Diagnosing carpal tunnel syndrome—clinical criteria and ancillary tests

Comparison of the Effect of Intracarpal Injection of Ketorolac With Triamcinolone in Carpal Tunnel Syndrome: A Randomized Controlled Trial

BACKGROUND

The most prevalent entrapment neuropathy is carpal tunnel syndrome (CTS). Although nonsteroidal antiinflammatory drugs (NSAIDs) are frequently prescribed for musculoskeletal disorders, oral NSAIDs do not provide any additional benefits for CTS. Nevertheless, the use of NSAID phonophoresis has shown significant improvement, possibly due to increased concentration in the target tissue. The effects of intracarpal injection of NSAIDs on CTS have not been studied.

OBJECTIVE

We conducted a controlled trial to compare the efficacy of ketorolac and triamcinolone in treating CTS.

METHODS

Mild to moderate CTS patients were randomly assigned to receive either a local injection of 30 mg ketorolac or 40 mg triamcinolone. Patients were evaluated using visual analog scale (VAS) for pain, severity, function, electrodiagnostic findings, patient satisfaction, and any complications at the injection site, at baseline and 12 weeks after the procedures.

RESULTS

Fifty patients participated, and 43 completed the study. Both groups showed significant improvement in the VAS, severity, function, and electrodiagnostic scores at 3 months compared with the baseline. A comparison of the groups showed significant differences in VAS, severity, and function, with the improvement being significantly higher in the triamcinolone group.

CONCLUSION AND RELEVANCE

The present study showed that injection of triamcinolone or ketorolac into the carpal tunnel relieved pain, increased function, and improved electrodiagnostic findings in patients with mild to moderate CTS. It also showed that triamcinolone was superior to ketorolac in terms of analgesic effect and resulted in greater improvement in symptom severity and function.

Measuring tactile sensitivity and mixed-reality-assisted exercise for carpal tunnel syndrome by ultrasound mid-air haptics

Introduction

Carpal tunnel syndrome (CTS) is the most common nerve entrapment neuropathy, which causes numbness and pain in the thumb, the index and middle fingers and the radial side of the ring finger. Regular hand exercises may improve the symptoms and prevent carpal tunnel surgery. This study applied a novel ultrasonic stimulation method to test tactile sensitivity in CTS and also a mixed-reality-assisted (MR-assisted) exercise program which measured hand movements and provided haptic feedback for rehabilitation.

Methods

Twenty patients with mild unilateral CTS took part in the experiments. A mid-air haptics device (Ultrahaptics STRATOS Explore) was used to apply amplitude-modulated ultrasound waves (carrier frequency: 40 kHz) onto the skin to create tactile stimulation mechanically. Participants performed a two-alternative forced-choice task for measuring tactile thresholds at 250-Hz modulation frequency. They were tested at the index fingers and the thenar eminences of both hands. Additionally, 15 CTS patients used an MR-assisted program to do hand exercises with haptic feedback. Exercise performance was assessed by calculating errors between target and actual hand configurations. System Usability Scale (SUS) was adopted to verify the practical usability of the program.

Results

Thresholds at the thenar eminences of the affected and healthy hands were not significantly different. While the thresholds at the healthy index fingers could be measured, those of the affected fingers were all higher than the stimulation level produced by the maximum output from the ultrasound device. In the exercise program, a significant positive correlation (ρ = 0.89, p < 0.001) was found between the performance scores and the SUS scores, which were above the criterion value established in the literature.

Discussion

The results show that thenar tactile sensitivity is not affected in mild CTS as expected from the palmar cutaneous branch of the median nerve (PCBm), but index finger threshold is likely to be higher. Overall, this study suggests that mid-air haptics, with certain improvements, may be used as a preliminary test in the clinical setting. Moreover, the device is promising to develop gamified rehabilitation programs and for the treatment follow-up of CTS.

The Rise Slope of the Compound Sensory Nerve Action Potential in Normal and Pathological Human Nerves

In spite of the diagnostic importance of the early phase of the sensory nerve action potential (SNAP), reliable electrodiagnostic metrics for this part of the recorded waveform are lacking. The average rise slope of the SNAP appreciates the steepness of the initial negative deflection of the waveform, which might be a useful metric for the first part of the potential. Sural nerve sensory neurography was performed in patients with various axonal neuropathies, and median nerve sensory studies were carried out in patients with carpal tunnel syndrome. Age-matched healthy individuals served as controls. The rise slope was compared to conventional SNAP parameters such as conduction velocity, latency, duration, and rise time. Overall, 537 sensory studies were prospectively analyzed. The rise slope of the sural SNAP demonstrated superior classification performance in terms of sensitivity (92.5%), specificity (97%), and area under the receiver operating characteristic curve (0.986), as compared to conventional SNAP parameters. Its diagnostic power was similarly excellent in median nerve studies, whereas here a slightly better classification performance was obtained by SNAP latency and conduction velocity. The average rise slope appears to do justice to the tight interplay between amplitude and rise time of the initial negative spike deflection, outperforming many conventional measures. This composite metric proved high diagnostic potency in particular with regard to axonal sensory nerve dysfunction.

Application of ultrasound images-based radiomics in carpal tunnel syndrome: Without measuring the median nerve cross-sectional area

PURPOSE

By constructing a prediction model of carpal tunnel syndrome (CTS) based on ultrasound images, it can automatically and accurately diagnose CTS without measuring the median nerve cross-sectional area (CSA).

METHODS

A total of 268 wrists ultrasound images of 101 patients diagnosed with CTS and 76 controls in Ningbo NO.2 Hospital from December 2021 to August 2022 were retrospectively analyzed. The radiomics method was used to construct the Logistic model through the steps of feature extraction, feature screening, reduction, and modeling. The area under the receiver operating characteristic curve was calculated to evaluate the performance of the model, and the diagnostic efficiency of the radiomics model was compared with two radiologists with different experience.

RESULTS

The 134 wrists in the CTS group included 65 mild CTS, 42 moderate CTS, and 17 severe CTS. In the CTS group, 28 wrists median nerve CSA were less than the cut-off value, 17 wrists were missed by Dr. A, 26 wrists by Dr. B, and only 6 wrists were missed by radiomics model. A total of 335 radiomics features were extracted from each MN, of which 10 features were significantly different between compressed and normal nerves, and were used to construct the model. The area under curve (AUC) value, sensitivity, specificity, and accuracy of the radiomics model in the training set and testing set were 0.939, 86.17%, 87.10%, 86.63%, and 0.891, 87.50%, 80.49%, and 83.95%, respectively. The AUC value, sensitivity, specificity, and accuracy of the two doctors in the diagnosis of CTS were 0.746, 75.37%, 73.88%, 74.63% and 0.679, 68.66%, 67.16%, and 67.91%, respectively. The radiomics model was superior to the two-radiologist diagnosis, especially when there was no significant change in CSA.

CONCLUSION

Radiomics based on ultrasound images can quantitatively analyze the subtle changes in the median nerve, and can automatically and accurately diagnose CTS without measuring CSA, especially when there was no significant change in CSA, which was better than radiologists.

