Ultrasound imaging and guidance in peripheral nerve entrapment: hydrodissection highlighted

Safety and Efficacy of Ultrasound-Guided Perineural Hydrodissection as a Minimally Invasive Treatment in Carpal Tunnel Syndrome: A Systematic Review

Ultrasound-guided perineural hydrodissection (HD) is a novel technique that has been found to be effective in providing mechanical release of perineural adhesions and decompression of the nerve, reducing inflammation and edema and restoring its physiological function. It has a significant impact on chronic neuropathic pain (20 ± 4 weeks with VAS < 5 or VAS diminished by 2 points after the procedure). Carpal tunnel syndrome (CTS) is a common entrapment mononeuropathy, and its distribution is typically innervated by the median nerve. Patients with mild or moderate CTS may benefit from nonsurgical treatments or conservative therapies. This review was conducted following the preferred reporting items for systematic reviews and meta-analysis (PRISMA) statement guidelines. Four investigators assessed each title, abstract, and full-text article for eligibility, with disagreements being resolved by consensus with two experienced investigators. The qualitative assessment of the studies was carried out using the modified Oxford quality scoring system, also known as the modified Jadad score. Furthermore, risk of possible biases was assessed using the Cochrane collaboration tool. The results of this review suggest that US-guided HD is an innovative, effective, well-tolerated, and safe technique (11 out of 923 patients had collateral or side effects after the procedure). However, further studies comparing all drugs and with a larger sample population are required to determine the most effective substance.

Volume Effect of Nerve Hydrodissection for Carpal Tunnel Syndrome: A Prospective, Randomized, and Single-Blind Study

OBJECTIVES

This study compared ultrasound-guided nerve hydrodissection (HD) outcomes using two commonly used injectate volumes (10 and 5 mL) of normal saline to explore if there is a volume effect of HD for patients with moderate carpal tunnel syndrome (CTS).

METHODS

Twenty-four participants were randomly assigned to treatment with HD using ultrasound-guidance and either 10 mL or 5 mL of normal saline (HD-10 and HD-5 groups respectively). Our primary outcome measures were the change scores of the two subscales of the Boston Carpal Tunnel Syndrome Questionnaire: The Symptom Severity Scale (SSS) and Functional Status Scale (FSS). We conducted a one-way repeated analysis of variance for 3 time points (4, 12, and 24 weeks) for both SSS and FSS, respectively, for change scores from time 0, and percentage change from time 0.

RESULTS

All participants (n = 12 per group) completed the study. From 0 to 24 weeks the HD-10 group outperformed the HD-5 group for improvement in SSS (median ± IQR; -0.8 ± 0.4 versus -0.5 ± 0.5; P = .024) and FSS scores (mean ± SD; -0.8 ± 0.2 versus -0.5 ± 0.5; P = .011). The HD-10 group improvement in FSS subtest significantly exceeded the MCID percentage-change-based threshold of 27% (34%; P = .039).

CONCLUSIONS

Despite the limitations of small study size, a largely inert injectate, and a single injection approach, these findings in favor of the 10 mL group suggest that the volume used for ultrasound-guided HD in moderate CTS matters, and a higher volume is more effective.

Current Insights into Carpal Tunnel Syndrome: Clinical Strategies for Prevention and Treatment

BACKGROUND

Carpal tunnel syndrome (CTS) is a condition that is caused by medial nerve compression, resulting in symptoms such as numbness, tightness, or weakness in the hand.

OBJECTIVES

The aim of the study was to find out the genetic modulation, mechanism, available treatment, and recommendation for carpal tunnel syndrome at its specific stage.

METHODS

Almost 200 papers were searched for this review article, and 145 articles were selected. The literature was collected from different sources like Google scholar, PubMed, a directory of open-access journals, and science.gov by using keywords, such as treatment, risk factors, recommendation, and clinical features of carpal tunnel syndrome.

RESULTS

The most efficient non-surgical treatment is methylprednisolone acetate, which reduces inflammation by acting on the glucocorticoid receptor in conjunction with immunofilling. It has also been used successfully as a second-line drug for the treatment of patients with mild or moderate conditions in order to provide relief. New non-pharmacological options include laser therapy in acupuncture, transcutaneous electric nerve stimulation (TENS), and sham therapy. Modern treatments like TENS, laser therapy, splints, and injections of methylprednisolone acetate have been demonstrated to be helpful in sporadic situations. For patients with mild and moderate problems, more research should be conducted that includes the combination of these surgical and non-surgical treatments.

