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. 2023 Mar;143(3):1549-1569.
doi: 10.1007/s00402-022-04683-z. Epub 2022 Nov 30.

Does stem profile have an impact on the failure patterns in revision total knee arthroplasty?

Alexander Maslaris  1   2 , Eleftherios Tsiridis  3 , Carsten Schoeneberg  4 , Bastian Pass  4 , Georgios Spyrou  4 , Alexandros Maris  5 , Georg Matziolis  6
Affiliations

Does stem profile have an impact on the failure patterns in revision total knee arthroplasty?

Alexander Maslaris et al. Arch Orthop Trauma Surg. 2023 Mar.

Abstract

Introduction: Revision total knee arthroplasty (RTKA) has been increasing continuously. The results of RTKA still remain unsatisfactory. Failure patterns and risk factors in RTKA were thoroughly analyzed, with periprosthetic joint infections (PJI) and aseptic loosening remaining at the forefront of re-revision (ReRTKA) causes. While there is evidence that stem profile impacts the revisability of cemented implants, its association with the modes of RTKA failure is unknown.

Methods: 50 consecutive ReRTKA performed in a single orthopedic center during 2016-2017 were retrospectively analyzed. The cases were stratified according to age, sex, number of preexisting revisions, fixation technique, stem design and causes of re-revision. All explanted implants with conical vs. cylindrical stem profiles were compared.

Results: Mean age was 67 ± 11.5, and 54% were females. 72% of the cases had ≥ 3 previous revisions. 88% were full-cemented, 3% hybrid and 9% press-fit stems. 36% of the RTKA had conical, 58% cylindrical and 6% combined stem profiles. 92% of the RTKA components were removed. Removal causes were: PJI (52.2%), aseptic loosening (34.8%), implant malposition (9.8%), painful knee (1.1%) and instability (2.2%). While the overall RTKA failure patterns were equally distributed between conical and cylindrical stems, subgroup analysis of only cemented ReRTKA revealed a higher incidence of aseptic loosening within cylindrical stem profiles (46.7% vs. 25.7%, P = 0.05).

Conclusion: Stem profile may have an impact on the process of aseptic loosening in cemented non-metaphyseal engaging RTKA, with cylindrical designs tending to worse outcomes than conical designs. Large cohort studies could provide more clarity on current observation.

Keywords: Aseptic loosening; Cemented fixation; Conical stems; Failure pattern; Revision total knee arthroplasty; Stem design; Stem profile.

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Conflict of interest statement

The authors declare that they have no conflict of interest.

Figures

Fig. 1
Fig. 1
a–h Measurements of the conical stem profile of some established RTKA systems using the preoperative planning software MediCAD® orthopedic, German version. Red color: conical part of the stem, green color: cylindrical part of the stem. a ENDO-Model SL cemented (LINK), b MUTARS GenuX cemented (Implantcast), c Enduro cemented (Aesculap), d Columbus cemented (Aesculap), e M.B.T. Revision Tibia Tray cemented (DePuy), f NexGen LCCK cemented (Zimmer), g RT-PLUS Monobloc cemented (Smith & Nephew), h RT-PLUS Modular cemented and cementless (Smith & Nephew). CAVE: Measurements may vary from the original manufacturer’s values
Fig. 2
Fig. 2
a, b Comparison of failure patterns of the RTKA components removed between Co and Cy stem profiles for a all RTKA implants included in the study (cemented and press-fit stems) and b only cemented stems. The values above the bars represent the level of significance as assessed by the Chi square test. *Significance at the 0.05 level
Fig. 3
Fig. 3
a, b Two representative cases of RTKA implants with well-fixed cemented cylindrical femoral stems from an external hospital, which were introduced at our emergencies due to PJI
Fig. 4
Fig. 4
a, b Literature analysis: a process flowchart of the included studies for (left) solely revisions and (right) primary TKA (± revisions), divided according to stem profile (conical vs. cylindrical) and fixation technique of the stem (cemented or cementless). b Summary of overall outcomes separating TKA from RTKA, and Co from Cy stem profiles. Use of cement on stems and metaphyseal fixation (cones/sleeves) are noted in percentage
See this image and copyright information in PMC

References

    1. Robertsson O, W-Dahl A, Lidgren L, Sundberg M (2020) Swedish knee arthroplasty register. Annual Report 2020. Lund. ISBN 978-91-88017-32-1
    1. Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR). Hip, Knee & Shoulder Arthroplasty: Annual Report 2020, Adelaide; AOA, 2020:1-474. ISN 1445-3657. https://aoanjrr.sahmri.com/annual-reports-2020
    1. Finish Arthroplasty Register. ENDOnet 2020. https://www.thl.fi/far/#index
    1. Klug A, Gramlich Y, Rudert M, et al. The projected volume of primary and revision total knee arthroplasty will place an immense burden on future heath care systems over the next 30 years. Knee Surg Sport Traumatol Arthrosc. 2020 doi: 10.1007/s00167-020-06154-7. - DOI - PMC - PubMed
    1. Delanois RE, Mistry JB, Gwam CU, et al. Current epidemiology of revision total knee arthroplasty in the United States. J Arthroplasty. 2017;32:2663–2668. doi: 10.1016/j.arth.2017.03.066. - DOI - PubMed