STUDY DESIGN: Systematic review. OBJECTIVE: To provide a systematic review of published literature on the impact of subsidence on clinical outcomes and radiographic fusion rates after anterior cervical discectomy and fusion with plates or without plates. BACKGROUND: Subsidence of interbody implants is common after anterior cervical spine fusions. The impact of subsidence on fusion rates and clinical outcomes is unknown. METHODS: Systematic literature review on published articles on anterior cervical discectomy and fusion, which objectively measured graft subsidence, radiographic fusion rates, and clinical outcomes between April 1966 and December 2010. RESULTS: A total of 35 articles that measured subsidence and provided fusion rates and/or clinical outcomes were selected for inclusion. The mean subsidence rate ranged from 19.3% to 42.5%. The rate of subsidence based on the type of implant ranged from 22.8% to 35.9%. The incidence of subsidence was not impacted by the type of implant (P=0.98). The overall fusion rate of the combined studies was 92.8% and was not impacted by subsidence irrespective of subsidence definition or the measurement technique used (P=0.19). Clinical outcomes were evaluated in 27 of 35 studies with all studies reporting an improvement in patient outcomes postoperatively. CONCLUSIONS: Subsidence irrespective of the measurement technique or definition does not appear to have an impact on successful fusion and/or clinical outcomes. A validated definition and standard measurement technique for subsidence is needed to determine the actual incidence of subsidence and its impact on radiographic and clinical outcomes.
STUDY DESIGN: Systematic review. OBJECTIVE: To provide a systematic review of published literature on the impact of subsidence on clinical outcomes and radiographic fusion rates after anterior cervical discectomy and fusion with plates or without plates. BACKGROUND: Subsidence of interbody implants is common after anterior cervical spine fusions. The impact of subsidence on fusion rates and clinical outcomes is unknown. METHODS: Systematic literature review on published articles on anterior cervical discectomy and fusion, which objectively measured graft subsidence, radiographic fusion rates, and clinical outcomes between April 1966 and December 2010. RESULTS: A total of 35 articles that measured subsidence and provided fusion rates and/or clinical outcomes were selected for inclusion. The mean subsidence rate ranged from 19.3% to 42.5%. The rate of subsidence based on the type of implant ranged from 22.8% to 35.9%. The incidence of subsidence was not impacted by the type of implant (P=0.98). The overall fusion rate of the combined studies was 92.8% and was not impacted by subsidence irrespective of subsidence definition or the measurement technique used (P=0.19). Clinical outcomes were evaluated in 27 of 35 studies with all studies reporting an improvement in patient outcomes postoperatively. CONCLUSIONS: Subsidence irrespective of the measurement technique or definition does not appear to have an impact on successful fusion and/or clinical outcomes. A validated definition and standard measurement technique for subsidence is needed to determine the actual incidence of subsidence and its impact on radiographic and clinical outcomes.
Authors: Jun Dong; Meng Lu; Teng Lu; Baobao Liang; Junkui Xu; Jun Zhou; Hongjun Lv; Jie Qin; Xuan Cai; Sihua Huang; Haopeng Li; Dong Wang; Xijing He Journal: PLoS One Date: 2015-06-11 Impact factor: 3.240
Authors: Bartosz Godlewski; Adam Bebenek; Maciej Dominiak; Grzegorz Karpinski; Piotr Cieslik; Tomasz Pawelczyk Journal: Acta Neurochir (Wien) Date: 2022-04-26 Impact factor: 2.216
Authors: Abdul Fettah Buyuk; Ikemefuna Onyekwelu; Christian J Gaffney; Amir A Mehbod; John M Dawson; Timothy A Garvey; Benjamin Mueller; James D Schwender Journal: J Spine Surg Date: 2020-12