CONCLUSION

We propose a multifunctional panel construct and define standard data items for future research into carpal tunnel syndrome. A discussion on idiopathic carpal tunnel syndrome, risk factors, combination of therapies, using guidelines-based recommendations and treatment should be initiated.

The Potential of Ultrasound Radiomics in Carpal Tunnel Syndrome Diagnosis: A Systematic Review and Meta-Analysis

Background: Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy for which ultrasound imaging has recently emerged as a valuable diagnostic tool. This meta-analysis aims to investigate the role of ultrasound radiomics in the diagnosis of CTS and compare it with other diagnostic approaches. Methods: We conducted a comprehensive search of electronic databases from inception to September 2023. The included studies were assessed for quality using the Quality Assessment Tool for Diagnostic Accuracy Studies. The primary outcome was the diagnostic performance of ultrasound radiomics compared to radiologist evaluation for diagnosing CTS. Results: Our meta-analysis included five observational studies comprising 840 participants. In the context of radiologist evaluation, the combined statistics for sensitivity, specificity, and diagnostic odds ratio were 0.78 (95% confidence interval (CI), 0.71 to 0.83), 0.72 (95% CI, 0.59 to 0.81), and 9 (95% CI, 5 to 15), respectively. In contrast, the ultrasound radiomics training mode yielded a combined sensitivity of 0.88 (95% CI, 0.85 to 0.91), a specificity of 0.88 (95% CI, 0.84 to 0.92), and a diagnostic odds ratio of 58 (95% CI, 38 to 87). Similarly, the ultrasound radiomics testing mode demonstrated an aggregated sensitivity of 0.85 (95% CI, 0.78 to 0.89), a specificity of 0.80 (95% CI, 0.73 to 0.85), and a diagnostic odds ratio of 22 (95% CI, 12 to 41). Conclusions: In contrast to assessments by radiologists, ultrasound radiomics exhibited superior diagnostic performance in detecting CTS. Furthermore, there was minimal variability in the diagnostic accuracy between the training and testing sets of ultrasound radiomics, highlighting its potential as a robust diagnostic tool in CTS.

Ultrasound Imaging of the Sciatic Nerve

The sciatic nerve (SN) is the biggest nerve in the human body and innervates a large skin surface of the lower limb and several muscles of the thigh, leg, and foot. It originates from the ventral rami of spinal nerves L4 through S3 and contains fibers from both the posterior and anterior divisions of the lumbosacral plexus. After leaving the neural foramina, the nerve roots merge with each other forming a single peripheral nerve that travels within the pelvis and thigh. Non-discogenic pathologies of the SN are largely underdiagnosed entities due to nonspecific clinical tests and poorly described imaging findings. Likewise, to the best of our knowledge, a step-by-step ultrasound protocol to assess the SN is lacking in the pertinent literature. In this sense, the aim of the present manuscript is to describe the normal sono-anatomy of the SN from the greater sciatic foramen to the proximal thigh proposing a standardized and simple sonographic protocol. Then, based on the clinical experience of the authors, a few tips and tricks have been reported to avoid misinterpretation of confounding sonographic findings. Last but not least, we report some common pathological conditions encountered in daily practice with the main purpose of making physicians more confident regarding the sonographic "navigation" of a complex anatomical site and optimizing the diagnosis and management of non-discogenic neuropathies of the SN.

Treatment of posterior interosseous nerve entrapment syndrome with ultrasound-guided hydrodissection: A case report

BACKGROUND

Posterior interosseous nerve (PIN) entrapment syndrome is one of the causes of weakness and pain of the arm muscles, which is prone to missed diagnosis and misdiagnosis in clinic practice. This paper reports a case of PIN entrapment syndrome, with PIN injury indicated by electrophysiology. Musculoskeletal ultrasound was applied to identify that the entrapment point was located at the inlet of the Frohse arch and the outlet of the supinator muscle. Treatment with ultrasound-guided nerve hydrodissection was performed on the entrapment point, which significantly improved the symptoms. Ultrasound-guided nerve hydrodissection is an effective therapeutic method for PIN entrapment syndrome.

CASE SUMMARY

A male patient, 35 years old, worked as an automobile mechanic. He felt slightly weak extension activity of his right fingers 2 years ago but sought no treatment. Later, the symptoms gradually became aggravated and led to finger drop, particularly severe in the right middle finger, accompanied by supination weakness of the right forearm. Neural electrophysiological examination showed that the patient had partial PIN injury of the right radius. Musculoskeletal ultrasound examination indicated PIN entrapment at the inlet of the Frohse arch and the outlet of the supinator muscle. Therefore, PIN entrapment syndrome was diagnosed. After treatment with ultrasound-guided nerve hydrodissection around the entrapment point, the dorsiflexion weakness of the right hand was significantly improved compared with before treatment.

