Disc Volume Reduction with Percutaneous Nucleoplasty in an Animal Model

Abstract

Study DesignWe assessed volume following nucleoplasty disc decompression in lower lumbar spines from cadaveric pigs using 7.1Tesla magnetic resonance imaging (MRI).PurposeTo investigate coblation-induced volume reductions as a possible mechanism underlying nucleoplasty.MethodsWe assessed volume following nucleoplastic disc decompression in pig spines using 7.1-Tesla MRI. Volumetry was performed in lumbar discs of 21 postmortem pigs. A preoperative image data set was obtained, volume was determined, and either disc decompression or placebo therapy was performed in a randomized manner. Group 1 (nucleoplasty group) was treated according to the usual nucleoplasty protocol with coblation current applied to 6 channels for 10 seconds each in an application field of 360°; in group 2 (placebo group) the same procedure was performed but without coblation current. After the procedure, a second data set was generated and volumes calculated and matched with the preoperative measurements in a blinded manner. To analyze the effectiveness of nucleoplasty, volumes between treatment and placebo groups were compared.ResultsThe average preoperative nucleus volume was 0.994 ml (SD: 0.298 ml). In the nucleoplasty group (n = 21) volume was reduced by an average of 0.087 ml (SD: 0.110 ml) or 7.14%. In the placebo group (n = 21) volume was increased by an average of 0.075 ml (SD: 0.075 ml) or 8.94%. The average nucleoplasty-induced volume reduction was 0.162 ml (SD: 0.124 ml) or 16.08%. Volume reduction in lumbar discs was significant in favor of the nucleoplasty group (p<0.0001).ConclusionsOur study demonstrates that nucleoplasty has a volume-reducing effect on the lumbar nucleus pulposus in an animal model. Furthermore, we show the volume reduction to be a coblation effect of nucleoplasty in porcine discs.

Safety and Effectiveness of Transforaminal Epiduroscopic Laser Ablation in Single Level Disc Disease: A Case-Control Study

“…Numerous studies have reported laser ablation with the use of laser as an alternative treatment to spinal surgeries, but the mechanisms of action of laser ablation has not been fully elucidated (2,(8)(9)(10)(11)(12)(13). Studies have shown that the biophysical mechanism of laser involves high-energy ablation which ablates the NP, decreases NP volume, and produces pain relief (7,14,15). A decrease in NP volume may enhance local circulation, whereas an increase in vascular supply stimulates macrophages and migrating macrophages may desiccate the NP.…”

Efficacy of Coblation Annuloplasty in Discogenic Low Back Pain

“…However, more proponents and clinical evidence supported nucleoplasty for individual with lumbar radicular pain, 26 , 27 because of decompression of nerve root through removing nucleus material, decreasing nucleus volume and lowering intradiscal pressure. 28 , 29 In contrast, the benefit of coblation nucleoplasty in treating discogenic low back pain is uncertain, because the scope of interruption of nerves hardly reached to the outer annulus, which was considered as the major origin of discogenic pain. 8 …”

“…The possible explanation is that lowering the tension in the outer annulus is benefit for decompression of nerves innervated the outer annulus. 28 , 29 Additionally, the modification of biochemical state to inhibit inflammatory stimulation to nerves innervated the outer annulus maybe play one therapeutic role in treating discogenic pain. 30 …”

Interventional Therapies for Chronic Low Back Pain

“…The usual general contraindications are the same as for any surgical procedure and include fever, infection, bleeding diathesis, and anticoagulant therapy. Vaporization of nuclear material by creating multiple intradiscal channels during coblation with the device wand should result in reduction of nuclear tissue volume and lead to a decrease in intradiscal pressure that can result in pain reduction. The patient usually does not feel discomfort during the procedure, because the coblation and coagulation take place within the nucleus pulposus, which contains little sensory innervation.…”