Procedural Pain During Lumbar Medial Branch Blocks With and Without Skin Wheal Anesthesia: A Prospective Comparative Observational Study.

OBJECTIVE: To determine if skin wheals reduce procedural pain associated with lumbar medial branch blocks (MBBs) performed with 25-gauge needles. DESIGN: Prospective comparative observational study. SETTING: Outpatient Physical Medicine & Rehabilitation and interventional pain practice within an academic tertiary care center. SUBJECTS: Ninety-nine consecutive patients who underwent lumbar MBBs for facet pain were included. Patients who were obese or required larger-diameter needles were excluded. METHODS: One to three facet joints were targeted per side, with some patients receiving bilateral procedures. All injections were performed with 25-gauge, 3.5-inch Quincke tip needles under fluoroscopic guidance. A total of 306 needle sticks were recorded. MBBs were performed without skin wheals or any other type of local anesthesia (35 patients, 108 needle sticks), with skin wheals (30 patients, 94 needle sticks), and in mixed groups (34 patients, 47 needle sticks with skin wheals, 57 needle sticks without skin wheals or other type of local anesthesia). Patients rated the pain of each needle placement immediately after the multilevel MBB procedure. RESULTS: Considering all 306 needle sticks, needles that were placed using skin wheals caused slightly more pain than those placed without skin wheals or any other type of local anesthesia (P = 0.007). CONCLUSIONS: Skin wheals do not reduce and may increase procedural pain associated with lumbar MBBs performed with 25-gauge needles.

The Impact of Local Steroid Administration on the Incidence of Neuritis following Lumbar Facet Radiofrequency Neurotomy.

BACKGROUND: Pain arising from the lumbar facet joints is a common cause of axial back pain in adults. Radiofrequency neurotomy (RFN) of the medial branches of the spinal dorsal rami has been used as a treatment option. The most common side effect is transient, localized, burning, neuritic-type pain, termed post-neurotomy neuritis (PNN). Corticosteroids have been administered through the radiofrequency cannula after neurotomy to prevent PNN, but no study has examined the effects of this on PNN. OBJECTIVES: We investigated the incidence of PNN in patients who received corticosteroids after RFN and in those patients who did not receive corticosteroids. STUDY DESIGN: Retrospective evaluation. SETTING: Single-site interventional pain management practice in an urban tertiary academic medical center. METHODS: One hundred and sixty-four patients were included in this study and were categorized into non-steroid (n = 87) and steroid (n = 77) groups. Patient's age, gender, body mass index (BMI), laterality of procedure, use of neuropathic pain medications, baseline pain, and duration of pain were all recorded. PNN was determined if the patient self-reported transient burning or neuropathic pain at the site prior to or at the 6-week routine follow-up encounter. RESULTS: There was no significant difference in demographic characteristics between the 2 groups in age, gender, baseline pain, and duration of pain. The proportion of patients in the steroid treated group with PNN was 5 out of 77 (6.4%) and the non-steroid group was 6 out of 87 (6.9%). There was no statistically significant difference between the groups. There was no statistically significant difference in the incidence in neuritis between individuals taking neuropathic agents and individuals not taking neuropathic agents. LIMITATIONS: This study has several limitations including small sample size, patients' self-reported neuropathic symptoms, and inability to draw strong conclusions due to the retrospective study design. A single interventionalist performed all the procedures in this retrospective study and variations in technique amongst others are inevitable. CONCLUSION: Administration of steroids after RFN does not reduce the incidence of post-neurotomy neuritis. Concurrently administering neuropathic medications does not protect against neuritis. KEY WORDS: Radiofrequency neurotomy, radiofrequency ablation, neuritis, corticosteroid, lumbar facet pain, post neurotomy neuritis.