CONCLUSION

Ultrasound-guided hydrodissection is efficacious for PIN entrapment syndrome, with high clinical value and great application prospects.

Ultrasound-guided nerve hydrodissection of cervical nerve roots for cervical radicular pain in patients with mild and moderate to severe stenosis: a retrospective cohort study

Because fascial entrapment neuropathy can occur in multiple locations, ultrasound-guided nerve hydrodissection has become a key component of the treatment of cervical radicular pain. In this paper, we propose a combination of injectates used for nerve hydrodissection of the cervical nerve roots and compare the clinical outcomes of this treatment among patients with different severities of stenosis. This is a retrospective cohort study designed to compare outcomes between patients with mild stenosis and moderate to severe stenosis. Forty-four patients with mild cervical stenosis and 30 patients with moderate to severe cervical stenosis were consecutively enrolled into two groups. A 10-mL mixture in a single level consisting of 5% in Dextrose, 0.2% lidocaine (Xylocaine), and 4 mg betamethasone (Rinderon) was used for nerve roots hydrodissection. The two groups were compared with regard to their numeric rating scales (NRS) of pain, proportion of patients who exhibited a favorable outcome (a reduction of pain ≥ 50%), duration of patient exhibited a favorable outcome, and occurrence of serious complications and minor side effects. The follow-up period ranged from 3 to 20 months. The NRS of both groups improved significantly by 1 week, 1 month, 3 months, and final follow-up after the initial injection. Differences in the groups' NRS, proportion of patients who exhibited a favorable outcome, duration of patient exhibited a favorable outcome, and occurrence of serious complications and minor side effects were nonsignificant. There were 4 patients (5.4%) experienced dizziness in that resolved without further treatment. Ultrasound-guided nerve hydrodissection of cervical nerve roots is a safe procedure that reduces pain associated with cervical radicular pain, even in patients with moderate to severe stenosis.

Ultrasound-Guided Pulsed Radiofrequency Treatment for Superficial Peroneal Nerve Entrapment in a Professional Handball Player

Peripheral nerve injury in athletes is rare but deleterious to their performance, entrapment being one of the most frequent causes. Isolated injury to the superficial peroneal nerve (SPN) is rare and often underdiagnosed. The authors reported a clinical case of a 34-year-old handball athlete who presented with neuropathic pain in the inferolateral third of the leg and dorsum of the foot, with three months of evolution, after an ankle sprain, refractory to conservative treatment. After clinical assessment and ultrasound investigation, it was considered that the pain source was likely to be an SPN entrapment. Thus, a diagnostic ultrasound-guided nerve block with 2ml of 2% lidocaine and 3ml of 0.2% ropivacaine was performed, followed by nerve hydrodissection, with a major improvement in the patient's symptoms and functionality for three weeks. Thereafter, a long-lasting alternative was made - pulsed radiofrequency (pRF). There were no complications after the procedure. As a form of neuromodulation, pRF offered pain resolution without tissue damage or painful sequela, after 3, 6, 12, and 24 months of follow-up and complete participation in sports activity, avoiding surgical treatment. With this clinical case, the authors intend to demonstrate the effectiveness of pRF in the resolution of peripheral neuropathy due to entrapment, avoiding more invasive treatment options and, in the case of an athlete, allowing an early return to play. They also intend to corroborate the advantage of using ultrasound in the diagnosis and guide of minimally invasive procedures.

Ultrasound Imaging and Guidance for Distal Peripheral Nerve Pathologies at the Wrist/Hand

Ultrasound has emerged as a highly valuable tool in imaging peripheral nerve lesions in the wrist region, particularly for common pathologies such as carpal tunnel and Guyon's canal syndromes. Extensive research has demonstrated nerve swelling proximal to the entrapment site, an unclear border, and flattening as features of nerve entrapments. However, there is a dearth of information regarding small or terminal nerves in the wrist and hand. This article aims to bridge this knowledge gap by providing a comprehensive overview concerning scanning techniques, pathology, and guided-injection methods for those nerve entrapments. The median nerve (main trunk, palmar cutaneous branch, and recurrent motor branch), ulnar nerve (main trunk, superficial branch, deep branch, palmar ulnar cutaneous branch, and dorsal ulnar cutaneous branch), superficial radial nerve, posterior interosseous nerve, palmar common/proper digital nerves, and dorsal common/proper digital nerves are elaborated in this review. A series of ultrasound images are used to illustrate these techniques in detail. Finally, sonographic findings complement electrodiagnostic studies, providing better insight into understanding the whole clinical scenario, while ultrasound-guided interventions are safe and effective for treating relevant nerve pathologies.

