Accuracy of Ultrasonography for the Diagnosis of Carpal Tunnel Syndrome: A Systematic Review and Meta-Analysis

Efficacy of dry needling with the fascial winding technique in reducing the percentage of surgery in carpal tunnel syndrome: A randomized clinical trial

INTRODUCTION

Numerous techniques for the treatment of carpal tunnel syndrome (CTS) have been described. The present study aims to determine the proportion of wrists with CTS in which the application of DN avoids surgery.

METHODS

An assessor-blind randomized clinical trial clinical trial was performed. Eighty-six wrists with diagnosis of mild or moderate CTS and indication for surgery were recruited from a hospital traumatology service. The intervention group was treated with DN, with a frequency of one session/week over six weeks, while the control group did not follow any specific treatment, remaining on the waiting list for the surgery. The main variable was the recommendation for surgery. Other secondary variables included changes in electromyography and ultrasound; intensity of pain; Boston Carpal Tunnel Syndrome Questionnaire (BCTQ); hand dynamometries; and possible adverse effects.

RESULTS

The wrists treated by DN had a reduced risk of needing surgery at 12 weeks by 62% compared to the control group (RR = 0.38, 95% CI[0.2-0.72]), with this value being significant (p-value = 0.003). This group also obtained a significant improvement in the intensity of pain (p-value = 0.006), and in the BCTQ-severity of syntoms scale and BCTQ-functional situation scale (p-value = 0.039 and p-value = 0.019 respectively). Statistical significance was not reached in the dynamometries performed, nor in the results of the electromyography and ultrasound studies. Adverse effects were infrequent or unimportant.

CONCLUSIONS

Application of DN to wrists with mild or moderate CTS reduces the need for surgery, and improves the clinical symptoms and functionality of the hand.

Diagnostic challenges of carpal tunnel syndrome in patients with congenital thenar hypoplasia: a comprehensive review

Carpal Tunnel Syndrome (CTS) is the most common entrapment neuropathy, frequently presenting with pain, numbness, and muscle weakness due to median nerve compression. However, diagnosing CTS becomes particularly challenging in patients with Congenital Thenar Hypoplasia (CTH), a rare congenital anomaly characterized by underdeveloped thenar muscles. The overlapping symptoms of CTH and CTS, such as thumb weakness, impaired hand function, and thenar muscle atrophy, can obscure the identification of median nerve compression. This review highlights the diagnostic complexities arising from this overlap and evaluates existing clinical, imaging, and electrophysiological assessment methods. While traditional diagnostic tests, including Phalen's and Tinel's signs, exhibit limited sensitivity in CTH patients, advanced imaging modalities like ultrasonography (US), magnetic resonance imaging (MRI), and diffusion tensor imaging (DTI) provide valuable insights into structural abnormalities. Additionally, emerging technologies such as artificial intelligence (AI) enhance diagnostic precision by automating imaging analysis and identifying subtle nerve alterations. Combining clinical history, functional assessments, and advanced imaging, an interdisciplinary approach is critical to differentiate between CTH-related anomalies and CTS accurately. This comprehensive review underscores the need for tailored diagnostic protocols to improve early detection, personalised management, and outcomes for this unique patient population.

Diagnostic Value of Measurements of Median Nerve Diameter at the Site of the Maximal Stenosis in Carpal Tunnel Syndrome

Introduction

Ultrasonography is increasingly used to diagnose the carpal tunnel syndrome (CTS). Most frequently, the enlargement of the nerve cross-sectional area (CSA) at the tunnel inlet serves to confirm the diagnosis. Recent research has shown that the nerve diameter is decreased within the tunnel, when measured at the level of pisiforme or capitatum. The stenosis index (SI), which uses the ratio of the diameter of median nerve at the tunnel inlet to the diameter within the tunnel (SI diameter), was proposed as the diagnostic marker of CTS. In this study, we compared the diameter of the median nerve measured at the site of maximal stenosis (DMS) between patients with CTS and controls. Additionally, we investigated the diagnostic utility of the modified SI, which uses the ratio of CSA at the inlet to the diameter within the tunnel (SI CSA).

Methods

Forty-eight patients (72 hands) with CTS and 18 asymptomatic controls (28 hands) underwent electrodiagnostic testing and ultrasonography.

Results

CSA at the inlet was larger in patients, whereas DMS showed only trend towards being smaller in CTS. CTS was also associated with more distal localization of maximal stenosis. Both SI diameter and SI CSA were higher in patients, however the discriminative effect of SI CSA was stronger. SI diameter, SI CSA, CSA at the inlet and DMS correlated with the electrodiagnostic severity grade of CTS. The post-hoc analysis revealed that patients with moderate and severe electrodiagnostic grade of CTS have smaller DMS, whereas patients with mild CTS did not differ from controls.

Conclusion

DMS seems to have only limited diagnostic potential in mild CTS, but it may be a marker of more advanced cases. CTS may be associated with the distal shift of DMS. SI CSA may have significant diagnostic potential in CTS.

Diagnostic Dilemmas in Carpal Tunnel Syndrome and Cervical Spine Disorders: A Comprehensive Review

Carpal tunnel syndrome (CTS) and cervical spondylosis (CS) are both common diseases, yet differentiation between the two is sometimes necessary. However, there are few evidence-based reviews on the differentiation of these conditions. This review examined the literature on the diagnosis of CTS and CS, focusing on how to distinguish between them. The analysis is divided into four categories: clinical symptoms, physical examination, diagnostic imaging, and electrodiagnosis. A total of 281 studies are reviewed, revealing a major issue: the inclusion criteria for defining each disease varies widely across studies. Understanding this limitation, the conclusion drawn is that no single clinical symptom, test, or imaging evaluation can be deemed uniquely reliable for diagnosing CTS or CS. Therefore, it is essential to apply the most up-to-date knowledge, conduct thorough examinations, and perform necessary tests for each patient to achieve a confident and accurate diagnosis.

Ultrasound Assessment of the Ulnar Nerve Around the Elbow and Diagnosis of Cubital Tunnel Syndrome, Clinical Outcomes

BACKGROUND

There is increased interest in ultrasound (US) for the diagnosis of cubital tunnel syndrome (CuTS). We hypothesize that ulnar nerve cross-sectional area (CSA) correlates with disease severity and electrodiagnostic studies (EDX).

METHODS

ARetrospective review was performed at a tertiary medical center. One hundred seventeen patients (166 ulnar nerves) were evaluated. Maximum CSA at 3 points around the elbow (proximal, groove, and distal) and EDX results (American Board of Electrodiagnostic Medicine-certified physiatrist's interpretations) were collected.

RESULTS

US was positive (CSA > 0.1 cm2) in 95/117 cases (81.20%) versus 84/117 (71.79%) positive for EDX. CuTS patients treated surgically had significantly greater (0.13 cm2, standard deviation [SD] 0.038) preoperative CSA than non-operative patients (0.10 cm2, SD 0.033) (p = .003). CSA increased as EDX increased in severity; mild (0.116 cm2, SD 0.031), moderate (0.121 cm2, SD 0.035), and severe (0.163 cm2, SD 0.047) with a significant difference between the mild and severe groups (P = .001) and between the moderate and severe groups (p = .01). Significant differences were seen between patients with positive US and EDX studies compared to those with negative US and EDX in the average physical function scores (57.26, SD 8.57 versus 43.18, SD 7.70; p < .001); average sleep scores (50.14, SD 9.53 versus 56.62, SD 7.31; p = .02); average physical function scores (43.04, SD 8.68 versus 57.08, SD 6.34; p < .001) and average depression scores (49.10, SD 10.88 versus 45.043, SD 7.06; p = .02).

CONCLUSIONS

US is a reliable tool for diagnosis and surgical decision-making for CuTS.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic/III.

Association between electrodiagnosis and neuromuscular ultrasound in the diagnosis and assessment of severity of carpal tunnel syndrome

BACKGROUND

Neuromuscular ultrasound plays an increasing role in diagnosing carpal tunnel syndrome (CTS). There are limited data supporting the correlation between the electrodiagnostic studies and ultrasound measurements in CTS.

OBJECTIVE

To assess the association between different electrodiagnostic severities and ultrasound measurements of the median nerve in CTS.

DESIGN

A retrospective cohort study.

SETTING

An academic tertiary care center.

PATIENTS

Patients 18 years or older evaluated with upper limb electrodiagnostic studies and neuromuscular ultrasound.

