CRPS I, formerly known as reflex sympathetic dystrophy, consists of continuous pain (allodynia or hyperalgesia) in part of an extremity after trauma, including fractures.
However, the pain does not correspond to the distribution of a single peripheral nerve. The pain is worse with movement and is associated with sympathetic hyperactivity. The patients often complain of cool, clammy skin which later becomes pale, cold, stiff and atrophied. This process often occurs within weeks of trauma, which may be mild.
Treatment of CRPS I
Mobility, physiotherapy, rehabilitation and sympathetic nerve blocks.
CRPS II, formerly known as causalgia, consists of burning pain in the distribution of a partially damaged peripheral nerve (most commonly median, ulnar or sciatic).
Pain may occur within a month of injury and may radiate beyond the nerve’s distribution. The condition results from abnormal sweat and vasomotor sympathetic efferent pathways, possibly due to abnormal connections between efferent sympathetic fibres and somatic sensory fibres at the injury site. The skin is classically cold, moist and swollen, becoming atrophic later.
Treatment of CRPS II
Has traditionally been sympathetic nerve blocks.