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Objective. High frequency (HF) block can quickly and reversibly stop nerve conduction. We hypothesized HF block at the sciatic nerve would minimize nociception by preventing neuropathic signals from reaching the central nervous system. Approach. Lewis rats were implanted with a constriction cuff and a distal cuff electrode around their right sciatic nerve. Tactile sensitivity was evaluated using the 50% paw withdrawal threshold (PWT) determined using Chaplan’s method for von Frey monofilaments. Over the course of 49 d, the 50% PWT was measured (1) before HF block, (2) during HF block (50 kHz, 3 V pp), and (3) after HF block. Gait was observed and scored before and during block. At end point, HF block efficacy was directly evaluated using additional cuff electrodes to elicit and record compound neural action potentials across the HF blocking cuff. Main results. At days 7 and 14 d post-operation, tactile sensitivity was significantly lower during HF block compared to before and after block (p< 0.005). Additionally, an increase in gait disability was not visually observed during HF block. Significance. HF block can reduce tactile sensitivity in a limb with a neuropthic injury in a rapidly reversible fashion.

Occupational health nurses play a key role in evaluating innovative technologies that can aid in providing safe and rapid care and reduce lost work time. A nurse-led employee health clinic participated in a validation study of a novel pathogen detection technique developed by GeneCapture, Inc. Their proposed portable urinary tract infection (UTI) in vitro diagnostic test was challenged with discarded, deidentified urine samples from patients presenting with typical UTI symptoms collected at two university clinics and two multiphysician practices. GeneCapture’s panel for this study was designed to rapidly identify the genetic signature of seven organisms: gram-negative Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, and Pseudomonas aeruginosa; gram-positive Enterococcus faecalis and Staphylococcus aureus; and fungal Candida species. The results from 40 clinical samples were in 95% agreement (90% specificity, 100% sensitivity) with traditional urine culture results from routine analysis. This successful occupational health nursing collaboration and validation study shows promise for point-of-care diagnoses and earlier treatment for workers with UTIs.

Background The purpose of this study was to evaluate if kilohertz frequency alternating current (KHFAC) stimulation of peripheral nerve could serve as a treatment for lumbar radiculopathy. Prior work shows that KHFAC stimulation can treat sciatica resulting from chronic sciatic nerve constriction. Here, we evaluate if KHFAC stimulation is also beneficial in a more physiologic model of low back pain which mimics nucleus pulposus (NP) impingement of a lumbar dorsal root ganglion (DRG). Methods To mimic a lumbar radiculopathy, autologous tail NP was harvested and placed upon the right L5 nerve root and DRG. During the same surgery, a cuff electrode was implanted around the sciatic nerve with wires routed to a headcap for delivery of KHFAC stimulation. Male Lewis rats (3 mo., n = 18) were separated into 3 groups: NP injury + KHFAC stimulation (n = 7), NP injury + sham cuff (n = 6), and sham injury + sham cuff (n = 5). Prior to surgery and for 2 weeks following surgery, animal tactile sensitivity, gait, and static weight bearing were evaluated. Results KHFAC stimulation of the sciatic nerve decreased behavioral evidence of pain and disability. Without KHFAC stimulation, injured animals had heightened tactile sensitivity compared to baseline (p < 0.05), with tactile allodynia reversed during KHFAC stimulation (p < 0.01). Midfoot flexion during locomotion was decreased after injury but improved with KHFAC stimulation (p < 0.05). Animals also placed more weight on their injured limb when KHFAC stimulation was applied (p < 0.05). Electrophysiology measurements at end point showed decreased, but not blocked, compound nerve action potentials with KHFAC stimulation (p < 0.05). Conclusions KHFAC stimulation decreases hypersensitivity but does not cause additional gait compensations. This supports the idea that KHFAC stimulation applied to a peripheral nerve may be able to treat chronic pain resulting from sciatic nerve root inflammation.

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