MAIN OUTCOME MEASUREMENT

Ultrasound measurements of the median nerve cross-sectional area (CSA) at the wrist and the calculated wrist-to-forearm ratio (WFR) were compared with the electrodiagnostic severity (normal, mild, moderate, and severe). Mean analysis and analysis of variance test (α = 0.05) were performed to assess the association.

RESULTS

A total of 1359 limbs were identified. There was a statistically significant association between electrodiagnostic severity of CTS and median nerve CSA at the wrist (p < .001), as well as the WFR (p < .001). The mean median nerve CSA at the wrist and WFR were 7.01 ± 2.06 mm2 (95% CI: 6.80-7.20) and 1.24 ± 0.36 (95% CI: 1.16-1.24) in electrodiagnostically normal median nerves, 10.47 ± 2.82 mm2 (95% CI: 10.25-10.75) and 2.06 ± 0.67 (95% CI: 2.04-2.16) in electrodiagnostically mild CTS, 12.95 ± 4.74 mm2 (95% CI: 12.41-13.59) and 2.49 ± 1.04 (95% CI: 2.37, 2.63) in electrodiagnostically moderate CTS, and 14.69 ± 5.38 mm2 (95% CI: 13.95-15.44) and 2.71 ± 1.02 (95% CI: 2.56-2.84) in electrodiagnostically severe CTS, respectively.

CONCLUSION

This study suggests a direct association between electrodiagnostic severity and ultrasound measurements of the median nerve in patients with suspected CTS.

Ultrasound Diagnosis of Upper Extremity Peripheral Entrapment Neuropathies: A Narrative Review

» Diagnostic ultrasound evaluation has become an important adjunct to electrodiagnostic studies in the diagnosis of upper extremity entrapment neuropathy. » For the common median and ulnar entrapment neuropathies, published normative values for nerve cross-sectional area at the wrist and elbow have demonstrated a high degree of diagnostic validity of diagnostic ultrasound. » Expert consensus on best practice for the clinical use of these reference is lacking and should be a logical next step in the deployment of ultrasound for upper extremity neuropathy evaluation.

Advances in Imaging of Compressive Neuropathies

Ultrasound and magnetic resonance neurography are useful modalities to aid in the assessment of compressive neuropathies, although they are still limited in their resolution of nerve microstructure and their capacity to monitor postoperative nerve recovery. Optical coherence tomography, a preclinical imaging modality, is promising in its ability to better identify structural and potential physiologic changes to peripheral nerves, but requires additional testing and research prior to widespread clinical implementation. Further advances in nerve imaging may elucidate the ability to visualize the zone of nerve injury intraoperatively, monitor the progression of nerve regeneration, and localize problems during nerve recovery.

Automated segmentation of the median nerve in patients with carpal tunnel syndrome

Machine learning and deep learning are novel methods which are revolutionizing medical imaging. In our study we trained an algorithm with a U-Net shaped network to recognize ultrasound images of the median nerve in the complete distal half of the forearm and to measure the cross-sectional area at the inlet of the carpal tunnel. Images of 25 patient hands with carpal tunnel syndrome (CTS) and 26 healthy controls were recorded on a video loop covering 15 cm of the distal forearm and 2355 images were manually segmented. We found an average Dice score of 0.76 between manual and automated segmentation of the median nerve in its complete course, while the measurement of the cross-sectional area at the carpal tunnel inlet resulted in a 10.9% difference between manually and automated measurements. We regard this technology as a suitable device for verifying the diagnosis of CTS.

Diagnostic meta-analysis of the efficacy of ultrasonography for diagnosing carpal tunnel syndrome: A comparison between Asian and non-Asian populations

BACKGROUND

Ultrasonography is used to diagnose carpal tunnel syndrome (CTS) according to various criteria. This diagnostic meta-analysis aimed to evaluate the efficacy of ultrasonography for diagnosing CTS, focusing on the cross-sectional area (CSA) of the median nerve (MN) at the inlet of the carpal tunnel and regional variations in diagnostic thresholds between Asian and non-Asian populations.

METHODS

A comprehensive literature search was conducted using PubMed, Embase, and the Cochrane Library. The risk of bias was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2). Patient demographic data, diagnostic "gold standards", CSA cutoff values, and diagnostic results were extracted. Meta-analysis was performed to determine the sensitivity, specificity, and optimal CSA cutoff values.

RESULTS

For the 25 included studies, a combined sensitivity of 88% and specificity of 84% for CSA measurements at the carpal tunnel inlet were obtained. The Asian group had a sensitivity of 84% and specificity of 86%, while the non-Asian group had a sensitivity of 91% and specificity of 82%. The mean CSA in the Asian group was significantly lower than that in the non-Asian group (12.93 mm2 and 14.77 mm2, respectively; p = 0.042). For the Asian group, the summary receiver operating characteristic curve had an area under the curve (AUC) of 0.92 with an optimal cutoff of 10.5 mm2; for the non-Asian group, an AUC of 0.94 was obtained with a cutoff of 11.5 mm2.

CONCLUSION

Ultrasonography is a reliable diagnostic method for CTS, with distinct optimal cutoff values observed between Asian and non-Asian populations. Therefore, population-specific diagnostic criteria for CTS are recommended.

Application of radiomics model based on ultrasound image features in the prediction of carpal tunnel syndrome severity

OBJECTIVE

The aim of our study is to develop and validate a radiomics model based on ultrasound image features for predicting carpal tunnel syndrome (CTS) severity.

METHODS

This retrospective study included 237 CTS hands (106 for mild symptom, 68 for moderate symptom and 63 for severe symptom). There were no statistically significant differences among the three groups in terms of age, gender, race, etc. The data set was randomly divided into a training set and a test set in a ratio of 7:3. Firstly, a senior musculoskeletal ultrasound expert measures the cross-sectional area of median nerve (MN) at the scaphoid-pisiform level. Subsequently, a recursive feature elimination (RFE) method was used to identify the most discriminative radiomic features of each MN at the entrance of the carpal tunnel. Eventually, a random forest model was employed to classify the selected features for prediction. To evaluate the performance of the model, the confusion matrix, receiver operating characteristic (ROC) curves, and F1 values were calculated and plotted correspondingly.

RESULTS

The prediction capability of the radiomics model was significantly better than that of ultrasound measurements when 10 robust features were selected. The training set performed perfect classification with 100% accuracy for all participants, while the testing set performed accurate classification of severity for 76.39% of participants with F1 values of 80.00, 63.40, and 84.80 for predicting mild, moderate, and severe CTS, respectively. Comparably, the F1 values for mild, moderate, and severe CTS predicted based on the MN cross-sectional area were 76.46, 57.78, and 64.00, respectively..

CONCLUSION

This radiomics model based on ultrasound images has certain value in distinguishing the severity of CTS, and was slightly superior to using only MN cross-sectional area for judgment. Although its diagnostic efficacy was still inferior to that of neuroelectrophysiology. However, this method was non-invasive and did not require additional costs, and could provide additional information for clinical physicians to develop diagnosis and treatment plans.

ACR Appropriateness Criteria® Chronic Hand and Wrist Pain: 2023 Update

Chronic hand and wrist pain is a common presenting complaint. The intricate anatomy results in a variety of pain generators-multiple bones, articular cartilage, intrinsic ligaments, triangular fibrocartilage complex, joint capsules and synovium, tendons and tendon sheaths, muscles, and nerves-in a compact space. The need for imaging and the choice of the appropriate imaging modality are best determined by the patient's presentation, physical examination, and the clinician's working differential diagnosis. Radiography is usually appropriate as the initial imaging study in the evaluation of chronic hand or wrist pain. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Ultrasound-An Easy Available and Useful Point-of-Care Adjunct for Clinical Decision-Making in Hand Infections: Review of the Literature and a Case Series

ABSTRACT

Initial findings of hand infections warrant a thorough treatment strategy depending on the progress of the infection. The decision for surgical treatment can be unclear. Searching to improve the quality of diagnostics, we reviewed the literature regarding the use of point-of-care ultrasound (PCUS) in hand infections and analyzed patients undergoing decision-making with PCUS. We searched PubMed, Scopus, Cochrane Register, and Google Scholar for the use of PCUS in therapy planning in infections of the hand. In addition, we screened our patients from July 1, 2020, to November 30, 2020, to validate the potential benefit of ultrasound examination in suspected hand infections. We evaluated initial clinical examinations versus blinded sonographic assessments in the context of correct decision to proceed with surgery or conservative treatment. Two thousand forty-eight studies within the topic were identified, but only 9 studies were found eligible to be included with a total of 88 patients. The studies illustrate that ultrasound can be performed on all patients, including children and pregnant women, and can be performed in a timely manner. In our retrospective analysis of 20 patients with suspected hand infection, the clinical and ultrasound assessment led to surgery in 13 cases. Of those 13 patients, 7 revealed intraoperative pus. By retrospective assessment of solely the ultrasound images, surgery would have been indicated in 9 cases, including all 7 cases with intraoperative pus. Clinical examination and ultrasound can help in detecting infections of the hand. Ultrasound examination, however, seems to yield a lower false-positive rate than clinical examination. Ultrasound could be a valuable addition to clinical examination.