Ultrasound-Guided Interventions for Carpal Tunnel Syndrome: A Systematic Review and Meta-Analyses

Carpal tunnel syndrome (CTS) is the most common peripheral entrapment, and recently, ultrasound-guided perineural injection (UPIT) and percutaneous flexor retinaculum release (UPCTR) have been utilized to treat CTS. However, no systematic review or meta-analysis has included both intervention types of ultrasound-guided interventions for CTS. Therefore, we performed this review using four databases (i.e., PubMed, EMBASE, Scopus, and Cochrane) to evaluate the quality of evidence, effectiveness, and safety of the published studies on ultrasound-guided interventions in CTS. Among sixty studies selected for systemic review, 20 randomized treatment comparison or controlled studies were included in six meta-analyses. Steroid UPIT with ultrasound guidance outperformed that with landmark guidance. UPIT with higher-dose steroids outperformed that with lower-dose steroids. UPIT with 5% dextrose in water (D5W) outperformed control injection and hydrodissection with high-volume D5W was superior to that with low-volume D5W. UPIT with platelet-rich plasma outperformed various control treatments. UPCTR outperformed open surgery in terms of symptom improvement but not functional improvement. No serious adverse events were reported in the studies reviewed. The findings suggest that both UPIT and UPCTR may provide clinically important benefits and appear safe. Further treatment comparison studies are required to determine comparative therapeutic efficacy.

Application of deep learning algorithms in automatic sonographic localization and segmentation of the median nerve: A systematic review and meta-analysis

OBJECTIVE

High-resolution ultrasound is an emerging tool for diagnosing carpal tunnel syndrome caused by the compression of the median nerve at the wrist. This systematic review and meta-analysis aimed to explore and summarize the performance of deep learning algorithms in the automatic sonographic assessment of the median nerve at the carpal tunnel level.

METHODS

PubMed, Medline, Embase, and Web of Science were searched from the earliest records to May 2022 for studies investigating the utility of deep neural networks in the evaluation of the median nerve in carpal tunnel syndrome. The quality of the included studies was evaluated using the Quality Assessment Tool for Diagnostic Accuracy Studies. The outcome variables included precision, recall, accuracy, F-score, and Dice coefficient.

RESULTS

In total, seven articles were included, comprising 373 participants. The deep learning and related algorithms comprised U-Net, phase-based probabilistic active contour, MaskTrack, ConvLSTM, DeepNerve, DeepSL, ResNet, Feature Pyramid Network, DeepLab, Mask R-CNN, region proposal network, and ROI Align. The pooled values of precision and recall were 0.917 (95 % confidence interval [CI], 0.873-0.961) and 0.940 (95 % CI, 0.892-0.988), respectively. The pooled accuracy and Dice coefficient were 0.924 (95 % CI, 0.840-1.008) and 0.898 (95 % CI, 0.872-0.923), respectively, whereas the summarized F-score was 0.904 (95 % CI, 0.871-0.937).

CONCLUSION

The deep learning algorithm enables automated localization and segmentation of the median nerve at the carpal tunnel level in ultrasound imaging with acceptable accuracy and precision. Future research is expected to validate the performance of deep learning algorithms in detecting and segmenting the median nerve along its entire length as well as across datasets obtained from various ultrasound manufacturers.

Ultrasound Imaging and Guidance for Cervical Myofascial Pain: A Narrative Review

Cervical myofascial pain is a very common clinical condition in the daily practice of musculoskeletal physicians. Physical examination is currently the cornerstone for evaluating the cervical muscles and identifying the eventual presence of myofascial trigger points. Herein, the role of ultrasound assessment in precisely localizing them is progressively mounting in the pertinent literature. Moreover, using ultrasound, not only the muscle tissue but also the fascial and neural elements can be accurately located/evaluated. Indeed, several potential pain generators, in addition to paraspinal muscles, can be involved in the clinical scenario of cervical myofascial pain syndrome. In this article, the authors extensively reviewed the sonographic approach for cervical myofascial pain in order to better diagnose or guide different procedures that can be performed in the clinical practice of musculoskeletal physicians.

