Responsiveness of leg alignment changes associated with articular pressure testing to spinal manipulation: the use of a randomized clinical trial design to evaluate a diagnostic test with a dichotomous outcome.
OBJECTIVE
A study was undertaken to assess the stability of leg alignment reaction to a pressure challenge and its responsiveness to an adjustive intervention.


METHODS
Prospective, double-blind clinical trial of a diagnostic test.


METHODS
Laboratory: Center for Technique Research.


METHODS
Forty-two chiropractic college students, faculty and staff.


METHODS
A high-velocity, low-amplitude, short lever adjustment of a single vertebra from among C1 and T3-T7; or a sham adjustment similar to a manual diagnostic pressure test at C1, T3-T7 or T9-T10.


METHODS
Leg alignment reactivity: An increase in leg alignment discrepancy (yes or no) following a metered pressure challenge to a vertebra.


RESULTS
On average, stability was poor at T3-T7 (Kappa = 0.04), moderate at C1 (K = 0.47), and fair for sham pressure tests (K = 0.30). Responsiveness: The proportion of positive baseline leg alignment reactions that responded (became negative) to sham adjustment was 95% at T3-T7 and 55% at C1. Further analysis was untenable since too few vertebrae were implicated for an adjustment.


CONCLUSIONS
For the population investigated, the majority of the responsiveness of the leg alignment diagnostic test to a rotatory adjustment appears to be a diagnostic illusion (i.e., background noise unrelated to a treatment intervention). Further research with different subject populations, regions of investigation, leg alignment measurement techniques and vertebral challenge techniques are indicated.
Haas
M
M
Research Department, Western States Chiropractic College, Portland, OR 97230.
Peterson
D
D
Rothman
E H
EH
Panzer
D
D
Krein
R
R
Johansen
R
R
Solomon
S
S
D000328:Adult; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007866:Leg / Q000473:pathology*; D008297:Male; D008349:Manipulation, Orthopedic / Q000379:methods / Q000592:standards*; D008365:Manometry; D008875:Middle Aged; D011312:Pressure; D011446:Prospective Studies; D012107:Research Design; D013122:Spinal Diseases / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology / Q000628:therapy