Prevalence of Carpal Tunnel Syndrome Symptoms Among Young Dentists

Objectives Although age is a risk factor, carpal tunnel syndrome (CTS) can also affect younger individuals, particularly those involved in activities or occupations that require repetitive hand movements, forceful gripping, or prolonged wrist flexion/extension. This case-control study aimed to examine the prevalence of CTS symptoms and frequent object dropping among a group of young dentists who are exposed to CTS risk factors. Additionally, other reported risk factors for CTS, such as sex, obesity, and square wrist sign, were also investigated. Methods A total of 74 dentists (48 women, mean age 28.5 years), who are working at Istanbul Faculty of Dentistry, the largest dental school in Istanbul, which is the biggest city in Turkey, were included in the study. Additionally, 61 age- and sex-matched controls (38 women, mean age 27.9 years) were also recruited. The Edinburgh Hand Preference Questionnaire, Boston Carpal Tunnel Syndrome Questionnaire (BCTQ), a questionnaire for object dropping and occupational hand usage, anthropometric measurements of the hands, clinical neurologic examination, and electromyography intended for the detection of CTS were performed. Results The dentists had a higher total weekly hand usage duration compared to the controls (66.3 vs 44.8 hours, p<0.001). BCTQ scores and the frequency of object dropping were also significantly higher in dentists compared to controls (respective p values: 0.011, 0.003). Positive correlations were found between BCTQ scores, hand usage durations, and object dropping (respective p values: 0.001, <0.001). BCTQ scores were higher in women than in men (p=0.027). Electrophysiologic evidence of CTS was found in one dentist. Conclusions Symptoms of CTS may manifest in individuals at a younger age than predicted, primarily influenced by their occupation and the duration of hand usage. Dentists, in particular, report a higher incidence of complaints related to object dropping, which can be attributed to their frequent use of specialized tools and engagement in delicate tasks, resulting in heightened awareness. However, it can also potentially serve as an indicator of CTS.

The Application of Ultrasound Image-Based Radiomics in the Diagnosis of Mild Carpal Tunnel Syndrome

OBJECTIVES

The ultrasound diagnosis of mild carpal tunnel syndrome (CTS) is challenging. Radiomics can identify image information that the human eye cannot recognize. The purpose of our study was to explore the value of ultrasound image-based radiomics in the diagnosis of mild CTS.

METHODS

This retrospective study included 126 wrists in the CTS group and 88 wrists in the control group. The radiomics features were extracted from the cross-sectional ultrasound images at the entrance of median nerve carpal tunnel, and the modeling was based on robust features. Two radiologists with different experiences diagnosed CTS according to two guidelines. The area under receiver (AUC) operating characteristic curve, sensitivity, specificity, and accuracy were used to evaluate the diagnostic efficacy of the two radiologists and the radiomics model.

RESULTS

According to guideline one, the AUC values of the two radiologists for CTS were 0.72 and 0.67, respectively; according to guideline two, the AUC were 0.73 and 0.68, respectively. The radiomics model achieved the best accuracy when 16 important robust features were selected. The AUC values of training set and test set were 0.92 and 0.90, respectively.

CONCLUSIONS

The radiomics label based on ultrasound images had excellent diagnostic efficacy for mild CTS. It is expected to help radiologists to identify early CTS patients as soon as possible, especially for inexperienced doctors.

Feasibility of artificial intelligence assisted quantitative muscle ultrasound in carpal tunnel syndrome

BACKGROUND

In case of focal neuropathy, the muscle fibers innervated by the corresponding nerves are replaced with fat or fibrous tissue due to denervation, which results in increased echo intensity (EI) on ultrasonography. EI analysis can be conducted quantitatively using gray scale analysis. Mean value of pixel brightness of muscle image defined as EI. However, the accuracy achieved by using this parameter alone to differentiate between normal and abnormal muscles is limited. Recently, attempts have been made to increase the accuracy using artificial intelligence (AI) in the analysis of muscle ultrasound images. CTS is the most common disease among focal neuropathy. In this study, we aimed to verify the utility of AI assisted quantitative analysis of muscle ultrasound in CTS.

METHODS

This is retrospective study that used data from adult who underwent ultrasonographic examination of hand muscles. The patient with CTS confirmed by electromyography and subjects without CTS were included. Ultrasound images of the unaffected hands of patients or subjects without CTS were used as controls. Ultrasonography was performed by one physician in same sonographic settings. Both conventional quantitative grayscale analysis and machine learning (ML) analysis were performed for comparison.

RESULTS

A total of 47 hands with CTS and 27 control hands were analyzed. On conventional quantitative analysis, mean EI ratio (i.e. mean thenar EI/mean hypothenar EI ratio) were significantly higher in the patient group than in the control group, and the AUC was 0.76 in ROC analysis. In the analysis using machine learning, the AUC was the highest for the linear support vector classifier (AUC = 0.86). When recursive feature elimination was applied to the classifier, the AUC value improved to 0.89.

CONCLUSION

This study showed a significant increase in diagnostic accuracy when AI was used for quantitative analysis of muscle ultrasonography. If an analysis protocol using machine learning can be established and mounted on an ultrasound machine, a noninvasive and non-time-consuming muscle ultrasound examination can be conducted as an ancillary tool for diagnosis.

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.

Peripheral Neuropathy in Systemic Autoimmune Rheumatic Diseases-Diagnosis and Treatment

Peripheral neuropathy (PN) is frequently observed in systemic rheumatic diseases and is a challenge in clinical practice. We aimed to review the evidence on the subject and proposed a comprehensive approach to these patients, facilitating diagnosis and management. We searched the MEDLINE database for the terms (and its respective Medical Subject Headings (MeSH) terms): "peripheral neuropathy" AND "rheumatic diseases" OR "systemic lupus erythematosus", "rheumatoid arthritis", "Sjogren syndrome", and "vasculitis" from 2000 to 2023. This literature review focuses on the diagnostic workup of PNs related to systemic lupus erythematosus, Sjögren's syndrome, rheumatoid arthritis, and systemic vasculitis. For every type of PN, we provide a pragmatic flowchart for diagnosis and also describe evidence-based strategies of treatment.

Ultrasound-based radiomics in the diagnosis of carpal tunnel syndrome: The influence of regions of interest delineation method on mode

BACKGROUND

In the recent years, artificial intelligence (AI) algorithms have been used to accurately diagnose musculoskeletal diseases. However, it is not known whether the particular regions of interest (ROI) delineation method would affect the performance of the AI algorithm.

PURPOSE

The purpose of this study was to investigate the influence of ROI delineation methods on model performance and observer consistency.

METHODS

In this retrospective analysis, ultrasound (US) measures of median nerves affected with carpal tunnel syndrome (CTS) were compared to median nerves in a control group without CTS. Two methods were used for delineation of the ROI: (1) the ROI along the hyperechoic medial edge of the median nerve but not including the epineurium (MN) (ROI1); and (2) the ROI including the hyperechoic epineurium (ROI2), respectively. The intra group correlation coefficient (ICC) was used to compare the observer consistency of ROI features (i.e. the corresponding radiomics parameters). Parameters α₁ and α₂ were obtained based on the ICC of ROI₁ features and ROI₂ features. The ROC analysis was used to determine the area under the curve (AUC) and evaluate the performance of the radiologists and network. In addition, four indices, namely sensitivity, specificity, positive prediction and negative prediction were analyzed too.

