Is This Complex Regional Pain Syndrome?

Patient Presentation
A 13-year-old female came to clinic with a 1 day history of a painful burning sensation in both feet. The previous day she and friends had a dance party and after returning home the feet began to be painful beginning on the right and then on the left. She and her parents noted some reddening and mild swelling. She took ibuprofen with some relief and she was able to sleep. The pain continued in the morning but the skin changes had subsided. She denied any trauma. She was somewhat hesitant to walk but said that she could despite the irritating burning/pain. The past medical history was positive for a broken right foot 4 months previous. After the cast was removed the patient developed pain, swelling and minor vascular changes and was diagnosed with complex regional pain syndrome that responded to physical therapy. The family history was positive for rheumatoid arthritis, Ehler-Danlos, and early myocardial infarction. The review of systems was otherwise negative.

The pertinent physical exam showed a well-appearing female who was cooperative and not in significant distress. Her right foot showed mild dorsal swelling and mottled discoloration of the sole. She complained of burning/pain from her toes to just above her ankle. The left foot had no swelling or skin changes but she complained of burning/pain on the dorsum of the foot. Lower extremities had full range of motion, normal strength and reflexes. There was no bruising or point tenderness. Femoral pulses were normal. She had no other skin changes and the rest of her examination was normal. As the physician was talking, she brought up that this could be trauma but most likely was a recurrence of the diagnosis of complex regional pain syndrome. The patient and mother both agreed that her current problems were exactly like her previous problems. They were confused though why both legs would be affected and the physician noted that this extension to other body parts does occur. The patient was to restart her previous physical therapy routine and to call if symptoms worsened or persisted more than 1-2 weeks. She had crutches at home if she needed them to help with mobility for brief time periods such as the end of the school day. Radiographs of the feet for possible fracture were also negative. At a health supervision visit 1 month later, she reported that the symptoms slowly improved over 2 weeks and that they hadn’t limited her activities very much. Physical examination at that time was normal.

Discussion
Musculoskeletal problems are a significant percentage of primary care visits (~20%), with pain being a common feature. Pain is a normal noxious sensation that is protective, but which has complex neurophysiological underpinnings and may have psychosocial overlays. Chronic musculoskeletal pain in children often begins orthopedic, rheumatologic, and oncologic evaluations. Chronic pain without an obvious biological cause can be frustrating for patients and clinicians alike to evaluate and treat.

Learning Point
Complex regional pain syndrome (CRPS) was previously known as reflex sympathetic dystrophy. It is usually seen in adults, with women more commonly than men experiencing the problem. It is seen in children usually starting in the tween and teenage years. There are often family histories of other chronic pain, neurological or psychiatric problems.

The exact cause is unknown but it is due to a disorder of pain neurophysiology and is not due to specific tissue damage. Although there often is a known precipitating event, such as acute obvious trauma, immobilization, repeated use, etc., the noxious sensations are out of proportion to this acute tissue damage and extend beyond the normal tissue healing time (i.e. the tissue at the time the patient is experiencing the noxious sensations is normal). Classic symptoms include: edema, vascular changes and increased pain in a body part. Other sensations include numbness, tingling, burning, and temperature changes. The body part affected is usually lower extremities but it may affect other areas. Trophic changes can also be seen.

Since it is a diagnosis of exclusion, appropriate evaluation for other possible causes should be made. Patients should be evaluated and treated with a multi-modal approach. Consultants may include orthopaedics, rheumatology, neurology, anesthesia, rehabilitation medicine, physical therapy and psychiatry/psychology. Getting the patient up and moving is critical to the treatment. Immobility makes patients worse. Physical therapy is key and may involve a number of treatments including mobilization, desensitization, hydrotherapy, massage, and other treatments. At the same time, pain control should be focused to allow physical therapy. Pain control can include oral analgesics, psychiatric/neurological medication, electrical stimulation, local or regional blocks, etc. Psychiatric/psychological evaluation and therapy for a primary or co-morbid mental health problem (i.e. conversion disorder, factitious disorder, anxiety, etc.) or a secondary problem in response to chronic pain and concomitant social withdrawal is vital to the overall patient management. Tricyclic antidepressants are often used as an adjunctive therapy. Most patients (80%) have resolution of symptoms by 6 months.

Questions for Further Discussion
1. What are the criteria for diagnosis of fibromyalgia?
2. How is fibromyalgia related to CRPS?

Related Cases

Disease: Complex Regional Pain Syndrome | Peripheral Nerve Disorders | Pain

Symptom/Presentation: Foot Pain

Specialty: Neurology / Neurosurgery | Orthopaedic Surgery and Sports Medicine | Physical Medicine and Rehabilitation / Physical Therapy | Psychiatry and Psychology | Rheumatology

Age: Teenager

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com, the National Guideline Clearinghouse and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for theses topic: Peripheral Nerve Disorders and Pain

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

Dangel T. Chronic pain management in children. Part II: Reflex sympathetic dystrophy. Paediatr Anaesth. 1998;8(2):105-12.

Small E. Chronic musculoskeletal pain in young athletes. Pediatr Clin North Am. 2002 Jun;49(3):655-62, vii.

Littlejohn GO. Reflex sympathetic dystrophy in adolescents: lessons for adults. Arthritis Rheum. 2004 Apr 15;51(2):151-3.

ACGME Competencies Highlighted by Case