title: Dynamic stabilization for L4-5 spondylolisthesis: comparison with minimally invasive transforaminal lumbar interbody fusion with more than 2 years of follow-up.
abstract: OBJECTIVE In the past decade, dynamic stabilization has been an emerging option of surgical treatment for lumbar spondylosis. However, the application of this dynamic construct for mild spondylolisthesis and its clinical outcomes remain uncertain. This study aimed to compare the outcomes of Dynesys dynamic stabilization (DDS) with minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) for the management of single-level spondylolisthesis at L4-5. METHODS This study retrospectively reviewed 91 consecutive patients with Meyerding Grade I spondylolisthesis at L4-5 who were managed with surgery. Patients were divided into 2 groups: DDS and MI-TLIF. The DDS group was composed of patients who underwent standard laminectomy and the DDS system. The MI-TLIF group was composed of patients who underwent MI-TLIF. Clinical outcomes were evaluated by visual analog scale for back and leg pain, Oswestry Disability Index, and Japanese Orthopaedic Association scores at each time point of evaluation. Evaluations included radiographs and CT scans for every patient for 2 years after surgery. RESULTS A total of 86 patients with L4-5 spondylolisthesis completed the follow-up of more than 2 years and were included in the analysis (follow-up rate of 94.5%). There were 64 patients in the DDS group and 22 patients in the MI-TLIF group, and the overall mean follow-up was 32.7 months. Between the 2 groups, there were no differences in demographic data (e.g., age, sex, and body mass index) or preoperative clinical evaluations (e.g., visual analog scale back and leg pain, Oswestry Disability Index, and Japanese Orthopaedic Association scores). The mean estimated blood loss of the MI-TLIF group was lower, whereas the operation time was longer compared with the DDS group (both p < 0.001). For both groups, clinical outcomes were significantly improved at 6, 12, 18, and 24 months after surgery compared with preoperative clinical status. Moreover, there were no differences between the 2 groups in clinical outcomes at each evaluation time point. Radiological evaluations were also similar and the complication rates were equally low in both groups. CONCLUSIONS At 32.7 months postoperation, the clinical and radiological outcomes of DDS were similar to those of MI-TLIF for Grade I degenerative spondylolisthesis at L4-5. DDS might be an alternative to standard arthrodesis in mild lumbar spondylolisthesis. However, unlike fusion, dynamic implants have issues of wearing and loosening in the long term. Thus, the comparable results between the 2 groups in this study require longer follow-up to corroborate.
authors.affiliation: Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital;|School of Medicine and.
authors.forename: Chao-Hung
authors.initials: CH
authors.lastname: Kuo
authors.affiliation: Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital;|School of Medicine and.
authors.forename: Peng-Yuan
authors.initials: PY
authors.lastname: Chang
authors.affiliation: Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital;|School of Medicine and.
authors.forename: Jau-Ching
authors.initials: JC
authors.lastname: Wu
authors.affiliation: Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital;|School of Medicine and.
authors.forename: Hsuan-Kan
authors.initials: HK
authors.lastname: Chang
authors.affiliation: Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital;|School of Medicine and.|Institute of Pharmacology, National Yang-Ming University; and.
authors.forename: Li-Yu
authors.initials: LY
authors.lastname: Fay
authors.affiliation: Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital;|School of Medicine and.|Molecular Medicine Program, Taiwan International Graduate Program, Academia Sinica, Taipei, Taiwan.
authors.forename: Tsung-Hsi
authors.initials: TH
authors.lastname: Tu
authors.affiliation: Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital;|School of Medicine and.|Institute of Pharmacology, National Yang-Ming University; and.
authors.forename: Henrich
authors.initials: H
authors.lastname: Cheng
authors.affiliation: Department of Neurosurgery, Neurological Institute, Taipei Veterans General Hospital;|School of Medicine and.
authors.forename: Wen-Cheng
authors.initials: WC
authors.lastname: Huang
mesh_terms: D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000379:methods / Q000639:trends*; D011859:Radiography; D012189:Retrospective Studies; D013123:Spinal Fusion / Q000379:methods / Q000639:trends*; D013168:Spondylolisthesis / Q000000981:diagnostic imaging* / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome
keywords: ASD = adjacent-segment disease; DDS = Dynesys dynamic stabilization; Dynesys; EBL = estimated blood loss; JOA = Japanese Orthopaedic Association; MI = minimally invasive; ODI = Oswestry Disability Index; PET = polyethylene-terephthalate; TLIF; TLIF = transforaminal lumbar interbody fusion; VAS = visual analog scale; functional outcome; minimally invasive; spondylolisthesis