title: Decompression without Fusion for Low-Grade Degenerative Spondylolisthesis.
abstract: METHODS
  Retrospective series.
  
  
  OBJECTIVE
  Assess results of decompression-only surgery for low-grade degenerative spondylolisthesis with consideration of instability.
  
  
  BACKGROUND
  There is no consensus on whether fusion or decompression-only surgery leads to better outcomes for patients with low-grade degenerative spondylolisthesis. Current trends support fusion but many studies are flawed due to over-generalization without consideration of radiological instability and their variable presentations and natural history.
  
  
  METHODS
  Patients with surgically treated degenerative spondylolisthesis from 1990-2013 were included. Clinical and radiological instability measures were included. Any residual or recurrence of symptoms, revision surgery performed and functional outcome scores including the numerical global rate of change scale, visual analogue scale, and modified Barthel index were measured. Follow-up periods for patients were divided into short-term (<5 years), mid-term (5-10 years) and long-term (>10 years).
  
  
  RESULTS
  A total of 64 patients were recruited. Mechanical low back pain was noted in 48 patients and most (85.4%) had relief of back pain postoperatively. Radiological instability was noted in 4 subjects by flexion-extension radiographs and 12 subjects with prone traction radiographs by increased disc height and reduction of olisthesis and slip angle. From the results of the short-term, mid-term and long-term follow-up, reoperation only occurred within the first 5-year follow-up period. All functional scores improved from preoperative to postoperative 1-year follow-up.
  
  
  CONCLUSIONS
  Decompression-only for low-grade degenerative spondylolisthesis has good long-term results despite instability. Further higher-level studies should be performed on this patient group with radiological instability to suggest the superior surgical option.
authors.affiliation: Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong, SAR, China.
authors.forename: Jason Pui Yin
authors.initials: JP
authors.lastname: Cheung
authors.affiliation: Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong, SAR, China.
authors.forename: Prudence Wing Hang
authors.initials: PW
authors.lastname: Cheung
authors.affiliation: Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong, SAR, China.
authors.forename: Kenneth Man Chee
authors.initials: KM
authors.lastname: Cheung
authors.affiliation: Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong, SAR, China.
authors.forename: Keith Dip Kei
authors.initials: KD
authors.lastname: Luk
keywords: Decompression; Degenerative; Fusion; Low-grade; Spondylolisthesis; Without