Ultrasound-guided fascial plane blocks for post-breast surgery pain syndrome.

INTRODUCTION: Persistent pain following breast surgery is common and may be challenging to treat. In patients refractory to conservative treatments, ultrasound-guided fascial plane blocks of thoracic nerves can be a useful option. RESULTS: This type of neuro blockade technique provides advantages in terms of safety and efficacy that are convenient for physicians managing refractory and complex cases of post-breast surgery syndrome. CONCLUSION: This technical review aims to present an up-to-date summary of the most common ultrasound-guided fascial plane blocks for chronic pain in post-breast surgery patients, provide a detailed technical description of each intervention, and propose preferred injections based on the anatomical location of the pain.

Ultrasound-Guided Gluteal Fascial Plane Block for the Treatment of Chronic Refractory Greater Trochanteric Pain Syndrome - Technique Description and Anatomical Correlation Study.

INTRODUCTION: Greater trochanteric pain syndrome may often mimic pain generated from other sources. However, it is most commonly caused by gluteus medius and gluteus minimus tendinopathy or tear. The purpose of this technical report was to: 1) describe the ultrasound-guided fascial plane block technique targeting the superior gluteal nerve in the plane between gluteus medius/gluteus minimus to treat moderate-to-severe, chronic, refractory greater trochanteric pain syndrome; 2) anatomically correlate the procedure with cadaveric dissections demonstrating the structures being imaged and the tissues along the needle trajectory; 3) demonstrate the feasibility of the technique with serial dissection of one cadaveric specimen following injection with color dye. TECHNIQUE DESCRIPTION: The ultrasound-guided fascial plane block targeting the superior gluteal nerve to treat moderate-to-severe, chronic, refractory greater trochanteric pain syndrome has been outlined with supporting ultrasound scans and anatomical dissections. The cadaveric dissections are correlated to the ultrasound scans of a healthy volunteer and provide visualization of the tissues in the needle trajectory. The feasibility study in a cadaveric specimen showed adequate stain of the superior gluteal nerve without spread to the piriformis muscle belly, the sciatic nerve, or the inferior gluteal nerve. CONCLUSIONS: This ultrasound-guided fascial plane block is a feasible option for blocking the superior gluteal nerve without inadvertent involvement of the sciatic and inferior gluteal nerves. Further randomized controlled clinical trials are necessary to assess the clinical efficacy of the gluteus medius/gluteus minimus fascial plane block to treat moderate-to-severe, chronic, refractory greater trochanteric pain syndrome.

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.

Paravertebral block for radiologically inserted gastrostomy tube placement in amyotrophic lateral sclerosis.

INTRODUCTION: Radiologically inserted gastrostomy (RIG) placement in patients with amyotrophic lateral sclerosis (ALS) carries risks related to periprocedural sedation and analgesia. To minimize these risks, we used a paravertebral block (PVB) technique for RIG placement. METHODS: We retrospectively reviewed patients with ALS undergoing RIG placement under PVB between 2013 and 2017. RESULTS: Ninety-nine patients with ALS underwent RIG placement under PVB. Median (range) age was 66 (28 to 86) years, ALS Functional Rating Scale-Revised score was 27 (6 to 45), and forced vital capacity was 47% (8%-79%) at time of RIG placement. Eighty-five (85.9%) patients underwent RIG placement as outpatients, with a mean postanesthesia care unit stay of 2.3 hours. The readmission rate was 4% at both 1 and 30 days postprocedure. DISCUSSION: PVB for RIG placement has a low rate of adverse events and provides effective periprocedural analgesia in patients with ALS, the majority of whom can be treated as outpatients.

Early In-Hospital Pain Control Is a Stronger Predictor for Patients Requiring a Refill of Narcotic Pain Medication Compared to the Amount of Narcotics Given at Discharge.

