Ultrasound-Guided Thermocoagulation of Medial Nerve Branch in Lumbar Facet Joints Pain.

Ultrasound-Guided Thermocoagulation of Medial Nerve Branch in Lumbar Facet Joints Pain. Effectiveness and Benefits of a Non Irradiating Technique.

We propose here to evaluate the precision of lumbar thermocoagulation performed under a transverse ultrasound approach by performing a fluoroscopic control once the needle in the desired position. The effectiveness of the technique will be assessed by measuring different pain and disability scores at six weeks post-thermocoagulation: the Visual analogue pain Scale score (VAS) and the Oswestry disability score (ODI) will be collected, compared to that of the conventional fluoroscopic technique.

Low back pain affects 70 to 80% of people at least once in their lives. They have considerable socio-economic repercussions and represent the leading medical cause of work stoppage, at around 25% .1 The articular pain between the lumbar vertebrae, called facet joints pain, represent between 15 and 45% of all low back pain and their manifestations are grouped under the name of facet syndrome including localized pains at the lumbar level as well as pains referred to the gluteal, trochanteric, inguinal and lateral and posterior region of the thigh. 2-5 The thermocoagulation of the roots innervating the lumbar facets consists in creating a lesion of the nerve roots innervating these articulations in order to block the transmission of the pain. According to many studies this technique gives good results in 70 to 80% of the cases with an improvement around 71% to more than six months. 6 A recent Meta-analysis involving 454 patients also shows a significant improvement at 12 months of thermocoagulation versus placebo and even versus epidural lumbar. 7 To date, Lumbar Thermocoagulation are still mostly performed under fluoroscopic control by injection of contrast. This technique have proved this effectiveness, but have significant disadvantages, such as the irradiation of the patient as well as that of the practitioner because of the number of daily acts performed and its cost. For its part, ultrasound is easily available, easy to use, represents a lower cost, and the lack of irradiation. The technique to reach the lumbar facet joints with sonography is pretty well described and known for many years. 8 We propose here to evaluate the precision of lumbar thermocoagulation performed under a transverse ultrasound approach by performing a fluoroscopic control once the needle in the desired position. The effectiveness of the technique will be assessed by measuring different pain and disability scores at six weeks post-thermocoagulation: the Visual analogue pain Scale score (VAS) and the Oswestry disability score (ODI) will be collected, compared to that of the conventional fluoroscopic technique.

Prone position: Thanks to a high-resolution ultrasound and a 5 MHz curved probe, we will use the ultrasound technique described by Greher et al to reach the target points. Then, in order to check the correct positioning of the needles, we will inject 1 ml of a solution of contrast medium (omnipaque® 300 mg / ml of Iohexol) to observe them using the standard Fluoroscopic method. Wrongly positioned needles will be correctly repositioned and these patients will be excluded from ODI and VAS scale statistics.

Prone position: We will use the standard fluoroscopic method to reach the target points. (maximum three levels, same side). Then, in order to check the correct positioning of the needles, we will inject 1 ml of a solution of contrast medium (omnipaque® 300 mg / ml of Iohexol). The correct location being the superolateral edge of the lateral facet and the diffusion of the contrast material at the level of the medial branch observed thanks to an anteroposterior radioscopic view. Then the location of the needles is confirmed by a lateral radioscopic view.

Prone position: Thanks to a high-resolution ultrasound and a 5 MHz curved probe, we will use the ultrasound technique described by Greher et al to reach the target points. Then, in order to check the correct positioning of the needles, we will inject 1 ml of a solution of contrast medium (omnipaque® 300 mg / ml of Iohexol) to observe them using the standard Fluoroscopic method. Wrongly positioned needles will be correctly repositioned and these patients will be excluded from ODI and VAS scale statistics. To ensure the effectiveness of the injury by thermocoagulation, sensory electrical stimulation is performed to confirm that the needle is close to the posterior ramus (50Hz, 0-3 volts) and another electrical stimulation is performed to confirm that there is no motor stimulation (2Hz, 0-3 volts). After injecting 1 ml of 2% linisol® through the needle, denervation of the facet will be performed with an electrode at 68 ° C for 90 seconds.

Prone position: We will use the standard fluoroscopic method to reach the target points. (maximum three levels, same side). Then, in order to check the correct positioning of the needles, we will inject 1 ml of a solution of contrast medium (omnipaque® 300 mg / ml of Iohexol). The correct location being the superolateral edge of the lateral facet and the diffusion of the contrast material at the level of the medial branch observed thanks to an anteroposterior radioscopic view. Then the location of the needles is confirmed by a lateral radioscopic view. To ensure the effectiveness of the injury by thermocoagulation, sensory electrical stimulation is performed to confirm that it is close to the posterior ramus (50Hz, 0-3 volts) and another electrical stimulation is performed to confirm that there is no motor stimulation (2Hz, 0-3 volts). After injecting 1 ml of 2% linisol® through the needle, denervation of the facet will be performed with an electrode at 68 ° C for 90 seconds.

Inclusion Criteria: Over the age of 18. Facet Syndrome. Symptomatology superior than 3 mounths. A failure of conservative treatement (drugs, physiotherapy...) Partial improvement after two lumbar facet infiltrations. Exclusion Criteria: Allergy to any of the constituents of the infiltrated product, or to the contrast medium Unstable medical condition: cardiac, respiratory, endocrine (uncontrolled diabetes) Local infection (cutaneous, perimedullary / spinal) or systemic. Coagulopathy (platelets <50000 / mm3, Prothrombin time <60%, INTernational normalized ratio> 1.5), anticoagulant or antiplatelet therapy treatment other than aspirin. Lumbar arthrodesis. Neurological condition affecting motor function (Stroke, Parkinson...) Pregnant woman.

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Lee CH, Chung CK, Kim CH. The efficacy of conventional radiofrequency denervation in patients with chronic low back pain originating from the facet joints: a meta-analysis of randomized controlled trials. Spine J. 2017 Nov;17(11):1770-1780. doi: 10.1016/j.spinee.2017.05.006. Epub 2017 May 30.

Greher M, Scharbert G, Kamolz LP, Beck H, Gustorff B, Kirchmair L, Kapral S. Ultrasound-guided lumbar facet nerve block: a sonoanatomic study of a new methodologic approach. Anesthesiology. 2004 May;100(5):1242-8. doi: 10.1097/00000542-200405000-00028.

Jung H, Jeon S, Ahn S, Kim M, Choi Y. The validation of ultrasound-guided lumbar facet nerve blocks as confirmed by fluoroscopy. Asian Spine J. 2012 Sep;6(3):163-7. doi: 10.4184/asj.2012.6.3.163. Epub 2012 Aug 21.

Kim D, Choi D, Kim C, Kim J, Choi Y. Transverse process and needles of medial branch block to facet joint as landmarks for ultrasound-guided selective nerve root block. Clin Orthop Surg. 2013 Mar;5(1):44-8. doi: 10.4055/cios.2013.5.1.44. Epub 2013 Feb 20.