Reflex Hammer Research Articles

History and Evolution of the Reflex Hammer.

This paper is a summary of the history and development of the reflex hammer, a crucial part of the neurologic examination. It goes through the evolution of the reflex hammer, beginning with the initial concepts of reflexes, and concludes with the most recent designs of reflex hammers that can record their own data to reduce error. The reflex hammer has undergone many changes through time to become the important medical tool that it is today.

Possibilities and prospects for assessing pain nociception in patients with chronic disorders of consciousness

The objective was to study the possibilities of assessing pain nociception in patients with chronic disorders of consciousness (CDC) using the ANI index and to identify differences depending on the level of CDC, to create systems for objectification of pain sensations of patients with CDC. Materials and methods. The study included 29 patients with CDC. Group 1 (9 patients) – vegetative state / unresponsive wakefulness syndrome (VS/UWS), group 2 (20 patients) – minimally conscious state (MCS) – “plus”. The pain stimulus (PS) consisted in pressing on the nail phalanx of the hand with a reflex hammer. The ANI index was recorded three times: at rest (ANI 1), during the application of PS (ANI 2), 30 minutes after the application of PS (ANI 3). The assessment on the pain scale (NCS-R) was performed once during the application of PS. Statistical processing was carried out using the R programming language, a package of applied statistical programs SPSS STATISTICS.Results. The average values of the index difference ANI 2 and ANI 1 in group 1 differed, ANI 2 – ANI 3 had no differences. The average values of the ANI 3 index in groups 1 and 2 differed statistically significantly. A rank correlation between the ANI index and the NCS-R score existed in group 1 in the period after the application of BS. A statistically significant negative correlation was found in group 1 during the application of BS. When comparing the ANI index and the difference between the CRS-R index at discharge and admission, it was found that in group 2, the greater the difference between the CRS-R index at discharge and admission, the lower the value of the ANI index at all stages of the study, and in group 1 the opposite relationship was obtained. In group 1, there was a statistical relationship between the Kerdo index (IR) and the difference between the indices ANI 2 and ANI 1, ANI 2 and ANI 1 and IR, for group 2, the relationship could not be established.Conclusion. The data obtained during the study indicate that there are certain differences in the response to PS in patients in the VS / UWS and MCS ≪plus≫. Сreation of systems for objectification of pain sensations of patients in the VS / UWS will contribute to improving their quality of life.

History and national survey on reflex hammers: which is the chosen one of Brazilian neurologists?

Percussion is an important part of the neurological examination and reflex hammers are necessary to obtain it properly. We aimed to review the historical aspects of the main reflex hammers and to define the favorite one of Brazilian neurologists. We searched original and review articles about historical aspects of the reflex hammers in Scielo and Pubmed and conducted an online survey to investigate the favorite reflex hammer of Brazilian neurologists. In the first part, we describe the major milestones in the creation of the reflex hammers. Following, we exhibit the results of the online survey: Babinski-Rabiner was the most voted. The origins of the reflex hammers goes back long before their creation, from a basic clinical examination method: percussion. Since the description of deep tendon reflexes and the creation of percussion hammers, much has been improved in this technique. Among all the hammers surveyed, the Babinski-Rabiner was the chosen one by a significant portion of Brazilian neurologists.

A Highly Sensitive Multimodal Tactile Sensing Module with Planar Structure for Dexterous Manipulation of Robots

Herein, a multimodal tactile sensing module that can improve the dexterous manipulation capabilities of robots with parallel grippers is reported. The tactile sensor consists of a 4 × 4 matrix 3‐axis force sensor array (with spacings of 2 mm) and a single‐temperature sensor. The tactile sensor uses inorganic silicon and gold as materials for the detection of strain and temperature and a polymer‐based elastomer to encapsulate the sensing layer. The sensing module is equipped with a readout circuitry for signal processing. Within the measurable force range (≈1.5 N) of the sensor cell, a prototype module exhibits a repeatability error within 2%, a hysteresis error within 3%, and a resolution as small as 10 mN. Furthermore, each sensor cell independently measures 3‐axis forces with a cross‐talk error of approximately 3%. The temperature sensor exhibits linear output properties in the approximate range of 5–75 °C. Experiments are performed by mounting the module on a parallel gripper to grasp a paper cup and a reflex hammer toy. According to the experimental results, the sensor can accurately detect the state of contact with an object by analyzing three tactile modalities (i.e., 3‐axis force distribution, vibration, and temperature).

