Effectiveness Of Lumbar Medial Branch Blocks With Different Injection Agents In Managing Low Back Pain

Objective:To determine the clinical effectiveness of therapeutic lumbar medial branch blocks(LMBB)with different injection agents in managing low back pain.To evaluate the relevant factors affecting the outcomes.Methods:194 screened patients with low back pain were allocated by injection agents to Group A(lidocaine,diprospan,n=58),Group B(lidocaine,diprospan,methylcobalamin,n=43)and Group C(lidocaine,triamcinolone acetonide,methylcobalamin,n=93).LMBB was performed under the guidance of C-arm.Numeric rating scale(NRS)was measured at baseline,1 day,1 week,2 weeks,1 mouth and 3 mouths.Significant pain relief was described as a ≥50% reduction in the NRS score or NRS≤3.Evaluate the correlated factors affecting the outcomes at 1 day and 3 mouths.Compare the efficacy of three groups.Result:(1)41% of patients received significant pain relief more than 3 mouths,40% of patients received significant pain relief in 1 week to 3 mouths.(2)The pain duration,bilateral difference,surgical institute had no significant effect on the outcome(P>0.05).The injection volume >2ml showed greater effect at 1 day(P<0.05),but had no significant difference at 3 mouths(P>0.05).The patients who had back sprain history showed greater effect at 3 mouths(P<0.05).(3)The difference of NRS at baseline among three groups was not significant(P>0.05).The NRS at 1 day,1 week,2 weeks,1 mouth and 3 mouths was lower significantly compared baseline among three groups(P<0.05).The difference of NRS at 1 day,1 week,2 weeks,1 mouth and 3 mouths between A and B,B and C,A and C were not significant(P>0.05).Conclusion:LMBB is an effective procedure for the treatment of low back pain.The injection volume and back sprain history can affect the outcome.High volume shows greater short-term effect,but equivalent long-term effect.Patients who have back sprain history shows greater long-term effect.Methylcobalamin has no significant effect on outcome.Diprospan and triamcinolone acetonide has no significant difference on outcome.