In Vivo Effects of Joint Movement on Nerve Mechanical Properties Assessed with Shear-Wave Elastography: A Systematic Review and Meta-Analysis

Peripheral nerves are subjected to mechanical tension during limb movements and body postures. Nerve response to tensile stress can be assessed in vivo with shear-wave elastography (SWE). Greater tensile loads can lead to greater stiffness, which can be quantified using SWE. Therefore, this study aimed to conduct a systematic review and meta-analysis to perform an overview of the effect of joint movements on nerve mechanical properties in healthy nerves. The initial search (July 2023) yielded 501 records from six databases (PubMed, Embase, Scopus, Web of Science, Cochrane, and Science Direct). A total of 16 studies were included and assessed with a modified version of the Downs and Black checklist. Our results suggest an overall tendency for stiffness increase according to a pattern of neural tensioning. The main findings from the meta-analysis showed a significant increase in nerve stiffness for the median nerve with wrist extension (SMD [95%CI]: 3.16 [1.20, 5.12]), the ulnar nerve with elbow flexion (SMD [95%CI]: 2.91 [1.88, 3.95]), the sciatic nerve with ankle dorsiflexion (SMD [95%CI]: 1.13 [0.79, 1.47]), and the tibial nerve with both hip flexion (SMD [95%CI]: 2.14 [1.76, 2.51]) and ankle dorsiflexion (SMD [95%CI]: 1.52 [1.02, 2.02]). The effect of joint movement on nerve stiffness also depends on the nerve segment, the amount of movement of the joint mobilized, and the position of other joints comprised in the entirety of the nerve length. However, due to the limited number of studies, many aspects of nerve behavior together with the effect of using different ultrasound equipment or transducers for nerve stiffness evaluation still need to be fully investigated.

[Analysis of the echographic parameters described in the study of carpal tunnel syndrome: A systematic review]

Carpal tunnel syndrome (CTS) is the most common entrapment mononeuropathy; the diagnosis is established by electrodiagnostic tests with until 34% of false positives/negatives. We present the following systematic review which objective is to analyze the most recent literature related to the ultrasound parameters described to study CTS. We selected studies that evaluated ultrasound parameters in patients with clinical suspicion following the Cochrane manual's recommendations. We include systematic reviews, meta-analyses, case-control studies and diagnostic tests, evaluating retrospective studies and bibliographic reviews with proper methodological quality. Articles published between 2005 and 2019. We included eight articles (two systematic reviews/meta-analyses, two case-control studies, one diagnostic test study, two literature reviews, and one retrospective). The parameters analyzed were cross-sectional area, wrist-forearm index, entry-exit index, thinning range, palmar bowing of the flexor retinaculum, and vascularity/mobility. Current evidence allows us to affirm that ultrasound is useful in screening for CTS.

Acroparesthesias: An Overview

Acroparesthesia is a symptom characterized by a subjective sensation, such as numbness, tingling, prickling, and reduced sensation, affecting the extremities (fingers and toes). Despite its frequency, data regarding its diagnostic approach and management are scarce. The etiological diagnosis of acroparesthesia is sometimes challenging since it can be due to abnormality anywhere along the sensory pathway from the peripheral nervous system to the cerebral cortex. Acroparesthesia can reveal several diseases. It can be associated with rheumatic complaints such as arthritis or myalgia. Further cautions are required when paresthesia is acute (within days) in onset, rapidly progressive, severe, asymmetric, proximal, multifocal, or associated with predominant motor signs (limb weakness) or severe dysautonomia. Acroparesthesia may reveal Guillain-Barré syndrome or vasculitis, requiring rapid management. Acroparesthesia is a predominant symptom of polyneuropathy, typically distal and symmetric, often due to diabetes. However, it can occur in other diseases such as vitamin B12 deficiency, monoclonal gammopathy of undetermined significance, or Fabry's disease. Mononeuropathy, mainly carpal tunnel syndrome, remains the most common cause of acroparesthesia. Ultrasonography contributes to the diagnosis of nerve entrapment neuropathy by showing nerve enlargement, hypoechogenic nerve, and intraneural vascularity. Besides, it can reveal its cause, such as space-occupying lesions, anatomical nerve variations, or anomalous muscle. Ultrasonography is also helpful for entrapment neuropathy treatment, such as ultrasound-guided steroid injection or carpal tunnel release. The management of acroparesthesia depends on its causes. This article aimed to review and summarize current knowledge on acroparesthesia and its causes. We also propose an algorithm for the management of acroparesthesia.

Diagnosis of Ulnar Neuropathy at the Elbow Using Ultrasound - A Comparison to Electrophysiologic Studies

PURPOSE

Given the relatively high false negative rate of electrodiagnostic studies (EDX) in patients with clinically diagnosed ulnar neuropathy at the elbow (UNE), we sought to determine whether an alternative objective test could more effectively detect UNE. Additionally, we proposed to determine the relationship between the cross-sectional area (CSA) of the ulnar nerve on ultrasound (US), EDX, and clinical symptoms.

METHODS

This was a retrospective study of patients presenting with symptomatic UNE. The performance characteristics of EDX versus ultrasound were calculated using the clinical diagnosis of UNE as the reference standard. Standard EDX studies and US of the ulnar nerve were analyzed. Maximal CSA of the ulnar nerve and EDX severity were analyzed for patients with each combination of US-positive/negative and EDX-positive/negative findings.

RESULTS

Analysis was performed on 89 patients and 115 nerves with signs and symptoms of cubital tunnel syndrome. In total, 56 (49%) nerves were diagnosed as mild UNE, 32 (28%) nerves were diagnosed as moderate UNE, 17 (15%) nerves were diagnosed as severe UNE, and 10 (8%) nerves were negative for UNE by EDX. Maximal-maximal CSA was highly correlated with disease severity as determined by nerve conduction studies/electromyography. Compared with EDX+/US+, patients with EDX-/US+ showed higher rates of ulnar sensory loss and elbow tenderness with similar rates of positive Tinel and intrinsic muscle atrophy. In this sample of patients with clinically diagnosed UNE, 91.3% of the patients demonstrated positive EDX studies, whereas 94.8% had a positive US.

CONCLUSIONS

Ultrasound is an alternative to EDX that could be incorporated clinically in the diagnosis and management of UNE. Ultrasound was able to consistently detect clinically positive cubital tunnel syndrome demonstrating its utility as a confirmatory or supplemental test to the clinical assessment if one is required. Ultrasound additionally may be able to better identify patients with early stages of UNE with negative EDX findings.

TYPE OF STUDY/LEVEL OF EVIDENCE

Diagnostic IV.

Use of nerve conduction studies in carpal tunnel syndrome

This review article examines the use of nerve conduction studies in the management of carpal tunnel syndrome. These studies should be understood not as a test that determines the diagnosis but as a measure of impaired nerve function. They are sensitive indicators of local demyelination and axonal loss that can detect and quantify these changes before the appearance of clinical signs, providing information that cannot be obtained with the unaided senses of the physician, nor by any other investigation. They are the best available indicator of overall disease severity, correlating with symptoms and anatomical change in the median nerve. They have some prognostic value for surgical outcome and are sufficiently sensitive to change for the evaluation of treatment response. When surgery does not yield the expected improvement in symptoms, they can help to establish whether decompression has been achieved provided preoperative results are available for comparison.

Sonographic peripheral nerve cross-sectional area in adults, excluding median and ulnar nerves: A systematic review and meta-analysis

INTRODUCTION/AIMS

Although electromyography remains the "gold standard" for assessing and diagnosing peripheral nerve disorders, ultrasound has emerged as a useful adjunct, providing valuable anatomic information. The objective of this study was to conduct a systematic review and meta-analysis evaluating the normative sonographic values for adult peripheral nerve cross-sectional area (CSA).

