Final answer:
Sensory and motor functions can be impaired by damage to the axillary nerve. Sensory perception is hindered when axons from sensory receptors to the CNS are compromised, leading to possible paralysis or lost sensation, depending on the injury's level. Neurological exams pinpoint damage and assess the extent of sensory and motor function loss.
Step-by-step explanation:
Damage to the axillary nerve, a systemic nerve of the arm arising from the brachial plexus, can significantly impact sensory functions and motor controls of the shoulder and upper limb. When axons that carry sensory information from receptors to the central nervous system (CNS) are damaged, the steps of sensory perception are disrupted. This malfunction results in a diminished ability to detect or interpret sensory stimuli from the affected areas. Axons from the dorsal root ganglia entering the spinal cord through the dorsal nerve root carry sensory information, while axons from motor neurons exit through the ventral nerve root to facilitate muscle contraction.
In cases of spinal cord injury, the level and severity of the damage can result in paralysis or loss of sensation below the injury point. Swelling might cause transient symptoms, but severely damaged axons may lead to permanent function loss due to scar tissue and factors inhibiting nerve regrowth. The neurological exam, which includes the sensory and motor exams, allows for the assessment of spinal cord and nerve function and helps to localize the site of the injury. Particularly, this exam aids in determining the impact on sensory and motor function linked to the spinal nerves controlling the muscles tested. The axillary nerve's motor function is crucial for muscles controlling shoulder and arm movements, and sensory impairment could manifest as a loss of sensation in specific areas known as dermatomes.