Clinical Practice Guidelines for the Use of Electroconvulsive Therapy.

Clinical Practice Guidelines for the Use of Electroconvulsive Therapy.

Analysis of bacterial contamination and the effectiveness of UV light-based reprocessing of everyday medical devices.

The reprocessing of daily used medical devices is often inadequate, making them a potential source of infection. In addition, there are usually no consistent and technically standardized procedures available for this purpose. Hence, the aim of this study is to analyze the bacterial contamination and the effectiveness of Ultraviolet light-based (UV light-based) reprocessing of daily used medical devices. Six different everyday medical devices (20 each; stethoscopes, tourniquets, bandage scissors, reflex hammers, tuning forks, and nystagmus glasses) were tested for bacterial contamination. All medical devices were then exposed to UV-C light for 25 seconds. Medical devices with a smooth surface were pre-cleaned with a water-based wipe. Contact samples were taken before and after reprocessing. Immediately after clinical use, 104 of 120 contact samples showed an average bacterial contamination of 44.8±64.3 colony forming units (CFU) (0-300 CFU), also including potentially pathogenic bacteria. Two further culture media were completely overgrown with potentially pathogenic bacteria. The stethoscopes were found to have the highest average contamination of 90±91.6 CFU. After reprocessing, 118 of 120 samples were sterile, resulting in an average residual contamination of 0.02±0.1 CFU in two samples, whereby only bacteria of the ordinary skin flora were found. The present study shows the potentially clinically relevant bacterial contamination of everyday used medical devices. The reprocessing method tested here using UV light appears to be a suitable method for disinfection, especially for objects that up to now have been difficult to disinfect or cannot be disinfected in a standardized manner.

Technical note: Practical application of post-mortem mechanical stimulation of skeletal muscle, a field study

BackgroundEstimation of the post-mortem interval (PMI) is a crucial aspect in crime scene investigation. PMI is defined as the time between the moment of death and the moment of finding the dead body. A combination of methods for estimating the PMI in forensic casework is internationally mostly used. Supravital muscle reaction (SMR) is one of those methods. SMR is an idiomuscular contraction and can be provoked by mechanical stimulation.ObjectivesA field study was carried out with the aim to investigate whether a reflex hammer can be used as tool for triggering an idiomuscular contraction and, furthermore, to determine if a learning period has to be taken into account by a forensic physician for appropriate application of a reflex hammer to trigger SMR.MethodsFrom January 2017 to January 2022, four forensic physicians used this SMR by mechanically stimulating the musculus brachioradialis and musculus biceps brachii. In total, 332 cases were included with a PMI less than 24 h. The cases were divided in chronological clusters of 20 cases. The ratio of the number of positive SMR versus the total number stimulations per forensic physician was used as a measure of accuracy of a reflex hammer for triggering SMR. The distribution of the data was analyzed by comparing the clusters in chronological order to assess whether a learning curve applies.ResultsIn 55.7%, a muscle reaction could be provoked by mechanical stimulation. Comparable outcome of SMR between the participating physicians was observed after 40 stimulations.ConclusionA reflex hammer is usable for provoking SMR. A learning period has to be taken in to account during the first forty cases per forensic physician.

Prediction of Single Trial Somatosensory Evoked Potentials From Mechanical Stimulation Intensity.

Somatosensory evoked potentials (SSEPs) are important for both scientific research and the evaluation of treatment efficacy in neurorehabilitation. SSEPs measure the response in the sensorimotor cortex to a peripheral stimulation. Individual responses are often noisy, so SSEPs have typically required hundreds of stimulation-response trials to produce a single measurement. This work presents a method to estimate single trial SSEPs from tendon hammer accelerations. While predictions from the input side can not completely replace actual measurements of SSEPs, the results produced may help to provide clinicians insight where full scale SSEP measurement is not practical.

What is neurologist seeing with the reflex hammer? ―Neurological examination―

What is neurologist seeing with the reflex hammer? ―Neurological examination―

Deep Tendon Reflex: The Tools and Techniques. What Surgical Neurology Residents Should Know.

