Related Experiment Video
Updated: Aug 12, 2025
08:16
Utility of Dissociated Intrinsic Hand Muscle Atrophy in the Diagnosis of Amyotrophic Lateral Sclerosis
Published on: March 4, 2014
32.1K
Split phenomena in amyotrophic lateral sclerosis: Current evidences, pathogenetic hypotheses and diagnostic
Stefano Zoccolella1,2, Alessia Giugno1,3, Giancarlo Logroscino1,4
1Center for Neurodegenerative Diseases and the Aging Brain, University of Bari Aldo Moro at Pia Fondazione "Card. G. Panico", Tricase, Italy.
Frontiers in Neuroscience
|January 26, 2023
Summary
Amyotrophic lateral sclerosis (ALS) diagnosis can be aided by "split-hand" and "split-leg" signs, which indicate specific muscle atrophy patterns. These signs are valuable for early detection and differentiating ALS from other motor neuron diseases.
Area of Science:
- Neurology
- Neurophysiology
Background:
- Amyotrophic lateral sclerosis (ALS) is a progressive motor neuron disease with increasing incidence.
- Diagnosis relies on clinical findings, with electromyography (EMG) and nerve conduction studies (NCS) excluding other lower motor neuron (LMN) dysfunctions.
Purpose of the Study:
- To review current evidence on "split-hand" (SH) and "split-leg" (SL) signs in ALS.
- To explore pathogenetic hypotheses and neurophysiological findings related to SH and SL signs.
- To analyze the reliability of SH and SL signs in the differential diagnosis and prognosis of ALS.
Main Methods:
- Review of existing literature on SH and SL signs in ALS.
- Analysis of pathogenetic hypotheses and neurophysiological data.
- Evaluation of diagnostic and prognostic utility of SH and SL signs.
Main Results:
- SH and SL signs represent a peculiar pattern of dissociated atrophy in intrinsic hand and foot muscles.
- These signs are observed in a significant proportion of ALS subjects, even early in the disease.
- SH and SL signs are rarely present in other neurological or non-neurological conditions.
Conclusions:
- SH and SL signs may serve as valuable clinical markers in ALS.
- These signs show potential for differential diagnosis and prognosis in ALS patients.
- Further research into neurophysiological underpinnings and diagnostic accuracy is warranted.
Related Concept Videos
01:15Parkinson's Disease: Overview
641
Neurodegenerative disorders are progressive diseases that cause irreversible damage and loss to neurons in specific brain areas. Examples of these disorders include Parkinson's disease, Alzheimer's disease, Multiple Sclerosis (MS), and Amyotrophic Lateral Sclerosis (ALS). These disorders share characteristics such as proteinopathies, selective neuronal vulnerability, and a complex interplay between genetic and environmental factors. The primary therapeutic goal for these conditions is...
641
03:03Amyloid Fibrils
9.7K
Amyloid fibrils are aggregates of misfolded proteins. Under most circumstances, misfolded proteins are either refolded by chaperone proteins or degraded by the proteasome. However, in the case of a mutation or a disease, these proteins can accumulate to form large clusters and often further assemble to form elongated fibers, called fibrils.
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining,...
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining,...
9.7K
01:27Psychosis: Pathophysiology of Schizophrenia and Other Psychotic Disorders
826
Schizophrenia is a neurodevelopmental disorder whose origins are rooted in complex genetic components. Despite our burgeoning understanding, the pathophysiology of this disorder remains incompletely deciphered.
Researchers have identified genetic factors that increase susceptibility to schizophrenia, underscoring the intricate interplay between genetics and environment in disease development. At the core of schizophrenia's pathophysiology is excessive dopaminergic neurotransmission within...
Researchers have identified genetic factors that increase susceptibility to schizophrenia, underscoring the intricate interplay between genetics and environment in disease development. At the core of schizophrenia's pathophysiology is excessive dopaminergic neurotransmission within...
826
01:22Lysosomal Hydrolases
3.9K
Lysosomes are the site for the degradation of macromolecules and biological polymers released during membrane trafficking events such as secretory, endocytic, autophagic, and phagocytic pathways. The membrane-enclosed area of the lysosome, called the lumen, contains hydrolytic enzymes active in an acidic environment. These acid hydrolases are functional at a pH between 4.5 and 5 and are involved in cellular processes such as cell signaling, energy metabolism, restoration of the plasma membrane,...
3.9K