Anna Lang1, Sara Lener2, Lukas Grassner2, Anto Abramovic2, Claudius Thomé2, Dennis Päsler3, Jens Lehmberg4, Ralph Schär5, Sebastian Hartmann2. 1. Department of Neurosurgery, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria. anna.stocsits@i-med.ac.at. 2. Department of Neurosurgery, Medical University of Innsbruck, Anichstrasse 35, 6020, Innsbruck, Austria. 3. Department of Neurosurgery, University of Greifswald, Greifswald, Germany. 4. Department of Neurosurgery, Academic Hospital Bogenhausen Munich, Munich, Germany. 5. Department of Neurosurgery, University of Bern, Bern, Switzerland.
Abstract
INTRODUCTION: The instantaneous center of rotation (iCOR) of a motion segment has been shown to correlate with its total range of motion (ROM). Importantly, a correlation of the correct placement of cervical total disc replacement (cTDR) to preserve a physiological iCOR has been previously identified. However, changes of these parameters and the corresponding clinical relevance have hardly been analyzed. This study assesses the radiological and clinical correlation of iCOR and ROM following cTDR. MATERIALS/ METHODS: A retrospective multi-center observational study was conducted and radiological as well as clinical parameters were evaluated preoperatively and 1 year after cTDR with an unconstrained device. Radiographic parameters including flexion/extension X-rays (flex/ex), ROM, iCOR and the implant position in anterior-posterior direction (IP ap), as well as corresponding clinical parameters [(Neck Disability Index (NDI) and the visual analogue scale (VAS)] were assessed. RESULTS: 57 index segments of 53 patients treated with cTDR were analyzed. Pre- and post-operative ROM showed no significant changes (8.0° vs. 10.9°; p > 0.05). Significant correlations between iCOR and IP (Pearson's R: 0.6; p < 0.01) as well as between ROM and IP ap (Pearson's R: - 0.3; p = 0.04) were identified. NDI and VAS improved significantly (p < 0.01). A significant correlation between NDI and IP ap after 12 months (Pearson's R: - 0.39; p < 0.01) was found. CONCLUSION: Implantation of the tested prosthesis maintains the ROM and results in a physiological iCOR. The exact position of the device correlates with the clinical outcome and emphasize the importance of implant design and precise implant positioning.
INTRODUCTION: The instantaneous center of rotation (iCOR) of a motion segment has been shown to correlate with its total range of motion (ROM). Importantly, a correlation of the correct placement of cervical total disc replacement (cTDR) to preserve a physiological iCOR has been previously identified. However, changes of these parameters and the corresponding clinical relevance have hardly been analyzed. This study assesses the radiological and clinical correlation of iCOR and ROM following cTDR. MATERIALS/ METHODS: A retrospective multi-center observational study was conducted and radiological as well as clinical parameters were evaluated preoperatively and 1 year after cTDR with an unconstrained device. Radiographic parameters including flexion/extension X-rays (flex/ex), ROM, iCOR and the implant position in anterior-posterior direction (IP ap), as well as corresponding clinical parameters [(Neck Disability Index (NDI) and the visual analogue scale (VAS)] were assessed. RESULTS: 57 index segments of 53 patients treated with cTDR were analyzed. Pre- and post-operative ROM showed no significant changes (8.0° vs. 10.9°; p > 0.05). Significant correlations between iCOR and IP (Pearson's R: 0.6; p < 0.01) as well as between ROM and IP ap (Pearson's R: - 0.3; p = 0.04) were identified. NDI and VAS improved significantly (p < 0.01). A significant correlation between NDI and IP ap after 12 months (Pearson's R: - 0.39; p < 0.01) was found. CONCLUSION: Implantation of the tested prosthesis maintains the ROM and results in a physiological iCOR. The exact position of the device correlates with the clinical outcome and emphasize the importance of implant design and precise implant positioning.
Authors: Bruno C R Lazaro; Kemal Yucesoy; Kasim Z Yuksel; Izabela Kowalczyk; Doron Rabin; Marie Fink; Neil Duggal Journal: Neurosurg Focus Date: 2010-06 Impact factor: 4.047
Authors: Hans-Jörg Meisel; Lubomír Jurák; Jussi Antinheimo; Ricardo Arregui; Bernhard Bruchmann; Mario Čabraja; Fabrizio Caroli; Stefan Kroppenstedt; Jan Kryl; Juha Pohjola; Ian Shackleford; Steffen Sola; Peter Stosberg; Jan Stulik; Christian Woiciechowsky; Petr Suchomel Journal: J Neurosurg Spine Date: 2016-06-03
Authors: J Beaurain; P Bernard; T Dufour; J M Fuentes; I Hovorka; J Huppert; J P Steib; J M Vital; L Aubourg; T Vila Journal: Eur Spine J Date: 2009-05-12 Impact factor: 3.134