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DictionarySeeamputationcongenital amputation
Congenital Amputation DefinitionCongenital amputation is the absence of a fetal limb or fetal part at birth. This condition may be the result of the constriction of fibrous bands within the membrane that surrounds the developing fetus (amniotic band syndrome) or the exposure to substances known to cause birth defects (teratogenic agents). Other factors, including genetics, may also play a role.DescriptionAn estimated one in 2000 babies are born with all or part of a limb missing, ranging from a missing part of a finger to the absence of both arms and both legs. Congenital amputation is the least common reason for amputation. However, there are occasional periods in history where the number of congenital amputations increased. For example, the thalidomide tragedy of the early 1960s occurred after pregnant mothers in western Europe were given a tranquilizer containing the drug. The result was a drastic increase in the number of babies born with deformed limbs. In this example, the birth defect usually presented itself as very small, deformed versions of normal limbs. More recently, birth defects as a result of radiation exposure near the site of the Chernobyl disaster in Russia have left numerous children with malformed or absent limbs.Causes and symptomsThe exact cause of congenital amputations is unknown. However, according to the March of Dimes, most birth defects have one or more genetic factors and one or more environmental factors. It is also known that most birth defects occur in the first three months of pregnancy, when the organs of the fetus are forming. Within these crucial first weeks, frequently prior to when a woman is aware of the pregnancy, the developing fetus is most susceptible to substances that can cause birth defects (teratogens). Exposure to teratogens can cause congenital amputation. In other cases, tight amniotic bands may constrict the developing fetus, preventing a limb from forming properly if at all. It is estimated that this amniotic band syndrome occurs in between one in 12,000 and one in 15,000 live births.An infant with congenital amputation may be missing an entire limb or just a portion of a limb. Congenital amputation resulting in the complete absence of a limb beyond a certain point (and leaving a stump) is called transverse deficiency or amelia. Longitudinal deficiencies occur when a specific part of a limb is missing; for example, when the fibula bone in the lower leg is missing, but the rest of the leg is intact. Phocomelia is the condition in which only a mid-portion of a limb is missing, as when the hands or feet are attached directly to the trunk.DiagnosisMany cases of congenital amputation are not diagnosed until the baby is born. Ultrasound examinations may reveal the absence of a limb in some developing fetuses, but routine ultrasounds may not pick up signs of more subtle defects. However, if a doctor suspects that the fetus is at risk for developing a limb deficiency (for example, if the mother has been exposed to radiation), a more detailed ultrasound examination may be performed.TreatmentSuccessful treatment of a child with congenital amputation involves an entire medical team, including a pediatrician, an orthopedist, a psychiatrist or psychologist, a prosthetist (an expert in making prosthetics, or artificial limbs), a social worker, and occupational and physical therapists. The accepted method of treatment is to fit the child early with a functional prosthesis because this leads to normal development and less wasting away (atrophy) of the muscles of the limbs present. However, some parents and physicians believe that the child should be allowed to learn to play and perform tasks without a prosthesis, if possible. When the child is older, he or she can be involved in the decision of whether or not to be fitted for a prosthesis.In the case of congenital amputation of the fingers, plastic surgery can sometimes be used to reconstruct the missing digits by transferring parts of the great and second toes to the hand. Some defects in the leg bones can be treated by removing the malformed bone, grafting bone from other parts of the child's body, and inserting a metal rod to strengthen the limb; this technique, however, is controversial as of the early 2000s.Recently, there have been cases in which physicians have detected amniotic band constriction interfering with limb development fairly early in its course. In 1997, doctors at the Florida Institute for Fetal Diagnosis and Therapy reported two cases in which minimally invasive surgery freed constricting amniotic bands and preserved the affected limbs.Alternative treatmentPrevention of birth defects begins with building the well-being of the mother before pregnancy. Prenatal care should be strong and educational so that the mother understands both her genetic risks and her environmental risks. Several disciplines in alternative therapy also recommend various supplements and vitamins that may reduce the chances of birth defects. If a surgical procedure is planned, naturopathic and homeopathic pre- and post-surgical therapies can speed recovery.PrognosisA congenital limb deficiency has a profound effect on the life of the child and parents. However, occupational therapy can help the child learn to accomplish many tasks. In addition, some experts believe that early fitting of a prosthesis will enhance acceptance of the prosthesis by the child and parents.PreventionStudies have suggested that a multivitamin including folic acid may reduce birth defects, including congenital abnormalities. Smoking, drinking alcohol, and eating a poor diet while pregnant may increase the risk of congenital abnormalities. Daily, heavy exposure to chemicals may be dangerous