Post-Amputation Pain and Phantom Limb Pain

What is Post-Amputation Pain?

Post-amputation pain is a poorly understood, yet common, condition that causes significant disability and can be difficult to treat. Amputation pain occurs in approximately 60 to 70% of patients, often arising weeks or months after a limb has been removed due to accident, injury, or disease. (1-2) Pain following an amputation may develop as either residual limb pain, phantom limb pain, or phantom limb sensation. (3)

•    Residual limb pain – pain or discomfort experienced in or at the stump of the amputated limb
•    Phantom limb pain – pain or discomfort felt to be coming from the missing limb or body part
•    Phantom limb sensation – sensation or perception of movement coming from the missing limb or body part

Post-amputation pain is a broad “catch-all” term, often used to refer to any of the aforementioned (without distinction) or even simply the general pain from the trauma of the amputation itself. The pain is often described as aching, throbbing, shooting, cramping, or burning. Non-painful sensations may include feelings of numbness, itching, paresthesias, twisting, pressure or even the perception of involuntary muscle movements in the residual limb at the amputation site. (4) These sensations may be generalized to the entire missing limb or localized to specific anatomical regions such as the fingers or toes.

What is Phantom Limb Pain?

Phantom limb pain is a type of post-amputation pain that can occur in any part of the body that no longer exists. Phantom pain has been described after mastectomy (phantom breast syndrome), eye removal and even after teeth extraction.

Phantom sensations may be mild at first and decline over time, yet remain to some degree indefinitely. Occasionally the discomfort will progress to severe pain that includes intermittent tremors and muscle spasms.

With time the sensation of a phantom body part can fade away. However in 50% of cases, especially upper limb phantoms, the missing arm seems to get progressively shorter until the patient is left with a sensation of the phantom hand alone, dangling from the stump. This symptom change is referred to as telescoping.

What Causes Post-Amputation Pain?

This type of pain is believed to stem from mixed signals that arise from the residual limb or brain. At the end of the stump, nerve fibers may grow a mass, or neuroma, that sends disordered signals to the brain. Meanwhile, in the brain, as other functions gradually take over the part of the brain that had been linked to the limb, painful sensations may arise.

Risk Factors for Developing Post-Amputation Pain

Relative risks are indicated as: Greater risks (top) > lesser risks (bottom)
•    Pre-amputation pain
•    Traumatic amputation > surgical amputation
•    Upper extremities > lower extremities
•    Amputation on both sides > amputation on only one side
•    Area of limb amputation closer to the body > area of limb amputation farther from the body
•    Older > younger e.g. children have lower incidence than adults
•    Female sex
•    Poor stump condition and stump pains are associated with phantom pain
•    Phantom sensations are associated with phantom pain
•    May be associated with catastrophizing and certain pain coping-strategies and beliefs

What is Stump Pain?

Stump pain is common in the early post-amputation period but diminishes as healing occurs. In 5 to 10% of patients, stump pain persists and can even get worse over time.

Stump pain and phantom pain are interconnected. For instance, lingering stump problems such as scars, neuromas (a post-amputation growth containing nervous-system tissue), or bone spurs can directly influence the intensity and duration of phantom pain. A significant association has been found between stump pain and phantom limb pain.

What Treatments are Available for Post-Amputation Pain?
Treatment can be challenging and should entail a multimodal and multidisciplinary approach that includes oral pain medications combined with rehabilitation therapy (i.e. biofeedback, mirror therapy, etc.).

Providers should remember to look for causes of stump pain and treat these since addressing the cause may reduce the incidence or severity of phantom pain.

Medications (5)
•    Acetaminophen and non-steroidal anti-inflammatory drugs (NSAIDs)
•    Opioids (narcotic pain medications)
•    Antidepressants
•    Anticonvulsants
•    Beta-blockers
•    Muscle relaxants

Physical Therapy and Behavioral Interventions (6)
•    Modalities (i.e. moist heat)
•    Ultrasound
•    Biofeedback
•    Relaxation techniques
•    Massage of the amputation area
•    TENS (transcutaneous electrical nerve stimulation) of the stump

Interventional Pain Management Treatments
•    Nerve blocks
•    Sympathetic nerve blocks
•    Neurolysis (i.e. pulsed radiofrequency ablation)
•    Intravenous infusion therapy (i.e. ketamine)

Neurostimulation

Spinal cord and peripheral nerve stimulation have been performed with varying results. For selected patients who have not obtained adequate relief with medical management, i.e. those who have intractable pain, spinal cord stimulation (SCS) can prove an effective intervention and should be considered. (7)

In 2015, dorsal root ganglion (DRG) stimulation in eight patients with amputation pain was reported to reduce phantom limb and residual limb pain by 53%; one individual reported a complete resolution of pain at 9 months. (8)

Potential newer neurostimulation treatments have been studied in recent years. For example, in 2015, pilot-study results were reported for high-frequency electrical nerve block in post-amputation pain. (9) A randomized clinical trial of repetitive transcranial magnetic stimulation in phantom limb pain was reported in 2016. (10)

References

1. Subedi B, Grossberg GT. Phantom Limb Pain: Mechanisms and Treatment Approaches. Pain Research and Treatment. 2011;2011:864605. doi:10.1155/2011/864605.

2. Chronic Conditions Team. 5 Ways to Deal with Chronic Limb Pain After Amputation. https://health.clevelandclinic.org/2015/09/5-ways-to-deal-with-phantom-limb-pain-after-amputation/. Accessed June 28, 2016.

3. Ephraim PL, Wegener ST, MacKenzie EJ, Dillingham TR, Pezzin LE. Phantom pain, residual limb pain, and back pain in amputees: results of a national survey. Arch Phys Med Rehabil. 2005;86(10):1910-1919.

4. HS Smith, I Lalaini, CE Argoff: Phantom Pain. In: Bonica JJ: The Management of Pain. 4Th ed. Philadelphia, Lea & Febiger; 2009: 331-338.

5. Anon. Managing Phantom Pain. http://www.amputee-coalition.org/limb-loss-resource-center/resources-for-pain-management/managing-phantom-pain/. Accessed June 28, 2016.

6. Anon. Phantom Limb Pain. http://www.webmd.com/pain-management/guide/phantom-limb-pain. Accessed June 28, 2016.

7. Viswanathan A, Phan PC, Burton AW. Use of spinal cord stimulation in the treatment of phantom limb pain: case series and review of the literature. Pain Pract. 2010 Sep-Oct;10(5):479-84. doi: 10.1111/j.1533-2500.2010.00374.x. Review.  PubMed PMID: 20412499. 

8. Eldabe S, Burger K, Moser H, et al. Dorsal Root Ganglion (DRG) Stimulation in the Treatment of Phantom Limb Pain (PLP). Neuromodulation. 2015;18(7):610-616; discussion 616-617.

9. Soin A, Shah NS, Fang ZP. High-frequency electrical nerve block for postamputation pain: a pilot study. Neuromodulation. 2015 Apr;18(3):197-205; discussion 205-6. doi: 10.1111/ner.12266. Epub 2015 Feb 5. PubMed PMID: 25655583.

10. Melville, N. Brain Stimulation Effective for Phantom Limb Pain. Medscape Multispecialty. Aug. 25, 2016. Accessed Aug. 28, 2016.


Reviewed Aug. 28, 2016
Corey W. Hunter, MD, FIPP
Patient Education Committee Member, International Neuromodulation Society, 2016
Executive Director
Ainsworth Institute of Pain Management
New York, New York, USA

Last Updated on Wednesday, October 18, 2017 03:59 PM