Dynamic ultrasound for evaluating the adequacy of median nerve decompression following minimally invasive carpal tunnel release: technical innovation and case study

Background

Minimally invasive carpal tunnel release has recently emerged as the primary surgical approach for recalcitrant carpal tunnel syndrome. A major concern related to surgical failure with this technique is the incomplete release of the flexor retinaculum.

Case presentation

We developed a technique using dynamic ultrasound for evaluating the adequacy of median nerve decompression following minimally invasive carpal tunnel release. This novel imaging method was applied to two patients who showed significant symptom relief after the intervention. This case study also provides details of the dynamic ultrasound protocol and highlights the advantages of this technique.

Conclusion

Dynamic ultrasound imaging can be used to confirm the completeness of carpal tunnel decompression. A large-scale prospective trial should be conducted to validate whether additional dynamic ultrasound examination can improve the outcome of minimally invasive carpal tunnel release.

Serratus anterior plane block with ultrasound-guided hydrodissection for lateral thoracic pain caused by long thoracic nerve neuropathy - A case report

BACKGROUND

Long thoracic nerve (LTN) neuropathy occasionally occurs in young people who engage in various sports. It may have a traumatic or non-traumatic etiology. The landmark manifestation of LTN neuropathy is scapular winging; however, it can also occur without scapular winging and specific magnetic resonance imaging findings.

CASE

An 18-year-old male complained of right-sided lateral chest pain for 7 months. He was treated with medication, trigger point injection, and physical therapy but showed no improvement. Electromyelogram findings suggested LTN neuropathy in the right lateral chest. We performed a serratus anterior (SA) plane block with ultrasound (US)-guided hydrodissection and achieved pain relief.

CONCLUSIONS

We report the successful treatment of LTN neuropathy with an SA plane block and US-guided hydrodissection.

The Effectiveness of Hydrodissection with 5% Dextrose for Persistent and Recurrent Carpal Tunnel Syndrome: A Retrospective Study

Patients with failure of primary surgery for carpal tunnel syndrome (CTS) present a frustrating clinical problem because there are no relevant treatment guidelines, and the effect of current conservative management or revision surgery is unsatisfactory. Hydrodissection with 5% dextrose is emerging as an effective treatment for primary CTS and may be an effective alternative treatment method for persistent or recurrent post-surgical CTS. We retrospectively investigated the long-term effectiveness of hydrodissection with 5% dextrose for persistent or recurrent CTS. Thirty-six of forty consecutively-treated patients with either persistent or recurrent symptoms of CTS after surgery, who were treated with ultrasound-guided hydrodissection of the median nerve using 10 mL of 5% dextrose, were available to provide outcome data by a structured phone interview at least six months after treatment completion. Symptom relief ≥ 50% represented an effective outcome, while symptom relief < 50% was rated as a poor outcome. Nearly 2/3 (61.1%) of patients reported an effective outcome after a mean of 3.1 injections, with a post-injection follow-up mean of 33 (6−67) months. A non-significant trend toward a more frequently-effective outcome was observed in those with recurrent versus persistent symptoms following CTS (76.9% vs. 52.2%, p = 0.165). However, a significantly higher percentage of those with recurrent symptoms reported an excellent outcome, defined as a greater than 70% improvement (8/13 [61.6%] vs. 3/23 [13%], p = 0.006). The percentage of patients achieving an effective outcome was not significantly different between <2, 2−4, and >4 years of post-treatment follow-up (36.4% vs. 77.8% vs. 57.1%; p = 0.077). Hydrodissection with 5% dextrose may result in a clinically important and durable benefit in those experiencing persistent or recurrent CTS after surgery.

Mechanism of Glucose Water as a Neural Injection: A Perspective on Neuroinflammation