METHODS

Medline and Cochrane Library databases were systematically searched for healthy adult peripheral nerve CSA, excluding the median and ulnar nerves. Data were meta-analyzed, using a random-effects model, to calculate the mean nerve CSA and its 95% confidence interval (CI) for each nerve at a specific anatomical location (= group).

RESULTS

Thirty groups were identified and meta-analyzed, which comprised 16 from the upper extremity and 15 from the lower extremity. The tibial nerve (n = 2916 nerves) was reported most commonly, followed by the common fibular nerve (n = 2580 nerves) and the radial nerve (n = 2326 nerves). Means and 95% confidence interval (CIs) of nerve CSA for the largest number of combined nerves were: radial nerve assessed at the spiral groove (n = 1810; mean, 5.14 mm2 ; 95% CI, 4.33 to 5.96); common fibular nerve assessed at the fibular head (n = 1460; mean, 10.18 mm2 ; 95% CI, 8.91 to 11.45); and common fibular nerve assessed at the popliteal fossa (n = 1120; mean, 12.90 mm2 ; 95% CI, 9.12 to 16.68). Publication bias was suspected, but its influence on the results was minimal.

DISCUSSION

Two hundred thirty mean CSAs from 15 857 adult nerves are included in the meta-analysis. These are further categorized into 30 groups, based on anatomical location, providing a comprehensive reference for the clinician and researcher investigating adult peripheral nerve anatomy.

Understanding the Learning Curve of Carpal Tunnel Release With Ultrasound Guidance: A Review

Carpal tunnel syndrome (CTS) is the most common compressive neuropathy and can be treated through carpal tunnel release (CTR) if nonoperative treatments fail. CTR can be performed through a variety of techniques, including traditional open, mini-open, endoscopic, and CTR with ultrasound guidance (CTR-US). The evidence on endoscopic CTR is mixed, due to a higher potential for nerve injury with endoscopic CTR compared to traditional open CTR. CTR-US offers the potential advantage of allowing the visualization of all key anatomical structures, combined with a very small incision and minimal soft tissue insult. As with any ultrasonographic technique or procedure, the learning curve needs to be considered for any provider considering adopting CTR-US. However, literature on ultrasound use around the wrist, including early evidence on the learning curve of CTR-US specifically, demonstrates this skill can be learned relatively quickly by providers with a wide range of prior experience in ultrasound and CTR. Overall, there is a need for high-quality studies comparing different CTR techniques, particularly CTR-US, as it offers the potential for considerable cost savings.

Comparison of Diagnostic Accuracy of Electrodiagnostic Testing and Ultrasonography for Carpal Tunnel Syndrome

BACKGROUND

Confirmatory methods such as electrodiagnostic testing (EDX) and ultrasonography (US) are currently used to support a clinical diagnosis of carpal tunnel syndrome (CTS). Scientific consensus long has preferred nerve conduction studies (NCS); however, recent studies have advocated for a diagnostic niche for ultrasound examination. This study seeks to compare diagnostic accuracies, sensitivity, and specificity between these 2 diagnostic tools.

METHODS

An institutional database was retrospectively analyzed to reveal 402 upper extremity cases (265 patients) with potential for CTS diagnosis. Demographics, NCS results, and US findings were determined for each patient case. Sensitivity and specificity values were determined for each diagnostic modality using Carpal Tunnel Syndrome 6 (CTS-6), a validated clinical CTS scoring system, as the reference standard. Demographic and diagnostic values were compared between positive and negative CTS groups using the 2-tailed t test and χ2 test.

RESULTS

Electrodiagnostic testing resulted in a sensitivity of 87% and a specificity of 27%, whereas US produced a sensitivity of 76% and a specificity of 51%. No statistical difference was found in CTS-6 scores between NCS-positive and NCS-negative patient hands, whereas CTS-6 scores were significantly greater in US-positive CTS cases than US-negative cases (15.2 and 13.1, respectively, P < .001).

CONCLUSIONS

Electrodiagnostic testing yields a greater sensitivity for CTS than US examination. However, US testing aligns more closely with CTS-6 scores and results in a greater specificity and positive predictive value. These findings suggest that US holds a non-trivial niche in CTS diagnosis and that EDX is not clearly preferable for all CTS diagnoses and cases.

Potential Relationships between the Median Nerve Cross-Sectional Area and Physical Characteristics in Unilateral Symptomatic Carpal Tunnel Syndrome Patients

Background: The present study investigated the relationships between the median nerve cross-sectional area (CSA) and physical characteristics in patients with unilateral symptomatic carpal tunnel syndrome (CTS). Methods: Height, weight, body mass index (BMI), disease duration, results of electrodiagnostic testing (EDX), and median nerve CSA at the level of the wrist crease were recorded in 81 patients with CTS who presented with symptoms on only one side. Correlation coefficients between median nerve CSA and physical characteristics, disease duration, and results of EDX were analyzed. Results: Median nerve CSA at the wrist crease (mm2) was significantly larger on the symptomatic side (14.1 ± 3.8) than on the asymptomatic side (11.5 ± 2.9). Median nerve CSA correlated with body weight (correlation coefficient = 0.39) and BMI (correlation coefficient = 0.44) on the asymptomatic side, but not on the symptomatic side. These correlations were slightly stronger in females (correlation coefficient = 0.46) than in males (correlation coefficient = 0.40). No correlations between median nerve CSA and disease duration and the results of EDX were observed in both sides. Conclusions: In patients with unilateral symptomatic CTS, median nerve CSA correlated with BMI only on the asymptomatic side. The present results suggest that the relationship between median nerve CSA and BMI in CTS is significant until symptom onset but may be masked by edema and pseudoneuroma after its onset. A higher BMI is associated with a larger CSA of the median nerve, which may be a risk factor for the development of CTS.

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.

Carpal tunnel syndrome: updated evidence and new questions

Carpal tunnel syndrome is the most common entrapment neuropathy, affecting quality of life for many people. Although it is a well recognised condition, new insights into epidemiology, diagnosis, and treatment have emerged in the past 6 years. The availability of disease-modifying treatments for rare systemic disorders associated with carpal tunnel syndrome (eg, amyloidosis) should alert clinicians to these diagnostic possibilities. Besides clinical evaluation and electrophysiology, the role of ultrasonography as a diagnostic tool has been confirmed and new ultrasound techniques have been applied, the clinical use and feasibility of which require further investigation. Surgical and non-surgical interventions are beneficial for the treatment of carpal tunnel syndrome and several treatment options are now available, giving clinicians the possibility to choose the best approach for every patient. New diagnostic and therapeutic techniques require further validation.

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.

Carpal Tunnel Syndrome in Patients with Psoriatic Arthritis: Ultrasonography and Magnetic Resonance Imaging Findings

Objective

The aim of the present study is to assess carpal tunnel syndrome's (CTS's) ultrasonography (US) and magnetic resonance imaging (MRI) findings in patients with psoriatic arthritis (PsA) and compare them with healthy controls.

Methods

Thirty-nine PsA and twenty-eight healthy volunteers were examined in this study. Demographic and clinical features were recorded. CTS-6, a diagnostic algorithm, was used to estimate the probability of CTS. Electrodiagnostic study (EDS) was applied to all wrists included in the report, where the diagnosis of CTS was made by EDS. The cross-sectional area (CSA) of the median nerve was measured at pisiform bone level by US and MRI.

Results

Regarding to the demographic characteristics, no statistically significant difference was found between the groups. Twelve of 39 (30.76%) PsA patients had CTS, whereas CTS was not detected in the control group (p=0.001). US and MRI showed increased median nerve CSA in PsA patients compared to healthy controls (p=0.005, p<0.001; respectively). Also, US and MRI showed increased median nerve CSA in CTS patients compared to others (p=0.002, p<0.001; respectively). The Pearson correlation coefficient between MRI and US measurements of the CSA was 0.85 (p<0.001).

Conclusion

CTS frequency in PsA patients is found higher than healthy controls. The relationship between CTS diagnosed by EDS and CSA measured by both US and MRI was observed in PsA patients.

