Four RCTs (n=335 patients, sample size from 47 to 152) were included, with Detsky quality scores between 13 to 18 points. Anterior ulnar nerve transposition was compared with simple decompression. In two trials the submuscular approach was employed (n=117 patients) and in two the subcutaneous method (n=218 patients).
Three trials (n=261 patients) reported a clinical score as an outcome and there were no significant differences between simple decompression and anterior transposition, yielding an effect size of -0.04 (95% Confidence Interval (CI): -0.36 to 0.28; p=not significant).
Two trials (n=100 patients) reported postoperative motor nerve conduction velocities, with an effect size of 0.24 (95% CI: -0.15 to 0.63; p=not significant).
There was no significant heterogeneity between studies. Funnel plots were uninformative.