This technique is performed with low temperatures (50–70°) differently from traditional radiofrequency that uses high temperatures (150–200°), obtaining the same results in a shorter time (2–3″ versus 15–17″).

Under fluoroscopic guidance, a thermic coagulator (Perc-D coblation Probe) is introduced into the nucleus pulposus; then a bipolar current is applied on the extremity of the electrode, producing a radiofrequency field that breaks collagen bonds. It creates inside the nucleus “an ionic plasma” containing simple molecules and ionized gas such as O2, H2, and NO that will be removed through the needle used to introduce the electrode. The warmth produced does not exceed 70°, and it has a limited diffusion of 2 mm, creating a canal of thermic lesion in the nucleus pulposus. By a manual 360° rotation of the probe for 6 times, without any other movements of in-outside, the system creates six canals of thermic lesion with a rapid dehydration of the nucleus and reduction of disc volume of about 10–20 %. The following contraction of the collagen fibers allows the reduction of the protruded portion with decompression of the compressed root (Fig. 2a–b).

Essential condition is the integrity of the fibrous annulus; otherwise, the mechanism of retraction cannot happen. Best indication is the symptomatic herniated but not extruded disc.

Results obtained from control trials report the resolution of pain symptoms in 70–80 % of cases with duration of pain relief for at least 6 months.

The risk of complications is very low. Principal complications are discitis, anterior disc perforation caused by probe, and cauda equina syndrome.

The aim of this technique is to remove the nucleus pulposus.

A discogram is suggested.

The dekompressor probe (Stryker, Kalamazoo, MI, USA) is introduced through the coaxial 17 gauge trocar into the nucleus pulposus. The trocar can be curved manually if the access is difficult, especially when the herniated disc is at level L5–S1. After switching on the rotating engine, the probe is moved forward and backward, removing and removing tissue (Fig. 3a–d).

The procedure is complete when there is no more material to extract or when the radiologist feels obtaining a satisfactory decompression.

The lumbar percutaneous discectomy dekompressor can be performed under CT or fluoroscopic guidance, without technique limitations; however, if it is performed by fluoroscopic guidance with the patient in the prone position, a posterolateral approach is needed to arrive into the disc using the lateral foramen as the landmark.

The location of the hernia is the most important parameter for the efficacy of therapy. The indications are central or posterolateral and foraminal or extraforaminal herniated disc. The reduction of symptoms is over 70 in 79 % of foraminal posterolateral or extraforaminal hernia.

This technique offers many advantages:

Removing 3 cm of disc material resulted in a significant pressure decrease on the peripheral disc portion, resolving the disc-radicular conflict.

Success is achieved in 70–79 % of cases.

Three cases of broken probe have been reported.

Ozone is an unstable, colorless, irritating gas, with a thorny smell, oxidative power, and antiseptic, disinfectant, and antiviral properties. It is prepared and used in real time, transforming a small percentage of O2 to O3 by special generators. The mixture O2-O3 is injected in the intradiscal space and in the foramen: 3–4 mL in the disc and 10 mL in the foramen. The administrated dose for treating the disc is 30–40 μm/mL, and it is resulted to be the best concentration to dehydrate the nucleus and to reduce the inflammation.

The rationale is that the pain is due to mechanical compression on the root with associated inflammatory changes in periganglionic and periradicular spaces.

With the patient in the prone position, the technique is usually performed under CT for better evaluation of gas distribution into the disc or periganglionic space.

The technique can be performed also by fluoroscopic guidance with control of the intradiscal or canal gas distribution.

A needle is inserted in the nucleus pulposus (18–20 gauge calibre and 7–10 cm length) by oblique paravertebral approach using as target the specific articular facet (Fig. 4a–c). Sometimes, especially at the L5–S1 level, when the “classic” oblique approach might be difficult for anatomical reasons, a further needle inclination of 30° is necessary in the craniocaudal direction, to reach the specific disc space, or a translaminar medial approach should be performed without fear of crossing the dural sac to reach the vertebral disc (Figs. 5a–d and 6a–c).

The needle is placed in the center of the disc and the gas mixture is slowly injected in the nucleus pulposus, then into the epidural and intraforaminal space with a local anti-inflammatory effect.

Extruded herniated disc or free herniated fragments are contraindications.

Discography is not needed because it adds no diagnostic information necessary for the treatment and may affect the impact of the ozone gas.

The oxygen-ozone mechanisms of action have been investigated and include:

No damage is reported if the O2-O3 goes into the CSF or subarachnoid space.

The success rate is reported in 70–80 % of cases.

No early or late neurological or infectious complications have been reported following O2-O3 injection.

A recent meta-analysis about the effectiveness and safety of ozone treatments for herniated lumbar discs shows that pain and function outcomes are similar to the outcomes for lumbar discs treated with surgical discectomy, but the complication rate is much lower (<0.1 %) and the recovery time is significantly shorter.

It is formed by a sterile viscous solution containing 96 % pure ethyl alcohol (a cellulose derivative product) added to a radiopaque element – tungsten – that when injected into the vertebral disc at the cervical or lumbar level produces a local necrosis of the nucleus pulposus. Its action is mechanical via dehydration of the turgescent and protruding disc, which is compressing the peripheral nerves of the cord, causing extreme pain.

After asepsis and local anesthesia, the product is injected into the nucleus pulposus under CT or fluoroscopic guide with post-lateral approach for thoracic or lumbar level and anterolateral approach at for the cervical level.

Preferably the disc is punctured using a small needle of:

The quantity of jellified ethyl alcohol injected varies between 0.2 and 0.8 mL, according to the dimension of the disc and extent of the hernia.

It is recommended to use: