The Investigators have designed this exploratory study in patients suffering from zygapophysial joint mediated pain to investigate if a correlation exists between inter-individual genetic variability (genotype) with treatment response (phenotype). More specifically, the investigators aim to identify any form of correlation between a specific SNP of the BDNF gene (Val66Met) and the effectiveness and/or duration of radiofrequency facet joint neurotomy. The study population is patients suffering from chronic low back pain who have been scheduled for radiofrequency neurotomy following the diagnosis of facet joint mediated pain (using medial branch block test). The investigators will evaluate if a common variant of BDNF gene (Val66Met) can be directly correlated to a significant degree of pain relief following RF treatment, and whether the result of such a procedure can be predicted from a specific genetic profile.
Name: Lumbar Radiofrequency Medial Branch Neurolysis
Description: Numerous studies have concluded that facet joint pain can be accurately diagnosed if a significant (but temporary) reduction in pain is achieved with a procedure called a Medial Branch Block (MBB). The clinician delivers a targeted injection of local anesthetic to the joint itself, or in close proximity to the medial branch of the posterior rami of the dorsal root. A significant decrease in pain confirms that the pain originates from the facet joint. If or when the pain returns after successful MBB treatment the patient may be considered for radiofrequency denervation (neurotomy) which selectively disrupts the joint's nerve supply and provides longer-term sustained reliefType: ProcedureChronic Low Back Pain (Lumbar Facet Joints Mediated Pain)
Description: Number of patients in each group who report 50% reduction in pain on the visual analogue scale 3 months after radiofrequency denervation for lumbar zygapophysial (facet) joint mediated pain
Measure: Responder Rate Time: 3 monthsDescription: To evaluate whether any specific and/or combination of SNPs observed could be related with the clinical outcomes measured in this study
Measure: Pre-specified Single Nucleotide Polymorphism (SNP) analysis Time: 3 monthsCohort
There is one SNP
Does the Brain-derived Neurotrophic Factor Val66Met Gene Polymorphism Predict Inter-individual Variation in Responsiveness Following Lumbar Radiofrequency Denervation? --- Val66Met ---
More specifically, the investigators aim to identify any form of correlation between a specific SNP of the BDNF gene (Val66Met) and the effectiveness and/or duration of radiofrequency facet joint neurotomy. --- Val66Met ---
The investigators will evaluate if a common variant of BDNF gene (Val66Met) can be directly correlated to a significant degree of pain relief following RF treatment, and whether the result of such a procedure can be predicted from a specific genetic profile. --- Val66Met ---