The Effect of Percutaneous Nucleoplasty vs Anterior Discectomy in Patients with Cervical Radicular Pain due to a Single-Level Contained Soft-Disc Herniation: A Randomized Controlled Trial

Background: Cervical radicular pain (CRP) is a common problem in the adult population. When conservative treatment fails and the severe pain persist, surgical treatment is considered. However, surgery is associated with some serious risks. To reduce these risks, new minimally invasive techniques have been developed, such as percutaneous nucleoplasty. Several studies have shown that percutaneous nucleoplasty is a safe and effective technique for the treatment of CRP, but until now no randomized controlled trials have been conducted that compare percutaneous cervical nucleoplasty (PCN) to anterior cervical discectomy (ACD) in patients with a single-level contained soft-disc herniation.

Objectives: To compare the effects of PCN and ACD in a group of patients with CRP caused by a single-level contained soft-disc herniation.

Study design: A randomized, controlled, multi-center trial.

Setting: Medical University Center and local hospitals.

Methods: Forty-eight patients with CRP as a result of a single-level contained soft-disc herniation were randomized to one of the following 2 treatments: PCN or ACD. The primary outcome measure was arm pain intensity, measured with a Visual Analog Scale (VAS). Secondary outcomes were arm pain intensity during heavy effort, neck pain, global perceived effect, Neck Disability Index (NDI), and the patients' general health (Short Form Generated Health Survey [SF-36]). All parameters were measured at baseline (T0), 3 months after intervention (T2), and one year after intervention (T3). One week after the intervention (T1), an intermediate assessment of arm pain, arm pain during heavy effort, neck pain, satisfaction, and improvement were performed.

Results: At 3 months, the intention to treat analyses revealed a statistical significant interaction between the groups on the primary outcome, arm pain intensity, and on the secondary outcome of the SF-36 item pain, in favor of the ACD group. On the other secondary outcomes, no statistical significant differences were found between the groups over time. At 12 months, there was a trend for more improvement of arm pain in favor of the ACD group and no statistical interactions were found on the secondary outcomes.

Limitations: Firstly, the inclusion by the participating hospitals was limited. Secondly, the trial was ended before reaching the required sample size. Thirdly, at baseline, after the inclusion by the neurosurgeon, 13 patients scored less than 50.0 mm on the VAS. Fourthly, the withdrawal of the physiotherapy (PT) group and finally, the patients and interventionists could not be blinded for the treatment.

Conclusions: At 3 months, the ACD group performed significantly better on arm pain reduction than the PCN group in patients with CRP as a result of a single-level contained soft-disc hernia. However, the clinical relevancy of this treatment effect can be debated. For all parameters, after one year, no significant differences between the groups were found. When it comes to the longer-term effectiveness, we conclude that PCN can be a good alternative for ACD.