What is an early manifestation of amyotrophic lateral sclerosis (ALS)?

Weakness of the distal extremities is considered an early manifestation of amyotrophic lateral sclerosis (ALS) because one of the hallmark signs of the disease is the progressive weakness and atrophy of voluntary muscles. ALS primarily affects motor neurons in the brain and spinal cord, leading to muscle weakness. Initially, many patients may notice weakness in the hands and feet, which can manifest as difficulty in tasks that require fine motor skills or weakness when standing or walking. This early symptom is critical for identifying ALS, as it sets the stage for further progression of the condition where lower and upper motor neuron signs become more evident.

In contrast, options such as increased muscle strength are not associated with ALS, as the disease is characterized by muscle atrophy and weakness. Severe headaches are not typical of ALS, as the condition primarily affects motor function rather than causing pain. Muscle spasms can occur in ALS, but they are usually not the first sign and occur later in the disease as muscle control deteriorates.