Alignment in Medial Fixed-Bearing Unicompartmental Knee Arthroplasty: The Limb Has a Leg Up on the Component

Published:August 19, 2021DOI:https://doi.org/10.1016/j.arth.2021.08.015

      Abstract

      Background

      To assess how implant alignment affects unicompartmental knee arthroplasty (UKA) outcome, we compared tibial component alignment of well-functioning UKAs against 2 groups of failed UKAs, revised for progression of lateral compartment arthritis (“Progression”) and aseptic loosening (“Loosening”).

      Methods

      We identified 37 revisions for Progression and 61 revisions for Loosening from our prospective institutional database of 3351 medial fixed-bearing UKAs performed since 2000. Revision cohorts were matched on age, gender, body mass index, and postoperative range of motion with “Successful” unrevised UKAs with minimum 10-year follow-up and Knee Society Score ≥70. Tibial component coronal (TCA) and sagittal (TSA) plane alignment was measured on postoperative radiographs. Limb alignment was quantified by hip-knee-ankle (HKA) angle on long-leg radiographs. In addition to directly comparing groups, a multivariate logistic regression examined how limb and component alignments were associated with UKA revision.

      Results

      In the Progression group, component alignment was similar to the matched successes (TCA 3.6° ± 3.5° varus vs 5.1° ± 3.5° varus, P = .07; TSA 8.4° ± 4.4° vs 8.8° ± 3.6°, P = .67), whereas HKA angle was significantly more valgus (0.3° ± 3.6° valgus vs 4.4° ± 2.6° varus, P < .001). Loosening group component alignment was also similar to the matched successes (TCA 6.1° ± 3.7° varus vs 5.9° ± 3.1° varus, P = .72; TSA 8.4° ± 4.6° vs 8.1° ± 3.9°, P = .68), and HKA was significantly more varus (6.1° ± 3.1° varus vs 4.0° ± 2.7° varus, P < .001). Using a multivariate logistic regression, HKA angle was the most significant factor associated with revision (P < .001).

      Conclusion

      In this population of revised UKAs and long-term successes, limb alignment was a more important determinant of outcome than tibial component alignment.

      Level of Evidence

      Level III case-control study.

