C Mayer1, B Bittersohl2, M Haversath3, A Franz4, R Krauspe2, M Jäger1, C Zilkens4. 1. Department of Orthopaedics and Trauma Surgery, University of Duisburg-Essen, St. Marien Hospital Mülheim, Mülheim, Germany. 2. Department of Orthopaedics and Trauma Surgery, University of Duesseldorf, University Hospital Duesseldorf, Duesseldorf, Germany. 3. Department of Orthopaedics, St. Vinzenz Hospital, Duesseldorf, Germany. 4. Department of Orthopaedics, Orthoparc Clinic, Cologne, Germany.
Abstract
INTRODUCTION: Introducing a new arthroplasty system into clinical routine is challenging and could have an effect on early results. Since UKA are known to have failure mechanisms related to technical factors, reliable results and easy adoption are ideal. The question remains whether there are differences in objective procedure parameters in the early learning curve of different UKA systems. METHODS: two different UKA implants (Biomet Oxford[BO] followed by Conformis iuni[CI]) were introduced consecutively into clinical routine. We retrospectively analyzed the first 20 cases of each implant for one arthroplasty surgeon regarding operating time, correction of the mechanical axis, learning curve parameters, and revision rate of implants for 1.5 years postoperatively. RESULTS: Operating time (BO:98.3 ± 26.3min, CI:83.85 ± 21.8min (p < 0.078)), and tourniquet time differed in favor of the CI implant (BO:97.5 ± 29.5min; CI:73.5 ± 33.2 min; p < 0.017)). Mechanical alignment was restored in boths (preop:BO:mean 2.9°varus, CI:2.7°varus, postop:BOmean1.3°varus, CI:1°varus), while one BO patient and two CI patients were overcorrected. Operating time decreased from the first five implants to implants 16-20 for CI (95.2 ± 18.5min to 69 ± 21.5min, p < 0.076) and BO (130.6 ± 27.6min to 78 ± 17.3min, p < 0.009). Within 18 months of follow-up, 2 BO and 1 CI implants were revised. CONCLUSION: The introduction of an UKA implant was associated with longer surgery in both implants. Procedure time seems to differ between implants, while a learning curve was observed regarding instrumentation. CI implants seem to be reliable and adaptable in a medium-volume practice. The early results of this retrospective single-surgeon study were in favor of the individualized implant. Certainly, further studies encompassing larger cohorts with various implants are needed.
INTRODUCTION: Introducing a new arthroplasty system into clinical routine is challenging and could have an effect on early results. Since UKA are known to have failure mechanisms related to technical factors, reliable results and easy adoption are ideal. The question remains whether there are differences in objective procedure parameters in the early learning curve of different UKA systems. METHODS: two different UKA implants (Biomet Oxford[BO] followed by Conformis iuni[CI]) were introduced consecutively into clinical routine. We retrospectively analyzed the first 20 cases of each implant for one arthroplasty surgeon regarding operating time, correction of the mechanical axis, learning curve parameters, and revision rate of implants for 1.5 years postoperatively. RESULTS: Operating time (BO:98.3 ± 26.3min, CI:83.85 ± 21.8min (p < 0.078)), and tourniquet time differed in favor of the CI implant (BO:97.5 ± 29.5min; CI:73.5 ± 33.2 min; p < 0.017)). Mechanical alignment was restored in boths (preop:BO:mean 2.9°varus, CI:2.7°varus, postop:BOmean1.3°varus, CI:1°varus), while one BO patient and two CI patients were overcorrected. Operating time decreased from the first five implants to implants 16-20 for CI (95.2 ± 18.5min to 69 ± 21.5min, p < 0.076) and BO (130.6 ± 27.6min to 78 ± 17.3min, p < 0.009). Within 18 months of follow-up, 2 BO and 1 CI implants were revised. CONCLUSION: The introduction of an UKA implant was associated with longer surgery in both implants. Procedure time seems to differ between implants, while a learning curve was observed regarding instrumentation. CI implants seem to be reliable and adaptable in a medium-volume practice. The early results of this retrospective single-surgeon study were in favor of the individualized implant. Certainly, further studies encompassing larger cohorts with various implants are needed.
Authors: William C Schroer; C Lowry Barnes; Paul Diesfeld; Angela LeMarr; Rachel Ingrassia; Diane J Morton; Mary Reedy Journal: Clin Orthop Relat Res Date: 2013-08-02 Impact factor: 4.176
Authors: Constantin Mayer; Alexander Franz; Jan-Frieder Harmsen; Fina Queitsch; Michael Behringer; Johannes Beckmann; Rüdiger Krauspe; Christoph Zilkens Journal: J Orthop Date: 2017-06-24
Authors: Mona Badawy; Anne M Fenstad; Christoffer A Bartz-Johannessen; Kari Indrekvam; Leif I Havelin; Otto Robertsson; Annette W-Dahl; Antti Eskelinen; Keijo Mäkelä; Alma B Pedersen; Henrik M Schrøder; Ove Furnes Journal: BMC Musculoskelet Disord Date: 2017-09-07 Impact factor: 2.362