Future Considerations in the Diagnosis and Treatment of Compressive Neuropathies of the Upper Extremity

Compressive neuropathies of the upper extremity are among the most common conditions seen by hand surgeons. The diagnoses of carpal tunnel syndrome and cubital tunnel syndrome have traditionally been made by a combination of history, physical examination, and electrodiagnostic testing. However, findings can be nonspecific and electrodiagnostic testing is invasive for the patient. The diagnosis of compressive neuropathies continues to evolve as technology advances, and newer diagnostic modalities predominantly focus on preoperative diagnostic imaging with ultrasound and magnetic resonance imaging/neurography. With the advent of cheaper, faster, and less invasive imaging, the future may bring a paradigm shift away from electrophysiology as the gold standard for the preoperative diagnosis of compressive neuropathies. Intraoperative imaging of nerve health is an emerging concept that warrants further investigation, whereas postoperative imaging of nerve recovery with ultrasound and magnetic resonance imaging currently has a limited role because of nonspecific findings and potential for misinterpretation. Advances in surgical treatment of compressive neuropathies appear to center around the use of imaging for less invasive neurolysis techniques and other adjunctive treatments with nerve decompression. The management of failed peripheral nerve decompressions and recurrent compressive neuropathies remains challenging.

High-resolution ultrasound of peripheral neuropathies in rheumatological patients: An overview of clinical applications and imaging findings

Peripheral neuropathies are surprisingly common and can be associated with a number of conditions, including rheumatological diseases. Whether the co-existence of peripheral neuropathies with rheumatological disorders is coincidental or related to a common pathogenic mechanism, these disabling conditions can affect the outcome of rheumatological patients and should be targeted with specific treatment. The clinical presentation of peripheral neuropathy can be multifaceted and difficult to recognize in polysymptomatic patients. However, physicians adopting state-of-art diagnostic strategies, including nerve imaging, may improve the detection rate and management of neuropathies. In particular, a diagnostic approach relying exclusively on clinical history and nerve conduction studies may not be sufficient to disclose the etiology of the nerve damage and its anatomical location and thus requires integration with morphological studies. High-Resolution Ultrasound (HRUS) is increasingly adopted to support the diagnosis and follow-up of both joint disorders in rheumatology and peripheral neuropathies of different etiologies. In this review, the different types of nerve disorders associated with the most common syndromes of rheumatological interest are discussed, focusing on the distinctive sonographic features.

A Novel Ultrasonographic Anthropometric-Independent Measurement of Median Nerve Swelling in Carpal Tunnel Syndrome: The "Nerve/Tendon Ratio" (NTR)

Background: There is little consensus on ultrasound (US) normative values of cross-sectional area of median nerve (MN-CSA) in carpal tunnel syndrome (CTS) because of its dependency on anthropometric parameters. We aim to propose a novel anthropometric-independent US parameter: MN-CSA/flexor radialis carpi CSA (FCR-CSA) ratio (“Nerve Tendon Ratio”, NTR), in the diagnosis of clinically and electrodiagnostic (EDS)-defined CTS. Methods: 74 wrists of 49 patients with clinically defined CTS underwent EDS (scored by the 1−5 Padua Scale of electrophysiological severity, PS) and US of carpal tunnel with measurement of MN-CSA (at the carpal tunnel inlet), FCR-CSA (over scaphoid tubercle) and its ratio (NTR, expressed as a percentage). US normality values and intra-operator agreement were assessed in 33 healthy volunteers. Results: In controls, the mean MN-CSA was 5.81 mm2, NTR 64.2%. In 74 clinical CTS, the mean MN-CSA was 12.1 mm2, NTR 117%. In severe CTS (PS > 3), the mean MN-CSA was 15.9 mm2, NTR 148%. In CTS, both MN-CSA and NTR correlated with sensitive conduction velocity (SCV) (p < 0.001), distal motor latency (DML) (p < 0.001) and PS (p < 0.001), with a slight superiority of NTR vs. MN-CSA when controlled for height, wrist circumference and weight. In CTS filtered for anthropometric extremes, only NTR maintained a correlation with SCV (p = 0.023), DML (p = 0.016) and PS (p = 0.009). Diagnostic cut-offs were obtained with a binomial regression analysis. In those patients with a clinical diagnosis of CTS, the cut-off of MN-CSA (AUROC: 0.983) was 8 mm2 (9 mm2 with highest positive predictive value, PPV), while for NTR (AUROC: 0.987), the cut-off was 83% (100% with highest PPV). In patients with EDS findings of severe CTS (PS > 3), the MN-CSA (AUROC: 0.876) cut-off was 12.3 mm2 (15.3 mm2 with highest PPV), while for NTR (AUROC: 0.858) it was 116.2% (146.0% with highest PPV). Conclusions: NTR can be simply and quickly calculated, and it can be used in anthropometric extremes.

Ultrasonography for the diagnosis of carpal tunnel syndrome: an umbrella review

BACKGROUND

Numerous sonographic modalities and parameters have been used to diagnose carpal tunnel syndrome (CTS), with varying accuracy. Our umbrella review aimed to summarize the evidence from systematic reviews and meta-analyses regarding the use of ultrasound imaging to diagnose CTS.

METHODS

Systematic reviews and meta-analyses meeting the inclusion criteria were searched in PubMed, Embase, Medline, Web of Science, and Cochrane databases from inception to March 2022. Critical appraisal, data extraction, and synthesis were performed in accordance with the criteria for conducting an umbrella review.

RESULTS

Sixteen reviews were included. Three reviews were classified as high quality, one as moderate, four as low, and eight as critically low. The cross-sectional area (CSA) of the median nerve at the carpal tunnel inlet demonstrated the best reliability and diagnostic accuracy among multiple parameters. A cutoff CSA value of 9-10.5 mm2 gave the highest diagnostic performance in the general population. The degree of CSA enlargement was correlated with CTS severity. Sonoelastography and Doppler ultrasound might provide additional insights into CTS evaluation as median nerve stiffness and vascularity at the wrist were increased in these patients.

CONCLUSIONS

Sonography is a reliable tool to diagnose CTS, with inlet CSA being the most robust parameter. Sonoelastography and Doppler ultrasound can serve as auxiliary tools to confirm CTS diagnoses. Further studies are needed to expand the use of sonography for diagnosing CTS, especially in the presence of concomitant neuromuscular disease(s).

Occupational hand and wrist disorders among forestry workers: An exposed-control study to investigate preventive strategies

BACKGROUND: In the arboriculture sector, some activities are still manually performed by forestry workers, which result consequently exposed to a high risk of developing muscle skeletal disorders. The Italian Compensation Authority reported an increase of work-related tendinopathies and carpal tunnel syndrome in loggers, but screening protocols are not available yet. OBJECTIVES: The objectives were: a) to evaluate the prevalence of tendinopathies and carpal tunnel syndrome in a sample of loggers and b) identify a sound screening approach. METHODS: 41 loggers and 41 paired control workers were recruited for a total of 164 hands. The protocol included 1) demographic data; 2) medical history; 3) identification of CTS symptoms through a questionnaire and a hand-chart; 4) upper limbs clinical examination; 5) Raynaud’s diseases questionnaire; 6) wrists ultrasound; 7) NCS of the distal median nerve. RESULTS: The prevalence of tendinopathies was statistically significant only in the non-dominant hand (75, 5% in the exposed group and 53, 6% in the non-exposed group). The prevalence of CTS was 32, 2% in the exposed group and 15, 5% in the non-exposed group. The questionnaire had a sensitivity of 56, 7% and a specificity of 75%. The hand-chart had a sensitivity of 30% and a specificity of 92%. The clinical examination had sensitivity of 30% and specificity of 80%. The ultrasound had a sensitivity of 70% and a specificity of 56%. CONCLUSIONS: Loggers are a population at risk of occupational hand and wrist disorders. The hand-chart could be considered, together with the questionnaire, as the best secondary prevention tool to diagnose CTS.

Accuracy of the Most Common Provocation Tests for Diagnosing Carpal Tunnel Syndrome: A Systematic Review With Meta-analysis

OBJECTIVE

To estimate the screening performances of the most important provocation tests for diagnosing carpal tunnel syndrome (CTS).

DESIGN

Diagnostic test accuracy systematic review with meta-analysis.

LITERATURE SEARCH

We systematically searched the MEDLINE, Scopus, Web of Science, and Cochrane databases from inception to November 2020.

STUDY SELECTION CRITERIA

Observational studies comparing the accuracies of the Durkan test (DT), the hand elevation test (HET), the Phalen test (PT), the Tinel test (TT), and the upper-limb neurodynamic test specific to the median nerve (ULNT1) with electrodiagnosis for screening for CTS.

