Ultrasound-guided percutaneous peripheral nerve stimulation for chronic refractory neuropathic pain: a unique series.

During the last two decades, with the advent of recent technology, peripheral nerve stimulation has become an appealing modality at the forefront of pain management. In this case series, we document the clinical rationale and technical considerations on three of the most challenging cases, refractory to previous interventions, that were treated by our team with an ultrasound-guided percutaneous peripheral nerve stimulator targeting the musculocutaneous, bilateral greater occipital and subcostal nerves. At the 6-month follow-up, all patients experienced greater than 50% relief of baseline pain, with a near-complete resolution of pain exacerbations. Furthermore, to our knowledge, this is the first report of an ultrasound-guided percutaneous technique of a peripheral nerve stimulator targeting the musculocutaneous and subcostal nerves.

Peripheral nerve stimulation is a new tool used in the treatment of peripheral nerve pain. In this study, we share our experience using this technology in three unusual, difficult-to-treat chronic nerve pain presentations, targeting the musculocutaneous, bilateral greater occipital and subcostal nerves. All patients were asked about how pain levels had changed since the peripheral nerve stimulation device had been implanted. In every case, patients reported a decline in their pain level from day one. After 6 months of peripheral nerve stimulator use, all patients reported a greater than 50% pain relief.

Revisiting the Genicular Nerve Block: An Up-to-Date Guide Utilizing Ultrasound Guidance and Peripheral Nerve Stimulation - Anatomy Description and Technique Standardization.

BACKGROUND: Over the last decade, several authors have reported that percutaneous peripheral nerve stimulation (PNS) can be used to assist in verifying the position of the procedure needle tip in relation to nerve structures, and that the combined technique using both ultrasound (US) guidance and PNS may serve as a reliable method for confirmation of the correct position of the procedure needle tip. It has also been reported that, when combined with US guidance, PNS may increase the success rate of pain management interventions. OBJECTIVES: The aim of this technical report was to standardize an effective and easy to learn illustrated step-by-step technical approach to nerve identification during US-guided genicular nerve blocks, using percutaneous PNS as a verification instrument for procedure needle tip location. STUDY DESIGN: This technical protocol was developed based on the results of the authors' most recent cadaveric study on the innervation of the knee joint capsule. The technique was developed and tested by 4 different interventionists with different levels of expertise in US-guided procedures. SETTING: The cadaveric study of the knee joint capsule innervation was performed at the laboratory of the Division of Anatomy of one institution. The technical protocol using US and PNS was later developed at the medical simulation center of a different institution. METHODS: A team of anatomists from a division of anatomy of one institution performed the cadaveric study on the innervation of the knee joint capsule. A team of physicians then developed the step-by-step approach to this technical protocol at the medical simulation center of  a different institution. Finally, the illustrated step-by-step approach was tested by 4 different interventionists with different levels of expertise in US-guided procedures (1 beginner-level user; 1 intermediate-level user; 2 expert-level users), using a portable percutaneous PNS and 2 different US transducers at 2 different institutions. RESULTS: This technical protocol was successfully developed based on the results of the cadaveric study on the innervation of the knee joint capsule. Additionally, it was later successfully tested by interventionists with various levels of expertise utilizing different US equipment at separate institutions. LIMITATIONS: By combining US and nerve stimulation, this protocol requires the availability of both US equipment and necessary equipment for nerve stimulation that must all be made available in the sterile field. Another potential disadvantage is that nerve stimulation controls and the US image screen are generally located on 2 separate display panels, which could cause difficulty with visualization and simultaneous calibration for 2 individual devices. CONCLUSIONS: Our illustrated step-by-step technical protocol can be effectively and safely utilized as a reliable method of training, by which physicians with little to moderate US experience can improve their skills in accurately identifying the genicular nerves while performing US-guided examinations with the intent of executing a peripheral nerve block.

Ultrasound-Guided Percutaneous Peripheral Nerve Stimulation for the Treatment of Chronic Intractable Pain Originating From a Lipofibromatous Hamartoma of the Median Nerve.

