Key messages
• Nucleoplasty may greatly reduce neck/arm pain caused by a herniated disk, but may have little to no effect on neck function or quality of life compared to conservative treatment after three months.
• We do not know whether nucleoplasty has any effect on pain, neck function, quality of life or recovery, compared to pulsed radiofrequency (a treatment that uses small bursts of electrical energy to target nerves and reduce pain) or surgery.
• For all treatments, no serious unwanted, harmful effects were reported.
What is disc herniation in the neck?
Discs are soft cushions between the bones of the spine. Disc herniation is when a disc in the neck bulges or slips out of place. This can lead to a nerve in the neck being pinched or irritated, which in turn leads to pain. The pain can spread from the neck down into the shoulder, arm or hand. People might also feel numbness, tingling or weakness in those areas. This type of pain is usually caused by normal wear and tear as we age, but it can also happen after an injury.
How is disc herniation in the neck treated?
Pain due to disc herniation can be managed with conservative treatment, such as rest, pain medication, physiotherapy, cervical collar (a soft or hard neck brace that wraps around your neck to support your head and keep your neck still), or a combination of these. If conservative treatment fails and pain persists, minimally invasive treatment or surgery can be considered.
Nucleoplasty is a minimally invasive procedure in which small portions of the disc's gel-like nucleus are removed to relieve pressure on the surrounding nerves. The procedure is done using local anaesthesia (to numb the area) and is guided by X-ray for accuracy. Temporary side effects of the procedure may include problems with swallowing, headache, muscle stiffness and neck pain. In rare cases, more serious complications may happen, such as damage to the food pipe (oesophagus), injury to blood vessels in the neck or serious nerve damage.
What did we want to find out?
We wanted to find out if nucleoplasty is better than placebo (sham or 'dummy' treatment), conservative treatment, surgery, or pulsed radiofrequency at reducing people's arm/neck pain, improving neck function and other outcomes.
What did we do?
We looked for studies that compared nucleoplasty to placebo, no treatment, conservative treatment, non-surgical interventions and surgery. We compared and summarised the results of the studies and rated our confidence in the evidence, based on factors such as study methods and sizes.
What did we find?
We found four studies involving 259 people with neck pain due to disc herniation. All participants were between 16 and 65 years old. They were treated in a hospital or a clinic. Researchers tracked participants' progress for three to 12 months after treatment. The studies compared nucleoplasty to:
• conservative treatment (one study, 120 participants);
• pulsed radiofrequency (one study, 34 participants);
• surgery (two studies, 105 participants).
Main results
Compared with conservative treatment, one study with 120 people found that nucleoplasty:
• may greatly reduce pain at short-term (3-month) follow-up;
• may result in little to no difference in neck-related function;
• may result in little to no difference in quality of life.
The study assessing conservative treatment reported that none of the participants in either group had any harmful, unwanted events. It did not report on people's recovery time. No one withdrew from the study.
We do not know whether nucleoplasty has any effect on pain, function or recovery compared to pulsed radiofrequency because there was only one study with very few people.
We do not know whether nucleoplasty has any effect on pain, function, quality of life or recovery compared to surgery because there were only two small studies.
Harms
For all treatments, no serious unwanted, harmful effects were reported. Mild, temporary side effects in the nucleoplasty group included problems with swallowing. In the group receiving pulsed radiofrequency, some people experienced headaches and muscle stiffness after treatment. In the surgical group, some people experienced temporary complications directly related to the operation, such as neck pain.
What are the limitations of the evidence?
We had little or no confidence in the evidence for all outcomes because the studies were poorly conducted, had too few people, or provided incomplete information about outcomes.
How current is this evidence?
The evidence is current to 24 February 2025.
Read the full abstract
Cervical radicular pain due to disc herniation presents with pain in the neck and one arm, with muscle weakness with or without numbness or tingling in the fingers or hands. Conservative treatment includes rest, analgesics, non-steroidal anti-inflammatory drugs, exercises and cervical collar. When conservative treatment fails, surgery is considered. Surgery can carry risks, and freedom from pain is not guaranteed. Recently, nucleoplasty, a new treatment for contained disc herniations, was developed. Nucleoplasty is a minimally invasive outpatient procedure that relieves nerve pressure by removing small portions of the disc’s gel-like nucleus, with no reported neurological complications.
Objectives
To assess the effect of nucleoplasty on pain, function, quality of life, recovery, adverse events and withdrawals due to adverse events compared to placebo, no treatment, conservative treatment, minimally invasive interventions or surgery for people with cervical radicular pain due to disc herniation.
Search strategy
We used CENTRAL, MEDLINE, seven other databases and two trial registers, together with reference checking, citation searching and contact with study authors and experts in the field to identify the studies that are included in the review. The latest search date was 24 February 2025.
