Preferred sleep position on the side is associated with carpal tunnel syndrome

Sleep postures monitoring based on capacitively coupled electrodes and deep recurrent neural networks

Background

Capacitively coupled electrode (CC electrode), as a non-contact and unobtrusive technology for measuring physiological signals, has been widely applied in sleep monitoring scenarios. The most common implementation is capacitive electrocardiogram (cECG) that could provide useful clinical information for assessing cardiac function and detecting cardiovascular diseases. In the current study, we sought to explore another potential application of cECG in sleep monitoring, i.e., sleep postures recognition.

Methods

Two sets of experiments, the short-term experiment, and the overnight experiment, were conducted. The cECG signals were measured by a smart mattress based on flexible CC electrodes and sleep postures were recorded simultaneously. Then, a classifier model based on a deep recurrent neural network (RNN) was proposed to distinguish sleep postures (supine, left lateral and right lateral). To verify the reliability of the proposed model, leave-one-subject-out cross-validation was introduced.

Results

In the short-term experiment, the overall accuracy of 96.2% was achieved based on 30-s segment, while the overall accuracy was 88.8% using one heart beat segment. For the unconstrained overnight experiment, the accuracy of 91.0% was achieved based on 30-s segment, while the accuracy was 81.4% using one heart beat segment.

Conclusions

The results suggest that cECG could render valuable information about sleep postures detection and potentially be helpful for sleep disorder diagnosis.

High-resolution ultrasound demonstrates in vivo effects of wrist movement on the median nerve along the forearm

INTRODUCTION/AIMS

High-resolution ultrasound (HRUS) is the imaging method of choice to visualize peripheral nerve size, structure, and biomechanical performance. The purpose of this study was to show and quantify the effects of active and passive wrist alignment on median nerve (MN) cross-sectional area (CSA) along the forearm in a healthy population.

METHODS

Sixteen healthy volunteers underwent HRUS of their dominant forearm (n = 16, 10 males, 6 females, 18-55 y of age). Median nerve's CSA was assessed at four defined areas on the forearm in relation to active and passive wrist alignment.

RESULTS

Changes in wrist alignment were significantly associated with MN CSA (P < .001), regardless if the wrist was moved actively or passively. MN CSA was lowest during passive extension of the wrist joint and highest during passive flexion of the wrist joint (range: 4.5-23.2 mm² ).

DISCUSSION

The elasticity of nerve tissue, the loose connective tissue between the fascicles, and the paraneurium allow peripheral nerves to adapt to longitudinal strain. HRUS enables the demonstration of significant median nerve CSA changes along the forearm during active and passive wrist movement in healthy volunteers.

Quantitative Models for Prediction of Cumulative Trauma Disorders Applied to the Maquiladora Industry

Temperature gradient changes on the surface of the skin or in the middle of the body are signs of a disease. The aim of this study is to develop quantitative models for the prediction of cumulative trauma disorders (CTDs) arising from highly repetitive activities, considering risk factors, such as age, gender, body mass index (BMI), blood pressure (BP), respiratory rate (RR), and heart rate, to prevent injuries in manufacturing factory operators. This research involved 19 individuals from the area of sanding and 14 individuals from the area of tolex in manufacturing factories who had their vital signs and somatometry taken, as well as thermal images of their hands in the dorsal and palmar areas; an evaluation by the OCRA method was also applied. Factors such as BP and heart rate were determined to significantly influence the injuries, but no strong association with BMI was found. Quadratic regression models were developed, the estimates of which were adequately adjusted to the variable (R² and R² adjusted > 0.70). When integrating the factors of the OCRA method to the generated models, a better fit was obtained (R² and adjusted R² > 0.80). In conclusion, the participants who present levels out of the normal range in at least one of the factors have high probabilities of developing injuries in their wrists.

Obstructive sleep Apnea's association with the cervical spine abnormalities, posture, and pain: a systematic review

OBJECTIVES

While obstructive sleep apnea (OSA) is associated with several chronic health conditions such as hypertension, obesity, and chronic hypoxia, there is limited information on its association with neuromuscular and spinal pathologies that may be of interest to a musculoskeletal (MSK) medicine or pain management clinician. The objective of this study was to perform a systematic literature review to examine the association between OSA and cervical spine pathologies, postural changes, and pain.