RESULTS

A total of 136 wrists of 77 CTS group and 136 wrists of 74 control group were included in the study. Control group was matched to CTS group according to the age and sex. The observer consistency of ROI features delineated by the two schemes was different, and the consistency of ROI₁ features was higher (α1 ˃ α2). The intra-observer consistency was higher than the inter-observer consistency regardless of the scheme, and the intra-observer consistency was higher when chose scheme one. The performances of models based on the two ROI features were different, although the AUC of each model was greater than 0.8.The model performed better when the MN epineurium was included in the ROI. Among five artificial intelligence algorithms, the Forest models (model₁ achieved an AUC of 0.921 in training datasets and 0.830 in testing datasets; model₂ achieved an AUC of 0.967 in training datasets and 0.872 in testing datasets.) obtained the highest performance, followed by the support vector machine (SVM) models and the Logistic models. The performances of the models were significantly better than the inexperienced radiologist (Dr. B. Z. achieved an AUC of 0.702).

CONCLUSION

Different ROI delineation methods may affect the performance of the model and the consistency of observers. Model performance was better when the ROI contained the MN epineurium, and observer consistency was higher when the ROI was delineated along the hyperechoic medial border of the MN.

Magnetic resonance imaging as a first-choice imaging modality in carpal tunnel syndrome: new evidence

BACKGROUND

Carpal tunnel syndrome (CTS) is the most common type of peripheral nerve compression. Magnetic resonance imaging (MRI) is becoming more popular in practice in the evaluation of CTS.

PURPOSE

To evaluate the diagnostic value of MRI in CTS.

MATERIAL AND METHODS

A cross-sectional study of 39 wrists was conducted. Clinical and nerve conduction study findings were evaluated and graded according to the Boston Carpal Tunnel Questionnaire (BCTQ) and the American Association of Neuromuscular and Electrodiagnostic Medicine. MRI was performed using a 1.5-T scanner. MRI parameters included cross-sectional area (CSA) of the median nerve and the ratio change in CSA at four levels: distal radioulnar joint (DRUJ-CSA); pisiform (p-CSA); middle of the carpal tunnel (i-CSA); and hook of hamate. The ratio change in CSA was expressed as p-CSA/DRUJ-CSA and ΔCSA (difference between iCSA and DRUJ-CSA), the flattening ratio of the median nerve, the thickness of the flexor retinaculum, flexor retinaculum bowing ratio, signal intensity ratio of the median, nerve and hypothenar muscle signal intensity.

RESULTS

With a cutoff point of 10.9 mm² of the p-CSA, MRI had a sensitivity and specificity of 97.4% and 80% for diagnosis of CTS, respectively. There was a significant association between the clinical and electrophysiological stage with MRI findings (P < 0.001). There was a positive correlation between the BCTQ score and MRI parameters (0.5 < r < 0.7, P < 0.01).

CONCLUSION

MRI has good diagnostic value in evaluating CTS. We recommend using p-CSA ≥10.9 mm² and ΔCSA ≥2.3 mm² as MRI diagnostic criteria of CTS.

Quantitative parameters of diffusion tensor imaging in the evaluation of carpal tunnel syndrome

BACKGROUND

To explore the value of diffusion tensor imaging (DTI)-derived metrics in quantitative evaluation of carpal tunnel syndrome (CTS).

METHODS

This prospective cross-sectional study included 39 wrists from 24 symptomatic CTS patients, who underwent clinical, electrophysiological, and magnetic resonance imaging (MRI) evaluations. In addition, 10 wrists of 6 healthy participants were included as controls. Clinical and nerve conduction study (NCS) findings were evaluated and graded according to the Boston Carpal Tunnel Questionnaire (BCTQ) and the American Association of Neuromuscular and Electrodiagnostic Medicine (AANEM), respectively. We performed MRI using a 1.5 Tesla scanner. Mean diffusivity (MD), fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD) of the median nerve at the distal radioulnar joint (DRUJ) (d), the inlet of the carpal tunnel (CT) at the pisiform level (i), the middle of the CT (m) and the outlet of the CT at the level of the hook of hamate (o), cross-sectional area at the inlet of the CT (iCSA), and the difference between MD and FA of the DRUJ and the outlet of CT (Delta MD and Delta FA) were measured.

RESULTS

The CTS patients had significantly lower FA [for example, oFA: mean difference 0.09, 95% confidence interval (CI): 0.05 to 0.12] and significantly higher MD than healthy participants (for example, iMD: mean difference 0.3, 95% CI: 0.03 to 0.57). There was a negative correlation between iCSA with iFA and between mFA and oFA (-0.5

CONCLUSIONS

The DTI-derived quantitative metrics add potential value to the evaluation of CTS. Alterations in the FA of the median nerve along the CT are the most significant features of CTS and reflect the degree of median nerve compression and clinical deficit. With a cutoff value of 0.45, FA at the carpal outlet has a sensitivity and specificity of 87.5% and 85.7% in the diagnosis of CTS, respectively.

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Key Words

• Boston Carpal Tunnel Questionnaire
• Carpal tunnel syndrome (CTS)
• apparent diffusion coefficient (ADC)
• diffusion tensor imaging (DTI)
• fraction anisotropy
• magnetic resonance imaging (MRI)
• nerve conduction study (NCS)

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MESH Headings Collapse

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Affiliation(s)

Nhu Quynh Vo Department of Radiology, University of Medicine and Pharmacy, Hue University, Hue, Vietnam
Ngoc Thanh Hoang Department of Radiology, University of Medicine and Pharmacy, Hue University, Hue, Vietnam
Duy Duan Nguyen Department of Internal Medicine, University of Medicine and Pharmacy, Hue University, Hue, Vietnam
Thi Hieu Dung Nguyen Department of Physiology, University of Medicine and Pharmacy, Hue University, Hue, Vietnam
Trong Binh Le Department of Radiology, University of Medicine and Pharmacy, Hue University, Hue, Vietnam
Nghi Thanh Nhan Le Department of Surgery, University of Medicine and Pharmacy, Hue University, Hue, Vietnam
Thanh Thao Nguyen Department of Radiology, University of Medicine and Pharmacy, Hue University, Hue, Vietnam

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Role of High Frequency Ultrasound in Diagnosing Carpal Tunnel Syndrome as Compared with Conventional Nerve Conduction Studies

Objective:

Our aim was to evaluate High Frequency Ultrasonography as a tool for diagnosis in patients withcarpal tunnel syndrome in comparison with electrophysiological study.

Methods:

Thirty- one patients [56 hands] with CTS and twenty-five asymptomatic controls [50 hands] were assessed and underwent ultrasonography of the wrists and electrophysiological testing. Data from the patient and the control groups was compared for both the investigations to determine the CTS and the grade of severity.

Results:

There was a high degree of correlation between the conduction abnormalities of the median nerve as detected by electrodiagnostic tests, historic and objective scale [Hi-Ob] and the measurement of the cross-sectional area of the nerve by US (P < 0.05). A cut-off point of 0.88 mm² for the mean cross-sectional area of the median nerve was found to be the upper limit for normal values. Compared to Ultrasonography which found one hand negative, six hands (10%) were negative on the electrophysiological tests. Using critical CSA value of 1.0 mm² in these CTS cases by US with sensitivity and specificity of 100% and 88%. Based on the results of this study, ultrasonography of wrist is another useful tool along with nerve conduction studies as per sensitivity and specificity patterns found in our study in diagnosis of carpal tunnel syndrome.

Conclusion:

High-frequency US examination of the median nerve and measurement of its cross-sectional area can be strongly considered as useful diagnostic diagnostic modality for the evaluation of CTS along with nerve conduction studies. In addition to its high diagnostic accuracy it is able to define the cause of nerve compression, aids treatment planning and provides a reliable method to follow response to therapy.