DATA SYNTHESIS

Random-effects models for the diagnostic odds ratio (dOR) values computed by Moses' constant for a linear model and 95% confidence intervals (CIs) were used to calculate the accuracy of these tests. Hierarchical summary receiver operating characteristic curve analyses were used to summarize the overall test performance.

RESULTS

Thirty-seven studies were included in the meta-analysis, with a total sample of 2662 wrists for DT, 864 wrists for HET, 6361 wrists for PT, 6094 wrists for TT, and 571 wrists for ULNT1. The pooled dORs for screening for CTS were 15.84 (95% CI: 3.78, 66.38) for DT, 128.63 (95% CI: 40.64, 407.12) for HET, 7.23 (95% CI: 4.06, 12.86) for PT, 5.31 (95% CI: 3.49, 8.09) for TT, and 1.78 (95% CI: 0.61, 5.19) for ULNT1.

CONCLUSION

HET has the best clinical performance for detecting CTS and should be considered the first screening test of choice during the physical examination. The most common tests (DT, PT, and TT) have good accuracies for screening for CTS. J Orthop Sports Phys Ther 2022;52(8):522-531. Epub: 19 June 2022. doi:10.2519/jospt.2022.10828.

The role of diagnostic ultrasound in the examination of carpal tunnel syndrome: an update and systematic review

BACKGROUND

Diagnostic ultrasound is becoming more available and has potential for identifying carpal tunnel syndrome (CTS), but there is a lack of consensus on optimal measurement parameters and interpretation.

PURPOSE

The purpose of this systematic review was to analyze and summarize recent published data evaluating measurement properties of diagnostic ultrasound for use in individuals with CTS.

METHODS

Five databases were searched to identify studies reporting on diagnostic measurement in individuals ≥18 years of age. Thirty-four studies underwent critical appraisal using Center for Evidence Based Medicine guidelines for diagnostic study accuracy. Each team member independently reviewed and scored the studies and consensus was reached through discussion.

RESULTS

Seventeen studies evaluating 21 unique nerve or tunnel measurements and 9 measurement ratios were included. Measurements of median nerve cross sectional area (CSA) taken at the carpal tunnel inlet consistently demonstrated good to excellent interrater reliability (ICC=0.83-0.93) and good intrarater reliability (r>0.81). All studies supported inlet CSA in differentiating between individuals with and without CTS. Carpal tunnel inlet CSA measurements demonstrated a moderate correlation to the Padua severity classification (r = 0.71), but this varied between studies. Diagnostic accuracy of CSA measured at the carpal tunnel inlet using diagnostic cutoff values ranging from 8.5 mm² to 12.6 mm² resulted in a range sensitivity (63%-96.9%) and specificity (67.9%-100%).

CONCLUSION

The US measurement most supported was the median nerve CSA measured at the carpal tunnel inlet. There was no evidence supporting the routine use of diagnostic US for individuals with suspected CTS, and no additional evidence to support replacement of electrodiagnostic studies by US. More research is needed to determine use of US for classifying CTS severity or as a differential diagnostic tool for conditions that mimic CTS.

LEVEL OF EVIDENCE

N/A.

Common Hand Conditions: A Review

Importance

Carpal tunnel syndrome, trigger finger, de Quervain tenosynovitis, and basilar (carpometacarpal) joint arthritis of the thumb can be associated with significant disability.

Observations

Carpal tunnel syndrome is characterized by numbness and tingling in the thumb and the index, middle, and radial ring fingers and by weakness of thumb opposition when severe. It is more common in women and people who are obese, have diabetes, and work in occupations involving use of keyboards, computer mouse, heavy machinery, or vibrating manual tools. The Durkan physical examination maneuver, consisting of firm digital pressure across the carpal tunnel to reproduce symptoms, is 64% sensitive and 83% specific for carpal tunnel syndrome. People with suspected proximal compression or other compressive neuropathies should undergo electrodiagnostic testing, which is approximately more than 80% sensitive and 95% specific for carpal tunnel syndrome. Splinting or steroid injection may temporarily relieve symptoms. Patients who do not respond to conservative therapies may undergo open or endoscopic carpal tunnel release for definitive treatment. Trigger finger, which involves abnormal resistance to smooth flexion and extension ("triggering") of the affected finger, affects up to 20% of adults with diabetes and approximately 2% of the general population. Steroid injection is the first-line therapy but is less efficacious in people with insulin-dependent diabetes. People with diabetes and those with recurrent symptoms may benefit from early surgical release. de Quervain tenosynovitis, consisting of swelling of the extensor tendons at the wrist, is more common in women than in men. People with frequent mobile phone use are at increased risk. The median age of onset is 40 to 59 years. Steroid injections relieve symptoms in approximately 72% of patients, particularly when combined with immobilization. People with recurrent symptoms may be considered for surgical release of the first dorsal extensor compartment. Thumb carpometacarpal joint arthritis affects approximately 33% of postmenopausal women, according to radiographic evidence of carpometacarpal arthritis. Approximately 20% of patients require treatment for pain and disability. Nonsurgical interventions (immobilization, steroid injection, and pain medication) relieve pain but do not alter disease progression. Surgery may be appropriate for patients unresponsive to conservative treatments.

Conclusions and Relevance

Carpal tunnel syndrome, trigger finger, de Quervain tenosynovitis, and thumb carpometacarpal joint arthritis can be associated with significant disability. First-line treatment for each condition consists of steroid injection, immobilization, or both. For patients who do not respond to noninvasive therapy or for progressive disease despite conservative therapy, surgical treatment is safe and effective.

Diagnostic Value of Ultrasound for Detecting Carpal Tunnel Syndrome in Patients With Rheumatoid Arthritis: A Three-Arm Cross-Sectional Study

Objective:

This study was conducted to assess the diagnostic value of sonography in detecting carpal tunnel syndrome (CTS) in patients with rheumatoid arthritis (RA) and to compare the results with a normal control group.

Materials and Methods:

In this three-arm cross-sectional study, the sonographically measured median nerve cross-sectional area (MNCSA) was compared in three groups: RA patients with CTS, RA patients without CTS, and normal subjects (no RA, no CTS). A nerve conduction study (NCS) was performed for all enrolled participants, across the three study arms.

Results:

In this study, 38 RA patients (17 in CTS group and 21 in no CTS group) and 19 healthy subjects were recruited. The MNCSAs were 11.86 (±1.87) mm2 in RA patients with CTS, 10.16 (±1.71) mm2 in RA patients without CTS, and 9.42 (±1.46) mm² in healthy control patients. The accuracy of sonography in detecting CTS was 0.79 (95% confidence interval, 0.67–0.91), with a sensitivity and specificity of 88% and 57%, respectively. The MNCSA in CTS group was significantly higher than the control group ( P = .02).

Conclusion:

In this cohort, the sonographic measurement of MNCSA was an accurate and sensitive method for the diagnosis of CTS, especially in its early stages. In addition, in this cohort, RA without CTS did not increase the MNCSA.

Ultrasonography for the diagnosis of carpal tunnel syndrome: correlation of clinical symptoms, cross-sectional areas and electroneuromyography

This study evaluates the usefulness of ultrasonography in diagnosing carpal tunnel syndrome (CTS). The cross-sectional area of the median nerve was measured at the forearm and its entry into the carpal tunnel and compared with clinical symptoms and electroneuromyography. A total of 124 patients were examined, 77 patients with clinically confirmed CTS and 47 controls. A significant correlation was found between the ultrasonography cross-sectional area values at entry points into the carpal tunnel and electroneuromyography. The highest sensitivity (87%) and specificity (91%) for different cut-off values (8.5-12.5 mm²) of the cross-sectional area was for 11.5 mm². The use of ultrasonography may provide a quick and reliable differential diagnostic tool for the primary diagnosis of CTS in patients with classical symptoms.Level of evidence: II.

