Changes of Compound Muscle Action Potential in Short-term Steroid Therapy for Compression Injury of Rat Sciatic Nerve

Kim, So Hyun; Park, Kwang Won; Baek, Joon Seok; Jung, Tae Young; Kim, Mee Lee; Park, Sang Jun

Abstract

PURPOSE
Many surgical procedures in oral and maxillofacial area can induce trauma to the peripheral nerve. The aim of the study is to evaluate the effects of short-term steroid therapy on nerve recovery after crush injury.
METHODS
Sixteen rats were randomly divided into two groups. The right sciatic nerves were exposed, crushed, and sutured. The control group was not given steroids. The test group was injected with dexamethasone disodium phosphate (2 mg/kg body weight/day) for 7 days. In all animals, compound muscle action potential (CMAP) was recorded before and at 1, 7, 14, 21, and 28 days after injury.
RESULTS
The amplitude of the CMAP before and at 1, 7, 14, 21, and 28 days after injury were 53.20+/-4.80 mV, 20.12+/-5.38 mV, 30.01+/-14.15 mV, 31.14+/-13.56 mV, 31.73+/-16.33 mV, and 37.23+/-16.98 mV in the control group, and 55.25+/-6.72 mV, 18.62+/-6.26 mV, 29.50+/-13.06 mV, 32.90+/-13.226 mV, 30.17+/-11.80 mV, and 38.41+/-12.27 mV in the test group, respectively. The nerve conduction velocity was 18.82+/-3.94 m/s, 16.73+/-3.48 m/s, 19.60+/-2.45 m/s, 18.68+/-3.94 m/s, 18.02+/-3.51 m/s, and 19.25+/-3.88 m/s in the control group, and 18.94+/-3.48 m/s, 17.28+/-2.53 m/s, 17.57+/-2.54 m/s, 18.77+/-2.12 m/s, 19.48+/-1.55 m/s, and 19.22+/-2.97 m/s in the test group, respectively. There was no significant difference between both groups (P>0.05).
CONCLUSION
This study did not show any therapeutic effect of short-term administration of steroids on injured rat sciatic nerve. Further studies are needed.