Correspondence

Reflex Sympathetic Dystrophy Syndrome Following Air-Bag Inflation

N Engl J Med 1997; 337:574August 21, 1997

Article

To the Editor:

Reflex sympathetic dystrophy syndrome is commonly precipitated by trauma and is characterized by pain and swelling with signs of vasomotor instability in a distal extremity.1 We describe a case of air-bag–induced trauma followed by the reflex sympathetic dystrophy syndrome.

A 44-year-old woman had an accident while driving in December 1996. When the air bag inflated, her left and right hands, which were initially on the steering wheel, were pushed back against the window and the seat, respectively. Both carpometacarpal joints were dislocated, causing severe pain. After closed reduction, casts were applied for four weeks. Although the right hand returned to normal, pain, swelling, and stiffness persisted in the left hand, with involvement of the interphalangeal joints and wrist. This hand also had increased sweating and erythema. The patient had no shoulder pain or pain at other sites. Her symptoms persisted for three months and were unresponsive to nonsteroidal antiinflammatory drugs. X-ray films showed marked osteopenia of the left hand without fracture or dislocation. The results of laboratory tests, including the erythrocyte sedimentation rate, were normal. Reflex sympathetic dystrophy syndrome was diagnosed, and treatment with prednisone at a dose of 30 mg per day was begun, with gradual tapering of the dose along with aggressive physical and occupational therapy of the left hand. After four weeks, there was marked improvement, with almost full grip strength and no swelling or tenderness. In June 1997, after all medication and physical therapy had been discontinued, the patient reported decreased grip strength and pain in her forearm when she used her left hand, but no swelling. On examination, there was decreased flexion of the third through fifth proximal and distal interphalangeal joints due to contractures. The wrist was normal.

The reflex sympathetic dystrophy syndrome may occur in up to 5 percent of patients with traumatic injuries, and over 50 percent of cases are related to prior trauma.2 The trauma may cause wide-dynamic-range neurons in the spinal cord to become sensitized or hyperexcitable. Continuous pain can result from the tonic effects of the sympathetic nervous system on these neurons.3 Early recognition of the syndrome is important, since lack of treatment may lead to irreversible contracture. Treatment includes mobilization with intensive physical therapy and antiinflammatory analgesics. More recalcitrant cases may require treatment with corticosteroids or calcitonin.1 Occasionally, sympathetic-nerve block or surgical sympathectomy is needed.

Nimisha Shah, M.D.
Arthur Weinstein, M.D.
Westchester County Medical Center, Valhalla, NY 10595

3 References

1
Kozin F. Painful shoulder and the reflex sympathetic dystrophy syndrome. In: Koopman WJ, ed. Arthritis and allied conditions: a textbook of rheumatology. 13th ed. Vol. 2. Baltimore: Williams & Wilkins, 1997:1887-922.