Selection criteria
We included randomised controlled trials (RCTs) that investigated nucleoplasty compared to placebo/sham treatment, no treatment, conservative treatment, minimally-invasive interventions or surgery for people with cervical radicular pain due to disc herniation. Major outcomes were pain in the arm and neck, neck-related function, recovery, quality of life, adverse events and withdrawals due to adverse events. The primary time point was short-term follow-up (up to three months).
Data collection and analysis
Two review authors independently screened the references. We used the original Cochrane risk of bias tool for RCTs to assess the risk of bias of the included studies. We used GRADE to assess the certainty of the evidence.
Main results
We included four RCTs (259 participants). We judged all four studies to have an overall high risk of bias, due either to a high risk of detection or attrition bias. Three of four studies were at high risk of detection bias for unblinded outcome assessors.
Nucleoplasty versus no treatment or placebo
We did not find any RCT for this comparison.
Nucleoplasty versus conservative treatment (1 study, 120 participants)
Low-certainty evidence, downgraded for risk of bias and imprecision, showed that nucleoplasty may result in a large reduction in pain (0 to 100 scale, 0 = no pain) at short-term follow-up. The mean change from baseline in pain was 30.45 points lower with conservative treatment and 53.16 points lower with nucleoplasty (mean difference (MD) 22.71 points lower (95% confidence interval (CI) 30.10 lower to 15.32 lower)).
Low-certainty evidence, downgraded for risk of bias and imprecision, showed that nucleoplasty may result in no difference in neck-related function at short-term follow-up (Neck Disability Index (NDI) 0 to 50, lower scores indicate less disability). The mean change from baseline function was 9.27 points lower in the conservative treatment group and 11.75 points lower in the nucleoplasty group (MD 2.48 lower, 95% CI 5.11 lower to 0.15 higher).
Low-certainty evidence, downgraded for risk of bias and imprecision, showed that, compared to conservative treatment, nucleoplasty may result in little to no difference in quality of life (36-item Short-Form Health Survey, mental component summary (SF-36 MCS), 0 to 100, 100 = best score) in the short term. The mean change in quality of life from baseline was 8.04 points with conservative treatment and 6.31 points with nucleoplasty (MD 1.73 lower, 95% CI 5.32 lower to 1.86 higher).
Compared to conservative treatment, it is uncertain if nucleoplasty increases the risk of adverse effects. This study did not report on recovery and there were no withdrawals.
Nucleoplasty versus pulsed radiofrequency of the dorsal root ganglion (1 study, 34 participants)
We are uncertain if, compared to pulsed radiofrequency, nucleoplasty has any effect on pain (0 to 100 scale, 0 = no pain; MD 7.9 lower, 95% CI 29.45 lower to 13.65 higher), neck-related function (0 to 50, 0 = best score; MD 0.30 higher, 95% CI 6.97 lower to 7.57 higher), recovery (MD 5.10 lower, 95% CI 29.92 lower to 19.72 higher) or adverse events (risk ratio (RR) 1.0, 95% CI 0.17 to 5.83) at short-term follow-up, due to very low-certainty evidence (downgraded for risk of bias, imprecision and indirectness).
Nucleoplasty versus discectomy (2 studies, 105 participants)
Low-certainty evidence, downgraded for risk of bias and imprecision, showed that nucleoplasty may result in little to no difference in neck pain at short-term follow-up (MD 0.33 points higher, 95% CI 0.36 lower to 1.03 higher). We are uncertain if nucleoplasty has any effect on arm pain (MD 0.74 points lower, 95% CI 1.23 lower to 0.25 lower), neck-related function (MD 0.69 points lower, 95% CI 12.63 lower to 11.25 higher), recovery (RR 0.81, 95% CI 0.51 to 1.29; 1 RCT, 48 participants), quality of life (MD 0.83 points higher, 95% CI 8.47 lower to 10.13 higher; 1 RCT, 48 participants) or adverse events (RR 0.14, 95% CI 0.01 to 2.62) compared to discectomy at short-term follow-up, due to very low-certainty evidence downgraded for risk of bias, imprecision and indirectness. No withdrawals due to adverse events were reported.
Authors' conclusions
Compared to conservative treatment, low-certainty evidence showed that nucleoplasty may result in a large reduction in pain and no difference in neck-related function at short-term follow-up. For the other comparisons (pulsed radiofrequency of the dorsal root ganglion, discectomy), there was low to very low-certainty evidence for little to no effect of nucleoplasty on pain, neck-related function, recovery or adverse events. No serious complications occurred in the nucleoplasty or comparison groups. There is insufficient evidence to support the use of nucleoplasty for people with radicular pain due to disc herniation. There is a need for sufficiently powered, well-designed RCTs.
