- CONDITION CENTERS
Amputation dates back to prehistoric times, although survival rates must have been low. Among ancient civilizations, Egyptian mummies have been found with prosthetic limbs, suggesting improved techniques and postsurgical care. Interestingly, the first documented case of an above-knee amputation in Western cultures dates back to 1588.1 Today, amputation is a recognized subspecialty within many disciplines that requires a multidisciplinary treatment approach.
Annually, surgeons perform 133,735 amputations2 pursuant to 1 of 5 conditions:
? Extreme physical trauma in which bone, muscles, nerves, and tissue are destroyed and beyond salvage
? Peripheral vascular disease (PVD), stemming from diabetes or ischemic disease, which results in neuropathy, trophic ulcers, gangrene, and osteomyelitis
? Cancerous tumors
? Infections leading to vessel occlusion and extremity necrosis
? Congenital limb deficiency1,3
Amputations resulting from PVD are known as dysvascular amputations, the leading cause of amputation for people aged 50 and older. Patients requiring dysvascular amputation are either poor candidates for vascular reconstruction or patients in whom vascular reconstruction has failed. Lower-limb amputation, which includes any amputation from the toes to the hip joint, is the most common (Table 1).
Two amputation categories exist. In an open-flap amputation, the surgeon amputates the diseased area but does not close the wound. The skin is drawn back from the amputation site for several days, allowing direct access to the wound should the tissue become infected. In a closed-flap amputation, the skin flaps are sutured immediately.3 In performing lower-limb amputations, surgeons prefer to amputate below the knee, which is linked to improved outcomes. Knee-joint salvage enhances rehabilitation and requires less energy for ambulation.1
Maintaining skin integrity at the stump site is critical. The soft tissue enveloping the residual stump becomes the proprioceptive end organ for the interface between the limb and the prosthesis. Skin grafting may be required to ensure adequate healing and prosthesis functioning.
Prior to surgery, most patients are measured for their prostheses and receive counseling on living with an artificial limb. Prosthetic choice is individualized, ranging from externally fitted devices to patient-controlled motion robotics. Third-party insurers demand documentation on the medical necessity of prosthesis choice, partly because of cost and the lack of evidence-based guidelines.7 Osseointegration is the direct skeletal attachment of a prosthesis, a process that generally involves 2 surgeries.
Amputation is a straightforward surgical procedure; postsurgical care, however, presents numerous challenges. Hospital stays range from 5 to 14 days, and most wounds heal within 4 to 8 weeks.3
Immediately following surgery, experts recommend an epidural analgesia that is tapered downward concurrent with wound healing.8
In addition to standard wound dressing, a stump shrinker (a compressive wrapping to prevent swelling and help shape the limb) is generally applied to promote healing.9 Some surgeons also use a removable rigid dressing that protects the stump should the patient fall. These dressings are prefabricated and are usually plastic.
Residual pain at the amputation site is common, with 70% of amputees reporting postsurgical pain. Those with trauma-related amputations are 1.5 times more likely to experience residual pain than those with dysvascular amputations.10 Residual pain may be due to a poorly fitted prosthesis; therefore, patients need periodic evaluations by a prosthetist.
Wound healing may be severely compromised by the patient's underlying vascular disease that precipitated the amputation. Complications include edema, hemorrhage, hematoma, site infections, sepsis, soft-tissue debridement, necrosis of the skin flaps, and pneumonia. Anticoagulant agents prescribed postsurgically prevent venous thromboembolism.
Limb loss poses problems for pharmacotherapy dosing. Colangelo et al have published an article to help clinicians adjust for limb loss.11 It provides estimates of what proportion of body surface area is consumed by specific body parts, estimates that are also useful when treating patients with extensive burns. It appears that prescribers vary in the way they deal with amputation when drugs are dosed using body surface area or mg/kg. Some reduce the dose using the rule of nines, a burn formula used to estimate total body surface area (TBSA); each leg represents 18% TBSA, each arm 9%, the anterior and posterior trunk each 18%, and the head 9%.
Physical therapy ideally begins within 2 or 3 days after surgery, which generally includes gentle stretching.3 Depending on the amputation's severity, patients may be referred to an inpatient amputation rehabilitation program that is continued in an outpatient setting following discharge. Rehabilitation focuses on 2 treatment objectives: maximizing patients' abilities and facilitating patients' adjustment (Table 2).
Up to 51% of amputees experience phantom pain--the subjective pain experience in a limb that no longer exists--with 64% rating their pain as moderate to severe.13 Phantom limb pain is differentiated from residual pain at the stump site, which is believed to be the result of neuroma developing at the stump's nerve endings. Along with phantom pain, 76% of patients experience phantom limb sensations, generally in the form of tingling, burning, or itching.13 Once thought to be psychological, phantom sensations appear to result from brain nerve-circuitry changes. Over time, phantom pain tends to decrease or disappear altogether, but when phantom pain persists longer than 6 months, prognosis for total pain relief is poor.14 Up to 40% of patients experience some level of phantom pain 1 year following surgery.8
Researchers found that people with limb pain, gangrene, and infections prior to surgery are more likely to experience phantom pain. Phantom pain can be triggered by weather changes, a poorly fitted artificial limb, emotional stress, and fatigue.15 Patients are encouraged to maintain a pain diary to identify potential triggers.
