Special Tests: Upper Cervical Spine Stability and Vertebrobasilar Insufficiency (VBI)

by Brent Brookbush DPT, PT, COMT, MS, PES, CES, CSCS, ACSM H/FS

For an introduction to Special Tests including definitions of specific terminology, what special tests measure, how we chose the tests in these lessons, and best use, check out:

Special Tests Covered in this Lesson:


The special tests for upper cervical spine instability and vertebrobasilar ischemia (VBI) are under studied. Many questions are unanswered regarding the reliability, specificity, sensitivity and validity of these tests. Based on the criteria described in Special Tests: Introduction some of these tests would not be included in this course; however, some organizations have called for these tests to be mandatory for the pre-screening of any patient who will receive high velocity cervical manipulations as part of a treatment plan (10, 11).

  • The argument in favor of using these tests is focused on the potentially serious consequences of upper cervical instability and VBI, and the few documented cases of serious complications post cervical manipulation. It should be noted that the tests in this course demonstrate high specificity, based on limited research (4 - 9), and are recommended when subjective complaints infer that VBI or upper cervical instability may be an issue (e.g. myelopathy). Most clinicians would agree that identification of upper cervical instability and VBI in patients complaining of related symptoms is essential. However, the relationship between these symptoms and complications from cervical manipulations has been greatly exaggerated by some professionals.
  • A large survey study by Margarey