Identification of Spared and Proportionally Controllable Hand Motor Dimensions in Motor Complete Spinal Cord Injuries Using Latent Manifold Analysis.

The loss of bilateral hand function is a debilitating challenge for millions of individuals that suffered a motor-complete spinal cord injury (SCI). We have recently demonstrated in eight tetraplegic individuals the presence of highly functional spared spinal motor neurons in the extrinsic muscles of the hand that are still capable of generating proportional flexion and extension signals. In this work, we hypothesized that an artificial intelligence (AI) system could automatically learn the spared electromyographic (EMG) patterns that encode the attempted movements of the paralyzed digits. We constrained the AI to continuously output the attempted movements in the form of a digital hand so that this signal could be used to control any assistive system (e.g. exoskeletons, electrical stimulation). We trained a convolutional neural network using data from 13 uninjured (control) participants and 8 tetraplegic participants (7 motor-complete, 1 incomplete) to study the latent space learned by the AI. Our model can automatically differentiate between eight different hand movements, including individual finger flexions, grasps, and pinches, achieving a mean accuracy of 98.3% within the SCI group. Analysis of the latent space of the model revealed that proportionally controllable movements exhibited an elliptical path, while movements lacking proportional control followed a chaotic trajectory. We found that proportional control of a movement can only be correctly estimated if the latent space embedding of the movement follows an elliptical path (correlation =0.73; p <0.001). These findings emphasize the reliability of the proposed system for closed-loop applications that require an accurate estimate of spinal cord motor output.

Mouth-controlled mouse for quadriplegic disabled people: System design and validation.

Disabled people with a high cervical cord injury or quadriplegia face difficulties when controlling a computer. This study presents a digital mouth-controlled mouse-control aid called the bite-press mouth-controlled mouse (BPMCM) to replace the traditional computer mouse. The BPMCM is equipped with a joystick and micro switch, and the disabled person uses neck and head movements to push the joystick and control the cursor position while the three mouse functions (i.e., left-click, right-click, and drag) are activated by bite-pressing for different time intervals. The proposed design eliminates the sip-and-puff technique and the need to recite orders for reduced adaptation time and increased convenience. Furthermore, this design supports plug-and-play and hot plugging in modern mainstream operating systems that can often be directly operated via mouse functions. Experimental results demonstrated that disabled people using a BPMCM were as capable as healthy participants in operating a computer, with both experiments completed within 5 min, and voluntary disabled people immediately adapted to the BPMCM. The proposed design is expected to allow disabled people to operate computers at the same level as healthy participants. The BPMCM also required only half the physical exertion of other mouth-controlled mouse-control aids that require orders to be recited.

Locked-in syndrome: A qualitative study of a life story.

INTRODUCTION: Locked-in syndrome (LIS) is characterized by tetraplegia, anarthria, paralysis of cranial nerves, and facial musculature, with the preservation of consciousness and cognitive abilities, as well as vertical eye movements and eyelid movements, hearing, and breathing. Three types of LIS are distinguished: classic, incomplete, and total. The aim of the present study was to describe the life history of a person with LIS, as well as the wife's experience and perspective of this life history. METHODS: A qualitative life history study was conducted with two participants: a 54-year-old man diagnosed with LIS and his 50-year-old wife. Data were collected through interviews and autobiographical documents submitted by the participants and analyzed following Braun and Clarke's method of inductive thematic analysis. RESULTS: Five main themes were identified: (1) how to understand and overcome the new situation; (2) the process of care and rehabilitation; (3) communication; (4) writing as a way of helping oneself and others; and (5) personal autonomy and social participation. CONCLUSION: The participants valued the support of their friends and family in the acceptance stage of the new situation, giving special importance to the communication skills and medical attention received after diagnosis.

Extensor Carpi Radialis Brevis Tendon Transfer for Thumb and Finger Flexion Reconstruction after Failed Extensor Carpi Radialis Brevis Motor Branch Transfer in a Tetraplegic Patient.

