title: Criterion validity of manual assessment of spinal stiffness.
abstract: Assessment of spinal stiffness is widely used by manual therapy practitioners as a part of clinical diagnosis and treatment selection. Although studies have commonly found poor reliability of such procedures, conflicting evidence suggests that assessment of spinal stiffness may help predict response to specific treatments. The current study evaluated the criterion validity of manual assessments of spinal stiffness by comparing them to indentation measurements in patients with low back pain (LBP). As part of a standard examination, an experienced clinician assessed passive accessory spinal stiffness of the L3 vertebrae using posterior to anterior (PA) force on the spinous process of L3 in 50 subjects (54% female, mean (SD) age = 33.0 (12.8) years, BMI = 27.0 (6.0) kg/m(2)) with LBP. A criterion measure of spinal stiffness was performed using mechanized indentation by a blinded second examiner. Results indicated that manual assessments were uncorrelated to criterion measures of stiffness (spearman rho = 0.06, p = 0.67). Similarly, sensitivity and specificity estimates of judgments of hypomobility were low (0.20-0.45) and likelihood ratios were generally not statistically significant. Sensitivity and specificity of judgments of hypermobility were not calculated due to limited prevalence. Additional analysis found that BMI explained 32% of the variance in the criterion measure of stiffness, yet failed to improve the relationship between assessments. Additional studies should investigate whether manual assessment of stiffness relates to other clinical and biomechanical constructs, such as symptom reproduction, angular rotation, quality of motion, or end feel.
authors: U.S. Army-Baylor University Doctoral Program in Physical Therapy, San Antonio, TX, USA. Electronic address: shanekoppenhaver@mac.com.
authors: Shane L
authors: SL
authors: Koppenhaver
authors: School of Psychology and Exercise Science, Murdoch University, Perth, Australia.
authors: Jeffrey J
authors: JJ
authors: Hebert
authors: Department of Physical Therapy, University of Alberta, Alberta, Canada.
authors: Greg N
authors: GN
authors: Kawchuk
authors: Department of Physical Therapy (MSGS/SGCUY), 81st Medical Group, Keesler Air Force Base, Biloxi, MS, USA.
authors: John D
authors: JD
authors: Childs
authors: U.S. Army-Baylor University Doctoral Program in Physical Therapy, San Antonio, TX, USA.
authors: Deydre S
authors: DS
authors: Teyhen
authors: U.S. Army-Baylor University Doctoral Program in Physical Therapy, San Antonio, TX, USA.
authors: Theodore
authors: T
authors: Croy
authors: University of Utah, College of Health, Salt Lake City, UT, USA; Intermountain Health Care, Salt Lake City, UT, USA.
authors: Julie M
authors: JM
authors: Fritz
mesh_terms: D000328:Adult; D001416:Back Pain / Q000503:physiopathology*; D001696:Biomechanical Phenomena; D004185:Disability Evaluation; D005260:Female; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000503:physiopathology; D010147:Pain Measurement; D026741:Physical Therapy Modalities; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013131:Spine / Q000503:physiopathology*
keywords: Low back pain; Manual assessment; Stiffness; Validity