BACKGROUND: The United States is combating an opioid epidemic. Orthopedic surgeons are the third highest opioid prescribers and therefore have an opportunity and obligation to assist in the efforts to reduce opioid use and abuse. In this article, we evaluate risk factors for patients requiring an opioid refill after primary total knee arthroplasty, with the goal to reduce opioid prescriptions for those patients at low risk of requiring a refill in order to reduce the amount of unused medication. METHODS: We retrospectively reviewed narcotic-naïve patients who underwent total knee arthroplasty from December 2017 to May 2018. We performed multivariable analysis on demographics and preoperative, operative, and postoperative characteristics to determine risk factors for requiring a prescription refill following hospital discharge. RESULTS: One-hundred fifty-seven patients were included in the analysis. Sixty percent of patients required a prescription refill. Risk factors included younger age (P = .003) and increased pain on postoperative day one (P < .001). The amount of narcotic medication given at discharge did not independently affect the refill rate (P = .21). CONCLUSION: There is strong evidence that elderly patients and those with good pain control on postoperative day 1 are at a lower risk of requiring a narcotic refill postoperatively. With this information, physicians may begin to tailor narcotic prescriptions based on patient risk factors for requiring a prescription refill rather than provide patients with the same number of pills for a given surgery in an effort to reduce unused narcotic medication.

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.

ANESTHETIC MANAGEMENT OF FEMORAL FRACTURE REPAIR IN A PATIENT WITH CERVICAL MYELOPATHY, AUTONOMIC DYSFUNCTION, AND DIFFICULT AIRWAY.

Spinal stenosis is a potentially serious condition that can lead to myelopathies and autonomic instability, both of which, as a result, may complicate anesthetic management. Additionally, neuraxial anesthesia appears to increase the risk of worsened neurological outcomes in this population. A 56-year-old female with spinal stenosis, autonomic dysfunction, and known difficult airway who required anesthesia for repair of a femur fracture is presented. After pre-operative arterial line and femoral block placement, an ultrasound guided subarachnoid block was safely placed. This supports the notion that in the appropriate setting, a safe, successful neuraxial blockade can be performed when a general anesthetic may be fraught with more risk.

Lumbar plexus block surface landmarks as assessed by computed axial tomography in adult patients with scoliosis: a case series.

BACKGROUND AND OBJECTIVES: Lumbar plexus (LP) block is a common and useful regional anesthesia technique. Surface landmarks used to identify the LP in patients with healthy spines have been previously described, with the distance from the spinous process (SP) to the skin overlying the LP being approximately two-thirds the distance from the SP to the posterior superior iliac spine (PSIS) (SP-LP:SP-PSIS ratio). In scoliotic patients, rotation of the central neuraxis may make these surface landmarks unreliable, possibly leading to an increased block failure rate and an increased incidence of complications. The objective of the present study was to describe these surface landmarks of the LP in patients with scoliosis. METHODS: We selected 47 patients with known thoracolumbar scoliotic disease from our institution's radiology archives. We measured bony landmark geometry, Cobb angle, and the LP location and depth. Additionally, we calculated the SP-LP:SP-PSIS ratio for both the concave and convex sides. RESULTS: In scoliotic patients (31 females and 16 males), the median (range) Cobb angle was 23 (8-54) degrees. The LP depth was 7.5 (5.7-10.7) cm on the concave side of the scoliotic spine and 7.6 (5.4-10.8) cm on the convex side, while the distance from the SP-LP was 3.4 (1.9-4.7) cm on the concave side and 3.7 (2.4-5.1) cm on the convex side. The SP-LP:SP-PSIS ratio was 0.61 (0.20-0.97) and 0.65 (0.45-0.98) on the concave and convex sides, respectively. None of these distances were significantly different between sides. CONCLUSIONS: In patients with scoliotic disease of the spine, there is wide variability in the bony surface landmarks. The location of the LP is generally more medial than expected when compared with both modified and traditional landmarks. A review of the imaging studies and the pre-procedural ultrasound assessment of the anatomy should be considered prior to needle puncture.

Real-time two-dimensional and three-dimensional echocardiographic imaging of the thoracic spinal cord: a possible new window into the central neuraxis.

