Longitudinal design for sonographic measurement of median nerve swelling with controlled exposure to physical work using an animal model

Evaluation of ultrasound as diagnostic tool in patients with clinical features suggestive of carpal tunnel syndrome in comparison to nerve conduction studies: Study protocol for a diagnostic testing study

BACKGROUND

Carpal Tunnel Syndrome (CTS) is the most common compressive neuropathy, accounting for 90% of all neuropathies. Its prevalence ranges from 3.8%-7.8% in the population. The gold standard for its diagnosis is the neurophysiological study (85% sensitivity and 95% specificity), with the disadvantage of being invasive, complex and expensive, which means an increase in cost and time for the diagnosis of the disease. The main objective of this diagnostic test evaluation study is to investigate the value of ultrasound in the diagnosis of CTS, and among the secondary objectives, to establish the ultrasound parameters that are predictors of CTS in comparison with neurophysiological studies, attempting to standardize a protocol and reference values that determine the presence or absence of CTS.

METHODS

Prospective, cross-sectional study. The reference test with which we compared the ultrasound is the neurophysiological test (NPT). Patients will come consecutively from the Neurophysiology Department of the Virgen Macarena Hospital, with clinical suspicion of CTS and fulfilling the inclusion/exclusion criteria. To calculate the sample size (EPIDAT program) we proposed a sensitivity of 78% and specificity of 87% with a confidence level of 95%, requiring 438 patients (264 NPT positive, 174 NPT negative). We followed an ultrasound study protocol that included the ultrasound variables: cross-sectional area at the entrance and exit of the tunnel, range of nerve thinning, wrist-forearm index, flexor retinaculum bulging, power Doppler uptake and the existence of adjacent wrists or masses. We propose a timeline for the study to be performed between 2020 and 2023. Finally, we propose a cost-effectiveness analysis.

DISCUSSION

Ultrasound not only allows to objectify the alterations of the median nerve but also the underlying pathological mechanisms in CTS. A multitude of ultrasound parameters have been described that should be regarded in syndrome's study, among which we included the cross-sectional area, the range of nerve thinning, the wrist-forearm index, flexor retinaculum bulging, power Doppler uptake and assessment of anatomical alterations. The use of ultrasound as a diagnostic tool in CTS has many advantages for both doctors and the patients, as it is a non-invasive, convenient, and fast tool increasingly accessible to professionals.

TRIAL REGISTRATION

Trials registry number: NCT05556278.

[Not Available]

Diagnosis of Carpal Tunnel Syndrome: Value of Ultrasound Compared to Nerve Conduction Studies Abstract. Carpal tunnel syndrome is the most common compression syndrome of the peripheral nerves. The patient's history with nocturnal brachialgia, daytime brachialgia, nocturnal paraesthesia and daytime paraesthesia (part of the 6-item CTS symptom scale) and a specific clinical exam take part while making a diagnosis. Additional diagnostics include electrophysiological testings. A high-resolution ultrasound examination for the evaluation of the morphology of the median nerve has gained importance in diagnosis of a carpal tunnel syndrome, whilst an electrophysiological exam allows a functional evaluation. Cardinal finding in ultrasound is an absolute or relative enlargement of the cross-section of the nerve at the edge proximal to the flexor retinaculum. Despite multiple studies that demonstrated ultrasound as a fist-line diagnostic tool, there is no consensus on optimal sonographic criteria for the definition of a compressed median nerve. Our aim was to demonstrate the use of ultrasound and electrophysiological exams for diagnostics of carpal tunnel syndrome in our own patient population and compared to the literature.

Impact of keyboard typing on the morphological changes of the median nerve

Objectives:

The primary objective was to investigate the effects of continuous typing on median nerve changes at the carpal tunnel region at two different keyboard slopes (0° and 20°). The secondary objective was to investigate the differences in wrist kinematics and the changes in wrist anthropometric measurements when typing at the two different keyboard slopes.

Methods:

Fifteen healthy right-handed young men were recruited. A randomized sequence of the conditions (control, typing I, and typing II) was assigned to each participant. Wrist anthropometric measurements, wrist kinematics data collection and ultrasound examination to the median nerve was performed at designated time block.

Results:

Typing activity and time block do not cause significant changes to the wrist anthropometric measurements. The wrist measurements remained similar across all the time blocks in the three conditions. Subsequently, the wrist extensions and ulnar deviations were significantly higher in both the typing I and typing II conditions than in the control condition for both wrists (p<0.05). Additionally, the median nerve cross-sectional area (MNCSA) significantly increased in both the typing I and typing II conditions after the typing task than before the typing task. The MNCSA significantly decreased in the recovery phase after the typing task.

Conclusions:

This study demonstrated the immediate changes in the median nerve after continuous keyboard typing. Changes in the median nerve were greater during typing using a keyboard tilted at 20° than during typing using a keyboard tilted at 0°. The main findings suggest wrist posture near to neutral position caused lower changes of the median nerve.

Role of sonographic imaging in occupational therapy practice

Occupational therapy practice is grounded in the delivery of occupation-centered, patient-driven treatments that engage clients in the process of doing to improve health. As emerging technologies, such as medical imaging, find their way into rehabilitation practice, it is imperative that occupational therapy practitioners assess whether and how these tools can be incorporated into treatment regimens that are dually responsive to the medical model of health care and to the profession's foundation in occupation. Most medical imaging modalities have a discrete place in occupation-based intervention as outcome measures or for patient education; however, sonographic imaging has the potential to blend multiple occupational therapy practice forms to document treatment outcomes, inform clinical reasoning, and facilitate improved functional performance when used as an accessory tool in direct intervention. Use of medical imaging is discussed as it relates to occupational foundations and the professional role within the context of providing efficient, effective patient-centered rehabilitative care.

Carpal tunnel syndrome severity staging using sonographic and clinical measures

INTRODUCTION

Ultrasonography may be valuable in staging carpal tunnel syndrome severity, especially by combining multiple measures. This study aimed to develop a preliminary severity staging model using multiple sonographic and clinical measures.

METHODS

Measures were obtained in 104 participants. Multiple categorization structures for each variable were correlated to diagnostic severity based on nerve conduction. Goodness-of-fit was evaluated for models using iterative combinations of highly correlated variables. Using the best-fit model, a preliminary scoring system was developed, and frequency of misclassification was calculated.

RESULTS

The severity staging model with best fit (rho 0.90) included patient-reported symptoms, functional deficits, provocative testing, nerve cross-sectional area, and nerve longitudinal appearance. An 8-point scoring scale classified severity accurately for 79.8% of participants.

CONCLUSIONS

This severity staging model is a novel approach to carpal tunnel syndrome evaluation. Including more sensitive measures of nerve vascularity, nerve excursion, or other emerging techniques may refine this preliminary model.