Chapter 29 - Postamputation Pain

Abstract

Amputation of a limb can lead to both painful and nonpainful sequelae, which occur in a majority of patients. 1.6 million Americans currently experience limb loss, with the prevalence expected to reach 3.6 million by 2050. Vascular disease (82%) and trauma (16%) are the most frequent causes. Phantom phenomena, including phantom limb pain, is thought to occur through interactions between altered peripheral, spinal, and supraspinal mechanisms. In contrast, residual limb pain, which often occurs with phantom phenomena, is associated with local pathologic processes, such as infection, heterotopic ossification, ischemia, or a neuroma of the transected nerve. The approach to a patient with postamputation pain involves a thorough evaluation of the affected limb and discussion with the patient’s therapists, prosthetists, and other providers. The most effective treatments are typically interdisciplinary in nature. Pharmacologic treatments have been more rigorously studied than other treatment options, but results are mixed, including the use of preventive analgesia to prevent phantom limb pain. Complementary therapies, such as mirror therapy, mental imagery, and noninvasive motor cortex stimulation may be beneficial. Psychological therapies are helpful in managing chronic pain in general but have not been well studied for postamputation pain. Interventional techniques such as neuroma injections, radiofrequency, and spinal cord stimulation are reportedly beneficial, but the evidence is limited to case series. Surgical therapies may include intracranial neurostimulation, peripheral neuromodulation, or resection of neuromas or heterotopic ossification. Management of postamputation pain remains challenging, but its importance will increase as patients live longer with limb loss.