Transesophageal echocardiography of the spine has been difficult to perform, and high-quality images have been difficult to obtain with earlier available technology. New capabilities in hardware and software reconstruction may allow more reliable clinical data to be obtained. We describe an initial successful attempt to image the adult spinal canal, its contents, and in situ instrumentation. This report is a retrospective review of two patients in whom transesophageal echocardiography (TEE) was used to image the thoracic spine. The thoracic spine was identified and imaged with real-time 2-D and 3-D technology with location of the thoracic aorta and slight insertion and withdrawal of the TEE probe until the intervertebral discs alignment was optimized. Images of the spinal cord anatomy and its vascular supply, as well as indwelling epidural catheters were easily identified. 2-D and 3-D imaging was performed and images were recorded in digital imaging and communications in medicine format. 3-D reconstruction of images was possible with instantaneous 3-D imaging from multiple 2-D electrocardiogram-gated image acquisitions using the Phillips TEE IE-33 imaging platform. The central neuraxial cavity, including the spinal cord and the spinal nerve roots, was easily visualized, and motion of the cord was seen in a phasic pattern (with respiratory variation); cerebrospinal fluid surrounding the spinal cord was documented. The epidural space and local anesthetic drug administration through the epidural catheter were visualized, with the epidural catheter seen lying adjacent to the epidural tissue as a bright hyperechoic line. Pulsed-wave Doppler determined a biphasic pattern of blood flow in the anterior spinal artery through pulse mapping of the anatomic area. New, advanced imaging hardware and software generate clinically useful imaging of the thoracic spine in 2-D and 3-D using TEE. We believe this technology holds promise for future diagnostic and therapeutic interventions in the operating room that were previously unavailable.

Breast cancer recurrence in patients receiving epidural and paravertebral anesthesia: a retrospective, case-control study.

PURPOSE: Studies have suggested an association between the use of regional paravertebral or epidural anesthesia and a reduction in tumor recurrence following breast cancer surgery. To examine this relationship we performed a retrospective case-control study of patients undergoing breast cancer surgery receiving regional, regional and general, or general anesthesia. METHODS: A retrospective chart review was performed of patients undergoing surgery for stage 0 to III breast cancer. Patients identified as receiving regional anesthesia were then matched for age, stage, estrogen receptor (ER) status, progesterone receptor status, and HER-2 expression with patients who received no regional anesthesia. Univariate (Pearson's χ2 test and odds ratio) and multivariate logistic analyses with backward stepwise regression were performed to determine factors associated with cancer recurrence. RESULTS: Between 1998 and 2007, 816 women underwent surgery for stage 0-III breast cancer at our institution. Forty-five patients developed tumors. Univariate analysis showed the use of regional anesthesia trended towards reduced cancer recurrence, but it did not achieve statistical significance (p = 0.06). Higher recurrence rates were associated with ER positive status (p = 0.003) and higher tumor stage (p < 0.0001). Age and HER-2 status were not associated with increased cancer recurrence (both p > 0.11). Multivariate analysis confirmed ER status and stage as independently influential (p = 0.002 and p < 0.0001 respectively). CONCLUSION: Although we found a trend towards reduced breast cancer recurrence with the use of regional anesthesia, univariate analysis did not reach statistical significance.

Ultrasound-guided procedures for the management of chronic thoracic back pain: a technical review.

Pain arising from the thoracic region has been reported to be potentially as debilitating as cervical or lumbar back pain, and may stem from a vast number of spinal sources, including zygapophysial, costovertebral and costotransverse joints, intervertebral discs, ligaments, fascia, muscles, and nerve roots. Over the last two decades, the use of ultrasound in interventional spinal procedures has been rapidly evolving, due to the ultrasound capabilities of visualizing soft tissues, including muscle layers, pleura, nerves, and blood vessels, allowing for real-time needle tracking, while also reducing radiation exposure to both patient and physician, when compared to traditional fluoroscopy guidance. However, its limitations still preclude it from being the imaging modality of choice for some thoracic spinal procedures, notably epidural (interlaminar and transforaminal approaches) and intradiscal injections. In this technical review, we provide an overview of five thoracic spinal injections that are amenable to ultrasound guidance. We start by discussing their clinical utility, followed by the relevant topographic anatomy, and then provide an illustrated technical description of each of the procedures discussed: (1) erector spinae plane block; (2) intra-articular thoracic zygapophyseal (facet) joint injection; (3) thoracic medial branch block; (4) costotransverse joint injection; and (5) costovertebral joint injection.

