title: Comparison of multifidus muscle atrophy after posterior lumbar interbody fusion with conventional and cortical bone trajectory.
abstract: OBJECTIVE
  To determine if minimally invasive posterior interbody fusion with cortical bone trajectory (CBT) is associated with reduced paraspinal muscle damage compared to conventional open posterior lumbar interbody fusion (PLIF).
  
  
  METHODS
  Sixteen consecutive patients who underwent CBT were grouped into matched pairs with 16 patients who underwent conventional PLIF between May 2013 and January 2014, in terms of age, sex, body mass index, and spinal levels. Perioperative data and clinical data, including the Japanese Orthopedics Association (JOA) score, visual analogue scale (VAS) score, Oswestry Disability Index (ODI),before and after surgery were evaluated. Magnetic resonance imaging was performed preoperatively and 6 months postoperatively. The fat infiltration ratio was calculated.
  
  
  RESULTS
  Thirty-two patients with an 18-month follow-up period were evaluated. Clinical improvement, indicated by the VAS score for back and leg pain, ODI, and JOA score, was significant in both groups. However, there were no significant differences in operative time, blood loss, hospital stay duration, and recovery rate between the groups. The fat infiltration ratio was lower in the CBT group (p<0.05) than in the conventional PLIF group.
  
  
  CONCLUSIONS
  CBT is comparable with conventional PLIF with respect to short-term clinical outcomes but induced less multifidus muscle damage.
authors.affiliation: Department of Spinal Surgery, Jhong Jheng Orthopedic Hospital, Kaohsiung City, Taiwan, ROC.
authors.forename: Che-Wei
authors.initials: CW
authors.lastname: Hung
authors.affiliation: Department of Orthopedic Surgery, Jhong Jheng Orthopedic Hospital, Kaohsiung City, Taiwan, ROC.
authors.forename: Ming-Fang
authors.initials: MF
authors.lastname: Wu
authors.affiliation: Department of Orthopedic Surgery, Jhong Jheng Orthopedic Hospital, Kaohsiung City, Taiwan, ROC.
authors.forename: Rong-Tsan
authors.initials: RT
authors.lastname: Hong
authors.affiliation: Department of Radiology, Jhong Jheng Orthopedic Hospital, Kaohsiung City, Taiwan, ROC.
authors.forename: Mei-Jui
authors.initials: MJ
authors.lastname: Weng
authors.affiliation: Department of Spinal Surgery, Jhong Jheng Orthopedic Hospital, Kaohsiung City, Taiwan, ROC.
authors.forename: Gwo-Fane
authors.initials: GF
authors.lastname: Yu
authors.affiliation: Department of Spinal Surgery, Jhong Jheng Orthopedic Hospital, Kaohsiung City, Taiwan, ROC. Electronic address: georgekao10@hotmail.com.
authors.forename: Cheng-Hsing
authors.initials: CH
authors.lastname: Kao
mesh_terms: D000368:Aged; D001863:Bone Screws; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009133:Muscular Atrophy / Q000209:etiology*; D017063:Outcome Assessment, Health Care; D013123:Spinal Fusion / Q000009:adverse effects* / Q000379:methods*
keywords: Cortical trajectory pedicle screws; Minimally invasive spine surgery; Posterior lumbar interbody fusion; Spinal fusion; Spinal stenosis