The deep tendon reflex (DTR) is a key component of the neurological examination. However, interpretation of the results is a challenge since there is a lack of knowledge on the important features of reflex responses such as the amount of hammer force, the strength of contraction, duration of the contraction and relaxation. The tools used to elicit the reflexes also play a role in the quality of the reflex contraction. Furthermore, improper execution techniques during the DTR assessment may alter the findings and cloud the true assessment of the nervous system. Therefore, understanding the basic principles and the key features of DTR allows for better interpretation of the reflex responses. This paper discusses the brief history of reflexes, the development of the reflex hammer, and also the key features of a reflex response encompassing the amplitude of force needed to elicit a reflex response, the velocity of contraction, the strength of contraction, and the duration of contraction and relaxation phases. The final section encloses the techniques of eliciting DTR in the upper extremities, trunk, and lower extremities, and the interpretation of these reflexes.

A Smart Tendon Hammer System for Remote Neurological Examination

The deep tendon reflex exam is an important part of neurological assessment of patients consisting of two components, reflex elicitation and reflex grading. While this exam has traditionally been performed in person, with trained clinicians both eliciting and grading the reflex, this work seeks to enable the exam by novices. The COVID-19 pandemic has motivated greater utilization of telemedicine and other remote healthcare delivery tools. A smart tendon hammer capable of streaming acceleration measurements wirelessly allows differentiation of correct and incorrect tapping locations with 91.5% accuracy to provide feedback to users about the appropriateness of stimulation, enabling reflex elicitation by laypeople, while survey results demonstrate that novices are reasonably able to grade reflex responses. Novice reflex grading demonstrates adequate performance with a mean error of 0.2 points on a five point scale. This work shows that by assisting in the reflex elicitation component of the reflex exam via a smart hammer and feedback application, novices should be able to complete the reflex exam remotely, filling a critical gap in neurological care during the COVID-19 pandemic.

An intelligent bio-inspired system for detection and prediction of osteoporosis

Osteoporosis, a bone-related disorder that causes bone loss and other medical complications. Osteoporosis diagnosis is a lengthy process and requires a number of procedures. This disease is found to be difficult to detect in remote areas due to lack of high-tech equipment. Vibroacoustic response of bones may recognize the quality of the bone. The signal (Mel-frequency cepstral coefficients) from the reflex hammer which is used in an artificial neural network provides more than 70% accuracy. To avoid the above-mentioned problems and to improve the process of identifying this disease and to improve the efficiency and accuracy of the identification process, we propose this method which helps to determine the chance of this disease in patients by analyzing a classifier using an artificial immune system that classifies the affected and the unaffected using the history of the patient The use of the artificial immune system is 94 per cent effective. The classifier we used therefore defines and predicts the probability of the disease occurring.

Static and dynamic otolith reflex function in people with Parkinson's disease.

Parkinson's disease (PD) is a neurodegenerative disorder with possible vestibular system dysfunction. This study reports the transient and sustained functions of the otoliths and their reflex pathways in PD compared to healthy controls (HC) and determines if otolith function relates to previous fall history. Forty participants with PD and 40 HC had their otolith function assessed. Transient saccular and utricular-mediated reflexes were assessed by cervical and ocular vestibular evoked myogenic potentials (cVEMPs and oVEMPs, respectively) elicited by air-conducted stimulus (clicks) and bone-conducted vibration (light tendon hammer taps). Static otolith function was assessed by the Curator Subjective Visual Vertical (SVV) test. Compared to HC, the PD group had significantly more absent cVEMP responses to both clicks (47.5% vs. 30%, respectively, p = 0.03) and taps (21.8% vs. 5%, respectively, p = 0.002). Only the PD group had bilaterally absent tap cVEMPs, this was related to previous falls history (p < 0. 001). In both groups, click oVEMPs were predominantly absent, and tap oVEMPs were predominantly present. The PD group had smaller tap oVEMP amplitudes (p = 0.03) and recorded more abnormal SVV responses (p = 0.01) and greater error on SVV compared to HC, p < 0.001. SVV had no relationship with VEMP responses (p = 0.14). PD impacts on cVEMP reflex pathways but not tap oVEMP reflex pathways. Bone-conducted otolith stimuli (taps) are more robust than air-conducted sound stimuli (clicks) for both o and cVEMPs. A lack of association between SVV and VEMP responses suggest that static and dynamic otolith functions are differentially affected in PD.

Is this a reflex hammer that I see before me…?

Is this a reflex hammer that I see before me…?

Assessment of the cutaneous trunci reflex in neurologically healthy cats.