Distal nerve transfers can restore precise motor control in tetraplegic patients. When nerve transfers are not successful, tendon transfers may be used for subsequent reconstruction. In this case, an extensor carpi radialis brevis (ECRB) tendon transfer was used to restore thumb and finger flexion following an unsuccessful ECRB to anterior interosseous nerve transfer in a young tetraplegic patient. Twelve months following tendon transfer, the patient demonstrated functional grip and pinch strength and was using both hands for daily activities. Level of Evidence: Level V (Therapeutic).

Utilizing nerve conduction studies to identify very early Guillain-Barré syndrome and distinguish it from mimics in emergency settings.

INTRODUCTION/AIMS: Accurately diagnosing Guillain-Barré syndrome (GBS) in its early stages and distinguishing it from mimics poses challenges. This study aimed to evaluate the utility of an existing electrodiagnostic criterion in very early GBS (VEGBS) for discerning mimics. Additionally, we explored specific electrophysiological abnormalities in VEGBS to design a new diagnostic criterion for more accurate VEGBS diagnosis. METHODS: We retrospectively identified all patients with flaccid quadriparesis initially suspected of GBS who underwent nerve conduction studies (NCS) ≤4 days from symptom onset. We then retrieved their NCS data and applied an existing electrodiagnostic criterion for sensitivity and specificity analyses based on the final discharge diagnosis. Furthermore, we designed a new criterion based on the observed electrophysiological abnormalities that have maximum specificity and at least 50% sensitivity. RESULTS: Among 70 patients suspected of VEGBS, 44 (63%) received a final diagnosis of GBS, while in 26 (37%), the GBS diagnosis was later refuted. Umapathi's definite criterion exhibited a sensitivity of 61.36% and a specificity of 92.31%. The probable and possible groups showed very high sensitivity (90.91% and 100%, respectively); however, specificity was low (57.69% and 30.77%, respectively) in the very early stage. Our proposed criterion demonstrated a sensitivity of 88.64% (CI: 75.44%-96.21%) and a specificity of 96.15% (CI: 80.36%-99.90%). DISCUSSION: The criterion based on presumed electrophysiological correlates of specific early GBS pathophysiology proved more effective than the existing electrodiagnostic criterion in differentiating VEGBS from mimics.

Chasing Gold: Heat Acclimation in Elite Handcyclists with Spinal Cord Injury.

Thermoregulation is impaired in individuals with a spinal cord lesion (SCI), affecting sweat capacity, heat loss, and core temperature. This can be particularly problematic for athletes with SCI who exercise in hot and humid conditions, like those during the Tokyo 2020 Paralympic Games. Heat acclimation can support optimal preparation for exercise in such challenging environments, but evidence is limited in endurance athletes with SCI. We evaluated whether seven consecutive days of exercise in the heat would result in heat acclimation. Five elite para-cycling athletes with SCI participated (two females, three males, median (Q1-Q3) 35 (31-51) years, four with paraplegia and one with tetraplegia). All tests and training sessions were performed in a heat chamber (30°C and 75% relative humidity). A time-to-exhaustion test was performed on day 1 (pretest) and day 7 (posttest). On days 2-6, athletes trained daily for one hour at 50-60% of individual peak power (PPeak). Comparing pretest and posttest, all athletes increased their body mass loss (p=0.04), sweat rate (p=0.04), and time to exhaustion (p=0.04). Effects varied between athletes for core temperature and heart rate. All athletes appeared to benefit from our heat acclimation protocol, helping to optimize their preparation for the Tokyo 2020 Paralympic Games.

Effects of two external cooling strategies on physiological and perceptual responses of athletes with tetraplegia during and after exercise in the heat.

