Compression of the C8 and T1 spinal nerves leads to weakness in which finger movement?

Compression of the C8 and T1 spinal nerves leads to weakness in which finger movement?

• A. Flexion of the index finger
• B. Extension of the index finger
• C. Adduction of the index finger
• D. Abduction of the little finger

Answer: (C)

The correct answer focuses on the function of the C8 and T1 spinal nerves, which are part of the brachial plexus and are crucial for the motor innervation of the hand's intrinsic muscles, particularly those responsible for finger movements. Compression of the C8 and T1 spinal nerves can lead to weakness in the movements that involve the ulnar nerve, as both of these nerve roots contribute to the ulnar nerve's function. One of the key roles of the ulnar nerve is to innervate the muscles responsible for adduction of the fingers, specifically the interossei muscles. The interossei muscles are key for adducting the fingers toward the midline of the hand and play a significant role in grasping and gripping actions. Given this, weakness in the ability to adduct the index finger would be expected with C8 and T1 nerve root compression, as these roots are integral to the motor function of the ulnar nerve. Other finger movements such as flexion and extension of the index finger are primarily controlled by different muscle groups, therefore they wouldn't be primarily affected by compression of the C8 and T1 spinal nerves. Thus, weakness in the adduction of the index finger correctly corresponds

The correct answer focuses on the function of the C8 and T1 spinal nerves, which are part of the brachial plexus and are crucial for the motor innervation of the hand's intrinsic muscles, particularly those responsible for finger movements.

Compression of the C8 and T1 spinal nerves can lead to weakness in the movements that involve the ulnar nerve, as both of these nerve roots contribute to the ulnar nerve's function. One of the key roles of the ulnar nerve is to innervate the muscles responsible for adduction of the fingers, specifically the interossei muscles. The interossei muscles are key for adducting the fingers toward the midline of the hand and play a significant role in grasping and gripping actions.

Given this, weakness in the ability to adduct the index finger would be expected with C8 and T1 nerve root compression, as these roots are integral to the motor function of the ulnar nerve. Other finger movements such as flexion and extension of the index finger are primarily controlled by different muscle groups, therefore they wouldn't be primarily affected by compression of the C8 and T1 spinal nerves.

Thus, weakness in the adduction of the index finger correctly corresponds