The Oxford Unicompartmental Knee Fails at a High Rate in a High-volume Knee Practice
Rent the article at a discountRent now
* Final gross prices may vary according to local VAT.Get Access
The Oxford knee is a unicompartmental implant featuring a mobile-bearing polyethylene component with excellent long-term survivorship results reported by the implant developers and early adopters. By contrast, other studies have reported higher revision rates in large academic practices and in national registries. Registry data have shown increased failure with this implant especially by lower-volume surgeons and institutions.
In the setting of a high-volume knee arthroplasty practice, we sought to determine (1) the failure rate of the Oxford unicompartmental knee implant using a failure definition for aseptic loosening that combined clinical features, plain radiographs, and scintigraphy, and (2) whether increased experience with this implant would decrease failure rate, if there is a learning curve effect.
Eighty-three Oxford knee prostheses were implanted between September 2005 and July 2008 by the principal investigator. Radiographic and clinical data were available for review for all cases. A failed knee was defined as having recurrent pain after an earlier period of recovery from surgery, progressive radiolucent lines compared with initial postoperative radiographs, and a bone scan showing an isolated area of uptake limited to the area of the replaced compartment.
Eleven knees in this series failed (13%); Kaplan-Meier survivorship was 86.5% (95% CI, 78.0%–95.0%) at 5 years. Failure occurrences were distributed evenly over the course of the study period. No learning curve effect was identified.
Based on these findings, including a high failure rate of the Oxford knee implant and the absence of any discernible learning curve effect, the principal investigator no longer uses this implant.
Level of Evidence
Level III, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.
- Baker, P, Jameson, S, Critchley, R, Gregg, P, Deehan, D (2013) Center and surgeon volume influence the revision rate following unicondylar knee replacement: an analysis of 23,400 medial cemented unicondylar knee replacements. J Bone Joint Surg Am. 95: pp. 702-709 CrossRef
- Berbari, E, Mabry, T, Tsaras, G, Spangehl, M, Erwin, PJ, Murad, MH, Steckelberg, J, Osmon, D (2010) Inflammatory blood laboratory levels as markers of prosthetic joint infection: a systematic review and meta-analysis. J Bone Joint Surg Am. 92: pp. 2102-2109 CrossRef
- Berend, KR, Lombardi, AV (2007) Liberal indications for minimally invasive Oxford unicondylar arthroplasty provide rapid functional recovery and pain relief. Surg Technol Int. 16: pp. 193-197
- Chou, DT, Swamy, GN, Lewis, JR, Badhe, NP (2012) Revision of failed unicompartmental knee replacement to total knee replacement. Knee. 19: pp. 356-359 CrossRef
- Choy, WS, Kim, KJ, Lee, SK, Yang, DS, Lee, NK (2011) Mid-term results of Oxford medial unicompartmental knee arthroplasty. Clin Orthop Surg. 3: pp. 178-183 CrossRef
- Dervin, GF, Carruthers, C, Freibel, RJ, Gianchino, AA, Kim, PR, Thurston, PR (2011) Initial experience with the Oxford unicompartmental knee arthroplasty. J Arthroplasty. 26: pp. 192-197 CrossRef
- Ericsson, KA, Krampe, RT, Tesch-Romer, C (1993) The role of deliberate practice in the acquisition of expert performance. Psychol Rev. 100: pp. 363-406 CrossRef
- Goodfellow, JW, O’Connor, JJ, Murray, DW (2010) A critique of revision rate as an outcome measure: re-interpretation of knee joint registry data. J Bone Joint Surg Br. 92: pp. 1628-1631
- Gulati, A, Chau, R, Pandit, HG, Gray, H, Price, AJ, Dodd, CA, Murray, DW (2009) The incidence of physiological radiolucency following Oxford unicompartmental knee replacement and its relationship to outcome. J Bone Joint Surg Br. 91: pp. 896-902
- Hamilton, WG, Ammeen, D, Engh, CA, Engh, GA (2010) Learning curve with minimally invasive unicompartmental knee arthroplasty. J Arthroplasty. 25: pp. 735-740 CrossRef