Accurate automated diagnosis of carpal tunnel syndrome using radiomics features with ultrasound images: A comparison with radiologists' assessment

PURPOSE

Ultrasonography is the most common imaging modality used to diagnose carpal tunnel syndrome (CTS). Recently artificial intelligence algorithms have been used to diagnose musculoskeletal diseases accurately without human errors using medical images. In this work, a computer-aided diagnosis (CAD) system is developed using radiomics features extracted from median nerves (MN) to diagnose CTS accurately.

METHOD

This study is performed on 228 wrists from 65 patients and 57 controls, with an equal number of control and CTS wrists. Nerve conduction study (NCS) is considered as the gold standard in this study. Two radiologists used two guides to evaluate and categorize the pattern and echogenicity of MNs. Radiomics features are extracted from B-mode ultrasound images (Ultrasomics), and the robust features are fed into support vector machine classifier for automated classification. The diagnostic performances of two radiologists and the CAD system are evaluated using ROC analysis.

RESULTS

The agreement of two radiologists was excellent for both guide 1 and 2. The honey-comb pattern clearly appeared in control wrists (based on guide 1). In addition, CTS wrists indicated significantly lower number of fascicles in MNs (based on guide 2). The area under ROC curve (AUC) of the radiologist 1 and 2 are 0.658 and 0.667 based on guide 1 and 0.736 and 0.721 based on guide 2, respectively. The CAD system indicated higher performance than two radiologists with AUC of 0.926.

CONCLUSION

The proposed CAD system shows the benefit of using ultrasomics features and can assist radiologists to diagnose CTS accurately.

Clinico-radiological review of peripheral entrapment neuropathies - Part 1 upper limb

PURPOSE

This article aims to review the pertinent anatomy, etiopathogenesis, current clinical and radiological concepts and principles of management in case of upper limb entrapment neuropathies.

METHODS

The review is based on critical analysis of the existing literature as well as our experience in dealing with entrapment neuropathies.

RESULTS

Entrapment neuropathies of the upper limb peripheral nerves are common conditions that are often misdiagnosed because of their varying clinical presentations and lack of standardized diagnostic methods. Clinical assessment and electrodiagnostic studies have been the mainstay; however, imaging techniques have provided newer insights into the pathophysiology of these entities, leading to a paradigm shift in their diagnosis and management. The current best practice protocols for entrapment syndromes are constantly evolving with increasing emphasis on the role high-resolution ultrasound and magnetic resonance imaging. Many imaging criteria are described and we have tried to present the most validated measurements for diagnosing entrapment neuropathies.

CONCLUSION

It is imperative for a clinical radiologist to be familiar with the etiopathogenesis and clinical features of these conditions, in addition to being thorough with the anatomy and the latest imaging strategies.

Psychosocial Risk Factors and the Association With Carpal Tunnel Syndrome: A Systematic Review

BACKGROUND

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy of the upper limb. Research has shown that associative factors for CTS include occupational and biomechanical elements, sex, and age. To date, no systematic review has been undertaken to determine specifically whether there are any psychosocial risk factors in developing CTS. The objective is to determine whether psychosocial factors are associated with and/or predict the development of CTS.

METHODS

A systematic review was conducted including searches of PubMed (MEDLINE), EMBASE, and CINAHL from inception to May 30, 2017. Quantitative studies must have investigated a minimum of 1 or more psychosocial factors-cognitive, affective, behavioral, vocational, or interpersonal processes (eg, social support)-and include a point or risk estimate. One reviewer conducted the search and 2 reviewers independently assessed eligibility and completed methodological quality assessment using a modified Downs and Black checklist. Data were analyzed narratively.

RESULTS

Six moderate- to high-quality studies were included in the final review. Five studies reported a positive association between psychosocial factors and CTS, where psychosocial factors were more in those who reported CTS. One study reported no positive or negative association with CTS development. Four studies reported a negative association between psychosocial factors and CTS, where psychosocial factors were less in those who reported CTS.

CONCLUSIONS

There is limited evidence for a positive association between psychosocial factors and CTS. However, this was not a consistent finding across all included studies. Further research is indicated in standardizing CTS diagnostic criteria and investigating other working environments.

Blood Flow Changes in Subsynovial Connective Tissue on Contrast-Enhanced Ultrasonography in Patients With Carpal Tunnel Syndrome Before and After Surgical Decompression

OBJECTIVES

Although qualitative alteration of the subsynovial connective tissue in the carpal tunnel is considered to be one of the most important factors in the pathophysiologic mechanisms of carpal tunnel syndrome (CTS), little information is available about the microcirculation in the subsynovial connective tissue in patients with CTS. The aims of this study were to use contrast-enhanced ultrasonography (US) to evaluate blood flow in the subsynovial connective tissue proximal to the carpal tunnel in patients with CTS before and after carpal tunnel release.

METHODS

The study included 15 volunteers and 12 patients with CTS. The blood flow in the subsynovial connective tissue and the median nerve was evaluated preoperatively and at 1, 2, and 3 months postoperatively using contrast-enhanced US.

RESULTS

The blood flow in the subsynovial connective tissue was higher in the patients with CTS than in the volunteers. In the patients with CTS, there was a significant correlation between the blood flow in the subsynovial connective tissue and the median nerve (P = .01). The blood flow in both the subsynovial connective tissue and the median nerve increased markedly after carpal tunnel release.

CONCLUSIONS

Our results suggest that increased blood flow in the subsynovial connective tissue may play a role in the alteration of the microcirculation within the median nerve related to the pathophysiologic mechanisms of CTS. The increase in the blood flow in the subsynovial connective tissue during the early postoperative period may contribute to the changes in intraneural circulation, and these changes may lead to neural recovery.

Are the Sensory Fibers of the Ulnar Nerve Affected in Carpal Tunnel Syndrome?

PURPOSE

Distribution of paresthesia throughout the skin area without median nerve innervation is frequently seen in carpal tunnel syndrome (CTS). However, its pathophysiologic mechanisms are still unclear. We aimed to research whether a dysfunction in sensory fibers of the ulnar nerve (UN) was present or not in hands with CTS.

METHODS

Totally, upper extremity nerve conduction study recordings of 508 patients were considered. After exclusions, 331 upper extremity recordings of 277 patients were included. We compared the results of sensory conduction studies of median nerve and UN between normal hands and hands with CTS.

RESULTS

The mean distal sensory latency of the median nerve was longer, the mean conduction velocity was slower, and mean nerve action potential amplitude was higher in the hands with CTS than in normal hands (P < 0.001 for all comparisons). There was no statistically significant difference on any sensory conduction parameters of UN recorded on digit IV or digit V between the disease and control groups (P > 0.05 for all comparisons). The rates of conduction abnormalities of the UN sensory fibers were also similar in hands with CTS and in normal hands (P > 0.05 for all comparisons).

CONCLUSIONS

The hands with CTS do not have an increased rate of conduction abnormalities of UN sensory fibers compared with the normal hands in our study population. Therefore, our study did not confirm the distortion of UN sensory fibers as a mechanism underlying the spread of paresthesia throughout the skin area without median nerve innervation in CTS.

Overall health status in patients with mild to moderate carpal tunnel syndrome: A case-control study

STUDY DESIGN

A case-control study.

INTRODUCTION

There are no reports in the literature that evaluate the overall health status (OHS) of patients with mild to moderate forms of carpal tunnel syndrome (CTS) using 36-Item Short Form Health Survey (SF-36).

PURPOSE OF THE STUDY

To assess OHS in patients with mild to moderate CTS, in comparison with healthy subjects.

