What Are the Symptoms of ALS?
Apr 18, 2022
Source: Cainiu Health
Dr. He Haochen
Introduction
Typically, asymmetric muscle weakness in the hands appears first, manifesting as delayed fine motor tasks such as buttoning clothes or turning a key in a lock, along with reduced grip strength. The condition progresses slowly; hand weakness becomes increasingly pronounced and is accompanied by atrophy of the small hand muscles—particularly the thenar and hypothenar eminences, interossei, and lumbricals. The disease gradually extends proximally to involve the forearm, upper arm, and shoulder girdle musculature, with visible muscle fasciculations in the atrophic regions.
In daily life, some individuals develop amyotrophic lateral sclerosis (ALS), commonly known as “frozen person syndrome.” However, early symptoms are often overlooked. So, what are the symptoms of ALS?
What Are the Symptoms of ALS?
The disease typically begins with asymmetric muscle weakness in the hands—manifesting as delayed fine motor tasks such as buttoning clothes or turning a key in a lock—and reduced grip strength. The condition progresses slowly, with increasing hand weakness and atrophy of small hand muscles, notably the thenar and hypothenar eminences, interossei, and lumbricals. Atrophy gradually extends to the forearm, upper arm, and shoulder girdle muscles, accompanied by visible muscle fasciculations in affected areas. Shortly after upper-limb involvement, lower-limb symptoms emerge—including weakness, stiffness, and incoordination—often resulting in foot drop during walking. Physical examination reveals muscle atrophy and diminished strength in both upper limbs, with distal involvement more pronounced than proximal; some patients develop a characteristic “claw-hand” deformity. Fasciculations are readily observed in atrophic muscles; muscle tone is typically normal or only mildly increased, yet deep tendon reflexes are hyperactive, and Hoffman’s sign is positive. Lower limbs exhibit spastic paralysis, with increased muscle tone, hyperreflexia, and positive pathological signs. Systemic objective examinations usually yield no abnormalities, although patients frequently report subjective sensory symptoms such as numbness or sensations akin to having a cold.
As the disease advances, muscle weakness and atrophy spread to the trunk and neck muscles, eventually involving the facial and bulbar-innervated muscles—leading to dysarthria (slurred speech), dysphagia (difficulty swallowing), and impaired mastication. Notably, tongue atrophy and fasciculations are distinctive exceptions: they appear early in the disease course and may even be the initial presenting symptom. Bilateral corticobulbar tract involvement leads to dysarthria and dysphagia secondary to pseudobulbar palsy. Among facial muscles, the orbicularis oris is most prominently affected, while extraocular muscles remain spared. Sphincter function and consciousness are preserved. In advanced stages, bilateral sternocleidomastoid muscle atrophy impairs head rotation and elevation, rendering swallowing impossible and necessitating enteral feeding via nasogastric tube. Respiratory muscle fatigue commonly causes dyspnea, chest tightness, and weak coughing; diaphragmatic and intercostal muscle paralysis predisposes patients to aspiration pneumonia and respiratory failure.
ALS severely compromises quality of life; therefore, close monitoring of symptoms and timely intervention are essential. We hope this information proves helpful to you.