The aim of this study was to perform the cutaneous trunci reflex (CTR) in neurologically normal cats using two different instruments and determine how body condition score (BCS), body circumference, age, sex and instrument type may affect this reflex. Sixty-five cats without evidence of neurologic disease were prospectively enrolled. Cats were randomly assigned to have the reflex tested first using a pair of hemostatic forceps or the integrated Babinski tip of an MDF Babinski Buck Reflex Hammer. After 30 mins, the reflex was retested using the other instrument. Data collected included the reflex presence, reflex caudal border, reflex intensity (weak, moderate, strong) and reflex symmetry (unilateral or bilateral). The influence of BCS, body circumference, age and sex on these variables was statistically evaluated along with effect of the instrument used. The CTR was elicited bilaterally in 52 (80%) cats and unilaterally in 64 (98%) cats. In two cats, the CTR was only able to be elicited using the Buck Reflex Hammer, while in four cats, the CTR was only able to be elicited using hemostatic forceps. Body circumference, BCS, age and sex had no effect on the presence, caudal border, intensity or symmetry of the CTR, regardless of the instrument used. No difference in the bilateral presence of the CTR was noted based on the instrument used first (P = 0.53). When assessing the influence of the instrument on reflex presence, caudal border, intensity and symmetry, the hemostatic forceps elicited the reflex further caudally (P = 0.02) and usually bilaterally (P = 0.02). The CTR could be elicited in the majority of cats with both instruments. However, hemostatic forceps elicited a reflex more caudally and bilaterally symmetrical than the Buck Reflex Hammer.

Jean-Martin Charcot´s medical instruments: Electrotherapeutic devices in La Leçon Clinique à la Salpêtrière

ABSTRACT In the famous painting La Leçon Clinique à la Salpêtrière (A Clinical Lesson at the Salpêtrière) by André Brouillet (1857–1914), the neurologist Jean-Martin Charcot (1825–1893) is shown delivering a clinical lecture in front of a large audience. A hysterical patient, Marie Wittman (known as “Blanche”; 1859–1912) is leaning against Charcot’s pupil, Joseph Babinski (1857–1932). Lying on the table close to Charcot are some medical instruments, traditionally identified as a Duchenne electrotherapy apparatus and a reflex hammer. A closer look at these objects reveals that they should be identified instead as a Du Bois-Reymond apparatus with a Grenet cell (bichromate cell) battery and its electrodes. These objects reflect the widespread practice of electrotherapeutic faradization at the Salpêtrière. Furthermore, they allow us to understand the moment depicted in the painting: contrary to what is sometimes claimed, Blanche has not been represented during a hysterical attack, but during a moment of hypnotically induced lethargy.

Wrestle while you learn: EMG as a teaching tool for undergraduate skeletal muscle physiology teaching.

Wrestle while you learn: EMG as a teaching tool for undergraduate skeletal muscle physiology teaching.

Troels Staehelin Jensen-dissecting pain.

Troels Staehelin Jensen-dissecting pain.

Time for Neurologists to Drop the Reflex Hammer on Hypertension

Time for Neurologists to Drop the Reflex Hammer on Hypertension

A Tendon Indentation Method to Quantify Velocity-Dependent Reflex Responses after Hemispheric Stroke.

Stretch reflex responses in passive muscle can be utilized to assess spasticity in chronic stroke survivors. In this study, we present a different method of eliciting the reflex response by imposing tendon indentation using a linear motor. Specifically, we test a "Ramp-and-hold" protocol, utilizing a linear motor controlled by a position-controlled feedback loop (Linmot, Inc), to indent the biceps brachii distal tendon at different velocities. The protocol was tested on the affected arm of three stroke subjects. We also utilized a tendon indentation combined with tendon-tapping method to quantify the reflex threshold. Our results indicate that the reflex response was elicited at velocities equal to or above 50 mm/s in 2/3 subjects. No reflex response was detected in one subject. All subjects showed a distinct reflex threshold using the indentation/tapping method. Furthermore, the presence of a reflex response during tendon-tapping was not necessarily accompanied by the elicitation of a reflex response during the ramp-and-hold. However, our data suggests that the indentation threshold during tapping is correlated to the presence of a reflex response at the velocities tested during the ramp-and-hold. Though more time consuming, tendon indentation using ramp-and-hold could provide greater resolution of the reflex response to quantify spasticity than the current clinically employed ballistic tapping method using a reflex hammer.