COMPLICATION RATE ASSOCIATED WITH FACET JOINT RADIOFREQUENCY DENERVATION PROCEDURES

Craig A. Kornick, M.D., S. Scott Kramarich, M.D., B. Todd Sitzman, M.D., M.P.H., Kenneth A. Marshall, M.D., Juan Santiago‐Palma, M.D., Tim J. Lamer, M.D. Division of Pain Management, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL 32224 Introduction: Radiofrequency (RF) neural lesioning, also known as RF denervation or neurotomy, is a widely utilized treatment for chronic cervical, thoracic and lumbar facet joint‐related back pain. Major complications are rare when facet joint RF neural lesioning protocols are strictly adhered to. The objective of this study was to determine the complication rate associated with facet joint RF neural lesioning in patients undergoing these procedures at Mayo Clinic Jacksonville. Methods: Following Mayo Clinic IRB approval, complete data were collected using a retrospective chart review of all patients undergoing facet joint RF denervation procedures over a five‐year period (1996–2001). All RF lesions were performed using a RFG‐3CF Lesion Generator (Radionics, Inc.; Burlington, MA), utilizing a standardized lesioning protocol. An insulated 22G, 10 cm Sluijter‐Mehta cannula with a 5‐mm active tip (SMK‐C10; Radionics, Inc.) was placed near the anatomic target site (i.e., medial branch nerve of the dorsal primary ramus innervating the target facet joint) using fluoroscopic guidance. The RF electrode (Radionics SMK‐TC) was then inserted. When sensory stimulation (up to 1 volt at 50 Hz) and motor stimulation (up to 5 volts at 2 Hz) failed to produce nerve root‐mediated sensory and motor manifestations, RF lesioning (80°C for 90 seconds) was performed. Post‐procedural assessment was routinely performed through telephone follow‐up in 3 to 5 days and a scheduled return visit in 4 to 6 weeks. Data were recorded in a computerized data base and included: patient demographics, RF denervation level, total number of RF lesions per patient, date of first return visit, and presence of RF complication, if any. Types of complications recorded included: local pain (including myofascial, symptomatic hematoma, non‐neuritic) at RF site> 1 week duration, neuritic pain < 2 weeks, neuritic pain> 2 weeks, infection, new motor deficit, and new sensory deficit. The chart of every patient with post‐RF complaints was reviewed and adjudicated by a panel of four physicians before being classified as a complication. Descriptive statistical analysis was performed and reported as mean ± standard deviation and percentages. Results: A total of 629 RF denervation lesions, involving 122 separate operative procedures, were performed on 95 patients. Mean patient age was 66 ± 13 years, with 54% female. Each patient received on average 5 ± 3 RF lesions per operative procedure (range 2 to 16). Facet joint spinal levels involved were primarily lumbar (95%), followed by cervical (3%) and thoracic (2%). Mean return visit follow‐up was at 36 days. A total of 10 complications were noted among 8 separate operative procedures, yielding an overall complication rate of 6.5% per operative procedure. Complications included: 2 cases of neuritic‐type pain lasting < 2 weeks, 5 with neuritic‐type pain at RF site lasting> 2 weeks, 2 with prolonged localized pain (non‐neuritic), and 1 with prolonged muscle spasm at the RF operative site. There were no reports of infection, new sensory deficits, or new motor deficits. Conclusion: Facet joint RF denervation procedures, when performed using appropriate lesioning protocol techniques, are associated with a 6.5% minor complication rate.