METHODS

The study involved 273 healthy people and 140 people diagnosed with CTS. The CTS diagnosis was made on the basis of clinical examinations and nerve conduction studies. OHS was assessed using the SF-36.

RESULTS

In the assessment of physical components of OHS, in the CTS group (compared with healthy subjects), the results show significantly lower values in physical functioning, role limitations because of physical health problems, bodily pain, and general health perceptions by 7.44, 23.2, 18.9, and 4.1, respectively. Mental components were lower (in CTS group) only in relation to vitality and social functioning by 4.1 and 5.5, respectively. In the assessment of physical component summary (PCS) and mental component summary (MCS), the results show significantly lower values of PCS (by 13 in CTS group) and no significant differences in the assessment of MCS between patients with CTS and healthy subjects.

DISCUSSION

The perception of the OHS in CTS patients is diminished. Hence, when evaluating the effects of the therapy, not only disease-specific scales should be used, but also the OHS. This will allow an assessment of the impact of CTS on OHS and the impact of applied therapy, not only in terms of a reduction in the main symptoms of the condition.

CONCLUSIONS

Mild and moderate forms of CTS significantly affected the PCS of the OHS and all its subcomponents (physical functioning, role limitations because of physical health problems, bodily pain, and general health perceptions) but did not affect the MCS of OHS evaluated as a whole. There were significant differences in the mental component in the evaluation of vitality and social functioning.

LEVEL OF EVIDENCE

3.

Longitudinal Outcomes Following a Randomized Controlled Trial of Dynamic Splint Stretching for Carpal Tunnel Syndrome

Background: The incidence of carpal tunnel syndrome (CTS) is 48 million patients in the United States. The purpose of this longitudinal study was to determine whether Dynasplint stretching (immediately after diagnosis) had an effect on a patient's decision to seek surgical treatment for CTS. Methods: Fifty patients (10 men, 40 women, mean age 51.2 ± 12 years) were recruited for this randomized, controlled, longitudinal trial. Patients were diagnosed with CTS by physical examination and nerve conduction studies. The intervention used was Dynasplint stretching that delivered a prolonged duration of low load stretching. Patients who were randomly chosen for the Experimental category wore the device for two 30-minute sessions per day with regular increases in splint tension for 60 days. Control patients received nonsteroidal anti-inflammatory medication plus instructions on daily home stretching. Results: The final, longitudinal outcome showed a 72% reduction in surgery chosen by the experimental group (n = 25), compared with 38% reduction for control patients (n = 25). Conclusions: Immediate treatment with Dynasplint stretching showed a 2 to 1 reduction in surgery, with abundant financial savings.

The evaluation of vitamin D levels in patients with carpal tunnel syndrome

The aim of this study was to evaluate the relationship between 25-hydroxyvitamin D (25(OH)D) levels and carpal tunnel syndrome (CTS). 25(OH)D levels were checked in 108 consecutive patients with CTS symptoms and 52 healthy controls. All patients underwent nerve conduction studies and completed Boston Carpal Tunnel Questionnaire (BQ) symptom severity and functional status scales to quantify symptom severity, pain status and functional status. There were 57 patients with electrophysiological confirmed CTS (EP+ group) and 51 electrophysiological negative symptomatic patients (EP- group). 25(OH) D deficiency (25(OH)D < 20 ng/ml) was found in 96.1 % of EP- group, in 94.7 % of EP+ group and in 73.8 % of control group. 25(0H) D level was found significantly lower both in EP+ and EP- groups compared to control group (p = 0.006, p < 0.001, respectively). Although mean vitamin D level in EP- group was lower than EP+ group, statistically difference was not significant between EP+ and EP- groups (p = 0.182). BQ symptom severity and functional status scores and BQ pain sum score were not significantly different between EP+ and EP- groups. We found no correlation with 25(OH) D level for BQ symptom severity, functional status and pain sum scores. 25(OH) D deficiency is a common problem in patients with CTS symptoms. As evidenced by the present study, assessment of serum 25(OH)D is recommended in CTS patients even with electrophysiological negative results.

Value of F-wave studies on the electrodiagnosis of carpal tunnel syndrome

BACKGROUND

F waves are late electrophysiological responses to antidromic activation of motor neurons and are used to evaluate the conduction along the whole length of peripheral nerves. We aimed to determine the diagnostic efficacies of minimum median nerve F-wave latency (FWL) and median-to-ulnar nerve F-wave latency difference (FWLD) on carpal tunnel syndrome (CTS).

MATERIALS AND METHODS

The electrophysiological studies consisted of sensory and motor nerve conduction and F-wave studies of the median and ulnar nerves. The best cut-off points of minimum median nerve FWL and FWLD for the diagnosis of CTS were detected for the whole study group and for different height subgroups (Group 1: 150-159 cm, Group 2: 160-169 cm, and Group 3: over 170 cm). The diagnostic efficacies of minimum median nerve FWL and FWLD were calculated for the whole CTS group and for the mild CTS group, separately.

RESULTS

The best cut-off point of minimum median nerve FWL on the diagnosis of CTS was determined as 24.60 ms for the whole group. It was 23.90 ms for Group 1, 24.80 ms for Group 2, and 28.40 ms for Group 3. The usage of these stratified cut-off points yielded a higher total diagnostic efficacy rate than single cut-off point usage (79.9% vs 69%, respectively; P=0.02). The best cut-off point of FWLD on the diagnosis of CTS was 0.80 ms for the whole group. It was 0.55 ms for Group 1, 0.30 ms for Group 2, and 0.85 ms for Group 3. Both the single cutoff point usage and the stratified chart usage for FWLD had equal diagnostic efficacy (85.1%). In the mild CTS group, diagnostic efficacy was 55.5% for minimum median nerve FWL and 78.8% for FWLD (P=0.0001).

CONCLUSION

Median-to-ulnar nerve FWLD yields a higher diagnostic efficacy than minimum median nerve FWL on the diagnosis of CTS. However, the sensitivities of both parameters are not satisfactory for the extremities with mild CTS, which compose the main group having diagnostic challenge.

Does measuring the median nerve at the carpal tunnel outlet improve ultrasound CTS diagnosis?

INTRODUCTION

Nerve conduction is often regarded as more sensitive than ultrasonography (US) for diagnosing carpal tunnel syndrome (CTS). The diagnostic value of US derives from median nerve enlargement occurring at both ends of the carpal tunnel resulting in a dumbbell-like swelling from carpal tunnel pressure. An important reason for the inferior sensitivity of US may be because measurements are restricted to the carpal tunnel inlet. We investigate the value of including median nerve enlargement at the carpal tunnel outlet for diagnosing CTS.

METHODS

Retrospective cohort study of nerve conduction verified CTS, determining sensitivity, specificity, and positive and negative predictive values of carpal tunnel inlet and outlet median nerve cross sectional area as determined by US for the diagnosis of CTS. Nerve conduction graded CTS severity.

RESULTS

127 hands from 77 patients with CTS and 35 control healthy hands were assessed. US sensitivity for diagnosing CTS increased from 65% to 84% by including outlet enlargement of the median nerve. Specificity changed from 94% to 86%, positive predictive value from 98% to 96% and the negative predictive value from 43% to 60%. 25 hands out of the 127 from CTS patients showed enlargement restricted to the outlet and mainly occurred in moderate CTS.

