A repeated measures analysis of variance showed that subjects receiving treatment with bupivacaine experienced a significant reduction in the numeric rating scale scores compared with those receiving saline at baseline ( M = @ vs M = @ , P = @ ) , @ minutes ( M = @ vs M = @ , P < @ ) , @ minutes ( M = @ vs M = @ , P < @ ) , and @ hours after treatment ( M = @ vs M = @ , P < @ ) , respectively .