Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “AMPUTATION”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 901 records · Page 50Linked to original sources
PubMed2003

Amputation-induced activity of progenitor cells leads to rapid regeneration of olfactory tissue in lobsters.

Lobsters have a self-renewing olfactory system and, like many animals, continuously replace old or dying olfactory receptor neurons. In addition, lobsters are able to regenerate the peripheral olfactory system even after complete loss. The olfactory sensors in lobsters are located distally on a pair of antennules. These antennules are often damaged, but this has little impact on the lobster's sense of smell because damaged olfactory tissue is rapidly replaced. In this study, we investigated damage-induced regeneration of the olfactory system by measuring cell proliferation following controlled amputation. We show that amputation-induced regeneration occurs as a result of up-regulating the normal development of olfactory sensors. A unique feature of up-regulated development is the formation of patches of proliferating cells within the antennular epithelium. Epithelial patches were typically formed between 3 and 10 days postamputation on the amputated side. They were characterized by their: proximal position with respect to developing clusters of olfactory receptor neurons (ORNs); tendency to form two discrete patches within the borders of each existing annulus; cell size, which was approximately twice that of mature ORNs; and location within the ventral epithelium. The development of epithelial patches was immediately followed by proliferation of clusters of ORNs and associated glial cells, and the level of this proliferation increased significantly during the premolt stage of the lobster's molt cycle. These epithelial patches may represent populations of precursor cells, because they develop in response to amputation and immediately precede development of cell clusters composed of ORNs and glia. Possible regulatory signals controlling epithelial patch development are discussed.

Amputation, Surgical↗
PubMed2002

Outcomes after trans-tibial amputation: the relationship between quiet stance ability, strength of hip abductor muscles and gait.

BACKGROUND AND PURPOSE: Previous research regarding the symmetry of trans-tibial amputees has examined weight distribution and various gait parameters between prosthetic and sound limbs. However, to date, no known research has determined if asymmetry is present in the strength of the hip abductor muscles or if correlations exist between these categories of symmetry. The purpose of the present study was, therefore, to document asymmetry present in stance, strength and gait measures, and to determine the relationship between these variables. METHOD: Twenty-three elderly, unilateral trans-tibial amputees stood on two adjacent forceplates whilst the weight distribution and standard deviation (SD) of the anterior-posterior and the medio-lateral centre of pressure excursion (COPE) under each limb was recorded during four 40 s trials: quiet stance (QS), with eyes open and eyes closed; and even stance (ES), with eyes open and eyes closed. Gait measures (velocity, cadence, step and stride lengths, stance:swing ratio and period of double support) over 10 m of fast, yet safe walking and measures of the strength of hip abductor muscles were also obtained by use of a stride analyser and a dynamometer, respectively. RESULTS: No significant differences were found between QS and ES measures. However, significantly more weight was taken on the sound limb than on the amputated limb. Notably, more anterior-posterior movement occurred under the sound limb than the amputated limb, with this becoming more apparent with the eyes closed. Movement in the medio-lateral direction was found to be the same between sides. No differences in muscle strength or gait measures between limbs were demonstrated. However, strong hip abductor muscles were correlated with increased weight-bearing on the amputated limb, improved gait parameters and reduced medio-lateral COPE under the amputated limb. CONCLUSIONS: This research confirms the asymmetrical nature of amputee stance and demonstrates symmetry of strength and gait measures between limbs. The correlations between hip abductor muscle strength, weight distribution and gait measures illustrates the importance of pre- and post-operative training of these muscles.

Aged↗
PubMed1995

Evidence for transneuronal degeneration in the spinal cord in man: a quantitative investigation of neurons in the intermediate zone after long-term amputation of the unilateral upper arm.