CONCLUSION

In our population, the use of carpal tunnel outlet median nerve enlargement in addition to inlet median nerve size increases sensitivity for diagnosing CTS by 19%.

Outcomes and cost-effectiveness of carpal tunnel injections using sonographic needle guidance

This randomized controlled study addressed whether sonographic needle guidance affected the outcomes of corticosteroid injection for symptomatic carpal tunnel syndrome. Seventy-seven symptomatic carpal tunnels were randomized to injection by either (1) conventional anatomic landmark palpation-guided injection or (2) sonographic image-guided injection, each using a two-step technique where 3 ml of 1% lidocaine was first injected to hydrodissect and hydrodisplace critical intra-carpal tunnel structures followed by injection with 80 mg of triamcinolone acetonide (2 ml). Baseline pain, procedural pain, pain at outcome (2 weeks and 6 months), responders, therapeutic duration, total cost, and cost per responder were determined. There were no complications in either treatment group. Relative to conventional anatomic landmark palpation-guided methods, sonographic guidance for injection of the carpal tunnel resulted in 77.1% reduction in injection pain (p<0.01), a 63.3% reduction in pain scores at outcome (p<0.014), 93.5% increase in the responder rate (p<0.001), 84.6% reduction in the non-responder rate (p<0.001), a 71.0% increase in therapeutic duration (p<0.001), and a 59.3% ($150) reduction in cost/responder/year for a hospital outpatient (p<0.001). However, despite improved outcomes, cost per patient per year was significantly increased for an outpatient in a physician's office and was neutral for a hospital outpatient. Sonographic needle guidance significantly improves the performance and clinical outcomes of injection of the carpal tunnel and is cost-effective for a hospital-based practice, but based on current reimbursements, it significantly increases overall costs for medical care delivered in a non-hospital-based physician practice.

Symptoms, signs and nerve conduction velocities in patients with suspected carpal tunnel syndrome

BACKGROUND

To inform the clinical management of patients with suspected carpal tunnel syndrome (CTS) and case definition for CTS in epidemiological research, we explored the relation of symptoms and signs to sensory nerve conduction (SNC) measurements.

METHODS

Patients aged 20-64 years who were referred to a neurophysiology service for investigation of suspected CTS, completed a symptom questionnaire (including hand diagrams) and physical examination (including Tinel's and Phalen's tests). Differences in SNC velocity between the little and index finger were compared according to the anatomical distribution of symptoms in the hand and findings on physical examination.

RESULTS

Analysis was based on 1806 hands in 908 patients (response rate 73%). In hands with numbness or tingling but negative on both Tinel's and Phalen's tests, the mean difference in SNC velocities was no higher than in hands with no numbness or tingling. The largest differences in SNC velocities occurred in hands with extensive numbness or tingling in the median nerve sensory distribution and both Tinel's and Phalen's tests positive (mean 13.8, 95% confidence interval (CI) 12.6-15.0 m/s). Hand pain and thumb weakness were unrelated to SNC velocity.

CONCLUSIONS

Our findings suggest that in the absence of other objective evidence of median nerve dysfunction, there is little value in referring patients of working age with suspected CTS for nerve conduction studies if they are negative on both Tinel's and Phalen's tests. Alternative case definitions for CTS in epidemiological research are proposed according to the extent of diagnostic information available and the relative importance of sensitivity and specificity.

High-resolution sonography detects extraforaminal nerve pathology in patients initially diagnosed with cervical disc disease: a case series

In patients presenting with neck and upper limb complaints, MRI changes suggestive of cervical disc disease do not exclude concomitant extraforaminal pathology, as shown in the series of three cases presented here. High-resolution ultrasound of the brachial plexus and peripheral nerves may be useful in identifying an extraforaminal pathology when (1) symptoms and signs are disproportionate to MRI findings of cervical disc disease; (2) there is obvious discordance between MRI and nerve conduction findings; (3) an entrapment neuropathy is suspected but the site of nerve lesion is unidentifiable on the basis of available investigations and clinical findings.

Ultrasound for diagnosis of carpal tunnel syndrome: comparison of different methods to determine median nerve volume and value of power Doppler sonography

OBJECTIVE

To compare ultrasound measurement of median nerve cross-sectional area (CSA) at different anatomical landmarks and to assess the value of power Doppler signals within the median nerve for diagnosis of carpal tunnel syndrome (CTS).

METHODS

A prospective study of 135 consecutive patients with suspected CTS undergoing two visits within 3 months. A final diagnosis of CTS was established by clinical and electrophysiological findings. CSA was sonographically measured at five different levels at forearm and wrist; and CSA wrist to forearm ratios or differences were calculated. Intraneural power Doppler signals were semiquantitatively graded. Diagnostic values of different ultrasound methods were compared by receiver operating characteristic curves using SPSS.

RESULTS

CTS was diagnosed in 111 (45.5%) wrists; 84 (34.4%) had no CTS and 49 (20.1%) were possible CTS cases. Diagnostic values were comparable for all sonographic methods to determine median nerve swelling, with area under the curves ranging from 0.75 to 0.85. Thresholds of 9.8 and 13.8 mm(2) for the largest CSA of the median nerve yielded a sensitivity of 92% and a specificity of 92%. A power Doppler score of 2 or greater had a specificity of 90% for the diagnosis of CTS. Sonographic median nerve volumetry revealed a good reliability with an intraclass correlation coefficient of 0.90 (95% CI 0.79 to 0.95).

CONCLUSIONS

Sonographic assessment of median nerve swelling and vascularity allows for a reliable diagnosis of CTS. Determination of CSA at its maximal shape offers an easily reproducible tool for CTS classification in daily clinical practice.

Provocation tests in doppler ultrasonography for carpal tunnel syndrome

INTRODUCTION

Doppler ultrasonography (DU) has recently been shown to be useful in imaging carpal tunnel syndrome (CTS). In this study, we aim to characterize the changes seen after exercise and electrical stimulation.

METHODS

Five patients with CTS were recruited with 5 age-matched subjects. DU was used to visualize the median nerve, flexor tendon, and bone at base line and after 1 minute of: (a) median nerve motor stimulation, (b) median nerve sensory stimulation, (c) abductor pollicis brevis contraction, and (d) adductor digiti minimi contraction.

RESULTS

Blood flow in the median nerve was greater after APB exercise. Furthermore, blood flow in the median nerve was greater in cases than controls after APB exercise. At baseline, blood flow in the flexor tendon was greater in cases than controls.

CONCLUSIONS

While limited by sample size, this study demonstrates that exercise of median innervated muscles may be useful in enhancing diagnostic utility of DU for CTS.

Gp Diagnostics and Splint Treatment of Carpal Tunnel Syndrome and Trapeziometacarpal Arthritis

Carpal tunnel syndrome (CTS) and trapeziometacarpal joint osteoarthritis (TMCJ OA) are common problems in the UK. Given the current financial climate, it is particularly important to improve cost effectiveness and avoid unnecessary patient referrals to the more expensive secondary care services. This could be achieved by initial management of these conditions in the primary care setting. For this to be possible, GPs must be able to make a reliable clinical diagnosis for these conditions. To our knowledge there are no studies that evaluate the reliability of GPs when making clinical diagnoses of CTS and TMCJ OA.

Hand-held nerve conduction device in carpal tunnel syndrome: a prospective study

INTRODUCTION

We assessed the clinical impact of replacing standard neurophysiologic testing with a hand-held device (Mediracer) for diagnosis of carpal tunnel syndrome (CTS).

