15/07/2025
Sensory Level Examination in Suspected
Transverse Myelitis or Spinal Cord Pathologies:
In any neurological examination, especially during short case or long case assessments, it is essential to comment on the sensory level when a spinal cord pathology—such as transverse myelitis—is suspected. Failure to identify and document the sensory level in such cases can significantly undermine the accuracy of the diagnosis and will be penalized in clinical assessments.
The sensory level refers to the lowest level of the spinal cord with normal sensory function.
It helps to localize the lesion within the spinal cord.
In cord lesions like transverse myelitis, sensory deficits typically begin below the level of the lesion and may follow a dermatomal pattern.
Method of Sensory Examination:
Pain Sensation is usually assessed
Use a sterile toothpick or neurological pin.
Begin by testing a spared area—typically the forehead—to establish a reference sensation.
(The head and face are usually unaffected in spinal cord disorders.)
Ask the patient to describe the intensity of the sensation.
Instruct the patient to close their eyes during testing.
Tell them to report:
Whether they feel the stimulus.
If the intensity is the same, less, or absent compared to the reference point(forehead).
Test pain sensation in a dermatomal fashion, starting from the feet upward toward the trunk.
Carefully compare both sides of the body.
If patient has absent sensations or reduced sensations while starting checking feet, then move upward till the point where sensation becomes equal to the reference (forehead).
The level at which normal sensation resumes marks the sensory level.
Important Notes:
In acute seeting patient having impaired sensations below the level lesion, absent at the level of lesion and normal above the lesion.
Like a patient with an acute T6 cord lesion may present with a band-like sensation at T6, but below this level (T7–S5), sensations will likely be impaired.
In subacute or chronic stages, a sensory level may become more obvious in which below the level lesion senstion will be equally effected ( absent or impaired)
For exam purposes, even if sensation appears normal in lower limbs, test up to the umbilicus (T10) or higher to ensure no sensory level is missed.
Key Dermatomal Landmarks:
Perianal area(saddle) S3–S5
Plantar foot S1
Back of calf and thigh: S1-S2
Dorsum of foot L5
Lateral leg L5
Medial leg/thigh L2–L4
Groin L1
Umbilicus T10
Epigastrium T6–T7
Ni***es T4
Shoulders C4–C5
Lateral upper arm C5
Thumb C6
Middle finger C7
Little finger C8
Medial forearm T1