R. Vincent Davis, DC, PT, DNBPM
Causalgia may be described as an uncommon pain syndrome characterized by posttraumatic pain most commonly affecting the upper or lower extremities. Clinically, the presenting pain is usually paroxysmally produced by local friction, or even air currents, which affect the nerve supply innervating that given region where the pain syndrome is symptomatically manifested. This pain phenomenon varies in its clinical presentation from immediately post-injury to several weeks later. The character of the injury may be as trivial as a sprain but any type of trauma may be etiological. Although the etiology is idiopathic, it is most often due to complete, or incomplete, laceration of the nerve, or plexus, involved.
The cardinal symptom is severe burning pain of paroxysmal character. There may be an intolerance to dryness in the area of pain and possible cutaneous coolness, color changes involving redness, or cyanosis, with glossiness, and edema. The pain is commonly exquisitely hyperalgesic. The symptoms may not present for several weeks following the etiological event, but gradually cutaneous symptoms indicative of vasodilation appear. Later, the skin may become cold, cyanotic, pale, diaphoretic, thin, and glossy with brittle and ridged nails. These cutaneous arteriovenous characteristics usually exist even in the presence of blood flow studies which show equality with the uninvolved extremity. These findings suggest that such nerve damage may affect surface vasodilatation without influencing larger deep vessels. Reduction, or complete elimination, of the pain by sympathetic block is diagnostic.
Since it has been shown clinically that the pain may spread to the opposite extremity, or to the cephalad, or caudal, cord, it is imperative to treat this clinical entity in a timely manner. If it went untreated, the probability is that it would reach a point in its progress where treatment would become unresponsive. Theoretically, the spread of this pain may take place in the internuncial pool.
Therapeutically, thermal agents in the form of hydrocollator packs, or silicone gel packs applied directly to the symptomatic region using a moist form of treatment to achieve the effect of convection, are desired for the vasoconstrictor type of pain. Application should be for 25 minutes p.r.n. with at least 10 minute intermissions between applications. Erythema ab igne must be avoided.
Moist cool packs in the form of ice packs, or silicone gel packs, may be applied to relieve the pain of the vasodilator type. Application should be for 10 minutes, directly to the symptomatic area, ensuring the absence of cyanotic increase due to percutaneous temperature effects. Pallor may be expected. The hyperemia and edema may be reduced by rest and elevation of the affected area.
Lidocaine (2.5 percent) phonophoresis over the area respective to the anatomical site of the perispinal sympathetic trunk on the ipsilateral side may be a helpful therapeutic aid in the treatment of the upper extremity. Application may be b.i.d., t.i.d., or p.r.n. pain. Treating the lower extremity would involve directing the cone of the ultrasonic beam at the sympathetic trunk between the first two pair of lumbar vertebrae with the same frequency of administration. Of course, phono-phoretic transfer is by pulsed waveform in this process.
In the event of the presence, or development, of trophic changes in the symptomatic area, referral to a neurosurgeon, or orthopedic surgeon, is mandatory to avoid the development of permanent trophic changes, or deformity. If conservative care is not providing for resolution of symptoms within two weeks, the patient should be referred, either for consult, or other treatment.
References
Davis RV: Therapeutic Modalities for the Clinical Health Sciences, 2nd ed. 1989. Library of Congress Card #TXU, 389-661
Griffin JE, Karselis TC: Physical Agents for Physical Therapists, 2nd ed. Springfield: Charles C. Thomas, 1982
Krupp, Chatton: Current Medical Diagnosis & Treatment. Lange Publishers, 1980.
Krusen, Kottke, Ellwood: Handbook of Physical Medicine & Rehabilitation, 2nd ed. Philadelphia: W.B. Saunders Company, 1982.
Schriber WA: A Manual of Electrotherapy, 4th ed. Philadelphia: Lea & Febiger Publishers, 1975.
Turek: Orthopedics, Their Principles and Application, 3rd ed. Lippincott.
Vincent Davis, DC, PT, DNBPME
Independence, Missouri