Neuromuscular Ultrasound: Indications in the Electrodiagnostic Laboratory

ABSTRACT

Accurate assessment of neuromuscular disorders is critical to facilitate timely treatment and achieve the best outcomes. Historically, electrodiagnostic studies have filled this role, but recently, neuromuscular ultrasound is being used in the electrodiagnostic laboratory. This review discusses the uses of neuromuscular ultrasound in the electrodiagnostic laboratory that have strong evidence, emphasizing those that could be adopted in a typical electrodiagnostic laboratory with a reasonable level of equipment and training. The evidence currently supports using neuromuscular ultrasound to diagnose carpal tunnel syndrome and ulnar neuropathies at the elbow and as a supplementary test when electrodiagnostic studies are suspected to be falsely negative or in axonal nonlocalizing lesions. Neuromuscular ultrasound can identify the causes of focal mononeuropathies, which can change treatment in specific cases. It is sensitive at identifying fasciculations and providing complementary evidence of autoimmune demyelinating polyneuropathies. It is particularly helpful in assessing nerves after trauma. Neuromuscular ultrasound is likely to prove even more useful in the electrodiagnostic laboratory as the technology continues to advance.

Diagnosis of carpal tunnel syndrome in non-diabetic patients with hemodialysis using ultrasound: Is it a useful adjunctive tool?

OBJECTIVE

(1) To examine the ultrasound (US) characteristics in patients with hemodialysis-related carpal tunnel syndrome (H-CTS) and (2) to evaluate the accuracy of a proposed US parameter-dynamic ratio of median nerve-to-hamate hook distance (RMHD) in diagnosis of H-CTS.

DESIGN

A case-control study.

SETTING

In a tertiary medical center and a secondary hospital from Nov. 2017 to Mar. 2021.

PARTICIPANTS

Consecutive non-diabetes patients under hemodialysis were recruited and divided into a hemodialysis without CTS (H-Control) group and an H-CTS group. Age-matched volunteers without diabetes or upper extremity disorders were enrolled as the Control group.

INTERVENTION

Ultrasound examinations by two operators blinded to the patient's clinical information.

MAIN OUTCOME MEASURES

US parameters including cross-sectional area of the median nerve at the carpal tunnel inlet (CSA-I) and outlet (CSA-O), the flattening ratio of the median nerve at the inlet (FR-I) and outlet (FR-O), and RMHD.

RESULTS

Handedness and arteriovenous fistula showed no associations with CSA-I/O and FR-I/O. Compared with Control group (n=69), the CSA-I was significantly larger in the H-Control group (n=63) and H-CTS group (n=76) (p<0.05). There were no significant differences in the FR-I/-O among the three groups. For the second aim, in the H-CTS group(n=38), there was a significantly lower RMHD compared with both the Control (n=20) and H-Control groups (n=30) (0.1%±2.2% versus 3.5±2.3% and 3.8±1.7%, p<0.05). An RMHD cutoff value of <2.7% yielded a specificity of 80.0%, a sensitivity of 94.7%, and an overall accuracy of 88.2% in the diagnosis of H-CTS.

CONCLUSIONS

Neither CSA-I/-O or FR-I/-O have a role in the diagnosis of H-CTS. RMHD might be a useful US parameter in the diagnosis of CTS in non-diabetic patients undergoing hemodialysis.

Meta-analysis of the normal diffusion tensor imaging values of the median nerve and how they change in carpal tunnel syndrome

Carpal tunnel syndrome (CTS) leads to distortion of axonal architecture, demyelination and fibrosis within the median nerve. Diffusion tensor imaging (DTI) characterises tissue microstructure and generates reproducible proxy measures of nerve 'health' which are sensitive to myelination, axon diameter, fiber density and organisation. This meta-analysis summarises the normal DTI values of the median nerve, and how they change in CTS. This systematic review included studies reporting DTI of the median nerve at the level of the wrist in adults. The primary outcome was to determine the normal fractional anisotropy (FA) and mean diffusivity (MD) of the median nerve. Secondarily, we show how the FA and MD differ between asymptomatic adults and patients with CTS, and how these differences are independent of the acquisition methods. We included 32 studies of 2643 wrists, belonging to 1575 asymptomatic adults and 1068 patients with CTS. The normal FA was 0.58 (95% CI 0.56, 0.59) and the normal MD was 1.138 × 10^-3 mm²/s (95% CI 1.101, 1.174). Patients with CTS had a significantly lower FA than controls (mean difference 0.12 [95% CI 0.09, 0.16]). Similarly, the median nerve of patients with CTS had a significantly higher mean diffusivity (mean difference 0.16 × 10^-3 mm²/s [95% CI 0.05, 0.27]). The differences were independent of experimental factors. We provide summary estimates of the normal FA and MD of the median nerve in asymptomatic adults. Furthermore, we show that diffusion throughout the length of the median nerve becomes more isotropic in patients with CTS.

Automated Segmentation of Median Nerve in Dynamic Sonography Using Deep Learning: Evaluation of Model Performance

There is an emerging trend to employ dynamic sonography in the diagnosis of entrapment neuropathy, which exhibits aberrant spatiotemporal characteristics of the entrapped nerve when adjacent tissues move. However, the manual tracking of the entrapped nerve in consecutive images demands tons of human labors and impedes its popularity clinically. Here we evaluated the performance of automated median nerve segmentation in dynamic sonography using a variety of deep learning models pretrained with ImageNet, including DeepLabV3+, U-Net, FPN, and Mask-R-CNN. Dynamic ultrasound images of the median nerve at across wrist level were acquired from 52 subjects diagnosed as carpal tunnel syndrome when they moved their fingers. The videos of 16 subjects exhibiting diverse appearance and that of the remaining 36 subjects were used for model test and training, respectively. The centroid, circularity, perimeter, and cross section area of the median nerve in individual frame were automatically determined from the inferred nerve. The model performance was evaluated by the score of intersection over union (IoU) between the annotated and model-predicted data. We found that both DeepLabV3+ and Mask R-CNN predicted median nerve the best with averaged IOU scores close to 0.83, which indicates the feasibility of automated median nerve segmentation in dynamic sonography using deep learning.

Ultrasound-Guided Triamcinolone Acetonide Hydrodissection for Carpal Tunnel Syndrome: A Randomized Controlled Trial

Background: Despite the wide use of corticosteroid hydrodissection for carpal tunnel syndrome (CTS), there is insufficient evidence to confirm its efficacy. This study aimed to compare the effectiveness of corticosteroid hydrodissection vs. corticosteroid perineural injection alone on clinical and electrophysiological parameters in patients with CTS. Method: This prospective randomized controlled trial (RCT) was conducted in a tertiary care center with a follow-up period of 12 weeks. Subjects were randomly assigned to either ultrasound-guided hydrodissection with a mixture of 1 mL of triamcinolone acetonide (10 mg/mL), 1 mL of 2% lidocaine, and 8 mL normal saline or ultrasound-guided perineural injection with 1 mL of triamcinolone acetonide (40 mg/mL) and 1 mL of 2% lidocaine. The primary outcome measure was the symptom severity subscale (SSS) of Boston Carpal Tunnel Questionnaire (BCTQ) scores at baseline and at 6 and 12 weeks' post-treatment. The secondary outcomes included the functional status subscale (FSS) of BCTQ and the distal motor latency and sensory nerve conduction velocity of the median nerve. The effect of interventions on the designated outcome was analyzed using a 3 × 2 repeated measures analysis of variance. The within-subject and among-subject factors were differences in time (before the intervention, and 6 and 12 weeks after injection) and intervention types (with or without hydrodissection), respectively. Results: Sixty-four patients diagnosed with CTS were enrolled. Both groups experienced improvement in the SSS and FSS of BCTQ and median nerve distal motor latency and sensory nerve conduction velocity. However, group-by-time interactions were not significant in any outcome measurements. No serious adverse events were reported in either group, except for two patients in the hydrodissection group who reported minor post-injection pain on the first day after the intervention, which resolved spontaneously without the need for additional treatments. Conclusion: Hydrodissection did not provide an additional benefit compared to corticosteroid perineural injection alone. More prospective studies are needed to investigate the long-term effectiveness of corticosteroid hydrodissection, as well as its influence on median nerve mobility.

