Five-year follow-up of clinical and radiological outcomes of LP-ESP elastomeric lumbar total disc replacement in active patients

BACKGROUND CONTEXT: The surgical treatment of degenerative disc disease at the lumbar spine may involve fusion. Total disc replacement (TDR) is an alternative treatment to avoid fusion related adverse events, specifically adjacent segment disease. New generation of elastomeric non articulating devices has been developed to more effectively replicate the shock absorption and flexural stiffness of native disc. PURPOSE: To report 5 years clinical and radiographic outcomes, range of motion (ROM), and position of the center of rotation after a viscoelastic lumbar TDR. STUDY DESIGN: Prospective observational cohort study PATIENT SAMPLE: Sixty-one patients OUTCOME MEASURES: The clinical evaluation was based on visual analog scale (VAS) for pain, Oswestry disability index (ODI) score, short form-36 (SF-36) including the physical component summary (PCS) and the mental component summary (MCS), and general health questionnaire-28 (GHQ28). The radiological outcomes were ROM and position of the center of rotation at the index and the adjacent levels and the adjacent disc height changes. METHODS: Our study group included 61 consecutive patients with monosegmental disc replacement. We selected patients who could provide a global lumbar spine mobility analysis (intermediate functional activity according to the Baecke score). Hybrid constructs had been excluded. Only the cases with complete clinical and radiological follow-up at 3. 6, 12. 24, and 60 months were included. RESULTS: There was a significant improvement in VAS (3.3 +/- 25 vs. 6.6 +/- 1 .7, p<.001), in ODI (20 +/- 17.9 vs. 51.2 +/- 14.6, p<.001), GHQ28 (52.6 +/- 15.5 vs. 64.2 +/- 15.6, p<.001), SF-36 PCS (58.8 +/- 4.8 vs. 32.4 +/- 3.4, p<.001). and SF-36 MCS (60.7 +/- 6 vs. 42.3 +/- 3.4, p<.001). The mean location centers of the index level and adjacent discs were comparable to those previously published in asymptomatic patients. According to the definition of Zigler and Delamarter, all of our cases remained grade 0 for adjacent level disc height (within 25% of normal). CONCLUSIONS: This series reports significant improvement in midterm follow-up after TDR, which is consistent with previously published studies but with a lower rate of revision surgery and no adjacent level disease pathologies. The radiographic assessment of the patients demonstrated the quality of functional reconstruction of the lumbar spine after LP-ESP viscoelastic disc replacement. (C) 2018 Published by Elsevier Inc.