The entrapment of peripheral nerves is associated with chronic neuroinflammation and neuropathic pain, and perineural injection therapy with glucose is emerging as an effective treatment for peripheral entrapment neuropathy. However, the mechanism underlying the pharmacological effect of glucose on nerves remains unclear. One of the hypothesized mechanisms is that glucose reduces neurogenic inflammation. Therefore, we investigated the effects of high glucose concentrations on cytokine-induced neuroinflammation in vitro. Human SH-SY5Y neuronal cells were challenged with 10 ng/mL TNF-α for 16 h and subsequently treated with different glucose concentrations (0–25 mM) for 24 h. Cell viability was evaluated using the diphenyltetrazolium bromide assay, and proinflammatory cytokine levels were assessed using ELISA and quantitative PCR. In addition, mRNA levels of NF-κB and cyclooxygenase-2 were analyzed using quantitative PCR. Exposure to 10 ng/mL TNF-α resulted in decreased viability of SH-SY5Y cells and significant upregulation of IL-6, IL-1β, NF-κB, and cyclooxygenase-2. Subsequent exposure to high glucose levels (25 mM) markedly reduced the upregulation of IL-6, IL-1β, cyclooxygenase-2, and NF-κB, and restored the functional metabolism of SH-SY5Y cells, compared with that of the normal glucose control. Our findings suggest that high glucose concentrations can mitigate TNF-α-induced NF-κB activation, upregulation of proinflammatory cytokines, and metabolic dysfunction.

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.

Novel Motor-Sparing Ultrasound-Guided Neural Injection in Severe Carpal Tunnel Syndrome: A Comparison of Four Injectates

Nerve hydrodissection uses fluid injection under pressure to selectively separate nerves from areas of suspected entrapment; this procedure is increasingly viewed as potentially useful in treating carpal tunnel syndrome (CTS). The usage of normal saline (NS), 5% dextrose water (D5W), platelet-rich plasma (PRP), and hyaluronic acid (HA) as primary injectates for hydrodissection without an anesthetic can limit anesthetic-related toxicity and preserve the motor functions of the median nerve. Here, we describe a novel motor-sparing neural injection and compare the effect of these four injectates for severe CTS. We retrospectively reviewed the outcomes of 61 severe CTS cases after a single neural injection with NS, D5W, PRP, or HA. Outcomes were evaluated on the 1st and 6th months postinjection, including the Boston Carpal Tunnel Questionnaire (BCTQ) scores and the nerve cross-sectional area (CSA). The results revealed that PRP, D5W, and HA were more efficient than NS at all measured time points ( $p<0.05$ ), except for CSA at the 1st month between the NS and D5W groups. Single-injections of PRP and D5W seemed more effective than that of HA within 6 months postinjection for symptom and functional improvement (6th-month BCTQ-symptom, D5W vs. HA, $p=0.047$ ; 1st-month BCTQ-symptom, PRP vs. HA, $p=0.018$ ; 1st- and 6th-month BCTQ-function, D5W vs. HA, $p=0.002$ and 0.016, respectively; 1st-month BCTQ-function, PRP vs. HA, $p<0.001$ ). For reducing CSA, PRP and HA seemed more effective than D5W ( $\text{HA}>\text{PRP}>\text{D}5\text{W}$ on the 1st month and HA vs. D5W, $p=0.001$ ; $\text{PRP}>\text{HA}>\text{D}5\text{W}$ on the 6th month and PRP vs. D5W, $p=0.012$ ).

A Review of Upper Extremity Peripheral Nerve Injuries in Throwing Athletes

Peripheral nerve injuries in the upper extremities may be common in throwing athletes as the throwing motion places extreme stress on the dominant arm. The combination of extreme stress along with repetitive microtrauma from throwing uniquely places the throwing athlete at elevated risk of upper extremity peripheral nerve injury. However, because symptoms can be non-specific and frequent co-exist with pathology in the upper extremity, the diagnosis of peripheral nerve injury is often delayed. Diagnosis of peripheral nerve injuries may require a combination of history and physical exam, diagnostic imaging, electrodiagnostic testing, and diagnostic ultrasound guided injections. The primary management should include physical therapy focusing on throwing mechanics and kinetic chain evaluation. However, some athletes require surgical intervention if symptoms do not improve with conservative management. The purpose of this focused narrative review is to highlight upper extremity peripheral neuropathies reported in throwing athletes and to provide an overview of the appropriate clinical diagnosis and management of the throwing athlete with a peripheral nerve injury. This article is protected by copyright. All rights reserved.

Efficacy of 5% Dextrose Water Injection for Peripheral Entrapment Neuropathy: A Narrative Review

Current non-surgical treatment for peripheral entrapment neuropathy is considered insignificant and unsustainable; thus, it is essential to find an alternative novel treatment. The technique of perineural injection therapy using 5% dextrose water has been progressively used to treat many peripheral entrapment neuropathies and has been proven to have outstanding effects in a few high-quality studies. Currently, the twentieth edition of Harrison’s Principles of Internal Medicine textbook recommends this novel injection therapy as an alternative local treatment for carpal tunnel syndrome (CTS). Hence, this novel approach has become the mainstream method for treating CTS, and other studies have revealed its clinical benefit for other peripheral entrapment neuropathies. In this narrative review, we aimed to provide an insight into this treatment method and summarize the current studies on cases of peripheral entrapment neuropathy treated by this method.

