'Now You See It, Now You Do Not': Sensory-Motor Re-Education In Complex Regional Pain Syndrome

The patient with complex regional pain syndrome (CRPS) commonly describes a lack of ownership of their painful limb, poor definition of that body part and difficulty with localization of the limb when performing daily activities. These descriptions suggest that sensory input from the limb may be reduced leading to neglect of the limb and poor motor control. However, the cardinal symptom of CRPS is pain, commonly severe, which demands a high level of attention. Patients are highly protective of the painful region and hypervigilant to any potential threats to their affected limb. These seemingly conflicting behavioural responses and sensory descriptions are confusing for the patient and health-care professional. In recent years our understanding has greatly advanced on how altered sensory perception of a CRPS affected limb relates to changes in the central representation of that body part, and how this may interact with motor planning and autonomic function. Excitingly, this increased knowledge has directly informed clinical practice via a new evaluation of sensory-motor re-education techniques and the development of novel interventions to enhance sensory discrimination. We review the common sensory problems seen in CRPS, the mechanisms that may be behind these clinical symptoms, and how sensory, motor and autonomic systems interact. Therapies designed to enhance sensory discrimination and motor planning are discussed, supported by the results of a small case series undergoing sensory re-education for CRPS. The clinical protocol and two case studies are available as additional online material to illustrate how all of this is applied in practice.