Dynamic Ultrasound Assessment of Median Nerve Mobility Changes Following Corticosteroid Injection and Carpal Tunnel Release in Patients With Carpal Tunnel Syndrome

Decreased median nerve (MN) mobility was found in patients with carpal tunnel syndrome (CTS) and was inversely associated with symptom severity. It is unclear whether MN mobility can be restored with interventions. This study compared the changes in MN mobility and clinical outcomes after interventions. Forty-six patients with CTS received an injection (n = 23) or surgery (n = 23). Clinical outcomes [Visual Analogue Scale; Boston Carpal Tunnel Questionnaire (BCTQ), which includes the Symptom Severity Scale and Functional Status Scale; median nerve cross-sectional area; and dynamic ultrasound MN mobility parameters (amplitude, and R² value and curvature of the fitted curves of MN transverse sliding)] were assessed at baseline and 12 weeks after the interventions. At baseline, the BCTQ-Functional Status Scale and median nerve cross-sectional area showed significant inter-treatment differences. At 12 weeks, both treatments had significant improvements in BCTQ-Symptom Severity Scale and Visual Analogue Scale scores and median nerve cross-sectional area, but with greater improvements in BCTQ-Functional Status Scale scores observed in those who received surgery than in those who received injections. MN mobility was insignificantly affected by both treatments. The additional application of dynamic ultrasound evaluation may help to discriminate the severity of CTS initially; however, its prognostic value to predict clinical outcomes after interventions in patients with CTS is limited.

"Physiological localization by sensory and motor inching studies and structural abnormalities detected by ultrasonographic changes in carpal tunnel syndrome"

OBJECTIVE

To study mild to moderate carpal tunnel syndrome (CTS), compare median nerve entrapment sites detected by electrophysiologic inching studies with ultrasonographic abnormalities of cross-sectional area (CSA), and correlate focal points of conduction delays detected by sensory and motor inching recorded from the third digit and second lumbrical muscle DESIGN: Analytic cross-sectional study SETTING: Department of Rehabilitation Medicine, King Chulalongkorn Memorial Hospital.

PARTICIPANTS

A total of 15 normal hands from 10 healthy participants and 40 hands with mild to moderate CTS from 29 participants were selected by convenience sampling.

INTERVENTIONS

Not applicable MAIN OUTCOME MEASURE: Correlation of electrophysiologic entrapment site localization by inching study with anatomical entrapment site detected by ultrasound (US).

RESULTS

In all 40 hands tested, a sharply localized latency was found to increase across a 1 cm segment, most commonly 2-3 cm distal to the distal wrist crease for both sensory and motor studies, showing a good match between the two with Pearson correlation coefficient value, r = 0.72. The US revealed a narrowing CSA of the median nerve at 1-2 cm distal to the distal wrist crease.

CONCLUSIONS

This study showed a high correlation for focal point conduction delay detected by sensory and motor nerve conduction study. Recording from the second lumbricalis facilitated motor inching along the straight course of the nerve instead of the arcuate recurrent branch innervating the abductor pollicis brevis, the muscle traditionally used. US examination also revealed a localized narrowing of the median nerve CSA at 1-2 cm distal to the distal wrist crease, a possible site for anatomical entrapment. The most enlarged CSA was seen at the distal wrist crease, a level corresponding to the inlet of the carpal tunnel.

THAI CLINICAL TRIALS REGISTRY NUMBER

TCTR20190605001.

Hand-Wrist Disorders in Chainsaw Operators: A Follow-Up Study in a Group of Italian Loggers

Despite the mechanization process implemented in arboriculture, logging tasks are still manually performed by chainsaw operators, which therefore are exposed to the risk of developing hand-wrist musculoskeletal disorders. Our research aimed to: (a) define whether the slight changes observed in 2017 showed an evolution to overt diseases; (b) study some risk determinants for these diseases such as age, working experience, and performing a secondary job. We recruited in a two-year follow-up study, 38 male forestry workers performing logging tasks employed in the Sicilian Forestry Department located in Enna. All the subjects underwent: (1) personal data collection; (2) administration of questionnaire addressed at upper limbs symptoms with a hand chart; (3) physical examination of the upper limbs, including Tinel’s and Phalen’s maneuvers; (4) ultrasound investigation of the hand-wrist area. In the two-year follow-up study we registered an overall increasing in wrist disorders, thus we can assume that forestry workers may be a target population for wrist diseases and deserve a particular attention in workers’ health surveillance programs. Interestingly, the prevalence of wrist-hand disorders resulted to be higher in younger workers.

The Neurophysiological Severity of Carpal Tunnel Syndrome Cannot Be Predicted by Median Nerve Cross-Sectional Area and Wrist-to-Forearm Ratio

PURPOSE

The median nerve cross-sectional area at the wrist (CSA) and the wrist-to-forearm ratio of the cross-sectional areas (WFR) are ultrasound parameters used in the diagnosis and grading of carpal tunnel syndrome. This study aimed to determine the diagnostic accuracy of the CSA and WFR as well as to compare their diagnostic value.

METHODS

A retrospective evaluation was conducted of a cohort of 218 patients who had undergone nerve conduction studies (NCSs) and an ultrasound of the median nerve. The examined wrists were classified into an NCS negative and three NCS positive (mild, moderate, and severe) categories. The CSA and WFR were compared across the categories.

RESULTS

The CSA and WFR were significantly smaller in the NCS negative category than in the NCS positive categories. The WFR was significantly smaller in the mild category than in the moderate category. The CSA could not be used to differentiate across the NCS positive categories.

CONCLUSIONS

The CSA and WFR are satisfactorily reliable in detecting carpal tunnel syndrome, but they cannot be considered as surrogate indicators of electrophysiological severity.

The treatment effect of intramuscular stimulation on carpal tunnel syndrome: A blinded randomized trial on 75 patients

BACKGROUND

Carpal tunnel syndrome (CTS) is a disorder with a prevalence of about 5.8% for females and 0.6% for males. This study aims to determine whether intramuscular stimulation (IMS) to the pronator teres muscle subsequently reduces the severity of clinical parameters and the diameter of the median nerve.

METHODS

Seventy-five individuals with a cross-sectional diameter of the median nerve of more than 2 mm were included in this randomized clinical trial. Thirty-seven individuals received IMS to the pronator teres muscle with a depth of up to 45-50 mm. The 38 individuals in the control group received an acupuncture needle at Li11 with a depth of 4-5 mm. Both groups had 7 treatments within 7 weeks. The primary outcome was the cross-section of the median nerve in the carpal tunnel. Additionally, Phalen's test, Tinel's sign, VAS for pain intensity, and pincer grip strength were measured.

RESULTS

Both IMS subjects and controls showed significant reductions in the cross-section of the median nerve from baseline to follow-up (p < 0.001 and p = 0.002 respectively). The IMS group had the largest change, but the difference in change between the groups was not significant (p = 0.39). On all clinical tests, IMS subjects showed significant improvement from baseline compared with the control group (largest p = 0.002).

CONCLUSION

In this study we found that IMS to the pronator teres muscle significantly improved all clinical variables measured, compared with the group receiving acupuncture. Furthermore, the cross-section of the median nerve reduced over time for both groups. IMS may be a low-risk alternative while patients are waiting for surgery.

TRIAL REGISTRATION

Clinicaltrials. gov Identifier: NCT01102868. Retrospectively registered: March 29th^, 2010.

A systematic review of the methodology of sonographic assessment of upper limb activities-associated carpal tunnel syndrome

BACKGROUND

Various upper limb activities were speculated to be associated with the development of carpal tunnel syndrome (CTS). Nonetheless, there are currently no standardization on the uses of parameters in CTS assessments, nor are there any conclusive findings regarding the usefulness of various sonographic measurements in studies of different upper limb activities. In this review, we intend to evaluate the methodology of assessing CTS induced by upper limb activities with ultrasonographic technique and provide corresponding suggestions.

METHODS

Clinical studies on the association between upper limb activities and prevalence of CTS using ultrasonography were recruited in a database research on the basis of a procedural selection criteria and reviewed. The following qualitative items were extracted: characteristics of studies, scanning methods, selection of sonographic parameters, and related article findings.

RESULTS

Eleven studies were qualified for this review. Three studies were computer keyboard typing related, five studies were electronic device related, and three studies were wheelchair-related. All sampled articles included cross-sectional area (CSA) at the pisiform level. The swelling ratio (SR) and flattening ratio (FR) at the hamate level are also used in most studies in addition to the CSA at the pisiform level. The effectiveness of such parameters is subjected to various confounding factors such as age, weight, body mass index, and wrist anthropometrics, suggesting CSA and SR with sufficient levels had significant values as sonographic parameters. Values of parameters were found affecting symptomatic signs and hand dominance.

CONCLUSION

Ultrasound scan is a suitable tool to assess the relationship between upper limb activity and CTS. CSA at the pisiform level and SR and the FR at the hamate levels are generally suitable in upper limb-associated CTS investigations. Specific study designs are required to eliminate different confounding factors accordingly.