Does transneuronal degeneration occur in the neurons of the spinal intermediate zone following degeneration of the anterior horn cells in man? To investigate this possibility, we carried out a quantitative examination of neurons in the cervical intermediate zone of a 56-year-old man who had suffered accidental amputation of the right upper arm 38 years prior to death. Recently, we reported that the cervical anterior horn cells of this patient were reduced in number not only on the amputation side but also on the spared side. The present study revealed that medium-sized neurons in the cervical intermediate zone, which were considered to be internuncial neurons, were decreased in number on both the amputation and the spared sides, but less so on the spared side. These findings indicate that retrograde transneuronal degeneration occurs in the internuncial neurons following degeneration of the anterior horn cells caused by amputation. Sequentially to this, degeneration of the commissural neurons in the intermediate zone secondary to that of the internuncial neurons may induce degeneration of the neurons in the intermediate zone and the anterior horn cells on the spared side.

Amputation, Traumatic↗
PubMed1993

A quantitative pathological investigation of the cervical cord, roots and ganglia after long-term amputation of the unilateral upper arm.

A pathological study was conducted on an autopsied patient who had undergone amputation of the right arm at the level of the shoulder 38 years prior to death. The numbers of anterior horn cell, spinal ganglion cells and myelinated fibers in the anterior and posterior spinal roots at the cervical segments were examined quantitatively and compared with those of age-matched control subjects. On the amputation side, anterior horn cells, spinal ganglion cells and large myelinated fibers of the anterior and posterior roots were decreased in number. In addition, on the spared side, the medium-sized neurons of Rexed's lamina IX were shrunken, or decreased in number, and the number of small- and medium-sized myelinated fibers in the anterior roots was decreased. These findings indicate that the long-term effects of axonal amputation induce retrograde degeneration of the anterior horn and spinal ganglion cells on the amputation side, resulting in atrophy and a decrease of medium-sized neurons in the anterior horn even on the contralateral, spared side.

Amputation, Traumatic↗
PubMed1985

Wound infection after lower extremity amputation because of ischemia.

The importance of postoperative wound infection in major amputations was elucidated by recording the organisms isolated in preoperatively infected gangrene and in postoperatively infected wounds of patients undergoing lower-limb amputations for ischemia. Sixty-four amputations were performed on 61 patients. The frequency of coexisting diabetes mellitus was 34%. Postoperative infections occurred in nearly two-thirds of the 19 cases of infected gangrene, as compared with less than one-third of cases of noninfected gangrene. The presence of diabetes mellitus did not significantly influence the infection rate. Preoperatively as well as postoperatively, the most frequently isolated bacterium was Staphylococcus aureus. Clostridium perfringens was cultured in four cases. Postoperative wound infection following lower-limb amputation for ischemia is the main reason for reamputation, especially in patients with infected gangrene.

Amputation, Surgical↗
PubMed1990

Impact of the presence of orthopedic hardware on technical performance of major amputations.

Metallic prostheses used for joint reconstruction or open reduction of fractures were discovered pre- or intraoperatively during the performance of six above-knee amputations. The prosthesis was found fortuitously before surgery in two cases on the basis of a surgical scar or radiograph of the leg. In four patients, discovery occurred intraoperatively, with adverse impact on the procedure in two cases: more proximal amputation level to allow hip nail removal was necessary in one case, and difficult transection of the prosthesis stem was encountered in one case. Orthopedic prostheses will be found with an increasing incidence in the population undergoing major amputation. As preparation for amputation, a careful review of the patient's history, a search for scars over the leg and hip, and survey radiographs of the leg must be obtained to prevent a surgical mishap caused by accidental discovery of a prosthesis.

Amputation, Surgical↗
PubMed1990

Amputation in elderly and high-risk vascular patients.

Fifty-eight patients underwent lower limb amputation for arterial disease over a 30-month period. Mean age of the patients was 72 years. Cardiopulmonary and metabolic risk factors were present in the majority of the patients. Postoperative one-year and three-year mortality rates were 24, 40, and 76%, respectively. Contralateral amputation was required in one-third of the patients after a mean period of eight months. Only younger and healthier patients returned to a meaningful social life after appropriate prosthetic fitting. In view of the high mortality and morbidity rates, above-knee amputation seems a better choice than below-knee amputation in these elderly and high-risk patients.

Activities of Daily Living↗
PubMed2006

[Inner amputation of an upper extremity with impaired cerebral perfusion and lethal outcome].

