Quantification of Cavitation and Gapping of Lumbar Zygapophyseal Joints During Spinal Manipulative Therapy

Professor and Dean of Research, Department of Research, National University of Health Sciences, Lombard, IL.
Journal of manipulative and physiological therapeutics (Impact Factor: 1.48). 08/2012; 35(8). DOI: 10.1016/j.jmpt.2012.06.007
Source: PubMed


The purpose of this study was to use previously validated methods to quantify and relate 2 phenomena associated with chiropractic spinal manipulative therapy (SMT): (1) cavitation and (2) the simultaneous gapping (separation) of the lumbar zygapophyseal (Z) joint spaces.

This was a randomized, controlled, mechanistic clinical trial with blinding. Forty healthy participants (18-30 years old) without a history of low-back pain participated. Seven accelerometers were affixed to the skin overlying the spinous processes of L1 to L5 and the S1 and S2 sacral tubercles. Two additional accelerometers were positioned 3 cm left and right lateral to the L4/L5 interspinous space. Participants were randomized into group 1, side-posture SMT (n = 30), or group 2, side-posture positioning (SPP, n = 10). Cavitations were determined by accelerometer recordings during SMT and SPP (left side = upside for both groups); gapping (gapping difference) was determined by the difference between pre- and postintervention magnetic resonance imaging scan joint space measurements. Results of mean gapping differences were compared.

Upside SMT and SPP joints gapped more than downside joints (0.69 vs -0.17 mm, P < .0001). Spinal manipulative therapy upside joints gapped more than SPP upside joints (0.75 vs 0.52 mm, P = .03). Spinal manipulative therapy upside joints gapped more in men than in women (1.01 vs 0.49 mm, P < .002). Overall, joints that cavitated gapped more than those that did not (0.56 vs 0.22 mm, P = .01). No relationship was found between the occurrence of cavitation and gapping with upside joints alone (P = .43).

Zygapophyseal joints receiving chiropractic SMT gapped more than those receiving SPP alone; Z joints of men gapped more than those of women, and cavitation indicated that a joint had gapped but not how much a joint had gapped.

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  • Journal of manipulative and physiological therapeutics 05/2013; 36(4):259. DOI:10.1016/j.jmpt.2013.05.003 · 1.48 Impact Factor
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    Journal of manipulative and physiological therapeutics 06/2013; DOI:10.1016/j.jmpt.2013.05.002 · 1.48 Impact Factor
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