Success of ultrasound guided popliteal sciatic nerve catheters is not influenced by nerve stimulation.

BACKGROUND: There is debate as to whether nerve stimulation (NS) is required to place peripheral nerve catheters when using ultrasound (US) guidance. There is conflicting evidence for whether stimulating catheters improve postoperative analgesia compared to non-stimulating catheters. The use of US in combination with NS has been shown to be superior to NS alone in terms of popliteal nerve blockade. Given the previously published reports, we hypothesized that there is improvement in sensory and motor blockade for stimulating popliteal perineural catheters placed under US guidance when NS is used. METHODS: Following IRB approval, 21 patients undergoing elective foot and ankle surgery were randomly assigned to either a US or US+NS-guided continuous popliteal sciatic nerve block using a lateral approach. The primary end-point of the study was successful nerve blockade at 20 minutes. Secondary end-points included: block performance time, minimum stimulating current, pain scores on postoperative day 1 and day 2, and patient satisfaction. RESULTS: There was no significant difference in successful nerve blockade at 20 minutes in the US versus US+NS groups (73% vs. 80%, p = 1). Procedure time was significantly shorter in the US only group (median 62 seconds vs. 130.5 seconds, p < 0.01). Postoperative pain scores and overall patient satisfaction were not significantly different between the two groups. CONCLUSION: We have found that the addition of NS provides no benefit over US alone. US alone was associated with a significantly shorter block performance time. US+NS showed no significant difference in pain control, patient satisfaction, or block success.

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.

Intraoperative Epicardial Ultra-High Frequency Ultrasound in Coronary Artery Bypass Grafting Surgery.

The use of intraoperative epicardial ultrasound in order to aid physicians and surgeons in open cardiac surgery has been established for quite some time. Recently, the development of ultra-high frequency ultrasound (UFHUS), 50-70 megahertz (MHz) technology has resulted in high-resolution imaging capabilities previously unavailable for clinical use. This report is the first to describe the use of intraoperative UFHUS epicoronary scanning to assess coronary anatomy and visualize cardioplegia flow within native coronary vessels.

Autologous Platelet-Rich Plasma Applications in Chronic Pain Medicine: Establishing a Framework for Future Research - A Narrative Review.

BACKGROUND: During the last decades, platelet-rich plasma has been studied for the treatment of multiple chronic pain conditions, in addition to being employed in the enhancement of healing after tissue injury. OBJECTIVE: To establish a framework for future research regarding the utilization of platelet-rich plasma in the treatment of chronic tissue injuries. METHODS: Preclinical and clinical studies from 2000-2020 relevant to applications of platelet-rich plasma for the treatment of chronic pain conditions were extracted from PubMed and Medline databases. The studies were analyzed on the basis of the study population, type of intervention, method of platelet-rich plasma preparation, the number of treatments administered, the timeframe of injections, and clinical outcomes. RESULTS: Although several preclinical studies and double-blind, randomized trials have shown promising results in the application of platelet-rich plasma for the treatment of multiple chronic pain conditions, various studies have also reported controversial results. Additionally, the methods employed for obtaining the platelet-rich plasma have not been standardized between studies, resulting in different concentrations of blood components between the preparations utilized. Moreover, differences between studies were also found regarding the number of injections administered per treatment. CONCLUSIONS: Future research addressing the utilization of platelet-rich plasma in the treatment of chronic pain conditions should focus on shedding light on the following major questions: a) Is there a dose-effect relation between the platelet count and the clinical efficacy of the preparation?; b) What pathology determinants should be considered when selecting between leukocyte-enriched and leukocyte-depleted concentrates?; c) What is the role of platelet activation methods on the clinical efficacy of platelet-rich plasma?; d) Is there an optimal number of injections and time frame for application of multiple injection treatment cycles?; e) Does the addition of local anesthetics affect the clinical efficacy of platelet-rich plasma?; and f) Is there potential for future platelet-rich plasma applications for the treatment of neuropathic pain of peripheral origin?