- Heller, S, Fenichel, I, Salai, M, Luria, T, Velkes, S (2009) The Oxford unicompartmental knee prosthesis for the treatment of medial compartment knee disease: 2 to 5 year follow-up. Isr Med Assoc J. 11: pp. 266-268
- Kalra, S, Smith, TO, Berko, B, Walton, NP (2011) Assessment of radiolucent lines around the Oxford unicompartmental knee replacement: sensitivity and specificity for loosening. J Bone Joint Surg Br. 93: pp. 777-781
- Kaplan, EL, Meier, P (1958) Nonparametric estimation from incomplete observations. J Am Stat Assoc. 53: pp. 457-481 CrossRef
- Kendrick, BJ, Simpson, DJ, Kapstein, BL, Valstar, ER, Gill, HS, Murray, DW, Price, AJ (2011) Polyethylene wear of mobile-bearing unicompartmental knee replacement at 20 years. J Bone Joint Surg Br. 93: pp. 470-475
- Kuipers, BM, Kollen, BJ, Bots, PC, Burger, BJ, Raay, JJ, Tulp, NJ, Verheyen, CC (2010) Factors associated with reduced early survival in the Oxford phase III medial unicompartmental knee replacement. Knee. 17: pp. 48-52 CrossRef
- Lewold, S, Goodman, S, Knutson, K, Robertson, O, Lidgren, L (1995) Oxford meniscal bearing knee versus the Marmor knee in unicompartmental arthroplasty for arthrosis: a Swedish multicenter survival study. J Arthroplasty. 10: pp. 722-731 CrossRef
- Mercier, N, Wimsey, S, Saragaglia, D (2010) Long-term clinical results of the Oxford medial unicompartmental knee arthroplasty. Int Orthop. 34: pp. 1137-1143 CrossRef
- Murray, DW, Goodfellow, JW, O’Connor, JJ (1998) The Oxford medial unicompartmental arthroplasty: a ten-year survival study. J Bone Joint Surg Br. 80: pp. 983-989 CrossRef
- New Zealand Orthopaedic Association. The New Zealand Joint Registry. Thirteen year report: January 1999–December 2012. Available at: www.nzoa.org.nz/nz-joint-registry. Accessed July 3, 2013.
- Pandit H, Jenkins C, Barker K, Dodd CA, Murray DW. The Oxford medial unicompartmental knee replacement using a minimally-invasive approach. J Bone Joint Surg Br. 2006;88:54–60.
- Pearse, AJ, Hooper, GJ, Rothwell, A, Frampton, C (2010) Survival and functional outcome after revision of a unicompartmental to a total knee replacement: the New Zealand National Joint Registry. J Bone Joint Surg Br. 92: pp. 508-512 CrossRef
- Price, AJ, Svard, U (2011) A second decade lifetable survival analysis of the Oxford unicompartmental knee arthroplasty. Clin Orthop Relat Res. 469: pp. 174-179 CrossRef
- Rea, P, Short, A, Pandit, H, Price, AJ, Kyberd, P, Beard, DJ, Gill, HS, Murray, DW (2007) Radiolucency and migration after Oxford unicompartmental knee arthroplasty. Orthopedics. 30: pp. 24-27
- Robertsson, O, Knutson, K, Lewold, S, Lidgren, L (2001) The routine of surgical management reduces failure after unicompartmental knee arthroplasty. J Bone Joint Surg Br. 83: pp. 45-49 CrossRef
- Schroer, WC, Calvert, GT, Diesfeld, PJ, Reedy, ME, LeMarr, AR (2008) Effects of increased surgical volume on total knee arthroplasty complications. J Arthroplasty. 23: pp. 61-67 CrossRef
- Schroer WC, Stormont DM, Pietrzak WS. Seven-year survivorship and functional outcomes of the high-flexion Vanguard complete knee system. J Arthroplasty. 2013 May 20. pii: S0883-5403(13)00311-2 [Epub ahead of print].
- Vorlat, P, Putzeys, G, Cottenie, D, Isacker, T, Pouliart, N, Handelberg, F, Casteleyn, PP, Gheysen, F, Verdonk, R (2006) The Oxford unicompartmental knee prosthesis: an independent 10-year survival analysis. Knee Surg Sports Traumatol Arthrosc. 14: pp. 40-45 CrossRef
- Zermatten, P, Munzinger, U (2012) The Oxford II medial unicompartmental knee arthroplasty: an independent 10-year survival study. Acta Orthop Belg. 78: pp. 203-209
- The Oxford Unicompartmental Knee Fails at a High Rate in a High-volume Knee Practice
Clinical Orthopaedics and Related Research®
Volume 471, Issue 11 , pp 3533-3539
- Cover Date
- Print ISSN
- Online ISSN
- Springer US
- Additional Links
- Industry Sectors
- Author Affiliations
- 1. St Louis Joint Replacement Institute, SSM DePaul Health Center, 12266 DePaul Drive, Suite 220, St Louis, MO, 63044, USA
- 2. Arkansas Specialty Orthopaedics, Little Rock, AR, USA