title: Clinical features of patients with pars defects identified in adulthood.
abstract: OBJECTIVE
  Lumbar spondylolysis is considered a stress fracture of the pars interarticularis that occurs during growth. However, it is sometimes insidious and identified in adults as pseudoarthrosis, the terminal-stage of spondylolysis. The purpose of this study was to identify the clinical features of patients with terminal-stage spondylolysis that first manifested during adulthood.
  
  
  METHODS
  Thirty-six patients (21 men, 15 women; mean age 55.8 years; age range 25-77 years) with low back pain (LBP) were studied. In all patients, lumbar spondylolysis had not been diagnosed until the first visit to our hospital. Patient data collected were history of athletic activity and LBP during their growth period and radiological findings, such as spinal level, displacement, and spina bifida occulta (SBO).
  
  
  RESULTS
  Among the 36 patients, including a patient with multi-level spondylolysis (L4 and L5), a total of 37 vertebrae with terminal-stage spondylolysis were identified. Twenty-three (89.2 %) of the 37 vertebrae had L5 spondylolysis. Sixteen patients (44.4 %) had no history of athletic activity, 26 (72.2 %) had no experience of LBP during their growth period, and 14 (38.9 %) had neither. Twenty of the 37 vertebrae (70.4 %) involved displacement (grade 1 = 14; grade 2 = 6). In nine patients (25.0 %; eight men, one woman), SBO of the sacrum was accompanied by L5 spondylolysis.
  
  
  CONCLUSIONS
  Approximately 90 % of patients with terminal-stage spondylolysis that was first diagnosed in adulthood involved the L5. Also, about 40 % had no history of athletic activity or experience of LBP during their growth period. In addition, only some patients with L5 spondylolysis had SBO, and all but one of these patients was male. This suggests that male patients with L5 spondylolysis may have some congenital predisposition.
authors.affiliation: Department of Orthopaedic Surgery, Institute of Health Biosciences, Tokushima University, 3-18-15 Kuramoto-cho, Tokushima, 770-8503, Japan. norinoridowluck@yahoo.co.jp.
authors.forename: Toshinori
authors.initials: T
authors.lastname: Sakai
authors.affiliation: Department of Orthopaedic Surgery, Institute of Health Biosciences, Tokushima University, 3-18-15 Kuramoto-cho, Tokushima, 770-8503, Japan.
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Goda
authors.affiliation: Department of Orthopaedic Surgery, Institute of Health Biosciences, Tokushima University, 3-18-15 Kuramoto-cho, Tokushima, 770-8503, Japan.
authors.forename: Fumitake
authors.initials: F
authors.lastname: Tezuka
authors.affiliation: Department of Orthopaedic Surgery, Institute of Health Biosciences, Tokushima University, 3-18-15 Kuramoto-cho, Tokushima, 770-8503, Japan.
authors.forename: Mitsunobu
authors.initials: M
authors.lastname: Abe
authors.affiliation: Department of Orthopaedic Surgery, Institute of Health Biosciences, Tokushima University, 3-18-15 Kuramoto-cho, Tokushima, 770-8503, Japan.
authors.forename: Kazuta
authors.initials: K
authors.lastname: Yamashita
authors.affiliation: Department of Orthopaedic Surgery, Institute of Health Biosciences, Tokushima University, 3-18-15 Kuramoto-cho, Tokushima, 770-8503, Japan.
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Takata
authors.affiliation: Department of Orthopaedic Surgery, Institute of Health Biosciences, Tokushima University, 3-18-15 Kuramoto-cho, Tokushima, 770-8503, Japan.
authors.forename: Kosaku
authors.initials: K
authors.lastname: Higashino
authors.affiliation: Department of Orthopaedic Surgery, Institute of Health Biosciences, Tokushima University, 3-18-15 Kuramoto-cho, Tokushima, 770-8503, Japan.
authors.forename: Akihiro
authors.initials: A
authors.lastname: Nagamachi
authors.affiliation: Department of Orthopaedic Surgery, Institute of Health Biosciences, Tokushima University, 3-18-15 Kuramoto-cho, Tokushima, 770-8503, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Sairyo
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012737:Sex Factors; D013169:Spondylolysis / Q000175:diagnosis / Q000473:pathology*; D013177:Sports / Q000706:statistics & numerical data
keywords: Adult; Lumbar spondylolysis; Pars interarticularis; Pathophysiology; Spina bifida occulta