An inner amputation of the upper extremity is understood to be a rupture of the arm's vascular nerve bundle as well as the shoulder's and scapular's stabilizing muscles and fibrous joints without damage to the dermal soft tissue sheath. This injury is a rare and grave incident which mostly occurs within the scope of a high-energy trauma and in cases of polytraumatized patients in combination with additional life-threatening injuries. In the literature this is referred to by the terms scapulothoracic dissociation (SD) and closed forequarter amputation--the entity of SD was first described by Oreck et al. in 1984. Traction of the upper extremity leads to the rupture of the m. pectoralis major, m. pectoralis minor, the musculi rhomboidei, the m. levator scapulae, the m. latissimus dorsi as well as the m. trapezius. Furthermore the traction causes acromioclavicular or sternoclavicular bursting of the joints or a displaced clavicle fracture. Among the more than 50 cases depicted until now, 94% of the patients exhibit a neurological (plexus) and 80% a vascular lesion, thus corresponding to a genuine inner amputation. The prognosis for this injury is consistently poor: 10% of the patients die, in 52% an nonfunctional extremity remains, and in 21% a untimely amputation has to be performed. The observed complication of cerebral hypoperfusion caused by increasing pressure in the neck compartment, which ultimately leads to the death of the patient, has, as far as we know, not yet been specified and emphasizes the gravity and the magnitude as well as the necessity of rapid diagnosis and appropriate therapy of this infrequent injury.

Adult↗
PubMed2000

Decreasing incidence of major amputations in people with diabetes.

AIMS/HYPOTHESIS: To assess the results of the strategy used in avoiding major amputations in patients with diabetes mellitus. METHODS: A retrospective study for the years 1981 to 1995 in a central district hospital in Copenhagen with a catchment area population of about 178,000. RESULTS: There were 463 major leg amputations and the incidence decreased from 27.2 to 6.9/100,000 population (75%). The decrease in patients with Type I (insulin-dependent) diabetes mellitus was from 10.0 to 4.1 (59%) and in Type II (non-insulin-dependent) diabetes mellitus from 17.2 to 2.8/100,000 people (84%). Analysis showed that the diabetic population remained constant despite a considerable fall in the number of older people. During the study period infra-popliteal arterial bypass was introduced for the treatment of critical lower limb ischaemia and in diabetic patients the number of bypasses increased from zero to 13/100,000 population. The total number of revascularisation procedures in people with diabetes increased from 2.6 to 19.2/100,000 population. Moreover, a multidisciplinary diabetic foot clinic was established. CONCLUSION/INTERPRETATION: A 75% reduction in the incidence of major amputations coincided with a sevenfold increase in revascularization procedures and the establishment of a multidisciplinary diabetic foot clinic suggesting these measures are important in the prevention of diabetic leg amputations.

Adult↗
PubMed2000

Rapid functional plasticity of the somatosensory cortex after finger amputation.

Recent research indicates that areas of the primary somatosensory (SI) and primary motor cortex show massive cortical reorganization after amputation of the upper arm, forearm or fingers. Most of these studies were carried out months or several years after amputation. In the present study, we describe cortical reorganization of areas in the SI of a patient who underwent amputation of the traumatized middle and ring fingers of his right hand 10 days before cortical magnetic source imaging data were obtained. Somatosensory-evoked magnetic fields (SEF) to mechanical stimuli to the finger tips were recorded and single moving dipoles were calculated using a realistic volume conductor model. Results reveal that the dipoles representing the second and fifth fingers of the affected hand were closer together than the comparable dipoles of the unaffected hand. Our findings demonstrate that neural cell assemblies in SI which formerly represented the right middle and ring fingers of this amputee became reorganized and invaded by neighbouring cell assemblies of the index and little finger of the same hand. These results indicate that functional plasticity occurs within a period of 10 days after amputation.

Afferent Pathways↗
PubMed2001

Management of penile amputation injuries.

