title: Retrospective study of cranial strain pattern prevalence in a healthy population.
abstract: BACKGROUND
  Research studies have associated cranial strain patterns with a variety of neurologic disorders. However, baseline data on the prevalence of such patterns in a healthy population is lacking.
  
  
  OBJECTIVE
  To determine the prevalence of cranial strain patterns in healthy subjects.
  
  
  METHODS
  A retrospective analysis of cranial strain findings from healthy subjects who participated in two previous research projects. Data were collected for the following cranial strain patterns: torsion (left or right), sidebending rotation (left or right), lateral (left or right), and vertical (superior or inferior).
  
  
  RESULTS
  Data from 142 healthy subjects--119 women and 23 men with a mean age of 24.5 years--were analyzed. Torsion and sidebending rotation were the most common cranial strain patterns observed, comprising 72% of all identified patterns. The most prevalent patterns when stratified by the side of dysfunction were right torsion (31%), left sidebending rotation (23%), and left lateral (19%). Left sidebending rotation with right torsion (17%); left lateral, left sidebending rotation, and right torsion (14%); and right sidebending rotation with right torsion (11%) were the most common combinations of cranial stain patterns.
  
  
  CONCLUSIONS
  Although the present study identified common cranial strain patterns in a healthy population, future studies with broader patient populations and multiple observers are needed to confirm and further define these findings.
authors.affiliation: Department of Osteopathic Principles and Practice, Nova Southeastern University College of Osteopathic Medicine, Fort Lauderdale, Florida, USA. timoshki@nsu.nova.edu
authors.forename: Elena M
authors.initials: EM
authors.lastname: Timoshkin
authors.forename: Mark
authors.initials: M
authors.lastname: Sandhouse
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D005431:Florida / Q000453:epidemiology; D019416:Head Movements / Q000502:physiology*; D006801:Humans; D008297:Male; D015995:Prevalence; D016059:Range of Motion, Articular; D012189:Retrospective Studies; D012399:Rotation; D013180:Sprains and Strains / Q000453:epidemiology*; D054159:Torsion, Mechanical; D055815:Young Adult