This case report presents an application of peripheral nerve stimulation to the median nerve to treat a patient with intractable pain due to a lipofibromatous hamartoma of the left upper extremity. Ultra high-frequency ultrasound was used to determine the boundaries of the hamartoma. The patient then underwent an ultrasound-guided implantation of 2 stimulator electrodes distal to the elbow along the median nerve with stimulation coverage achieved at 1.2 and 1.4 mA, respectively. After an uneventful procedure, the pain score immediately decreased from 9 out of 10 to less than 6 on a numeric rating scale. Two weeks after the procedure, the patient reported substantial pain relief, with an average pain level of 5 to 6 out of 10. Twelve months after implantation, the patient maintained significant pain relief, rating her average pain level as a 4 to 6 out of 10. Placement of a percutaneous peripheral nerve stimulator was safe and effective with no adverse events being reported at the 12-month follow-up.

Ultrasound-Guided Percutaneous Peripheral Nerve Stimulation for the Treatment of Lower Extremity Pain: A Rare Case Report.

OBJECTIVE: This case report presents an application of percutaneous peripheral nerve stimulation to the right superficial peroneal nerve to treat a patient with chronic intractable L5-S1 radiculopathy pain that conventional treatment failed to ameliorate. METHODS: The patient underwent an uneventful implantation of a percutaneous peripheral nerve stimulator. The implanted lead (15 cm in length and 1.2 mm in diameter) containing the receiver coil and 3 stimulation electrodes (Bioness Stimrouter® , Valencia, CA, U.S.A.) was implanted parallel with the trajectory of the right superficial peroneal nerve. RESULTS: Two weeks after implantation of the percutaneous peripheral nerve stimulator, the patient experienced excellent pain relief and reported a significant increase in mobility. At the 3-month follow-up consultation, the patient reported maintenance of the reduction of pain in his right lower extremity as well as improved performance in his daily activities. CONCLUSION: Percutaneous peripheral nerve stimulation offers an alternative treatment option for intractable pain associated with chronic radiculopathy, especially for patients in whom conventional treatment options have been exhausted. Further clinical series involving larger numbers of patients are warranted in order to assess the definitive role of percutaneous peripheral nerve stimulation for the treatment of chronic intractable radiculopathy pain.

Interscalene brachial plexus catheter versus single-shot interscalene block with periarticular local infiltration analgesia for shoulder arthroplasty.

BACKGROUND: Interscalene brachial plexus block is a commonly employed regional anesthetic technique for total shoulder arthroplasty, and a continuous catheter is often placed to extend the analgesic benefit of the block. As periarticular local infiltration analgesia (LIA) for total joint arthroplasty is a re-emerging trend, we evaluated the analgesic efficacy of continuous interscalene block (CISB) compared to single-shot interscalene block (SSISB) with LIA. METHODS: We conducted a retrospective review of 130 consecutive patients treated by one surgeon in a single institution, with 12 patients excluded for history of chronic opioid tolerance and two for incomplete data. The SSISB with LIA treatment group (N.=53) was compared to a control group who received CISB (N.=63). Primary end points were a difference in pain score (0-10 numeric rating scale) and opioid requirements as oral morphine equivalents (OMEs) on postoperative days (PODs) 0 and 1. Secondary end points included nausea and vomiting, length of hospital stay, block failure rate, adverse events due to block, and 30-day readmission. RESULTS: When compared to SSISB with LIA, patients who received CISB exhibited decreased opioid requirements in OMEs on POD 0 (11.9 mg vs. 28.7 mg, P<0.01) and POD 1 (24.0 mg vs. 50.3 mg, P<0.01). There was no significant difference in pain on POD 0, but a statistically significant decrease in average pain scores with CISB on POD 1 (2.3 vs. 4.3, P<0.01). CONCLUSIONS: SSISB with LIA may provide clinically similar postoperative analgesia compared to CISB, but with escalating doses of opioid requirements.