caa a22 4500 605456259 CHVBK 20210128100216.0 cr unu---uuuuu 210128e20150601xx s 000 0 eng 10.1007/s00167-015-3565-0 doi (NATIONALLICENCE)springer-10.1007/s00167-015-3565-0 Does patellofemoral geometry in TKA affect patellar position in mid-flexion? [Elektronische Daten] [Mo Saffarini, Stefano Zaffagnini, Simone Bignozzi, Francesca Colle, Maurilio Marcacci, David Dejour] Purpose: This study aimed to compare the position of the patella at 90° of flexion before and after implantation of two TKA models with identical tibiofemoral geometry but different trochlear and patellar designs. The hypothesis was that the design with the deeper ‘anatomic' trochlea could produce more natural patellar positions. Methods: Intra-operative navigation data were collected from 22 consecutive cases that received two TKA designs (9 HLS Noetos® and 13 HLS KneeTec®). Both implants were cemented postero-stabilised TKAs with mobile tibial inserts and patellar resurfacing. Operations were guided by a non-image-based system that recorded relative femoral, tibial and patellar positions pre- and post-operatively. Results: The two groups exhibited little difference in femoral internal-external rotation and anterior-posterior translation during knee flexion. The two groups exhibited significant differences in patellar position at 90° of flexion. Post-operatively, the patella was similarly shifted medially relative to the femur (Noetos 6.9mm, KneeTec 6.0mm, n.s.). Patellar flexion was equivalent in native knees (Noetos 18.3°, KneeTec 20.5°, n.s.), but in implanted knees, it was considerably different (Noetos 6.3°, KneeTec 23.5°, p=0.031). Conclusions: The present study compared intra-operative navigation data from two patient series that received TKA implants with identical tibiofemoral articular geometry but different patellofemoral designs. The results confirm that tibiofemoral kinematics are unchanged, but that patellar positions at 90° of flexion offer greater mechanical advantage to the quadriceps using the KneeTec than using the Noetos. The findings raise awareness of influence of patellofemoral geometry on mid-flexion kinematics and help surgeons select the most suitable implant for patients with weak quadriceps muscles or with history of patellar instability. Level of evidence: Comparative study, Level III. European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA), 2015 Total knee arthroplasty nationallicence Postero-stabilised knee nationallicence Component design nationallicence Femoral trochlea nationallicence Patellar kinematics nationallicence Patellar height nationallicence Patellar tendon angle nationallicence Saffarini Mo Accelerate Innovation Management SA, 1 Rue de la Navigation, 1201, Geneva, Switzerland aut Zaffagnini Stefano Clinica Ortopedica e Traumatologica II, Laboratorio di Biomeccanica ed Innovazione Tecnologica, Istituto Ortopedico Rizzoli, Via di Barbiano 1\10, 40136, Bologna, Italy aut Bignozzi Simone Clinica Ortopedica e Traumatologica II, Laboratorio di Biomeccanica ed Innovazione Tecnologica, Istituto Ortopedico Rizzoli, Via di Barbiano 1\10, 40136, Bologna, Italy aut Colle Francesca Clinica Ortopedica e Traumatologica II, Laboratorio di Biomeccanica ed Innovazione Tecnologica, Istituto Ortopedico Rizzoli, Via di Barbiano 1\10, 40136, Bologna, Italy aut Marcacci Maurilio Clinica Ortopedica e Traumatologica II, Laboratorio di Biomeccanica ed Innovazione Tecnologica, Istituto Ortopedico Rizzoli, Via di Barbiano 1\10, 40136, Bologna, Italy aut Dejour David Lyon-Ortho-Clinic, Clinique de la Sauvegarde, 8 Avenue Ben Gourion, 69009, Lyon, France aut Knee Surgery, Sports Traumatology, Arthroscopy Springer Berlin Heidelberg 23/6(2015-06-01), 1799-1807 0942-2056 23:6<1799 2015 23 167 https://doi.org/10.1007/s00167-015-3565-0 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00167-015-3565-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Saffarini Mo Accelerate Innovation Management SA, 1 Rue de la Navigation, 1201, Geneva, Switzerland aut NATIONALLICENCE 700 1- Zaffagnini Stefano Clinica Ortopedica e Traumatologica II, Laboratorio di Biomeccanica ed Innovazione Tecnologica, Istituto Ortopedico Rizzoli, Via di Barbiano 1\10, 40136, Bologna, Italy aut NATIONALLICENCE 700 1- Bignozzi Simone Clinica Ortopedica e Traumatologica II, Laboratorio di Biomeccanica ed Innovazione Tecnologica, Istituto Ortopedico Rizzoli, Via di Barbiano 1\10, 40136, Bologna, Italy aut NATIONALLICENCE 700 1- Colle Francesca Clinica Ortopedica e Traumatologica II, Laboratorio di Biomeccanica ed Innovazione Tecnologica, Istituto Ortopedico Rizzoli, Via di Barbiano 1\10, 40136, Bologna, Italy aut NATIONALLICENCE 700 1- Marcacci Maurilio Clinica Ortopedica e Traumatologica II, Laboratorio di Biomeccanica ed Innovazione Tecnologica, Istituto Ortopedico Rizzoli, Via di Barbiano 1\10, 40136, Bologna, Italy aut NATIONALLICENCE 700 1- Dejour David Lyon-Ortho-Clinic, Clinique de la Sauvegarde, 8 Avenue Ben Gourion, 69009, Lyon, France aut NATIONALLICENCE 773 0- Knee Surgery, Sports Traumatology, Arthroscopy Springer Berlin Heidelberg 23/6(2015-06-01), 1799-1807 0942-2056 23:6<1799 2015 23 167