 96: 371-379. doi: 10.2340/17453674.2025.43678. DOI: https://doi.org/10.2340/17453674.2025.43678
Additional Files
Published
How to Cite
License
Copyright (c) 2025 Jeroen C van Egmond, Jantsje H Pasma, Liza N van Steenbergen, Olav P van der Jagt

This work is licensed under a Creative Commons Attribution 4.0 International License.