Athletes with tetraplegia may experience marked hyperthermia while exercising under environmental heat stress due to their limited ability to dissipate heat through evaporative means. This study investigated the effectiveness of two external cooling strategies (i.e., spraying water onto the body surface or using a cooling vest) on physiological and perceptual variables in tetraplegic athletes during and after an aerobic exercise session in a hot environment. Nine male wheelchair rugby players performed an incremental test to determine their maximum aerobic power output. After that, they were subjected to three experimental trials in a counter-balanced order: control (CON, no body cooling), cooling vest (CV), and water spraying (WS). During these trials, they performed 30 min of a submaximal exercise (at 65% of their maximum aerobic power) inside an environmental chamber set to maintain the dry-bulb temperature at 32 °C. The following variables were recorded at regular intervals during the exercise and for an additional 30 min following the exertion (i.e., post-exercise recovery) with the participants also exposed to 32 °C: body core temperature (TCORE), skin temperature (TSKIN), heart rate (HR), rating of perceived exertion (RPE), thermal comfort (TC), and thermal sensation (TS). While exercising in CON conditions, the tetraplegic athletes had the expected increases in TCORE, TSKIN, HR, RPE, and TC and TS scores. HR, TC, and TS decreased gradually toward pre-exercise values after the exercise, whereas TCORE and TSKIN remained stable at higher values. Using a cooling vest decreased the temperature measured only on the chest and reduced the scores of RPE, TC, and TS during and after exercise but did not influence the other physiological responses of the tetraplegic athletes. In contrast, spraying water onto the athletes' body surface attenuated the exercise-induced increase in TSKIN, led to lower HR values during recovery, and was also associated with better perception during and after exercise. We conclude that water spraying is more effective than the cooling vest in attenuating physiological strain induced by exercise-heat stress. However, although both external cooling strategies do not influence exercise hyperthermia, they improve the athletes' thermal perception and reduce perceived exertion.

A Multimodal Assistive-Robotic-Arm Control System to Increase Independence After Tetraplegia.

Following tetraplegia, independence for completing essential daily tasks, such as opening doors and eating, significantly declines. Assistive robotic manipulators (ARMs) could restore independence, but typically input devices for these manipulators require functional use of the hands. We created and validated a hands-free multimodal input system for controlling an ARM in virtual reality using combinations of a gyroscope, eye-tracking, and heterologous surface electromyography (sEMG). These input modalities are mapped to ARM functions based on the user's preferences and to maximize the utility of their residual volitional capabilities following tetraplegia. The two participants in this study with tetraplegia preferred to use the control mapping with sEMG button functions and disliked winking commands. Non-disabled participants were more varied in their preferences and performance, further suggesting that customizability is an advantageous component of the control system. Replacing buttons from a traditional handheld controller with sEMG did not substantively reduce performance. The system provided adequate control to all participants to complete functional tasks in virtual reality such as opening door handles, turning stove dials, eating, and drinking, all of which enable independence and improved quality of life for these individuals.

Representation of internal speech by single neurons in human supramarginal gyrus.

Speech brain-machine interfaces (BMIs) translate brain signals into words or audio outputs, enabling communication for people having lost their speech abilities due to diseases or injury. While important advances in vocalized, attempted and mimed speech decoding have been achieved, results for internal speech decoding are sparse and have yet to achieve high functionality. Notably, it is still unclear from which brain areas internal speech can be decoded. Here two participants with tetraplegia with implanted microelectrode arrays located in the supramarginal gyrus (SMG) and primary somatosensory cortex (S1) performed internal and vocalized speech of six words and two pseudowords. In both participants, we found significant neural representation of internal and vocalized speech, at the single neuron and population level in the SMG. From recorded population activity in the SMG, the internally spoken and vocalized words were significantly decodable. In an offline analysis, we achieved average decoding accuracies of 55% and 24% for each participant, respectively (chance level 12.5%), and during an online internal speech BMI task, we averaged 79% and 23% accuracy, respectively. Evidence of shared neural representations between internal speech, word reading and vocalized speech processes was found in participant 1. SMG represented words as well as pseudowords, providing evidence for phonetic encoding. Furthermore, our decoder achieved high classification with multiple internal speech strategies (auditory imagination/visual imagination). Activity in S1 was modulated by vocalized but not internal speech in both participants, suggesting no articulator movements of the vocal tract occurred during internal speech production. This work represents a proof-of-concept for a high-performance internal speech BMI.

