A 12-year-old, 53-kg girl presented to the ER with excruciating (10/10) left ankle pain. The patient said, “Please don’t touch my left ankle and foot. It is so painful that I can’t put any weight or wear socks anymore!” Three months earlier, the patient was in soccer practice when another player collided into her. She felt pain immediately in her left lower leg, followed by ankle swelling. Left ankle fracture was diagnosed and surgically repaired by open reduction and internal fixation under general anesthesia.
Resolution of the Case
A left-sided sciatic peripheral nerve catheter (PNC) with ultrasound guidance was placed under general anesthesia, after confirming dorsi and plantar flexion with loss of stimulation at 0.4 mA.
The sciatic PNC was bolused with 20 mL of 0.15% ropivacaine. In the PACU, the patient reported extensive numbness corresponding to the distribution of the sciatic nerve (sensory block) and inability to flex and extend her ankle (motor block). The sciatic catheter was infused with 0.08% ropivacaine at 4 mL per hour. The next day, the patient was able to fully participate in her physical therapy without motor block, while maintaining good analgesia control with pain scores of 1 of 10. After five days of catheter infusion, the sciatic PNC was removed, the pain score returned only to 3 of 10, and the patient was able to successfully carry out her activities of daily living (ADL). Four days later, the patient was discharged home and restarted school activities. She continued outpatient physical therapy, occupational therapy and psychological counseling to learn coping mechanisms. Four years later, the patient had resumed a normal teenage life with no residual chronic pain.
CRPS is a chronic pain condition typically affecting the limbs after an injury. CRPS is a diagnosis of exclusion, which is often delayed in children.1 Before establishing a diagnosis of CRPS, it is important to rule out other acute medical conditions, such as osteomyelitis, infection, new fractures, compartment syndrome and other surgical complications. Radiological examinations, electromyography and nerve conduction studies can be helpful in delineating underlying medical or surgical problems.
History must include a detailed social history to identify significant emotional stressors at home or school.2 Physical examination must focus on specific signs and symptoms of skin color, hair, and sensory or motor changes. Pathophysiology for CRPS is often multifactorial; it may be caused by neurogenic inflammation, nociceptive sensitization, autonomic dysfunction or maladaptive neuroplasticity.1
CRPS type I occurs without significant nerve injury, whereas type II is often associated with nerve injury.
Diagnosis uses the Budapest clinical criteria3:
The Budapest criteria do not specifically address pediatric CRPS. In children, CRPS is more frequent in white adolescent girls affecting lower extremities after minor trauma. Approximately 90% of cases are diagnosed in girls at a median age of 13 years. In adults, the median age of diagnosis is 43, and the upper extremities are more frequently affected, mostly after severe traumatic events.1,3,4 The prognosis is more favorable in children.3
The optimal treatment in pediatric CRPS patients is early interdisciplinary intervention for functional rehabilitation.1 The end point of therapy is to restore ADL and functional independence. Occupational therapy aims to improve the functional use of the affected extremity, active range of motion, coordination, ADL and school participation. Individualized physical therapy increases the functional use of the affected extremity while improving weight-bearing, active range of motion and muscular strength. Psychosocial treatment/cognitive-behavioral therapy helps patients cope with depression, anxiety and obsessive-compulsive disorder while learning cognitive coping skills, relaxation techniques and deep breathing exercises.3,5
Admission to an inpatient rehabilitation center allows patients to be isolated from the school environment and parental involvement, thus removing any potential pain trigger.3 Inpatient rehabilitation is usually the most effective way to interrupt the pain and disability cycle and shorten recovery time. Inpatient rehabilitation, usually a three-week program, maximizes the potential for successful control of the environment (e.g., activities, diet, sleep) and for the interdisciplinary structure to adhere to a common treatment philosophy.3 Inpatient rehabilitation is followed by a stepwise transition to outpatient care and the home environment to follow up on the patient’s functional level, sleep, nutrition, social factors, emotional factors, family dynamics and academic ADL as they relate to pain.
Medications, which are not used for curative purposes but to reduce symptoms to allow full participation in therapy, may include tricyclic antidepressants, acetaminophen, nonsteroidal anti-inflammatory drugs, gabapentin, tramadol, capsaicin patch, benzodiazepines, corticosteroids and, ultimately, opioids.4,6
Invasi ve procedures include sympathetic nerve blocks, tunneled epidural catheters and PNCs.7 In contrast to adults, the response to treatment, particularly early exercise therapy with behavioral management, achieves nearly 97% remission in the pediatric population.1 Complete recovery without any residual disability is common in children.1
- CRPS is a diagnosis of exclusion; all underlying medical and surgical problems need to be ruled out.
- Use a careful history and physical examination and the Budapest criteria to diagnose patients with CRPS.
- The epidemiology, diagnosis, treatment and prognosis are vastly different in the pediatric versus the adult population.
- Multidisciplinary therapy and early interviews are important in pediatric pain rehabilitation, as prognosis and relapse are usually favorable in this population.