Ultrasound-guided hydrodissection of the superficial peroneal nerve for chronic neuropathic pain: a war veteran's story.

Aim: This case report presents the application of ultrasound-guided hydrodissection of the superficial peroneal nerve to treat chronic refractory neuropathic pain, rated by the patient with an average intensity of 6/10 on the numerical rating scale. Materials & methods: Under ultrasound guidance, the nerve was identified compressed by a herniation of the peroneus brevis. An in-plane hydrodissection was performed using a solution of 10 ml of ropivacaine and methylprednisolone until the epineurium was entirely separated from the surrounding tissue. Results: At the 2-month follow-up, the patient reported a decrease of pain, which he rated a 2/10 on the numerical rating scale. At this point, night-time episodes of moderate pain persisted. The procedure was repeated and at the 6-month follow-up, the patient remained pain free. Conclusion: This case report suggests that consecutive ultrasound-guided hydrodissection techniques might be a valuable option in the treatment of superficial peroneal nerve entrapment neuropathy.

Peripheral neuropathic pain is a debilitating pain condition. Management can be challenging and clinicians often rely on oral medications and surgical options. This case report presents the treatment of a case of longstanding, moderate-to-severe superficial peroneal nerve entrapment neuropathy due to a grenade explosion, with consecutive nerve hydrodissection using a solution containing an anesthetic and a corticosteroid. Immediately after the second procedure and at the 6-month follow-up the patient reported near-total relief.

Application of Color Doppler Ultrasound to Identify and Repair Postoperative Cerebrospinal Fluid Leak: A Technical Note.

BACKGROUND: Incidental durotomy is a known complication of spinal surgery. Persistent cerebrospinal fluid (CSF) leak after unrecognized durotomy may lead to prolonged hospitalization and significant morbidity. If initial bed rest fails, the surgeon must choose between nontargeted methods such as oversewing the wound and lumbar drain placement or return to the operating room. OBJECTIVE: To report the novel use of color flow doppler (CFD) in conjunction with ultrasound (US) to localize the point of CSF leak, assist with aspiration of the pseudomeningocele, and direct the application of fibrin sealant or epidural blood patch. METHODS: This article includes a description of the technique as a technical note. RESULTS: A 72-year-old man underwent L2-5 laminectomies for spinal stenosis. During the index operation, a durotomy occurred and was repaired primarily. The patient subsequently developed leg weakness, back pain, and bulging of the incision. Using CFD, the site of durotomy was determined. Under direct visualization, 34 mL of CSF was aspirated from the pseudomeningocele and 20 mL of fibrin sealant was placed opposing the durotomy. At 2-month follow-up, CFD confirmed absent flow and MRI demonstrated pseudomeningocele resolution. CONCLUSION: This article represents the first report highlighting the utility of CFD US to guide epidural patch placement for postsurgical CSF leaks. CFD allows localization of the durotomy and direct application of blood or fibrin sealant, potentially increasing the success rate of epidural blood patch in postoperative patients. This approach is less invasive than revision surgery and does not require the prolonged hospitalization of lumbar drainage or other nontargeted interventions.

A retrospective case series of prophylactic neurectomy during total knee arthroplasty.

