CESI With Low Dose Lidocaine and Transient Weakness

Overview

Cervical radicular pain is relatively common, often treated with epidural steroid injection (ESI), when conservative treatments like oral analgesics, physical therapy and activity modification have failed. There are no universal clinical practice guidelines for the use of diluents when CESI are performed. Interlaminar CESI may be performed with or without the use of local anesthetics, due to training bias or theoretical concerns of weakness. CESI without the benefit of local anesthetic as a steroid diluent increases the latency of pain relief and may decrease diagnostic information immediately after a CESI with regard to pain generators responsible for symptoms, and may potentially decrease patient satisfaction. By evaluating the effects of local anesthetic as a diluent during interlaminar cervical ESI, we will enhance the safety of this treatment with regard to expectations of objective motor weakness as well as post procedure pain control and patient satisfaction in the recovery phase after the injection procedure. Research Question: Does lidocaine versus saline as a steroid diluent effect objective upper extremity strength following cervical epidural steroid injection in patients being treated for cervical radiculitis? Null Hypothesis: Cervical epidural steroid injections that include local anesthetic as a diluent have no effect on objective upper extremity strength following the injection. We hypothesized that cervical epidural lidocaine will cause an objective decrease in strength in functional movements of the upper extremity.

Experimental Groups: Prospective, randomized, controlled, double blinded trial in patients undergoing CESI for symptoms of cervical radiculitis. Group #1: Interlaminar cervical ESI at the C7-T1 level with triamcinolone 80 mg + 2 mL 1% lidocaine (total volume 4 cc). Group #2: Interlaminar cervical ESI at the C7-T1 level with triamcinolone 80 mg + 2 mL preservative saline (total volume 4 cc). Adults who are eligible to have a CESI with triamcinolone for treatment of cervical radiculitis at the Northwestern Anesthesiology Pain Medicine Center will be approached by authorized research personnel prior to a patient's CESI is performed and will obtain informed consent from patients who agree to participate. In every subject (Group 1 and Group 2) a pre-procedure NRS pain score, and presence of subjective or objective symptoms of UE weakness will be recorded. Bilateral handgrip, wrist extension, elbow flexion, and elbow extension strength (myotomes C5-T1) will be measured by a trained research assistant prior to the injection procedure using a handheld JAMAR® PLUS+ digital dynamometer (Sammons Preston, Bollingbrook, IL) for hand grip strength and a push/pull handheld hydraulic dynamometer (Balego and Associates Inc., St. Paul, MN) for arm strength assessment. Three baseline strength measurements will be recorded for each strength test. Measurements will be taken prior to and 30 minutes following the injection procedure. Patients in Group #1 and Group #2 will also be queried with the Upper Extremity Functional Index (UEFI) before the injection procedure and again 1 day after the procedure (administered via telephone). For Group 1 and Group 2, patients will be randomized to treatment group based on a random computer-generated schedule. Participants will be blinded to the group to which they are randomized. All standard procedures for CESIs will be followed as is standard practice including time out, skin prep, hemodynamic monitoring, image guidance etc. Per randomization, triamcinolone acetonide 80 mg (Kenalog) (E. R. Squibb \& Sons Limited, Uxbridge UK) will be combined with 2mL Lidocaine 1% or 2 mL preservative free saline and will be injected during the CESI procedure. In all cases, the total injectate volume will be 4 mL in all cases. All injections will be image guided with fluoroscopy, as is the current standard practice. Fluoroscopy time will be recorded. The participant will be discharged from the clinic with written discharge instructions (current standard practice). Participants will be telephoned by clinic personnel 1 day after the CESI to assess for subjective weakness in the hands or arms as well as any other adverse reactions. As above, the Upper Extremity Functional Index will be administered at this time.