Skeletal Radiology

, Volume 41, Issue 7, pp 817–822 | Cite as

Lumbar lordosis and pars interarticularis fractures: a case–control study

  • William G. BuggEmail author
  • Mark Lewis
  • Arne Juette
  • John G. Cahir
  • Andoni P. Toms
Scientific Article



The aim of this study is to examine the relationship between lumbar lordosis and pars interarticularis fractures.

Materials and methods

In this retrospective case–control study we compare the angle of lumbar lordosis and the angle of the S1 vertebral endplate (as a measure of pelvic tilt) in patients with bilateral L5 pars interarticularis fractures with age- and sex-matched control cases with normal MRI examinations of the lumbar spine. Twenty-nine cases of bilateral L5 pars interarticularis fractures with matched control–cases were identified on MRI (16 male, 13 female, age 9–63 years). The angle of lordosis was measured between the inferior L4 and superior S1 vertebral endplates on a standing lateral lumbar spine radiograph for both groups.


The mean angle of lordosis about the L5 vertebra was 36.9° (SD = 6.5°) in the pars interarticularis fracture group, and 30.1° (SD = 6.4°) in the control group. The difference between the two groups was significant (mean difference 6.8°, Student’s t test: P < 0.001). The mean angle of sacral tilt measured was 122.2° (SD = 10.16°) for controls and 136.4° (SD = 10.86°) for patients with pars defects. The difference in the means of 14.2° was statistically significantly different (P < 0.0001).


Sacral tilt represented by a steeply angled superior endplate of S1 is associated with a significantly increased angle of lordosis, between L4 and S1, and pars fractures at L5. Steep angulation of the first sacral vertebral segment maybe the predisposing biomechanical factor that leads to pincer-like impingement of the pars interarticularis and then spondylolysis.


Lordosis Lumbar vertebrae Spondylolysis MRI 


Funding and grants



  1. 1.
    Wiltse LL, Widell EH, Jackson DW. Fatigue fracture: the basic lesion in isthmic spondylolisthesis. J Bone Joint Surg Am. 1975;57:17–22.PubMedGoogle Scholar
  2. 2.
    Cyron BM, Hutton WC, Troup JDG. Spondylolytic fractures. J Bone Joint Surg. 1976;58:462–6.Google Scholar
  3. 3.
    Ward CV, Latimer B. Human evolution and the development of spondylolysis. Spine. 2005;16:1808–14.CrossRefGoogle Scholar
  4. 4.
    Jackson DW, Wiltse LL, Dingeman RD, et al. Stress reactions involving the pars interarticularis in young athletes. Am J Sport Med. 1981;9:304–12.CrossRefGoogle Scholar
  5. 5.
    Fredrickson BE, Baker D, McHolick WJ, et al. The natural history of spondylolysis and spondylolisthesis. J Bone Joint Surg. 1984;66:699–707.PubMedGoogle Scholar
  6. 6.
    Dietrich M, Kurowski P. The importance of mechanical factors in the etiology of spondylolysis: a model analysis of loads and stresses in human lumbar spine. Spine. 1985;10:532–42.PubMedCrossRefGoogle Scholar
  7. 7.
    Gerbino PG, Micheli LJ. Back injuries in the young athlete. Clin Sport Med. 1995;14:571–90.Google Scholar
  8. 8.
    Jackson DW, Wiltse LL, Cirincione RJ. Spondylolysis in the female gymnast. Clin Orthop. 1976;117:658–73.Google Scholar
  9. 9.
    Grobler L, Robertson P, Novotny J, Pope M. Etiology of spondylolisthesis. Assessment of the role played by lumbar facet joint morphology. Spine. 1993;18:80–91.PubMedCrossRefGoogle Scholar
  10. 10.
    Masharawi YM, Dar G, Peleg S, et al. Lumbar facet anatomy changes in spondylolysis: a comparative skeletal study. Eur Spine J. 2007;16:993–9.PubMedCrossRefGoogle Scholar
  11. 11.
    Mac-Thiong J-M, Pinel-Giroux F-M, de Guise JA, Labelle H. Comparison between constrained and non-constrained Cobb techniques for the assessment of thoracic kyphosis and lumbar lordosis. Eur Spine J. 2007;16:1325–31.PubMedCrossRefGoogle Scholar
  12. 12.
    Harrison DE, Harrison DD, Caillet R, Janik TJ, Holland B. Radiographic analysis of lumbar lordosis: centroid, Cobb, TRALL, and Harrison posterior tangent methods. Spine. 2001;26:E235–42.PubMedCrossRefGoogle Scholar
  13. 13.
    Standaert CJ, Herring SA. Spondylolysis: A critical review. Br J Sport Med. 2000;34:415–22.CrossRefGoogle Scholar
  14. 14.
    Roussouly P, Gollogly S, Berthonnaud E, Labelle H, Weidenbaum M. Sagittal alignment of the spine and pelvis in the presence of L5–S1 isthmic lysis and low-grade spondylolisthesis. Spine. 2006;31:2484–90.PubMedCrossRefGoogle Scholar
  15. 15.
    Murrie VL, Dixon AK, Hollingworth W, Wilson H, Doyle TAC. Lumbar lordosis: Study of patients with and without low back pain. Clin Anat. 2003;16:144–7.PubMedCrossRefGoogle Scholar
  16. 16.
    Giglio CA, Volpon JB. Development and evaluation of thoracic kyphosis and lumbar lordosis during growth. J Child Orthop. 2007;1:187–93.PubMedCrossRefGoogle Scholar

Copyright information

© ISS 2011

Authors and Affiliations

  • William G. Bugg
    • 1
    Email author
  • Mark Lewis
    • 1
  • Arne Juette
    • 1
  • John G. Cahir
    • 1
  • Andoni P. Toms
    • 1
  1. 1.Norwich Radiology AcademyCotman CentreNorwichUnited Kingdom

Personalised recommendations