title: Current Evidence Regarding the Etiology, Prevalence, Natural History, and Prognosis of Pediatric Lumbar Spondylolysis: A Report from the Scoliosis Research Society Evidence-Based Medicine Committee.
abstract: METHODS
  Structured literature review.
  
  
  OBJECTIVE
  To assess the current state of evidence as a first step in the development of practice guidelines for pediatric spondylolysis.
  
  
  BACKGROUND
  Progress in published medical knowledge, changes in societal expectations, and developments in health care economics have led medical organizations to develop evidence-based documents and products.
  
  
  METHODS
  A comprehensive literature search for pediatric spondylolysis was performed with the assistance of a medical librarian. The authors reviewed citations and abstracts. Abstracts were reviewed for exclusions and data from included studies were analyzed by committee. A total of 44 articles provided the best available evidence for the questions of etiology, prevalence, natural history, and prognosis: 9 were graded as level I evidence, 23 were level II, 3 were level III, and 9 were level IV. No level V studies were included in the final list.
  
  
  RESULTS
  There is good evidence that pediatric lumbar spondylolysis is an acquired fracture of the pars interarticularis that can occur unilaterally or bilaterally. Evidence shows that when chronic, bilateral pars defects develop, 43% to 74% of patients will progress to grade 1 or 2 spondylolisthesis. In addition, unilateral, incomplete, and early lesions can obtain bony union. With or without bony union or spondylolisthesis, short-term symptom resolution is the norm. Long-term prognosis is less clear, but there is fair evidence that most patients will have lumbar symptoms compared with the general population. There is also fair evidence that some patients will develop significant symptoms as adults and will undergo surgical treatment. There is insufficient knowledge to predict which patients will continue to do well in the long term with conservative or no treatment and which patients will develop symptoms significant enough to warrant early intervention.
  
  
  CONCLUSIONS
  The current medical literature provides fair to good evidence for clinically relevant questions regarding the etiology, prevalence, natural history, and prognosis of pediatric spondylolysis.
authors.affiliation: Department of Orthopaedic Surgery, University of Louisville School of Medicine, 550 S. Jackson Street, 1st Floor ACB, Louisville, KY 40202, USA; Norton Leatherman Spine Center, 210 East Gray Street, Suite 900, Louisville, KY 40202, USA. Electronic address: chcraw01@gmail.com.
authors.forename: Charles H
authors.initials: CH
authors.lastname: Crawford
authors.affiliation: Department of Orthopaedic Surgery, University of Minnesota, 2450 Riverside Avenue South, Suite R200, Minneapolis, MN 55454, USA.
authors.forename: Charles G T
authors.initials: CG
authors.lastname: Ledonio
authors.affiliation: Department of Orthopedic Surgery, Rocky Mountain Hospital for Children, 2055 High Street, Suite 130, Denver, CO 80205, USA.
authors.forename: Robert Shay
authors.initials: RS
authors.lastname: Bess
authors.affiliation: Department of Orthopedic Surgery, Washington University School of Medicine, 660 South Euclid Avenue, Campus Box 8233, St. Louis, MO 63110, USA.
authors.forename: Jacob M
authors.initials: JM
authors.lastname: Buchowski
authors.affiliation: Department of Orthopedic Surgery, University of Kansas Medical Center, 3901 Rainbow Boulevard, Mail Stop 3017, Kansas City, KS, 66160, USA.
authors.forename: Douglas C
authors.initials: DC
authors.lastname: Burton
authors.affiliation: Department of Orthopaedic Surgery, Stanford School of Medicine, 450 Broadway Street, Pavilion C, 4th Floor, Redwood City, CA 94063-6342, USA.
authors.forename: Serena S
authors.initials: SS
authors.lastname: Hu
authors.affiliation: Department of Orthopaedic Surgery, New York University Langone Medical Center, 820 2nd Avenue, Suite 7A, New York, NY 10017, USA.
authors.forename: Baron S H
authors.initials: BS
authors.lastname: Lonner
authors.affiliation: Department of Orthopaedic Surgery, University of Minnesota, 2450 Riverside Avenue South, Suite R200, Minneapolis, MN 55454, USA.
authors.forename: David W
authors.initials: DW
authors.lastname: Polly
authors.affiliation: Department of Neurosurgery, University of Virginia, PO Box 800212, Charlottesville, VA 22908, USA.
authors.forename: Justin S
authors.initials: JS
authors.lastname: Smith
authors.affiliation: Department of Orthopaedics, University of Rochester School of Medicine and Dentistry, 601 Elmwood Avenue, Box 665, Rochester, NY 14642, USA.
authors.forename: James O
authors.initials: JO
authors.lastname: Sanders
keywords: Isthmic spondylolysis; Pars interarticularis; Spondylolysis; Structured literature review