Penile amputation is an uncommon injury resulting from self-mutilation, felonious assault, or accidental trauma. Management requires resuscitation and stabilization of the patient with particular attention to underlying psychiatric illness. Amputated tissue can be preserved under hypothermic conditions in preparation for surgical replantation. Current replantation techniques rely on microsurgical approximation of the dorsal structures and cavernosal arteries with uniformly good results. Phallic replacement may be necessary when the amputated segment is lost. Microsurgical free forearm flap phalloplasty is the current mainstay of penile replacement surgery. Although urethral complications remain problematic, the results continue to be acceptable with regard to appearance and function. A unique subset of patients sustaining amputation injury is children. Both replantation and phallic construction have been successful in children and represent an alternative to gender reassignment.

Adult↗
PubMed1999

Historical evolution of limb amputation.

The amputation of a limb is one of the oldest surgical procedures. In the course of medical history operative techniques and surgical instruments have been improved continuously. As early as the first century Celsus described an amputation. A major step in the development of the operative technique was the introduction of an artery forceps by Paré during the sixteenth century. Nevertheless, due to a lack of analgesics and narcotics the operation had to take only a few minutes. Therefore the amputation was completed in one cut (i.e., detachment of the skin, muscles, and bone at the same level). This technique, known as "classic circular cut," was modified several times in the following period: to reduce suture tension Petit recommended that we transect the skin first and the muscles and bone more proximally ("two-stage circular cut," 1718), and Bromfield approved that the skin be cut first, the muscles more proximally and the bone most proximal ("three-stage circular cut," 1773). Lowdham (1679), Verduyn (1696), and Langenbeck (1810) changed the operative technique in that they used a soft-tissue flap to cover the bone without tension ("flap amputation").

Amputation, Surgical↗
PubMed2005

Healing of transmetatarsal amputation in the diabetic patient: is angiography predictive?

Transmetatarsal amputation (TMA) is a durable reconstruction in the diabetic patient with limited forefoot gangrene. However, predicting TMA healing remains difficult. Our goals were to (1) determine the success rate of TMA and (2) identify factors predictive of TMA healing, in particular arterial foot anatomy. A retrospective review of all diabetic patients undergoing TMA was done. Blood supply to the foot was classified as mostly anterior (anterior tibial and/or dorsalis pedis artery), mostly posterior (posterior tibial or plantar arteries), or equally distributed (both systems patent or peroneal runoff). Foot vessels were assigned runoff scores from 0 to 3 according to Society for Vascular Surgery/International Society for Cardiovascular Surgery (SVS/ISCVS) criteria. Forty-four TMAs in 29 men and 12 women were reviewed. Revascularization was done in 35 cases. In nine cases (20%), no bypass was deemed necessary (n = 7) or feasible (n = 2). Blood flow to the foot was deemed mostly anterior in 16 cases, mostly posterior in 17 cases, and equally distributed in 11. The TMA was left open in 19 cases and closed with staples or sutures in the rest. Limb salvage was achieved in 30 cases (68%) at a median follow-up of 48 weeks. Three of the four patients on dialysis required leg amputation (75%) vs. 11 of the 40 (27%) nondialysis patients (p = 0.05). When the TMA was left open, leg amputation was more likely (58%) than when closed primarily (12%) (p < 0.01). No angiographic factors were predictive of limb salvage. The need for revascularization was not associated with limb loss, although both patients with no feasible bypass option required below-knee amputation. TMA healing can be expected in a majority of diabetic patients after adequate revascularization but cannot be predicted by angiographic findings. Efforts should be made to achieve primary wound closure.

Aged↗
PubMed1999

Cardiac morbidity and operative mortality following lower-extremity amputation: the significance of multiple Eagle criteria.

