Abstract
M.Tech. (Chiropractic)
The study evaluated any changes in serum p-endorphin levels before and after a
chiropractic adjustment and mobilisation ofthe cervical spine.
Three groups of male and female subjects were randomly assigned; the chiropractic group, mobilisation group and detuned ultrasound (control group). Each group consisted of 10 subjects, aged between 18 to 35 with equal numbers of males and females. All subjects were mentally and physically healthy, and were instructed to refrain from nicotine and caffeine intake at least one hour prior to the experiment, as these substances are stimulants and may influence the results.
The research protocol involved having blood taken five minutes before the treatment, and
repeated five minutes after the treatment. The experimental group received bilateral cervical spine adjustments. The mobilisation group under-went cervical spine mobilisation with oscillatory motion, but no thrust was included. The control group had detuned ultrasound applied to their posterior cervical and trapezius muscles. Blood samples were taken by venipuncture and the p-endorphin levels were analysed using immunoenzymometric assay technique.
The results of this study demonstrated that a decrease in p-endorphin levels occurred post intervention in the spinal adjustment group. The mobilisation and detuned ultrasound groups both experienced an increase in p-endorphin levels, but the increase was not statistically significant. This finding allows us to hypothesize that the pain-relieving effects of the chiropractic adjustment, may not be due to a release of p-endorphins, but may be due to the analgesic effect of another system that is not opiate mediated.