Adequate reliability of spinal displacement analysis on sagittal cervical radiographs is essential for chiropractors to use Xray for the detection and quantification of the biomechanical component of subluxation in clinical practice. Sufficient reproducibility of radiographic imaging (patient positioning, equipment positioning, etc.) of the spine is necessary to have scientific validity of the biomechanical component of subluxation. Non-reproducible methods of obtaining X-rays for this analysis could lead to unreliable measurements, incorrect care, and invalid measures of clinical outcomes. This project is a systematic review of the literature that will methodically explore the state of literature and collate the literature on the repeatability of obtaining sagittal spine radiographs.

Grant Value: $12,240
Chief Investigator: Dr Joe Betz & Dr Deed Harrison – Chiropractic BioPhysics® NonProfit.
Status: Ongoing

Clinical Applications:

The available evidence suggests that test–retest reliability of patient positioning and production of the lateral cervical radiograph is likely to be good to excellent. This level of reproducibility supports the clinical use of chiropractic techniques that depend on lateral cervical imaging for subluxation analysis.

Researcher Update:

  • January 2026
    The team is pleased to report that, after securing a highly qualified librarian with expertise in systematic review search strategies, the PubMed search has been completed and abstracts have been collected for the first screening stage. The grey literature search has been finished, and full‑text articles are now being gathered for the second screening stage, positioning the project for strong progress moving forward.
  • June 2025
    The search strategy and design are underway with input from an independent third-party librarian scientist. Database-specific beta testing has been completed, and refinements are ongoing to enhance search accuracy. A grey literature search is being conducted in parallel, with results to be compared against electronic database findings. 

Presentations:

  • 47th Chiropractic Bio Physics Annual Conference August 2025. Arizona, USA
    Reliability of the Biomechanical Assessment of the Sagittal Lumbar Spine and Pelvis on Radiographs