while pregnant.Key termsAmniotic band — An abnormal condition of fetal development in which fibrous bands of tissue develop out of the amniotic sac. The bands encircle and constrict parts of the baby's body, interfering with normal development and sometimes causing congenital amputation.Prosthesis — An artificial replacement for a missing part of the body.Teratogen — Any substance, agent, or process that interferes with normal prenatal development, causing the formation of one or more developmental abnormalities of the fetus.ResourcesBooksBeers, Mark H., MD, and Robert Berkow, MD, editors. "Musculoskeletal Abnormalities." Section 19, Chapter 261 In The Merck Manual of Diagnosis and Therapy. Whitehouse Station, NJ: Merck Research Laboratories, 2004.PeriodicalsDobbs, M. B., M. M. Rich, J. E. Gordon, et al. "Use of an Intramedullary Rod for Treatment of Congenital Pseudarthrosis of the Tibia. A Long-Term Follow-Up Study." Journal of Bone and Joint Surgery, American Volume 86-A (June 2004): 1186-1197.Garcia Julve G., and G. Martinez Villen. "The Multiple Monoblock Toe-to-Hand Transfer in Digital Reconstruction. A Report of Ten Cases." Journal of Hand Surgery 29 (June 2004): 222-229.OrganizationsInternational Child Amputee Network. 〈http://www.ampinfo.net/childamp.htm〉.March of Dimes Birth Defects Foundation. 1275 Mamaroneck Ave., White Plains, NY 10605. (914) 428-7100. resourcecenter@modimes.org. http://www.modimes.org.National Organization for Rare Disorders (NORD). 55 Kenosia Avenue, P. O. Box 1968, Danbury, CT 06813-1968. (203) 744-0100 or (800) 999-6673. Fax: (203) 798-2291. http://www.rarediseases.org.amputation [am″pu-ta´shun] the removal of a limb or other appendage or outgrowth of the body. The most common indication for amputation of an limb" >upper limb is severe trauma. Blood vessel disorders such as atherosclerosis, often secondary to diabetes mellitus, account for the greatest percentage of amputations of the limb" >lower limb. Other indications may include malignancy, infection, and gangrene. There are two general types of surgical procedure for amputation: (1) the closed or “flap” amputation and (2) the open or “guillotine” amputation. The latter is often required when infection is present and there is a need for free drainage from the operative site. A second surgical procedure involving stump (or residual limb) revision or closure is needed after the guillotine procedure. This is done only after the infection has been eliminated. Amputation. Bandaging on above-knee amputation stump. A, Use 6" elastic bandage. Enclose medial, distal end of stump. Apply pressure via bandage to end of stump. Use diagonal, not circular turns. B, Turn No. 3 must be high in groin and then turn made around waist to hold No. 3 in place. Do not pull hip into flexion. (A second 6" roll may be needed.) C, Turn No. 5 must be high in groin and a loop made around waist again. D, See diagram. E, Enclose lateral, distal end of stump. (A 4" roll may be needed.) Continue diagonal and figure-of-8 turns around stump. F, Continue turns to shape end of stump. (Courtesy of University of Washington Department of Prosthetics, from booklet Prosthetics-Orthotics.)Patient Care. The goal of patient care for the amputee is total rehabilitation with attainment of full function and normal active life. Such total rehabilitation is not always possible because of physical and mental limitations of the patient. It requires that the patient be physically and psychologically able to accept and adapt to a prosthesis and that each member of the health care team fulfill his or her responsibilities in preventing complications and in preparing the patient for optimum use of an artificial limb. Some patients, because of age or disease, do not have the necessary energy, muscular coordination, or mental capacity to undertake prosthetic training. Preoperative Care. Unless time is a factor, as in emergency cases demanding immediate surgery, the preoperative care of the potential amputee should include emotional and vocational aspects as well as the physical. If patients are fully involved in plans for their rehabilitation, understand what is expected of them, and know the regimen of exercise and skills they will need to develop, their chances of full recovery and achievement of independence will be greatly enhanced. Much emotional support and encouragement can be offered by other amputees who are successfully mastering their prosthesis and making progress toward their goal of total rehabilitation. Patients undergoing amputation will need help in dealing with the changes in body image as they adjust to the loss of a limb. They should be encouraged and given the opportunity to express feelings of anxiety, grief, anger, and depression, and given guidance in working toward a healthy acceptance of their handicap. In general, physical preparation of the patient undergoing surgical amputation includes measures to promote optimum health and well-being, to establish nutritional and fluid balances, and to increase muscular strength and endurance levels. A program of exercises may be started to help the patient develop skill in using an overhead trapeze, crutches, and a walker and transferring from wheelchair to bed.Postoperative Care. The residual limb is watched for hemorrhage, edema, infection, and ischemia. Some bleeding is not unusual but should rarely be more than a modest red stain on the dressing. Ischemia may be caused by a constricting dressing or the development of edema. Ischemia is recognized by the presence of excessive pain. Traction was formerly commonly used after guillotine amputations but is rarely used nowadays. Generally such stumps are closed by delayed primary closure on the fourth or fifth day after amputation to save time in the hospital and accelerate rehabilitation. Fitting