METHODS

One hundred patients (200 hands) with suspected CTS were studied by blinded assessors [Hand-therapist (HT)1 and Consultant Neurophysiologist] using the Mediracer, followed by standard neurophysiologic testing. To simulate testing by personnel without neurological training, Mediracer recordings were analyzed separately by an assessor who had not seen the patients (HT2).

RESULTS

Correlation of the CTS grades was 0.94 for the results obtained by HT1, and 0.87 for HT2. The sensitivity and specificity of the Mediracer was 0.85 and 0.9, respectively, by HT1, and 0.84 and 0.89 for HT2. Nine patients had conditions other than CTS, and 35 patients were judged to require further investigation.

CONCLUSIONS

The Mediracer should only be used in patients with typical CTS symptoms and signs and no muscle wasting who have had careful neurological assessment.

Outcome prediction value of nerve conduction studies for endoscopic carpal tunnel surgery

OBJECTIVE

Carpal tunnel syndrome is the most common entrapment neuropathy. We explore the clinical use of nerve conduction study in the outcome prediction and preoperative selection for endoscopic carpal tunnel syndrome surgery.

METHODS

Sixty-seven patients with carpal tunnel syndrome were prospectively enrolled. Each patient's clinical symptomatic score at baseline and 3 months postsurgery was compared with nerve conduction study parameters of distal motor latency, motor amplitude, motor conduction velocity, distal sensory latency, sensory amplitude, and sensory conduction velocity. A statistical logistic regression model was used to ascertain outcomes.

RESULTS

Endoscopic surgery resulted in significant improvement for all four major symptoms pain, numbness, paresthesia, and weakness. From multivariate logistic regression, a shorter distal sensory latency is associated with a higher likelihood of a good outcome (P = 0.058; odds ratio, 0.912; 95% confidence interval, 0.828-1.0) only for paresthesia. The other factors were not found to be significant (all P > 0.10). The area under the curve (AUC) was 0.69 (95% confidence interval for AUC, 0.50-0.88). A cutoff of 6.0 ms or lower for sensory latency predicts for good outcome (in terms of paresthesia score) with the sensitivity/certainty of 84.6% and positive predictive value of 86.8%. A receiver operating characteristic analysis of baseline paresthesia score for good outcome of the paraesthesia domain showed that the AUC was 0.967 (95% confidence interval for AUC, 0-1.0). At a cutoff of baseline paraesthesia score of 4 or above, prediction for good outcome achieved a sensitivity of 87.2% and positive predictive value of 97.1%.

CONCLUSIONS

A shorter distal sensory latency is associated with a higher likelihood of a good outcome for paraesthesia. In addition, patients with baseline of 4 or above had correlated with better surgical outcome than those with less severe symptoms. Our data thus suggest that surgical benefit is best seen in patients with moderate symptoms, in combination with electrophysiological evidence of early demyelination, as a possible therapeutic window.

Correlation between the severity of carpal tunnel syndrome and color Doppler sonography findings

OBJECTIVE

Carpal tunnel syndrome (CTS) represents one of the most prevalent peripheral entrapment mononeuropathies. The purpose of our study was to assess the potential correlation between intraneural hypervascularization, flexor retinaculum bowing, and median nerve cross-sectional area and the severity of CTS in cases confirmed by nerve conduction study.

SUBJECTS AND METHODS

Sixty consecutive patients with classic or probable symptoms of CTS were enrolled in the study. A control group consisting of 27 healthy volunteers who were never diagnosed with CTS or had any symptoms of CTS was recruited among institution employees. All symptomatic patients were initially examined by a hand surgeon and subsequently referred for sonographic and electrophysiologic examinations.

RESULTS

A total of 90 wrists (in 60 patients) were included in the study. Twenty-eight (31.1%) had mild CTS, 33 had moderate disease, and 29 had severe disease. We detected significant correlation between median nerve hypervascularization and the severity of CTS (p = 0.01, logistic regression) for moderate CTS and (p = 0.04) for severe disease. We also detected a significant correlation in flexor retinaculum bowing and median nerve cross-sectional area with increase in the severity of CTS (p < 0.001 and < 0.008; chi-square test and analysis of variance, respectively).

CONCLUSION

Our study suggests that the severity of CTS strongly correlates with color Doppler sonography findings, and this technique may represent a reliable complementary tool in CTS examination.

Combined Doppler and B-mode sonography in carpal tunnel syndrome

An intraoperatively enlarged engorged median nerve has been described as typical of patients with carpal tunnel syndrome (CTS). Although many studies of CTS have addressed median nerve enlargement, little is known about the usefulness of Doppler methods in detecting median nerve engorgement combined with nerve cross-sectional area (CSA). In a retrospective study of hands referred for evaluation of possible CTS, patients were clinically graded into Highly-likely or Indeterminate CTS. Nerve conduction studies (NCS), CSA, and Doppler analysis were compared. Median nerve blood flow was detected in 29 of 30 Highly-likely CTS hands (mean 13.3m/s (8.2) SD) and in 25 of 30 with Indeterminate CTS (mean 8.5m/s (4.5) SD). These were significantly higher than our laboratory normal values (mean 1.9 m/s (2.8) SD). Raised intraneural blood flow showed the highest test sensitivity in diagnosing Highly-likely carpal tunnel syndrome (83%) and combined with CSA reached 90%. NCS sensitivity was 83%. In the group of Indeterminate CTS, combined blood flow and CSA showed abnormality in 77% and NCS 47%. All nerve conduction parameters and median nerve cross sectional area showed linear correlation to intraneural blood flow velocity (P<0.05; Spearman's r=0.362 to 0.264). This study suggests that adding measures of intraneural blood flow to CSA further improves the sonographic evaluation of CTS and may be of particular use in patients with negative NCS.

Sonographically guided hydrodissection and corticosteroid injection for scleroderma hand

Scleroderma is associated with intractable hand pain from vasospasm, digital ischemia, tenosynovitis, and nerve entrapment. This study investigated the effect of hydrodissection of the carpal tunnel followed by corticosteroid injection for the painful scleroderma hand. Twenty-six consecutive subjects [12 with painful scleroderma hand and 14 with rheumatoid arthritis and carpal tunnel syndrome (RA/CTS)] underwent sonographically observed carpal tunnel hydrodissection with 3 ml of 1% lidocaine administered with a 25-gauge 1-in. needle on a 3-ml RPD mechanical syringe (reciprocating procedure device). After hydrodissection, a syringe exchange was performed, and 80 mg of triamcinolone acetonide was injected. Baseline pain, procedural pain, pain at outcome, responders, therapeutic duration, and reinjection interval were determined. Hydrodissection and injection with corticosteroid significantly reduced pain scores by 67% in scleroderma (p < 0.001) and by 47% in RA/CT (p < 0.001). Scleroderma and RA/CTS were similar in outcome measures: injection pain (p = 0.47), pain scores at outcome (p = 0.13), responders (scleroderma, 83.3%; RA/CTS, 57.1%, p = 0.15), pain at 6 months (p = 0.15), and therapeutic duration (p = 0.07). Scleroderma patients responded better in time to next injection (scleroderma, 8.5 ± 3.0 months; RA/CTS, 5.2 ± 3.1 months, p = 0.03). Reduced Raynaud's attacks and healing of digital ulcers occurred in 83% of subjects. There were no complications. Hydrodissection with lidocaine followed by injection of triamcinolone reduces pain and vasomotor changes in the scleroderma hand. The mechanism may be a combination of hydrodissection-mediated mechanical freeing of entrapped arteries, nerves, and tendinous structures and corticosteroid-induced reduction of inflammatory vasospasm.