INTRODUCTION: Total knee arthroplasty is a common operation performed to relieve pain and restore functional activity. While overall widely successful, a subset of patients has continued pain postoperatively with no identifiable cause. Neuroma formation has been identified as a possible contributor to this unexplained pain, often necessitating an additional procedure for neuroma removal. The purpose of our study was to evaluate if prophylactic neurectomy could reduce the occurrence of postoperative pain. METHODS: A total of 112 patients were compared, 44 control patients and 68 neurectomy patients. Demographic information, Numerical rating pain scale (NRS) and Knee Society Scores (KSS) were collected pre- and post-operatively. Patients were additional asked if they were overall satisfied with the operation. RESULTS: There were no differences between groups with respect to age (Median: 71 vs 69 years, p = 0.28), male sex (41% vs 44%, p = 0.85), or body mass index (Median: 32.2 vs 31.3, p = 0.80). When comparing the degree of change following surgery there were no statistically significant differences observed in NRS pain scores (Median change: -7 vs -6, p = 0.89) or KSS scores (Median change: +44 vs +40, p = 0.14). Similarly, there was no statistically significant difference in overall patient-reported satisfaction with the knee replacement (82.5% vs 86.6%, p = 0.59). CONCLUSION: We did not find a statistically significant difference in NRS, KSS, or overall patient satisfaction between the prophylactic neurectomy and control patient groups. Larger studies with evaluation of the nerve diameter will be needed to determine which patients are at risk for symptomatic neuroma development following total knee arthroplasty.

Ultrasound-guided diagnostic IPACK as a valuable tool in the management of a patient with soleal sling syndrome: a doubly rare case report.

This article describes the use of an infiltration between the popliteal artery and capsule of the knee joint (IPACK) to diagnose an entrapment neuropathy of the tibial nerve (TN) in a patient presenting with chronic neuropathic pain in the medial posterior compartment of the left knee, with a previous electromyography showing no evidence of tibial or common peroneal nerve neuropathy. After a positive sciatic nerve block, the patient was evaluated for a TN block, cancelled due to the presence of an abnormal leash of vessels wrapping around the nerve. For this reason, the patient was submitted to a diagnostic IPACK. A negative IPACK suggested that a compression of the TN at the popliteal fossa was the most likely source of the symptoms. After surgical decompression of the TN nerve at the popliteal fossa, the patient's symptoms decreased substantially.

Lay abstract This case report describes the use of an infiltration between the popliteal artery and capsule of the knee joint (IPACK), a technique in which local anesthetic is injected between the popliteal artery and the back side of the knee joint, to diagnose a compression of the tibial nerve (TN) in a patient with chronic knee pain. A female adult patient presented for further evaluation of chronic pain in the inner side of the back of her left knee. A previous electromyography showed no evidence of tibial or common peroneal nerve disease. After a positive diagnostic block of the left sciatic nerve, the patient was evaluated for a left TN block, so as to ascertain whether a compression of this nerve at the back side of the knee could be the origin of the patient's symptoms. During the ultrasound scanning of the TN, a group of abnormal vessels was found wrapping around the nerve, which made it impossible to inject the TN in a safe manner, even with the guidance of ultrasound. For this reason, the patient was instead submitted to a diagnostic left IPACK. A negative IPACK suggested that a compression of the TN at the popliteal fossa, the region behind the knee joint, was the most likely source of the patient's symptoms. After surgical decompression of the TN at the popliteal fossa, the patient's symptoms decreased substantially.

A case for ultrasound-guided peripheral nerve stimulation in intractable anterior cutaneous nerve entrapment syndrome.

Aim: This case report documents the use of peripheral nerve stimulation in the setting of entrapment of the anterior cutaneous branches of the intercostal nerves, with pain rated by the patient as severe during exacerbation episodes. Materials & methods: Under ultrasound guidance, two permanent leads were implanted caudad to cephalad, along and superficial to the lateral aspect of the rectus abdominis, distal to the umbilicus (1 lead per side). Results: At the 6 month follow-up, the patient reported near complete resolution of baseline pain, as well as fewer, sporadic pain exacerbation episodes, rated as mild-to-moderate. Conclusion: This case report suggests that peripheral nerve stimulation might be a valuable treatment option for previously intractable abdominal pain due to entrapment of the anterior cutaneous branches.

Anterior cutaneous nerve entrapment syndrome is a peculiar, a largely disregarded pain condition. Current management algorithms rely mostly on local injections followed by surgical anterior neurectomy. This case report presents a case of longstanding, anterior cutaneous nerve entrapment syndrome, unresponsive to first-line treatment, that was successfully treated with peripheral nerve stimulation technology targeting the anterior cutaneous branches.