title: Comparison of clinical outcomes between laminoplasty, posterior decompression with instrumented fusion, and anterior decompression with fusion for K-line (-) cervical ossification of the posterior longitudinal ligament.
abstract: The K-line, which is a virtual line that connects the midpoints of the anteroposterior diameter of the spinal canal at C2 and C7 in a plain lateral radiogram, is a useful preoperative predictive indicator for sufficient decompression by laminoplasty (LMP) for ossification of the posterior longitudinal ligament (OPLL). K-line is defined as (+) when the peak of OPLL does not exceed the K-line, and is defined as (-) when the peak of OPLL exceeds the K-line. For patients with K-line (-) OPLL, LMP often results in poor outcome. The aim of the present study was to compare the clinical outcome of LMP, posterior decompression with instrumented fusion (PDF) and anterior decompression and fusion (ADF) for patients with K-line (-) OPLL.
  
  
  
  The present study included patients who underwent surgical treatment including LMP, PDF and ADF for K-line (-) cervical OPLL. We retrospectively compared the clinical outcome of those patients in terms of Japanese Orthopedic Association score (JOA score) recovery rate.
  
  
  
  JOA score recovery rate was significantly higher in the ADF group compared with that in the LMP group and the PDF group. The JOA score recovery rate in the PDF group was significantly higher than that in the LMP group.
  
  
  
  LMP should not be used for K-line (-) cervical OPLL. ADF is one of the suitable surgical treatments for K-line (-) OPLL. Both ADF and PDF are applicable for K-line (-) OPLL according to indications set by each institute and surgical decisions.
authors.affiliation: Department of Orthopedic Surgery, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-Ku, Chiba, 2608670, Japan. masaokod@gmail.com.
authors.forename: Masao
authors.initials: M
authors.lastname: Koda
authors.affiliation: Department of Orthopedic Surgery, Numazu City Hospital, Numazu, Japan.
authors.forename: Makondo
authors.initials: M
authors.lastname: Mochizuki
authors.affiliation: Department of Orthopedic Surgery, Nagasaki Rosai Hospital, Nagasaki, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Konishi
authors.affiliation: Department of Orthopedic Surgery, Numazu City Hospital, Numazu, Japan.
authors.forename: Atsuomi
authors.initials: A
authors.lastname: Aiba
authors.affiliation: Department of Orthopedic Surgery, Numazu City Hospital, Numazu, Japan.
authors.forename: Ryo
authors.initials: R
authors.lastname: Kadota
authors.affiliation: Department of Orthopedic Surgery, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-Ku, Chiba, 2608670, Japan.
authors.forename: Taigo
authors.initials: T
authors.lastname: Inada
authors.affiliation: Department of Orthopedic Surgery, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-Ku, Chiba, 2608670, Japan.
authors.forename: Koshiro
authors.initials: K
authors.lastname: Kamiya
authors.affiliation: Department of Orthopedic Surgery, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-Ku, Chiba, 2608670, Japan.
authors.forename: Mitsutoshi
authors.initials: M
authors.lastname: Ota
authors.affiliation: Department of Orthopedic Surgery, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-Ku, Chiba, 2608670, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Maki
authors.affiliation: Department of Orthopedic Surgery, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-Ku, Chiba, 2608670, Japan.
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Takahashi
authors.affiliation: Department of Orthopedic Surgery, University of Tsukuba, Tsukuba, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Yamazaki
authors.affiliation: Department of Orthopedic Surgery, Chiba Aoba Municipal Hospital, Chiba, Japan.
authors.forename: Chikato
authors.initials: C
authors.lastname: Mannoji
authors.affiliation: Department of Orthopedic Surgery, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-Ku, Chiba, 2608670, Japan.
authors.forename: Takeo
authors.initials: T
authors.lastname: Furuya
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D019299:Decompression, Surgical / Q000009:adverse effects / Q000379:methods*; D005260:Female; D006801:Humans; D065406:Laminoplasty / Q000009:adverse effects / Q000379:methods*; D017846:Longitudinal Ligaments / Q000000981:diagnostic imaging / Q000601:surgery; D008297:Male; D008875:Middle Aged; D017887:Ossification of Posterior Longitudinal Ligament / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery*; D011859:Radiography; D012189:Retrospective Studies; D013117:Spinal Cord Compression / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery; D013123:Spinal Fusion / Q000009:adverse effects / Q000379:methods*; D016896:Treatment Outcome
keywords: Anterior decompression; Anterior fusion; Cervical spine; Kyphosis; Laminoplasty; Myelopathy; OPLL; Posterior decompression; Posterior fusion; Surgical outcome