Effect of age on subjective complaints and objective severity of carpal tunnel syndrome: prospective study

OBJECTIVES

Older patients with carpal tunnel syndrome who are resistant to conservative treatment often have a less than satisfactory outcome after surgery. We therefore investigated whether the age of the patient affects the subjective complaints or the objective severity of the nerve entrapment prior to surgery in patients younger than 40 years compared with those above 70 years of age.

DESIGN

Prospective study.

SETTING

NHS specialist neurophysiology department.

PARTICIPANTS

One hundred and six splint-resistant patients scored their subjective complaints and scores were then compared with the neurophysiology results.

MAIN OUTCOME MEASURES

Nerve conduction speeds and subjective visual analogue score of pain, sensation and motor function.

RESULTS

Conduction speeds were significantly more affected in patients over 70 years of age than in those under 40 years. Older patients scored their subjective complaints lower than younger patients.

CONCLUSIONS

Older patients' subjective complaints misrepresent the severity of the nerve entrapment. Clinicians should have a lower threshold for objective investigation of patients older than 70 years of age to minimize development of irreversible nerve damage.

Median nerve small- and large-fiber damage in carpal tunnel syndrome: a quantitative sensory testing study

We explored the contribution of median nerve small (Aδ, C)-and large (Aβ)-fiber damage to the severity and topographic distribution of sensory symptoms in carpal tunnel syndrome (CTS) and the timing of fiber damage across CTS stages. We recruited 106 CTS patients. After selection, 49 patients were included. They underwent electrodiagnostic and quantitative sensory testing (QST) study and were asked on the severity of Boston Carpal Tunnel Questionnaire (BCTQ) Symptoms Severity Scale, daytime pain (DP), night pain and paresthesia, on the distribution of hand symptoms, and the presence of proximal symptoms. BCTQ Symptoms Severity Scale and DP severity was significantly correlated with Aδ-fiber damage. Small-fiber QST measures were impaired in electrodiagnostic-negative CTS patients and did not change across CTS neurographic stages. QST findings were not correlated to the topographical distribution of symptoms. Aδ-fiber damage contributes to CTS symptoms and in particular to DP. Night pain and paresthesia might be ascribed to ectopic fiber discharges secondary to median nerve enhanced mechanosensitivity. Small-fiber damage takes place earlier than large fiber. Median nerve fiber involvement does not directly contribute to extraterritorial symptoms spread. Our data may help understanding CTS pathophysiology and explain the well-known discrepancy between CTS symptoms and electrodiagnostic findings.

PERSPECTIVE

We explored the involvement of median nerve small and large fibers in carpal tunnel syndrome (CTS). We found a significant correlation between Aδ-fiber function and CTS symptoms. Small-fiber involvement took place in milder disease stages. These findings could help reconcile the discrepancy between CTS symptoms and electrodiagnostic data.

Sonography versus nerve conduction studies in patients referred with a clinical diagnosis of carpal tunnel syndrome

PURPOSE

To compare the diagnostic value of high-resolution ultrasound (US) with nerve conduction studies (NCS) in patients with clinically defined carpal tunnel syndrome (CTS).

METHODS

A prospective study was conducted on 66 consecutive patients investigated for sensory hand symptoms. The gold standard was the clinical diagnosis of CTS.

RESULTS

NCS showed greater diagnostic sensitivity (82%) than US (62%) in supporting a diagnosis of CTS. With increasing neurophysiologic severity of median neuropathy, there was increasing convergence of the two test methods. Abnormal US as the only diagnostic supportive evidence of CTS was rare. However, the positive predictive value of US for CTS was 100%.

CONCLUSION

NCS show better sensitivity than US in supporting a diagnosis of CTS. However, because of its high positive predictive value, one may consider using US as a screening test, eliminating the need for NCS in the majority of clinical suspicion of CTS and reserving NCS for cases in which US is negative.

Effects of perineural steroid injections on median nerve conduction during the carpal tunnel release

Background/Aim. The treatment outcome of the median nerve compressive neuropathy in the carpal zone due to carpal tunnel syndrome (CTS) is represented by recovering the nerves sensibility, conductivity, condition and strength. Perineural application of betamethasone during the surgical decompression might result in faster recovery of compressed median nerve's conduction speed. Methods. In this study 40 patients with CTS were randomly divided in the two groups. In the first group (n = 20) we performed the surgical decompression of the median nerve by the open release of the carpal tunnel, and in the second group (n = 20) we applicated a perineural injection of 1 ml of betamethason immediately after the surgical decompression. We performed the electrodiagnostic (ED) examinations 7, 30 and 90 days after the surgery, and measured the conduction speed of the median nerve in the carpal tunnel zone and the sensitivity conduction speed of the median nerve. Results. Significant differences in examined ED respective variable values in different time intervals were obtained. At the final measurements, 90 days after the surgical procedure, both groups evidenced a full recovery of the conduction speed in the carpal tunnel with statistically significant better results in the second group of the patients (t = -2.116; p = 0.043). Conclusion. Intraoperative application of the corticosteroid injection during the surgical decompression results in faster regaining of conduction speed of the median nerve.

Medial thenar recording in normal subjects and carpal tunnel syndrome

OBJECTIVE

Since little is known about the involvement of median nerve fibres to the medial thenar eminence in CTS, we determine the consistency of a motor response derived from a medial thenar motor (MTM) site. We then compare sensitivity and specificity of this novel site with other nerve conduction parameters in supporting a diagnosis of CTS.

METHODS

The motor responses over the MTM with ulnar and median stimulation were determined in healthy subjects and patients with CTS. Sensitivity and specificity of 4 motor techniques (Abductor Pollicis Brevis (APB) and median MTM latency, 2nd Lumbricales to Interossei latency difference (2-LINT), APB to Adductor Digiti Minimi (ADM) latency difference, median MTM to ulnar MTM latency difference) and the median sensory distal latency in confirming CTS were calculated using the ROC method.

RESULTS

132 hands (68 CTS, 64 controls) were examined. All but one median and ulnar nerve stimulation (both in patients with CTS) resulted in negative MTM compound muscle action potentials. Sensitivity and specificity in diagnosing CTS were 79/97% (APB) 90/98% (median MTM latency), 88/97% (2-LINT), 85/97% (APB to ADM latency difference) and 75/95% (median MTM to ulnar MTM latency difference). Median sensory latency showed 89% sensitivity and 97% specificity.

CONCLUSIONS

Median and ulnar stimulation results in consistent motor responses at the medial thenar site. Median distal motor latency to MTM is frequently abnormal in CTS showing similar sensitivity and specificity to 2-LINT and median distal sensory latency.

SIGNIFICANCE

The MTM site shows consistent responses to both median and ulnar stimulation. MTM distal latency can be considered a useful site for supporting a diagnosis of CTS.

Carpal tunnel syndrome--a comprehensive review

PURPOSE

To provide a comprehensive review of the management of carpal tunnel syndrome.

METHODS AND RESULTS

A systematic literature review is provided of the history, anatomy, pathophysiology, epidemiology, diagnostic criteria, investigative surgical techniques, results and complications for carpal tunnel syndrome.

CONCLUSION

Surgery for carpal tunnel syndrome requires meticulous attention to history-taking, investigation, counseling, training and surgical technique if unsatisfactory results and complications are to be avoided.