of a prosthesis may be delayed or immediate depending on the condition of the patient and the reason for the amputation. Immediate fitting of a prosthesis involves the application of a rigid plastic dressing which serves to protect the stump and prevent edema. The dressing is similar to a cast and the patient will require care" >cast care. The temporary prosthetic device is applied at the time of surgery and includes a pylon and foot-ankle assembly. Early ambulation is a major advantage of immediate fitting of a prosthesis. Other benefits arise from the local compression exerted by the dressing. This serves to inhibit bleeding, to mold and help shrink the stump, and to reduce phantom sensations, pain, and contractures. Unfortunately, not all amputees are candidates for immediate fitting. The technique is not advised for amputations above the knee or above the elbow, for weak and debilitated patients, or for those who are mentally or emotionally unable to cooperate with efforts at rehabilitation. The procedure also requires the services of prosthetic experts. The more conventional, and probably more frequently chosen, technique of delayed prosthetic fitting requires special care of the stump and a gradual preparation of the patient for weight-bearing and ambulation. During the immediate postoperative period the stump dressings are changed or reinforced as ordered. The stump usually is wrapped with elastic bandages or covered with stump socks. The bandages are checked frequently for signs of bleeding and for slippage, which may lead to a tourniquet effect and the occlusion of blood supply. Exercises are started as soon as possible, regardless of the surgical approach, in order to strengthen the muscles and prevent contractures. The patient with amputation of an upper limb also may receive immediate or delayed fitting of a prosthesis. When the surgeon has chosen the delayed fitting technique, the patient requires stump care similar to that for the lower limb except that an upper limb stump is bandaged more loosely, especially when amputation was the result of trauma. Exercises are begun the day after surgery and within ten to fourteen days the patient is fitted with a temporary prosthesis.above-elbow (A-E) amputation amputation of the upper limb between the elbow and the shoulder.above-knee (A-K) amputation transfemoral amputation.below-elbow (B-E) amputation amputation of the upper limb between the wrist and the elbow.below-knee (B-K) amputation transtibial amputationChopart's amputation amputation of the foot, with the calcaneus, talus, and other parts of the tarsus being retained.cineplastic amputation kineplasty.closed amputation one in which flaps are made from skin and subcutaneous tissue and sutured over the bone end of the stump; called also flap amputation.congenital amputation absence of a limb at birth, attributed to constriction of the part by an encircling band during intrauterine development.amputation in contiguity amputation at a joint.amputation in continuity amputation of a limb elsewhere than at a joint.Dupuytren's amputation amputation of the limb" >upper limb at the shoulder joint.flap amputation closed amputation.flapless amputation guillotine amputation.Gritti-Stokes amputation amputation of the limb" >lower limb at the knee through condyles of the femur.guillotine amputation one in which the entire cross-section is left open (flapless) for dressing; called also flapless or open amputation.Hey's amputation amputation of the foot between the tarsus and metatarsus.interpelviabdominal amputation amputation of the limb" >lower limb with excision of the lateral portion of the pelvic girdle.interscapulothoracic amputation amputation of the limb" >upper limb with excision of the lateral portion of the shoulder girdle.kineplastic amputation kineplasty.Lisfranc's amputation amputation of the foot between the metatarsus and tarsus.major amputation amputation of the lower limb above the ankle or of the upper limb above the wrist.minor amputation amputation of a hand or foot, or of a part thereof.open amputation guillotine amputation.pulp amputation pulpotomy.racket amputation one in which there is a single longitudinal incision continuous below with a spiral incision on either side of the limb.root amputation excision of the root of a tooth; amputation of the root of a single-rooted tooth is called apicoectomy, and that of one root of a two-rooted mandibular tooth is hemisectomy. Called also radectomy and radiectomy.spontaneous amputation loss of a part without surgical intervention, as in leprosy, ainhum, and certain other conditions.Syme's amputation disarticulation of the foot with removal of both malleoli.transfemoral amputation amputation of the lower leg between the knee and the hip. Called also above-knee (A-K) amputation.transtibial amputation amputation of the lower leg between the ankle and the knee. Called also below-knee (B-K) amputationtraumatic amputation the sudden, accidental removal of a limb or appendage. A limb that is properly cared for may be reimplanted. It should be placed in a plastic bag, and if ice is available the bag containing the limb should be placed in a larger one that contains ice and water.Tripier's amputation amputation of the foot through the calcaneus.con·gen·i·tal am·pu·ta·tion [MIM*217100] amputation produced in utero; attributed to the pressure of constricting amniotic bands. See also: amputation (1). Synonym(s): amnionic amputation, intrauterine amputation, spontaneous amputation (1) con·gen·i·tal am·pu·ta·tion (kŏn-jen'i-tăl amp'yū-tā'shŭn) Amputation, usually a limb or part of a limb, produced in utero; usually attributed to the pressure of constricting amnionic bands. Synonym(s): amnionic amputation, birth amputation, intrauterine amputation, spontaneous amputation (1) . |