DESIGN

We systematically reviewed PubMed and Embase databases up to 4/15/2019. We included studies that explored associations between OSA and a) pain, b) postural characteristics or changes, or c) cervical spine morphology. Systematic reviews, meta-analysis, randomized control trials, cohort studies, and case-control studies were included. Case reports, narrative reviews or expert opinion papers were excluded. From the articles that met selection criteria, information regarding type, direction and magnitude of such associations was extracted. The OSA-pain association studies were further divided into 3 subgroups: neuropathic, temporomandibular, and chronic pain.

RESULTS

21 articles that met our study criteria were selected for this review. Two studies were on cervical spine pathologies, eight on postural changes, and eleven on pain associated with OSA. Exploring the association between OSA and cervical spine pathologies, postural changes, and pain in this systematic review we found: (1) Cervical spine lesions, fusions, and abnormalities that reduce retropharyngeal space are associated with OSA, likely by way of worsening posture and decreasing range of motion. (2) Head extension and anteriorization are associated with OSA likely as a compensatory mechanism. Extension may improve airway function, while anteriorization helps to maintain visual sense. (3) Head-of-bed-elevation may improve OSA symptoms and can possibly supplement other conservative treatment measures. (4) Neuropathic pain is associated with OSA, likely by way of inflammatory pathways. (5) Oral appliance use (eg mandibular advancement/protruding device) in OSA likely contributes to transient temporomandibular pain. (6) There is little association between OSA and chronic pain prevalence. (7) Increased pain intensity and decreased pain tolerance are somewhat associated with OSA, likely by way of hypoxemia and sleep fragmentation.

CONCLUSIONS

Clinicians in MSK and pain medicine need to consider these associations and consider obtaining imaging studies and/or making referrals for management of their OSA to better provide appropriate care to these patients.

A Review of Carpal Tunnel Syndrome and Its Association with Age, Body Mass Index, Cardiovascular Risk Factors, Hand Dominance, and Sex

Carpal tunnel syndrome (CTS) is one of the most common compressive, canalicular neuropathies of the upper extremities, causing hand pain and impaired function. CTS results from compression or injury of the median nerve at the wrist within the confines of the carpal tunnel. Parameters such as age, sex, and body mass index (BMI) could be risk factors for CTS. This research work aimed to review the existing literature regarding the relationship between CTS and possible risk factors, such as age, sex, BMI, dominant hand, abdominal circumference, respiratory rate, blood pressure, and cardiac rate to determine which ones are the most influential, and therefore, take them into account in subsequent applied research in the manufacturing industry. We performed a literature search in the PubMed, EBSCO, and ScienceDirect databases using the following keywords: carpal tunnel syndrome AND (age OR sex OR BMI OR handedness OR abdominal circumference OR respiratory rate OR blood pressure OR cardiac rate). We chose 72 articles by analyzing the literature found based on selection criteria. We concluded that CTS is associated with age, female sex, and high BMI. Trends and future challenges have been proposed to delve into the relationship between risk factors and CTS, such as correlation studies on pain reduction, analysis of weight changes to predict the severity of this pathology, and its influence on clinical treatments.

Can human posture and range of motion be measured automatically by smart mobile applications?

Human posture and Range of Motion (ROM) are important components of a physical assessment and, from the collected data, it is possible to identify postural deviations such as scoliosis or joint and muscle limitations, hence identifying risks of more serious injuries. Posture assessment and ROM measures are also necessary metrics to monitor the effect of treatments used in the motor rehabilitation of patients, as well as to monitor their clinical progress. These evaluation processes are more frequently performed through visual inspection and manual palpation, which are simple and low cost methods. These methods, however, can be optimized with the use of tools such as photogrammetry and goniometry. Mobile solutions have also been developed to help health professionals to capture more objective data and with less risk of bias. Although there are already several systems proposed for assessing human posture and ROM in the literature, they have not been able to automatically identify and mark Anatomical and Segment Points (ASPs). The hypothesis presented here considers the development of a mobile application for automatic identification of ASPs by using machine learning algorithms and computer vision models associated with technologies embedded in smartphones. From ASPs identification, it will be possible to identify changes in postural alignment and ROM. In this context, our view is that an application derived from the hypothesis will serve as an additional tool to assist in the physical assessment process and, consequently, in the diagnosis of disorders related to postural and movement changes.

Relationship between electrodiagnostic findings and sleep disturbance in carpal tunnel syndrome: A controlled objective and subjective study

Objective

This controlled objective and subjective study aimed to evaluate the relationship between insomnia severity and electrodiagnostic findings in patients with carpal tunnel syndrome (CTS).