Dorsal scapular nerve entrapment neuropathy managed by ultrasound-guided hydrodissection - a case report

There are myriad causes for upper thoracic and interscapular pain which include pathologies involving the thoracic spine, costovertebral joints, facet joints and muscles (rhomboids and levator scapulae). Dorsal scapular nerve entrapment and the resulting neuropathy is a rare case of upper thoracic and medial scapular pain. The symptoms of dorsal scapular nerve entrapment neuropathy can be similar to other pathologies mentioned above. We report a rare case of dorsal scapular nerve entrapment managed successfully by ultrasound-guided hydrodissection, and describe the technique for the same. Awareness of this rare entity is advised while evaluating upper thoracic and interscapular pain.

The efficacy of hyaluronic acid for carpal tunnel syndrome: a randomized double-blind clinical trial

OBJECTIVES

To investigate the effect of hyaluronic acid (HA) in patients diagnosed with mild or moderate carpal tunnel syndrome (CTS).

DESIGN

A prospective randomized, double-blinded control study with 6 months of follow-up.

SETTING

Rehabilitation outpatient clinic of one single medical center.

SUBJECTS

Thirty-five participants with mild or moderate CTS.

METHODS

Participants were enrolled and randomly assigned to HA or control groups. The HA group received one ultrasound-guided perineural injection of 2.5 ml HA while the control group received 2.5 ml normal saline injection through in-plane, long-axis approach to separate the median nerve from the flexor retinaculum via nerve hydrodissection. Boston Carpal Tunnel Syndrome Questionnaire (BCTQ) scores were the primary outcome, while secondary outcomes included the numeric rating scale (NRS), electrophysiological domains, and the cross-sectional area of the median nerve. The assessment was conducted prior to injection and during the second week and 1-, 3-, and 6-months post-injection.

RESULTS

Thirty-two patients (17 wrists in HA group and 15 wrists in control group) completed the study. Compared with the control group, the HA group did not show significantly superior outcomes, except in BCTQ and NRS at the second week post-injection (all p < 0.0125).

CONCLUSIONS

A single ultrasound guided perineural HA injection may have short-term therapeutic efficacy for mild or moderate CTS; however, the 2-weeks superior efficacy was not beneficial for chronic neuropathy. Further studies with larger sample sizes are required to verify its therapeutic efficacy.

The Effectiveness and Safety of Commonly Used Injectates for Ultrasound-Guided Hydrodissection Treatment of Peripheral Nerve Entrapment Syndromes: A Systematic Review

Background: Peripheral nerve entrapment syndromes commonly result in pain, discomfort, and ensuing sensory and motor impairment. Many conservative measures have been proposed as treatment, local injection being one of those measures. Now with high-resolution ultrasound, anatomical details can be visualized allowing diagnosis and more accurate injection treatment. Ultrasound-guided injection technique using a range of injectates to mechanically release and decompress the entrapped nerves has therefore developed called hydrodissection or perineural injection therapy. Several different injectates from normal saline, local anesthetics, corticosteroids, 5% dextrose in water (D5W), and platelet-rich plasma (PRP) are available and present clinical challenges when selecting agents regarding effectiveness and safety.

Aims: To systematically search and summarize the clinical evidence and mechanism of different commonly used injectates for ultrasound-guided hydrodissection entrapment neuropathy treatment.

Methods: Four databases, including PubMed, EMBASE, Scopus, and Cochrane were systematically searched from the inception of the database up to August 22, 2020. Studies evaluating the effectiveness and safety of different commonly used injectates for ultrasound-guided hydrodissection entrapment neuropathy treatment were included. Injectate efficacy presents clinical effects on pain intensity, clinical symptoms/function, and physical performance, electrodiagnostic findings, and nerve cross-sectional areas. Safety outcomes and mechanism of action of each injectate were also described.

Results: From ten ultrasound-guided hydrodissection studies, nine studies were conducted in carpal tunnel syndrome and one study was performed in ulnar neuropathy at the elbow. All studies compared different interventions with different comparisons. Injectates included normal saline, D5W, corticosteroids, local anesthetics, hyaluronidase, and PRP. Five studies investigated PRP or PRP plus splinting comparisons. Both D5W and PRP showed a consistently favorable outcome than those in the control group or corticosteroids. The improved outcomes were also observed in comparison groups using injections with normal saline, local anesthetics, or corticosteroids, or splinting. No serious adverse events were reported. Local steroid injection side effects were reported in only one study.