Non-invasive spinal cord electrical stimulation for arm and hand function in chronic tetraplegia: a safety and efficacy trial.

Cervical spinal cord injury (SCI) leads to permanent impairment of arm and hand functions. Here we conducted a prospective, single-arm, multicenter, open-label, non-significant risk trial that evaluated the safety and efficacy of ARCEX Therapy to improve arm and hand functions in people with chronic SCI. ARCEX Therapy involves the delivery of externally applied electrical stimulation over the cervical spinal cord during structured rehabilitation. The primary endpoints were safety and efficacy as measured by whether the majority of participants exhibited significant improvement in both strength and functional performance in response to ARCEX Therapy compared to the end of an equivalent period of rehabilitation alone. Sixty participants completed the protocol. No serious adverse events related to ARCEX Therapy were reported, and the primary effectiveness endpoint was met. Seventy-two percent of participants demonstrated improvements greater than the minimally important difference criteria for both strength and functional domains. Secondary endpoint analysis revealed significant improvements in fingertip pinch force, hand prehension and strength, upper extremity motor and sensory abilities and self-reported increases in quality of life. These results demonstrate the safety and efficacy of ARCEX Therapy to improve hand and arm functions in people living with cervical SCI. ClinicalTrials.gov identifier: NCT04697472 .

Clinical Subsets of Central Cord Syndrome: Is It a Distinct Entity from Other Forms of Incomplete Tetraplegia for Research?

Central cord syndrome (CCS) is the most prevalent and debated incomplete spinal cord injury (SCI) syndrome, with its hallmark feature being more pronounced weakness of the upper extremities than of the lower extremities. Varying definitions encapsulate multiple clinical features under the single umbrella term of CCS, complicating evaluation of its frequency, prognosis discussions, and outcomes research. Often, people with CCS are excluded from research protocols, as it is thought to have a favorable prognosis, but the vague nature of CCS raises doubts about the validity of this practice. The objective of this study was to categorize CCS into specific subsets with clear quantifiable differences, to assess whether this would enhance the ability to determine if individuals with CCS or its subsets exhibit distinct neurological and functional outcomes relative to others with incomplete tetraplegia. This study retrospectively reviewed individuals with new motor incomplete tetraplegia from traumatic SCI who enrolled in the Spinal Cord Injury Model Systems (SCIMS) database from 2010 to 2020. Through an assessment of the prevailing criteria for CCS, coupled with data analysis, we used two key criteria, including the severity of distal upper extremity weakness (i.e., hands and fingers) and extent of symmetry, to delineate three CCS subsets: full CCS, unilateral CCS, and borderline CCS. Of the 1490 participants in our sample, 17.5% had full, 25.6% had unilateral, and 9% had borderline CCS, together encompassing >50% of motor incomplete tetraplegia cases. Despite the increased sensitivity and specificity of these subsets compared with existing quantifiable criteria, substantial variability in clinical presentation was still observed. Overall, individuals meeting CCS subset criteria showed a higher likelihood of American Spinal Injury Association (ASIA) Impairment Scale (AIS) D grade than those with motor incomplete tetraplegia without CCS. Upper Extremity Motor Score (UEMS) for those with CCS was lower on admission, a difference that diminished by discharge, whereas their Lower Extremity Motor Score (LEMS) consistently remained higher than for those without CCS. However, these neurological distinctions did not result in significant functional differences, as lower and upper extremity functional outcomes at discharge were mostly similar, with some differences observed within those with AIS D grade. The AIS grade, rather than the diagnosis of CCS, remains the foremost determinant influencing neurological and functional outcomes. We recommend that future studies consider incorporating motor incomplete tetraplegia into their inclusion/exclusion criteria, instead of relying on criteria specific to CCS. Although there remains clinical value in characterizing an injury pattern as CCS and perhaps using the different subsets to better characterize the impairments, it does not appear to be a useful research criterion.

