Three RCTs (n=226) and five observational studies (n=273) were included in the synthesis. Two of the observational studies were retrospective, two were prospective and one was a chart review. RCTs scored between 50 and 56 for quality and observational studies scored between 28 and 48.
Pain relief: All three trials showed positive results for short-term pain relief (less than six months) and two reported positive results for long-term pain relief. Long-term results were not available in the third trial.
The individual observational studies concluded that: patients with radicular symptoms had the best pain relief and in contradiction to those with axial neck pain; 64% of patients had a good or excellent response to a cervical epidural steroid injection; 62% of patients had significant pain relief and 20% had complete relief; 83% had successful pain relief after three months; and 41.4% of patients had excellent pain relief six months post-injection.
Details of complications associated with interlaminar epidural steroid injections were reported in the paper.