The ability of the Eagle criteria (age >70 years, angina, diabetes, Q wave on EKG, history of congestive heart failure) to predict adverse cardiac events following major vascular surgery has previously been demonstrated. However, the utility of these criteria for lower-extremity amputation is not well established. To determine the value of the Eagle criteria for predicting cardiac morbidity and operative mortality following major lower-extremity amputation, we reviewed 214 consecutive procedures performed at two institutions over a 3-year period. Mean age was 62.7 years and 85% of the patients were male. Diabetes was the most frequent Eagle criterion (74%). The mean number of Eagle criteria was 1.6. Fifty-six percent of the amputations were below the knee, 24% were above the knee, and 20% were guillotine. On multivariate regression analysis, the presence of two or more Eagle criteria (16% vs. 4%, p = 0.04) and decompensated heart failure (39% vs. 7%, p = 0.003) were predictive of adverse cardiac events. The only predictor of postoperative mortality was the presence of two or more Eagle criteria (15% vs. 4%, p = 0.004). Our evaluation of the results of this study led us to conclude that patients requiring major lower-extremity amputation for major vascular disease who have multiple Eagle criteria or decompensated congestive heart failure are at high risk for adverse cardiac events and postoperative death. These findings should be used to guide perioperative cardiac evaluation and therapy.

Aged↗
PubMed1980

Use of Doppler pressure measurements in predicting success in amputation of the leg.

Fifty-five patients underwent amputation of the leg. Fifty-eight percent of the amputations were above-knee and 32 percent below-knee. Preoperative Doppler ankle blood pressure measurements and ankle/brachial ratios were compared and correlated with wound healing in patients with below-knee amputation. Statistical analysis documented that such measurements were significant in predicting wound healing. If blood pressure greater than 55 mm Hg at the knee, greater than 70 mm Hg at the incision site or greater than 70 mm Hg at the ankle or an ankle/brachial ratio of at least 0.3 is documented, satisfactory healing will follow amputation.

Aged↗
PubMed1982

Cause of wound complications in elderly patients with above-knee amputation.

Seventy-six above-knee amputations performed on elderly debilitated patients were reviewed. Fifty-one wounds healed without complications; 25 amputation wounds developed postoperative complications. The quality of the femoral pulse has a significant effect on wound healing after an above-knee amputation. Other significant conditions that appear to influence the frequency of wound complications are hypertension, a failed bypass procedure to the groin, and angiographic evidence of stenosis or occlusion of the common femoral or the profunda femoral artery. Multiple variable analysis suggests a beneficial effect of antibiotics in patients with a diminished or absent femoral pulse. Age, presence of cardiac disease, diabetes, associated diseases and the use of drains have no significant effect on the outcome. Before an above-knee amputation, patients with a diminished femoral pulse should undergo arteriography and perhaps reconstructive surgery. Primary hip disarticulation may be the initial procedure of choice in the presence of multiple risk factors.

Adult↗
PubMed1989

Prediction of below-knee amputation wound healing using noninvasive laser Doppler velocimetry.

Preoperative laser Doppler velocimetry (LDV) measurements of calf and brachial skin perfusion were performed in 29 patients prior to undergoing below-knee amputation; dual calf measurements on the anterior and posterior skin flaps were routinely obtained. Patients' ages ranged from 24 to 83 years; 16 had diabetes, 13 were smokers, 6 had hypertension, and 2 had known coronary artery disease. Anterior and posterior calf LDV values greater than or equal to 20 mV were associated with successful below-knee amputation wound healing in 25 of 26 patients; all 3 patients with either anterior or posterior calf LDV values less than 20 mV had below-knee amputations that failed to heal. Calculation of calf-brachial LDV indexes did not increase predictive accuracy compared to calf LDV measurements alone, although patients with wounds that failed to heal tended to have lower calf-brachial indexes. Preoperative noninvasive LDV may be used to aid in predicting the likelihood of successful healing after below-knee amputation.

Adult↗
PubMed1994

Lower limb amputation following injury: a survey of long-term functional outcome.

Although there have been significant advances in surgical methods of limb preservation and various injury scores produced to predict the outcome after severe lower limb injury, there is common belief amongst surgeons that patients rehabilitate rapidly and well after amputation. There is however little evidence in the literature supporting this view of functional outcome of amputation following injury. A subjective assessment of post-injury lower limb amputees implied that there was a similar functional outcome in above- and below-knee amputations. Furthermore, there was little functional difference between early and delayed amputations, the delayed group being more satisfied with the end result.

Adolescent↗