Although the FDA has not approved any medications specifically for phantom pain, clinicians have found 2 medications useful in preventing it: calcitonin and ketamine. Managing phantom pain may involve trial and error. Other medications used to manage phantom pain include antidepressants, anticonvulsives, chlorpromazine, central nervous system depressants, opioids, clonidine, baclofen, and botulinum toxic type A. Electroconvulsive therapy, transcutaneous electrical nerve stimulation, hypnosis, heat applications, massage, biofeedback, and acupuncture may also relieve pain. Surgical interventions may be required in severe cases; these include spinal cord stimulation, intrathecal devices, and deep brain stimulation.14,15
Unlike 30 years ago, surgeons today first consider limb-salvage surgery in lieu of amputation, but unlike amputations, limb-salvage surgery is not considered lifesaving. Limb-salvage surgery usually involves bone grafts, tissue transplantation, and implanting internal devices.
In severe trauma cases, limb reattachment may be considered. Limb reconstruction is associated with a higher risk of complications, additional surgeries, and longer hospitalizations.7 Patients with successful limb-salvage surgery score significantly higher on quality-of-life measures than do amputees.16
Amputation is a life-defining surgery. Many practitioners view amputation as a treatment failure for the underlying condition that precipitated the surgery. Many patients also adopt this view, with many seeing themselves as physically incomplete, and up to 35% of amputees experience clinical depression.1 Factors influencing self-image include residual-limb comfort, prosthesis appearance, and ability to participate in social, recreational, and sexual activities. Patient's negative self-image, however, is not affected by residual-limb length.1
Patient education and support are key components in helping patients adjust to limb loss. Counseling must emphasize that amputation does not address the underlying PVD, and ongoing treatment and prevention are essential to avoid future amputations. Some patients fear mentioning phantom pain, believing others will see them as psychologically unsound. Clinicians should discuss this topic in advance and routinely evaluate amputees' of pain severity and treatment response. Counseling should also stress that the presence of pain does not necessarily mean worsening of conditions.
Observed increases in vascular amputations are attributed to increased prevalences in diabetes, tobacco use, hypertension, and hypercholesterolemia.2 Preventing or improving the clinical management of these risk factors will minimize amputation risk. Toward that objective, prevention efforts and treatment adherence are key.
1. Ertl J, Ertl W. Amputations of the lower extremity. Available at: www.emedicine.com/orthoped/topic9/htm. Accessed July 24, 2007.
2. Dillingham TR, Pezzin LE, MacKenzie EJ. Limb amputation and limb deficiency: epidemiology and recent trends in the United States. South Med J. 2002;95:875-883.
3. Society for Vascular Surgery. Amputation. Available at: www.vascularweb.org/_CONTRIBUTION_PAGES/Patient_Information/NorthPoint/Amputation.html. Accessed July 23, 2007.
4. Amputee Coalition of America, National Limb Loss Information Center. Amputation statistics by cause. Available at: www.amputee-coalition.org/fact_sheets/amp_stats_cause.html. Accessed July 23, 2007.
5. Aulivola B, Hile CN, Hamdan AD, et al. Major lower extremity amputation: outcome of a modern series. Arch Surg. 2004;139:395-399.
6. Feinglass J, Rucker-Whitaker C, Lindquist L, et al. Racial differences in primary and repeat lower extremity amputation: results from a multihospital study. J Vasc Surg. 2005;41:823-829.
7. Pasquina PF, Bryant PR, Huang ME, et al. Advances in amputee care. Arch Phys Med Rehabil. 2006;87(3 suppl 1):S34-43.
8. Jeffries GE. Pain management, post-amputation pain. Amputee Coalition of America Available at: www.amputee-coalition.org/inmotion/mar_apr_98/pain_mgt/page1.html. Accessed July 23, 2007.
9. Goldberg T. Postoperative management of lower extremity amputations. Phys Med Rehabil Clin N Am. 2006;17:173-180.
10. What you said about pain. Amputee Coalition of America. Available at: www.amputee-coalition.org/people-speak-out/what-you-said-about-pain.html. Accessed July 30, 2007.
11. Colangelo PM, Welch DW, Rich DS, Jeffrey LP. Two methods for estimating body surface area in adult amputees. Am J Hosp Pharm 1984; 41:2650-2655.
12. University of Virginia, Physical Medicine and Rehabilitation. Amputation. Available at: www.healthsystem.virginia.edu/uvahealth/adult_pmr/amput.cfm. Accessed July 23, 2007.
13. Kooijman CM, Dijkstra PU, Geertzen JH, et al. Phantom pain and phantom sensations in upper limb amputees: an epidemiological study. Pain. 2000;87:33-41.
14. WebMD. Pain management: phantom pain. Available at: www.webmd.com/pain-management/guide/phantom-limb-pain. Accessed July 23, 2007.
15. Mayo Foundation for Medical Education and Research. Phantom pain. Available at: www.mayoclinic.com/health/phantom-pain/DS00444. Accessed July 23, 2007.
16. Mason G, Aung L, Gall S, et al. Quality of life following amputation or limb salvage in patients with lower extremity sarcoma. J Clin Oncol. 2007;25(suppl 18S):19530. Available at: http://meeting.jco.org/cgi/content/abstract/25/18_suppl/19530. Accessed July 24, 2007.