BACKGROUND: Percutaneous cervical nucleoplasty (PCN) is a safe and effective treatment in symptomatic patients with contained cervical herniated disks. It provides simple and efficient disk decompression, using a controlled and highly localized ablation, but evidence regarding long-term efficacy is limited. We conducted a retrospective study to investigate the long-term efficacy and safety of PCN, and the influence of ideal selection settings. METHODS: A total of 27 patients treated with PCN fulfilling ideal selection criteria (Group A) were studied and compared to 42 patients not meeting these criteria (Group B). Outcomes were assessed using the Visual Analogue Scale (VAS) and a four-level Likert item for perceived pain and satisfaction, the Neck Disability Index (NDI), and the Short Form 36 (SF-36). Additional relevant outcomes were retrieved from medical records. RESULTS: The postoperative mean VAS pain for Group A was 29.9 (SD +/- 32.6) at a mean follow-up of 24 months (range: 2-45). Only 10% of these patients reported mild transient adverse events. There was a trend, but no difference between both groups in pain scores; however, treatment satisfaction was higher for Group A (74.1 +/- 27.2-55.5 +/- 31.4, P = 0.02). Group A also reported better physical functioning based on the Physical Component Summary (43.6 +/- 10.6-37.3 +/- 12.0, P = 0.03) and showed a larger proportion of patients no longer using any medication postoperatively (63-26%, P = 0.01). CONCLUSION: These results show long-term effectiveness and safety of PCN in patients with a one-level contained cervical herniated disk, and the reliance of selecting patients meeting ideal criteria for successful PCN.