Methods

Twenty-one patients with an established clinical and electrodiagnostic diagnosis of CTS before surgery were included. Sleep characteristics were monitored objectively over 4 to 9 nights by means of actigraphy. On the following morning, participants completed a sleep log that conveyed their subjective impressions of how they had slept. All patients also completed the Insomnia Severity Index questionnaire. The correlation of these findings with patients’ motor latency and sensory latency was evaluated using Spearman correlation analysis.

Results

We found no correlation between sensory or motor latencies and all sleep measures.

Conclusion

Electrodiagnostic findings and sleep severity in patients with CTS appear to be independent measures, and they do not correlate with each other.

Preferences in Sleep Position Correlate With Nighttime Paresthesias in Healthy People Without Carpal Tunnel Syndrome

BACKGROUND

Carpal tunnel syndrome has been associated with sleep position preferences. The aim of this study is to assess self-reported nocturnal paresthesias and sleeping position in participants with and without carpal tunnel syndrome diagnosis to further clinical knowledge for preventive and therapeutic interventions.

METHODS

A cross-sectional survey study of 396 participants was performed in young adults, healthy volunteers, and a patient population. Participants were surveyed on risk factors for carpal tunnel syndrome, nocturnal paresthesias, and sleep preferences. Binary logistic regression analysis was performed comparing participants with rare and frequent nocturnal paresthesias. Subanalyses for participants without carpal tunnel syndrome under and over 21 years of age were performed on all factors significantly associated with subclinical compression neuropathy in the overall population.

RESULTS

Thirty-three percent of the study population experienced nocturnal paresthesias at least weekly. Increased body mass index ( P < .001) and sleeping with the wrist flexed ( P = .030) were associated with a higher frequency of nocturnal paresthesias. Side sleeping was associated with less frequent nocturnal symptoms ( P = .003). In participants without carpal tunnel syndrome, subgroup analysis illustrated a relationship between nocturnal paresthesias and wrist position. In participants with carpal tunnel syndrome, sleeping on the side had a significantly reduced frequency of nocturnal paresthesias.

CONCLUSION

This study illustrates nocturnal paresthesias in people without history of carpal tunnel syndrome including people younger than previously reported. In healthy patients with upper extremity subclinical compression neuropathy, sleep position modification may be a useful intervention to reduce the frequency of nocturnal symptoms prior to developing carpal tunnel syndrome.

In-Bed Pose Estimation: Deep Learning With Shallow Dataset

This paper presents a robust human posture and body parts detection method under a specific application scenario known as in-bed pose estimation. Although the human pose estimation for various computer vision (CV) applications has been studied extensively in the last few decades, the in-bed pose estimation using camera-based vision methods has been ignored by the CV community because it is assumed to be identical to the general purpose pose estimation problems. However, the in-bed pose estimation has its own specialized aspects and comes with specific challenges, including the notable differences in lighting conditions throughout the day and having pose distribution different from the common human surveillance viewpoint. In this paper, we demonstrate that these challenges significantly reduce the effectiveness of the existing general purpose pose estimation models. In order to address the lighting variation challenge, the infrared selective (IRS) image acquisition technique is proposed to provide uniform quality data under various lighting conditions. In addition, to deal with the unconventional pose perspective, a 2- end histogram of oriented gradient (HOG) rectification method is presented. The deep learning framework proves to be the most effective model in human pose estimation; however, the lack of large public dataset for in-bed poses prevents us from using a large network from scratch. In this paper, we explored the idea of employing a pre-trained convolutional neural network (CNN) model trained on large public datasets of general human poses and fine-tuning the model using our own shallow (limited in size and different in perspective and color) in-bed IRS dataset. We developed an IRS imaging system and collected IRS image data from several realistic life-size mannequins in a simulated hospital room environment. A pre-trained CNN called convolutional pose machine (CPM) was fine-tuned for in-bed pose estimation by re-training its specific intermediate layers. Using the HOG rectification method, the pose estimation performance of CPM improved significantly by 26.4% in the probability of correct key-point (PCK) criteria at PCK0.1 compared to the model without such rectification. Even testing with only well aligned in-bed pose images, our fine-tuned model still surpassed the traditionally tuned CNN by another 16.6% increase in pose estimation accuracy.

