title: Perioperative complications of primary posterior lumbar interbody fusion for nonisthmic spondylolisthesis: analysis of risk factors.
abstract: OBJECTIVE
  Although posterior lumbar interbody fusion (PLIF) is an excellent procedure to attain circumferential decompression, it is technically demanding and can lead to various surgical complications. The authors retrospectively reviewed consecutive patients with nonisthmic spondylolisthesis who underwent PLIF to reveal the incidence and risk factors for perioperative complications of PLIF.
  
  
  METHODS
  A total of 240 patients underwent PLIF. The fusion level was at L4-5 in 220, L3-4 in 18, and L5-S1 in 2. The medial walls of the fusion segment's facet joints were resected, and the VSP Spine System was used for the pedicle screw instrumentation. The operations were performed by 7 surgeons, who were divided into 4 groups according to their level of experience with spinal surgery.
  
  
  RESULTS
  The average operation time was 175 +/- 49 minutes, and the estimated blood loss was 746 +/- 489 ml. A total of 90 patients (37.5%) experienced complications; 41 (17%) experienced transient neurological complications, and 18 (7.5%) experienced permanent neurological complications. The mean neurological score according to the Japanese Orthopaedic Association improved from 14.3 +/- 3.8 to 24.7 +/- 4.0 in the patients without complications and from 14.8 +/- 3.6 to 24.0 +/- 3.9 in the patients with complications. Multivariate analysis concerning the relationship between complications and risk factors (operation time, estimated intraoperative blood loss, and surgeon experience) revealed that operation time was the only significant risk factor for complications.
  
  
  CONCLUSIONS
  Perioperative complications of PLIF were more frequent in this homogeneous study group than in other studies of various implants. Total excision of the facet joints might preclude neurological complications.
authors.affiliation: Department of Orthopaedic Surgery, Osaka Kosei-nenkin Hospital, Fukushima, Osaka, Japan. hosono-n@umin.net
authors.forename: Noboru
authors.initials: N
authors.lastname: Hosono
authors.forename: Masato
authors.initials: M
authors.lastname: Namekata
authors.forename: Takahiro
authors.initials: T
authors.lastname: Makino
authors.forename: Toshitada
authors.initials: T
authors.lastname: Miwa
authors.forename: Takashi
authors.initials: T
authors.lastname: Kaito
authors.forename: Noriyoshi
authors.initials: N
authors.lastname: Kaneko
authors.forename: Takeshi
authors.initials: T
authors.lastname: Fuji
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D008159:Lumbar Vertebrae; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000453:epidemiology*; D012189:Retrospective Studies; D012307:Risk Factors; D013123:Spinal Fusion / Q000009:adverse effects*; D013168:Spondylolisthesis / Q000209:etiology / Q000473:pathology / Q000601:surgery*