-IBIS-1.5.0-
tx
nervous system
paresthesia
diagnoses
definition and etiology
definition:
An abnormal sensation in a body part, usually an extremity.
etiology:
Pressure or injury to a nerve can cause abnormal sensations. A common example is in the anterior scalene syndrome, where the chief symptoms are numbness and tingling of the arm, hand and fingers from muscle compression of the brachial plexus. As tension in the scalenes narrows the angle of where it attaches to the first rib, the neurovascular bundle becomes compressed. Other nerves (such as the sciatic) can cause symptoms in other areas of the body (such as the legs, feet, and toes). Other causes of paresthesias include vitamin deficiencies.
Paresthesias are also associated with some metabolic and infectious processes (e.g. herpes prodrome).
signs and symptoms
Symptoms often occur distal to the nerve involved.
Numbness.
Tingling: "pins and needles", sensation that the part has "fallen asleep".
Formication.
Weakness in the part.
Dull, aching pain may be present.
Hypersensitivity.
lab/orthopedic findings:
(+) for replication of the paresthesias (e.g. (+) Tinel's checking for carpal tunnel syndrome paresthesias.
X-ray/MRI/CT scan: Checking for tumor or other pathology that would cause pressure on the nerve (e.g. cervical rib or Pancoast tumor).
(+) vitamin deficiency: esp. B vitamins.
spinal fluid abnormalities, including increased cell count, increased protein, (+) serology in untreated patients.
course and prognosis
While the course is generally benign and the condition does not usually indicate a serious problem, a full work-up should be performed. The condition can be very debilitating and discomforting to the patient. Proper physiotherapy work, nutrition, exercises, and postural counseling can usually resolve the problem. Recurrences are common.
differential diagnosis
Many musculoskeletal conditions can cause paresthesias.
Tumors.
Vitamin deficiency.
Infectious process.
footnotes