Fifty-two patients with persistent postoperative pain after total knee arthroplasty (TKA) were randomized to receive either percutaneous peripheral nerve stimulation (PNS) (n=28) or placebo (sham stimulation) (n=24). The primary outcome of interest was the proportion of subjects experiencing a ≥50% reduction in average pain intensity during weeks five to eight. Secondary outcomes included functional improvement (6-minute walk test [6MWT] and Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC]), quality of life (Patient Global Impression of Change [PGIC]), and medication usage. Outcomes were assessed up to three months, with ongoing follow-up to 12 months. Overall, the study revealed that 60% of patients in the PNS group achieved ≥50% pain relief compared to 24% in the placebo group. The PNS group also demonstrated significantly greater improvement in walking distance (+47% vs. −9%; p=0.048) and functional scores. These findings suggest that percutaneous PNS effectively reduces persistent postoperative pain and improves function in patients after TKA.