High intensity functional training for people with spinal cord injury & their care partners.

STUDY DESIGN: Non-randomized clinical trial. OBJECTIVES: Examine the feasibility, physical and psychosocial effects of a high intensity functional training (HIFT) exercise program for people with spinal cord injury (pSCI) and their care partners (CPs). SETTING: Community fitness center in a Medically Underserved Area (Fort Smith, USA.) METHODS: A single-group design with three assessment points (before the program, at midpoint (13 weeks), and post-program (25 weeks) was used to examine the effects of up to 49 HIFT sessions over 25-weeks. Sessions were 60 to 75 min in duration and adapted to the abilities of participants. Feasibility measures included recruitment, retention, attendance, safety and fidelity (exercise intensity rated via session-Rating of Perceived Exertion (RPE). Physical measures included cardiovascular endurance, anaerobic power, and muscular strength. Psychosocial measures included perceived social support for exercise, exercise self-efficacy and health-related quality of life. RESULTS: Fourteen pSCI (7 with paraplegia and 7 with tetraplegia, 2 females) and 6 CPs (4 females) were included (median age = 60) (IQR = 15.8). Recruitment rates were 40% for pSCI and 32% for CPs. On average, participants attended 73% (22%) of exercise sessions with a median session-RPE of 5 (IQR = 1). Retention rates were 83% and 67% for pSCI and CPs, respectively. For pSCI and their CPs, large effect sizes were observed for cardiovascular endurance, anaerobic power, muscular strength, and social support for exercise. CONCLUSIONS: For pSCI and their CPs, HIFT appears feasible and potentially leads to improvements in physical and psychosocial health for both groups.

Wrist extensor pathomechanics: implications for tendon and nerve transfer.

Central and peripheral nervous system lesions may disrupt the intricate balance of the prime movers of the wrist. In spasticity, hyperactive wrist flexors create a flexion moment and, if untreated, can lead to flexion contractures. In patients with C6 spinal cord injury and tetraplegia, the posterior interosseus nerve is typically affected by a complex pattern of upper and/or lower motoneuron lesions causing radial deviation of the wrist due to loss of ulnar deviation actuators. In this report, we illustrate severe pathomechanics that may occur even with relatively modest changes in wrist balance. These results illustrate how thorough understanding of muscle-tendon-joint interaction aids in designing tendon and nerve reconstructive surgeries to normalize wrist positions and balance in neuromuscular conditions.

Learned Motor Patterns Are Replayed in Human Motor Cortex during Sleep.