      Keywords

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      References

        • Collier M.B.
        • Eickmann T.H.
        • Sukezaki F.
        • McAuley J.P.
        • Engh G.A.
        Patient, implant, and alignment factors associated with revision of medial compartment unicondylar arthroplasty.
        J Arthroplasty. 2006; 21: 108-115
        • Hamilton W.G.
        • Ammeen D.
        • Engh Jr., C.A.
        • Engh G.A.
        Learning curve with minimally invasive unicompartmental knee arthroplasty.
        J Arthroplasty. 2010; 25: 735-740
        • Hernigou P.
        • Deschamps G.
        Posterior slope of the tibial implant and the outcome of unicompartmental knee arthroplasty.
        J Bone Joint Surg Am. 2004; 86: 506-511
        • Aleto T.J.
        • Berend M.E.
        • Ritter M.A.
        • Faris P.M.
        • Meneghini R.M.
        Early failure of unicompartmental knee arthroplasty leading to revision.
        J Arthroplasty. 2008; 23: 159-163
        • Chatellard R.
        • Sauleau V.
        • Colmar M.
        • Robert H.
        • Raynaud G.
        • Brilhault J.
        • et al.
        Medial unicompartmental knee arthroplasty: does tibial component position influence clinical outcomes and arthroplasty survival?.
        Orthop Traumatol Surg Res. 2013; 99: S219-S225
        • Kazarian G.S.
        • Barrack T.N.
        • Okafor L.
        • Barrack R.L.
        • Nunley R.M.
        • Lawrie C.M.
        High prevalence of radiographic outliers and revisions with unicompartmental knee arthroplasty.
        J Bone Joint Surg Am. 2020; 102: 1151-1159
        • Slaven S.E.
        • Cody J.P.
        • Sershon R.A.
        • Ho H.
        • Hopper Jr., R.H.
        • Fricka K.B.
        The impact of coronal alignment on revision in medial fixed-bearing unicompartmental knee arthroplasty.
        J Arthroplasty. 2020; 35: 353-357
        • Citak M.
        • Suero E.M.
        • Citak M.
        • Dunbar N.J.
        • Branch S.H.
        • Conditt M.A.
        • et al.
        Unicompartmental knee arthroplasty: is robotic technology more accurate than conventional technique?.
        Knee. 2013; 20: 268-271
        • Lonner J.H.
        • John T.K.
        • Conditt M.A.
        Robotic arm-assisted UKA improves tibial component alignment: a pilot study.
        Clin Orthop Relat Res. 2010; 468: 141-146
        • Bell S.W.
        • Anthony I.
        • Jones B.
        • MacLean A.
        • Rowe P.
        • Blyth M.
        Improved accuracy of component positioning with robotic-assisted unicompartmental knee arthroplasty: data from a prospective, randomized controlled study.
        J Bone Joint Surg Am. 2016; 98: 627-635
        • Batailler C.
        • White N.
        • Ranaldi F.M.
        • Neyret P.
        • Servien E.
        • Lustig S.
        Improved implant position and lower revision rate with robotic-assisted unicompartmental knee arthroplasty.
        Knee Surg Sports Traumatol Arthrosc. 2019; 27: 1232-1240
        • Rostoker W.
        • Galante J.O.
        Contact pressure dependence of wear rates of ultra high molecular weight polyethylene.
        J Biomed Mater Res. 1979; 13: 957-964
        • Wasielewski R.C.
        • Galante J.O.
        • Leighty R.M.
        • Natarajan R.N.
        • Rosenberg A.G.
        Wear patterns on retrieved polyethylene tibial inserts and their relationship to technical considerations during total knee arthroplasty.
        Clin Orthop Relat Res. 1994; 299: 31-43
        • Eickmann T.H.
        • Collier M.B.
        • Sukezaki F.
        • McAuley J.P.
        • Engh G.A.
        Survival of medial unicondylar arthroplasties placed by one surgeon 1984-1998.
        Clin Orthop Relat Res. 2006; 452: 143-149
        • Dyrhovden G.S.
        • Lygre S.H.L.
        • Badawy M.
        • Gøthesen Ø.
        • Furnes O.
        Have the sauses of revision for total and unicompartmental knee arthroplasties changed during the past two decades?.
        Clin Orthop Relat Res. 2017; 475: 1874-1886
        • Epinette J.A.
        • Brunschweiler B.
        • Mertl P.
        • Mole D.
        • Cazenave A.
        • French Society for Hip and Knee
        Unicompartmental knee arthroplasty modes of failure: wear is not the main reason for failure: a multicentre study of 418 failed knees.
        Orthop Traumatol Surg Res. 2012; 98: S124-S130
        • van der List J.P.
        • Zuiderbaan H.A.
        • Pearle A.D.
        Why do medial unicompartmental knee arthroplasties fail today?.
        J Arthroplasty. 2016; 31: 1016-1021
        • Moreland J.R.
        • Bassett L.W.
        • Hanker G.J.
        Radiographic analysis of the axial alignment of the lower extremity.
        J Bone Joint Surg Am. 1987; 69: 745-749
        • Bush A.N.
        • Ziemba-Davis M.
        • Deckard E.R.
        • Meneghini R.M.
        An experienced surgeon can meet or exceed robotic accuracy in manual unicompartmental knee arthroplasty.
        J Bone Joint Surg Am. 2019; 101: 1479-1484
        • Skyttä E.T.
        • Lohman M.
        • Tallroth K.
        • Remes V.
        Comparison of standard anteroposterior knee and hip-to-ankle radiographs in determining the lower limb and implant alignment after total knee arthroplasty.
        Scand J Surg. 2009; 98: 250-253
        • Tammachote N.
        • Kriengburapha N.
        • Chaiwuttisak A.
        • Kanitnate S.
        • Boontanapibul K.
        Is regular knee radiograph reliable enough to assess the knee prosthesis position?.
        J Arthroplasty. 2018; 33: 3038-3042
        • Cartier P.
        • Sanouiller J.L.
        • Grelsamer R.P.
        Unicompartmental knee arthroplasty surgery. 10-year minimum follow-up period.
        J Arthroplasty. 1996; 11: 782-788
        • Naudie D.
        • Guerin J.
        • Parker D.A.
        • Bourne R.B.
        • Rorabeck C.H.
        Medial unicompartmental knee arthroplasty with the Miller-Galante prosthesis.
        J Bone Joint Surg Am. 2004; 86: 1931-1935
        • Berger R.A.
        • Meneghini R.M.
        • Jacobs J.J.
        • Sheinkop M.B.
        • Della Valle C.J.
        • Rosenberg A.G.
        • et al.
        Results of unicompartmental knee arthroplasty at a minimum of ten years of follow-up.
        J Bone Joint Surg Am. 2005; 87: 999-1006
        • Jennings J.M.
        • Kleeman-Forsthuber L.T.
        • Bolognesi M.P.
        Medial unicompartmental arthroplasty of the knee.
        J Am Acad Orthop Surg. 2019; 27: 166-176
        • Diezi C.
        • Wirth S.
        • Meyer D.C.
        • Koch P.P.
        Effect of femoral to tibial varus mismatch on the contact area of unicondylar knee prostheses.
        Knee. 2010; 17: 350-355
        • Innocenti B.
        • Pianigiani S.
        • Ramundo G.
        • Thienpont E.
        Biomechanical effects of different varus and valgus alignments in medial unicompartmental knee arthroplasty.
        J Arthroplasty. 2016; 31: 2685-2691
        • Sawatari T.
        • Tsumura H.
        • Iesaka K.
        • Furushiro Y.
        • Torisu T.
        Three-dimensional finite element analysis of unicompartmental knee arthroplasty--the influence of tibial component inclination.
        J Orthop Res. 2005; 23: 549-554
        • Iesaka K.
        • Tsumura H.
        • Sonoda H.
        • Sawatari T.
        • Takasita M.
        • Torisu T.
        The effects of tibial component inclination on bone stress after unicompartmental knee arthroplasty.
        J Biomech. 2002; 35: 969-974
        • Inoue S.
        • Akagi M.
        • Asada S.
        • Mori S.
        • Zaima H.
        • Hashida M.
        The valgus inclination of the tibial component increases the risk of medial tibial condylar fractures in unicompartmental knee arthroplasty.
        J Arthroplasty. 2016; 31: 2025-2030
        • Woiczinski M.
        • Schröder C.
        • Paulus A.
        • Kistler M.
        • Jansson V.
        • Müller P.E.
        • et al.
        Varus or valgus positioning of the tibial component of a unicompartmental fixed-bearing knee arthroplasty does not increase wear.
        Knee Surg Sports Traumatol Arthrosc. 2020; 28: 3016-3021