Clinical trial NCT02210052: Safety of Spine Radiofrequency Procedures
Official title: Safety of Lumbar Spine Radiofrequency Procedures in the Presence of Posterior Pedicle Screws: A Prospective Trial
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Radiofrequency Ablation in Patients With Spinal Hardware
Keywords: radiofrequency ablation
Lead sponsor: Mayo Clinic
Sponsor class: OTHER
First posted: 2014-08-06
Enrollment: 6
Sex: ALL
Minimum age (years): 18
Maximum age (years): 100
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NA
Intervention model: SINGLE_GROUP
Primary purpose: SCREENING

Brief summary: The goal of the study was to determine if patients undergoing radiofrequency neurotomy (RFN) of lumbar facet joints that are adjacent to previously placed pedicle screws from a fusion, would lead to an increase in the temperature of the pedicle screws.

Detailed description: This study was a prospective clinical trial, examining outcomes related to temperature increases in pedicle screws. It was not possible to blind the investigators or the patient. Outcomes related temperature differences were collected at each pedicle screw adjacent to a zygapophyseal joint being treated.

A conventional 18-gauge, 1-cm curved active tip radiofrequency cannula was placed under fluoroscopic guidance to the area to be treated (the junction of the transverse process and the superior articulating process of the facet joint). This position placed the tip of the radiofrequency cannula immediately adjacent to, but not in direct contact with, the pedicle screws. The radiofrequency cannula was connected to a radiofrequency generator, and the conventional settings for clinical medial branch neurotomy was used, heating the tissue to 80°C for 90 seconds. The procedure described up to this point is the normal procedure and protocol for RFN performed at the Mayo Clinic.

The experimental portion of the procedure is as follows: A separate 22 gauge radiofrequency cannula was intentionally placed in direct contact with the dorsal surface of the pedicle screws and was connected to a radiofrequency generator solely for the purpose of measuring temperature, as the RF cannula are dual purpose probes capable of both conducting energy for the radiofrequency lesion and monitoring tissue temperature. In other words, this small gauge needle was placed for the sole purpose of acting as a thermistor probe/temperature monitor. This process was repeated for each level necessary for treatment.

Eligibility criteria: Inclusion Criteria:

- Scheduled for Radiofrequency procedure AND has spinal hardware placed from a previous spinal surgery

Exclusion Criteria:

* Active infection over skin where needle will be placed
* Coagulopathy
* Pregnancy

Primary outcomes:
measure: Number of Procedures in Which Temperature of Screws Increased
timeFrame: 2 hours
Secondary outcomes:
Other outcomes:
Locations:
city: Rochester
country: United States
facility: Mayo Clinic
state: Minnesota
Study officials:
affiliation: Mayo Clinic
name: Tim J Lamer, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Gazelka HM, Welch TL, Nassr A, Lamer TJ. Safety of lumbar spine radiofrequency procedures in the presence of posterior pedicle screws: technical report of a cadaver study. Pain Med. 2015 May;16(5):877-80. doi: 10.1111/pme.12678. Epub 2015 Jan 8.
citation: Lamer TJ, Smith J, Hoelzer BC, Mauck WD, Qu W, Gazelka HM. Safety of Lumbar Spine Radiofrequency Procedures in Patients Who Have Posterior Spinal Hardware. Pain Med. 2016 Sep;17(9):1634-7. doi: 10.1093/pm/pnv078. Epub 2016 Jan 13.