Conclusion: Ultrasound-guided hydrodissection is a safe and effective treatment for peripheral nerve entrapment. Injectate selection should be considered based on the injectate mechanism, effectiveness, and safety profile.

Quantitative Ultrasonographic Analysis of Changes of the Suprascapular Nerve in the Aging Population With Shoulder Pain

Background

Older people are vulnerable to painful shoulder syndromes, the majority of which are derived from degenerative rotator cuff pathologies. The suprascapular nerve (SSN) is closely related to the rotator cuff complex, and its role in shoulder pain has recently been highlighted. This study aimed to explore the differences in SSN among older people with and without shoulder pain, and to investigate the potential factors influencing the nerve size using ultrasound (US) imaging.

Methods

Participants aged ≥60 years were enrolled in the study. A systematic and bilateral US examination of the rotator cuff tendons was performed. The SSN was examined from its origin in the brachial plexus to the spinoglenoid notch of the infraspinatus fossa. The association between the nerve’s cross-sectional area (CSA) and rotator cuff lesions was analyzed using the generalized estimation equation.

Results

Among the 94 participants, 45 (with bilaterally asymptomatic shoulders) were classified into the control group, whereas 49 (with at least one-sided shoulder pain) were classified into the group with shoulder pain. The average CSAs of the SSN at the level of the brachial plexus, supraspinatus fossa, and infraspinatus fossa were comparable between the patients in the control group and those with shoulder pain. There was a higher prevalence of rotator cuff lesions and enlarged distal SSNs in the painful shoulders than in the asymptomatic shoulders of patients with unilateral involvement. A full-thickness tear of the supraspinatus tendon was associated with swelling of the SSN in the supraspinatus fossa (β coefficient = 4.068 mm², p < 0.001).

Conclusion

In the older population, full-thickness tears of the supraspinatus tendon are independently associated with enlargement of the distal SSN. In cases with large rotator cuff tendon tears with poor response to conservative treatments, possible SSN entrapment should be considered and managed accordingly.

Prognostic factors in carpal tunnel syndrome treated with 5% dextrose perineural injection: A retrospective study

Background: Perineural injection therapy with 5% dextrose water (D5W) is a potential and innovative treatment with long-term efficacy for carpal tunnel syndrome (CTS). However, the prognostic factors of this management are lacking; hence, the aim of this retrospective study was to identify the prognostic factors of D5W perineural injection therapy for mild-to-moderate CTS. Methods: A total of 52 patients (52 wrists) diagnosed with mild-to-moderate CTS and treated with a single ultrasound-guided 5cc D5W perineural injection were retrospectively reviewed. Patient-reported injection outcomes (visual analog scale, VAS) at 6 months post-injection were categorized into two groups; (1) Good outcome, when symptom relief ≥50% compared to pre-injection and (2) Poor outcome, when symptom relief < 50% compared to pre-injection. Significant variables between groups were entered into a binary logistic regression with forward stepwise regression to determine the prognostic factors for these outcomes. Results: The treatment outcome was significantly related to body height and sensory nerve conduction velocity (SNCV) (159.1 ± 1.0 vs. 155.0 ± 1.8, p=0.04; 33.6 ± 0.8 vs. 28.3 ± 1.2, p=0.001, good vs. poor outcomes). However, only SNCV remained significantly correlated with the outcomes after conducting stepwise logistic regression (ORs: 1.201; 95% CI 1.05-1.38; p=0.01). Conclusions: SNCV was found to be a significant prognostic factor of treatment outcome for patients with mild-to-moderate CTS 6 months after a D5W perineural injection.

Ultrasound-Guided Hydrodissection for Baxter's Neuropathy Secondary to Plantar Fasciitis: A Case Report

Plantar heel pain is a common pain condition encountered in clinical practice. The common etiologies include plantar fasciitis, calcaneal spur, calcaneus stress fracture, systemic causes, and trauma. Neurogenic causes, including entrapment at the tarsal tunnel or Baxter's nerve entrapment, can contribute to the heel pain and should not be overlooked. In this case report, we describe a patient with severe heel pain, presenting with overlapping features of plantar fasciitis and neuropathic pain. Magnetic resonance imaging suggested Baxter's nerve entrapment, and a subsequent ultrasound-guided hydrodissection of Baxter's nerve provided long-lasting pain relief.