Consolidation of memory is believed to involve offline replay of neural activity. While amply demonstrated in rodents, evidence for replay in humans, particularly regarding motor memory, is less compelling. To determine whether replay occurs after motor learning, we sought to record from motor cortex during a novel motor task and subsequent overnight sleep. A 36-year-old man with tetraplegia secondary to cervical spinal cord injury enrolled in the ongoing BrainGate brain-computer interface pilot clinical trial had two 96-channel intracortical microelectrode arrays placed chronically into left precentral gyrus. Single- and multi-unit activity was recorded while he played a color/sound sequence matching memory game. Intended movements were decoded from motor cortical neuronal activity by a real-time steady-state Kalman filter that allowed the participant to control a neurally driven cursor on the screen. Intracortical neural activity from precentral gyrus and 2-lead scalp EEG were recorded overnight as he slept. When decoded using the same steady-state Kalman filter parameters, intracortical neural signals recorded overnight replayed the target sequence from the memory game at intervals throughout at a frequency significantly greater than expected by chance. Replay events occurred at speeds ranging from 1 to 4 times as fast as initial task execution and were most frequently observed during slow-wave sleep. These results demonstrate that recent visuomotor skill acquisition in humans may be accompanied by replay of the corresponding motor cortex neural activity during sleep.SIGNIFICANCE STATEMENT Within cortex, the acquisition of information is often followed by the offline recapitulation of specific sequences of neural firing. Replay of recent activity is enriched during sleep and may support the consolidation of learning and memory. Using an intracortical brain-computer interface, we recorded and decoded activity from motor cortex as a human research participant performed a novel motor task. By decoding neural activity throughout subsequent sleep, we find that neural sequences underlying the recently practiced motor task are repeated throughout the night, providing direct evidence of replay in human motor cortex during sleep. This approach, using an optimized brain-computer interface decoder to characterize neural activity during sleep, provides a framework for future studies exploring replay, learning, and memory.

Controlling an effector with eye movements: The effect of entangled sensory and motor responsibilities.

Restoring arm and hand function has been indicated by individuals with tetraplegia as one of the most important factors for regaining independence. The overall goal of our research is to develop assistive technologies that allow individuals with tetraplegia to control functional reaching movements. This study served as an initial step toward our overall goal by assessing the feasibility of using eye movements to control the motion of an effector in an experimental environment. We aimed to understand how additional motor requirements placed on the eyes affected eye-hand coordination during functional reaching. We were particularly interested in how eye fixation error was affected when the sensory and motor functions of the eyes were entangled due to the additional motor responsibility. We recorded participants' eye and hand movements while they reached for targets on a monitor. We presented a cursor at the participant's point of gaze position which can be thought of as being similar to the control of an assistive robot arm. To measure eye fixation error, we used an offline filter to extract eye fixations from the raw eye movement data. We compared the fixations to the locations of the targets presented on the monitor. The results show that not only are humans able to use eye movements to direct the cursor to a desired location (1.04 ± 0.15 cm), but they can do so with error similar to that of the hand (0.84 ± 0.05 cm). In other words, despite the additional motor responsibility placed on the eyes during direct eye-movement control of an effector, the ability to coordinate functional reaching movements was unaffected. The outcomes of this study support the efficacy of using the eyes as a direct command input for controlling movement.

Epidural stimulation with locomotor training ameliorates unstable blood pressure after tetraplegia. A case report.

A male with C7 complete tetraplegia participated in 14 weeks of body weight supported treadmill training (BWSTT) combined with spinal cord epidural stimulation (SCES), 4 weeks of no intervention, and two more weeks of BWSTT + SCES. The participant presented with unstable resting seated blood pressure (BP; 131/66 mmHg). After retrospective analysis, resting systolic BP decreased and diastolic BP increased, yielding a safe mean arterial BP. There was a fivefold increase in BWSTT bouts per session, and percentage of body weight support decreased to 69%. BWSTT + SCES safely and effectively regulated resting BP and mitigated symptoms of orthostatic intolerance. These effects were not maintained after 4 weeks without training.

Sensing and decoding the neural drive to paralyzed muscles during attempted movements of a person with tetraplegia using a sleeve array.