The effectiveness of splinting and surgery on sleep disturbance in carpal tunnel syndrome

This controlled prospective study assessed the effectiveness of night splinting compared with non-splinting and surgery for severity of insomnia in patients with carpal tunnel syndrome. Sleep characteristics were observed for several days without a brace, with a brace and after surgery. The sleep measurements included the use of an actigraph worn on the wrist during night, a 'sleep log' that conveyed subjective impressions as to how the patient had slept and a short insomnia instrument, the Insomnia Severity Index. The Insomnia Severity Index scores showed that a night splint significantly improved insomnia symptoms compared with no splinting, and surgery significantly improved insomnia symptoms compared with splinting. The sleep log scores showed that the sleep quality and the number of awakenings when a splint was not worn were significantly different from the scores with the splint and the scores after surgery but showed no differences between splint and surgery. The actigraph did not show any significant differences between the treatment methods.

LEVEL OF EVIDENCE

III.

Evaluation and Management of Sleep Disorders in the Hand Surgery Patient

Despite posing a significant public health threat, sleep disorders remain poorly understood and often underdiagnosed and mismanaged. Although sleep disorders are seemingly unrelated, hand surgeons should be mindful of these because numerous conditions of the upper extremity have known associations with sleep disturbances that can adversely affect patient function and satisfaction. In addition, patients with sleep disorders are at significantly higher risk for severe, even life-threatening medical comorbidities, further amplifying the role of hand surgeons in the recognition of this condition.

Carpal Tunnel Syndrome in Obstructive Sleep Apnea Patients

Introduction

Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy of the upper extremity. It is usually associated with the compression of the median nerve in the median groove. Because the main symptoms of CTS pain and numbness worsen at night, sleep disorders in CTS patients and the impact of preferred sleeping position on CTS development have been formerly studied. However, to the best of our knowledge, this is the first study assessing the frequency of CTS in obstructive sleep apnea (OSA) patients. This study aimed to determine the frequency of CTS in OSA patients and evaluate the causative relation between the two diseases.

Methods

Records of individuals who were admitted to our sleep laboratory were retrospectively scanned. Eighty patients who were diagnosed with OSA and did not have comorbidities that might cause OSA (e.g., diabetes mellitus, hypothyroiditis, rheumatic diseases, and cervical radiculopathy) were included in the study along with 80 healthy controls who matched for age, sex, and BMI of OSA patients. To maintain observer blindness, patients were not questioned regarding their symptoms or the clinical data that would be used in the study. All participants underwent nerve conduction studies. Those who were diagnosed with CTS were questioned regarding CTS symptoms and the preferred sleeping position. Subsequently, patients were given the Boston CTS questionnaire.

Results

CTS frequency in OSA patients was found to be 27.5%. There was no significant relation between preferred sleeping position or being a manual worker and having CTS.

Conclusion

CTS frequency in OSA patients is significantly higher than that in healthy individuals. In contrast to previous studies that have been performed in the absence of polysomnographic and electrophysiological data, in our study biomechanical factors were not associated with CTS presence. Therefore, we conclude that intermittent hypoxemia is the main etiological factor for CTS in OSA patients. Inflammation may be a common factor for etiopathogenesis for both diseases, but this hypothesis needs further investigation.

Characteristics of sleep disturbance in patients with carpal tunnel syndrome

BACKGROUND

Sleep disturbance is common in carpal tunnel syndrome (CTS), and we hypothesize that it has an important impact on the quality of life of CTS patients. The characteristic of sleep problems associated with CTS has not been evaluated.

METHODS

We performed a case-control study to measure the association between a variety of sleep disturbances and CTS. Sixty-two cases with clinically diagnosed CTS and a probable or classic hand diagram were compared to 138 primary care patients without CTS. In addition to demographic features, we collected the nature of sleep disturbance experienced by the patients from a categorical list and the nature, impact, and severity of sleep disturbance using the Insomnia Severity Index.

RESULTS

Patients with CTS complained of significantly more severe problems with sleep than the control population and had multiple sleep complaints compared to the control group. Sixty-three of the 138 control patients indicated that they had one cause of sleeping disturbance with no control patient choosing more than one. In contrast, in CTS patients, 44 of 63 patients indicated they had two or more causes of sleep disturbance. The Insomnia Severity Index was significantly higher in CTS patients and the impact of sleep disturbance on quality of life was higher in the cases.

CONCLUSION

Sleep disturbance in CTS patients is characterized by a broad array of physical symptoms that have a significant impact on quality of life.