Motor neurons convey information about motor intent that can be extracted and interpreted to control assistive devices. However, most methods for measuring the firing activity of single neurons rely on implanted microelectrodes. Although intracortical brain-computer interfaces (BCIs) have been shown to be safe and effective, the requirement for surgery poses a barrier to widespread use that can be mitigated by instead using noninvasive interfaces. The objective of this study was to evaluate the feasibility of deriving motor control signals from a wearable sensor that can detect residual motor unit activity in paralyzed muscles after chronic cervical spinal cord injury (SCI). Despite generating no observable hand movement, volitional recruitment of motor units below the level of injury was observed across attempted movements of individual fingers and overt wrist and elbow movements. Subgroups of motor units were coactive during flexion or extension phases of the task. Single digit movement intentions were classified offline from the electromyogram (EMG) power [root-mean-square (RMS)] or motor unit firing rates with median classification accuracies >75% in both cases. Simulated online control of a virtual hand was performed with a binary classifier to test feasibility of real-time extraction and decoding of motor units. The online decomposition algorithm extracted motor units in 1.2 ms, and the firing rates predicted the correct digit motion 88 ± 24% of the time. This study provides the first demonstration of a wearable interface for recording and decoding firing rates of motor units below the level of injury in a person with motor complete SCI.NEW & NOTEWORTHY A wearable electrode array and machine learning methods were used to record and decode myoelectric signals and motor unit firing in paralyzed muscles of a person with motor complete tetraplegia. The myoelectric activity and motor unit firing rates were task specific, even in the absence of visible motion, enabling accurate classification of attempted single-digit movements. This wearable system has the potential to enable people with tetraplegia to control assistive devices through movement intent.

Toward Consensus in Assessing Upper Limb Muscle Strength and Pinch and Grip Strength in People With Tetraplegia Having Upper Limb Reconstructions.

OBJECTIVES: To reach agreement on standardized protocols for assessing upper limb strength and grip and pinch force for upper limb reconstructive surgery for tetraplegia. METHODS: Selected members of an expert panel composed of international therapists formed at the 2018 International Congress for Upper Limb Surgery for Tetraplegia conducted a literature review of current practice that identified gaps and inconsistencies in measurement protocols and presented to workshop attendees. To resolve discrepancies, a set of questions was presented to workshop attendees who voted electronically. Consensus was set at 75% agreement. RESULTS: For manual muscle testing, consensus was reached for using the Medical Research Council scale, without plus or minus, and the use of resistance through range when testing grade 4 and grade 5 strength. Pectoralis major and serratus anterior should be routinely tested, however there was no consensus on other shoulder muscles. Grip and pinch strength should be tested according to the American Society of Hand Therapists positioning. For grip strength, either the Jamar or Biometrics dynamometer expressed in kilograms should be used. For grip and pinch strength, three measurements should be performed at each testing. No consensus was reached on a device for pinch strength. CONCLUSION: This work is an important step to enable comparable data in the future. Further consensus methods will work toward developing more comprehensive guidelines in this population. Building international consensus for pre- and postoperative measures of function supports objective evaluation of novel therapies and interpretation of multicenter studies.

Severe acute myopathy following SARS-CoV-2 infection: a case report and review of recent literature.

BACKGROUND: SARS-CoV2 virus could be potentially myopathic. Serum creatinine phosphokinase (CPK) is frequently found elevated in severe SARS-CoV2 infection, which indicates skeletal muscle damage precipitating limb weakness or even ventilatory failure. CASE PRESENTATION: We addressed such a patient in his forties presented with features of severe SARS-CoV2 pneumonia and high serum CPK. He developed severe sepsis and acute respiratory distress syndrome (ARDS) and received intravenous high dose corticosteroid and tocilizumab to counter SARS-CoV2 associated cytokine surge. After 10 days of mechanical ventilation (MV), weaning was unsuccessful albeit apparently clear lung fields, having additionally severe and symmetric limb muscle weakness. Ancillary investigations in addition with serum CPK, including electromyogram, muscle biopsy, and muscle magnetic resonance imaging (MRI) suggested acute myopathy possibly due to skeletal myositis. CONCLUSION: We wish to stress that myopathogenic medication in SARS-CoV2 pneumonia should be used with caution. Additionally, serum CPK could be a potential marker to predict respiratory failure in SARS-CoV2 pneumonia as skeletal myopathy affecting chest muscles may contribute ventilatory failure on top of oxygenation failure due to SARS-CoV2 pneumonia.