Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Extremities”

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 253 records · Page 14Linked to original sources

Comparison of effects of vitamin E and wen-jing-tang (unkei-to), an herbal medicine, on peripheral blood flow in post-menopausal women with chilly sensation in the lower extremities: a randomized prospective study.

We examined the association between blood flow and chilly sensation in the lower extremities, comparing the changes in blood flow induced by the vitamin E and herbal therapy (Wen-jing-tang) in perimenopausal women with chilly sensation. One hundred sixty-one perimenopausal women aged 42-61 years (mean: 50.4 +/- 3.8 years) with chilly sensation in the lower extremities participated in the study. The participants were randomized for treatment with Wen-jing-tang or a vitamin E preparation containing 600 mg tocopherol nictinate per day for 8 weeks. Blood flow measurement was performed by laser Doppler fluxmetry to determine tissue under the jaw, in the middle finger, and in the third toe. Wen-jing-tang significantly increased the peripheral blood flow in the skin surface in the tiptoe (12.8 +/- 8.8, p = 0.0068) from basal levels (6.0 +/- 5.1), although no significant change was observed in the blood flow in fingertip or under the jaw during treatment. The rate of increase of blood flow in the skin surface of in the lower extremities was significantly higher in the Wen-jing-tang treating group (116.4 +/- 46.5%) than in the vitamin E group (39.8 +/- 21.3%) (p < 0.0001). When the effects of herbal treatment and vitamin E treatment were compared in the subjects with baseline upper extremity blood flow above the mean + 1.5 SD, mean blood flow through the upper extremities was found to have been significantly decreased after Wen-jing-tang treatment (from 57.7 +/- 4.8 to 43.1 +/- 4.2, p = 0.0277), whereas it remained unchanged after treatment with vitamin E. Classical monographs described Wen-jing-tang as being particularly useful in curing chilly sensation in lower extremities. The present study using a laser Doppler fluxmeter demonstrated that treatment with this herbal medicine significantly increased blood flow through the periphery of lower extremities in patients with chilly sensation. It also showed that this herbal medicine suppresses excessive blood flow through the upper half of the body and thus stimulates restoration of physiological distribution of blood flow throughout the entire body.

Adult↗

Incidence and distribution of lower extremity deep vein thrombosis in rehabilitation patients: implications for screening.

Patients admitted to in-patient rehabilitation programs have an increased risk for developing deep venous thrombosis (DVT). However, the utility of screening for lower extremity DVT using duplex ultrasound in this high-risk population is not well characterized. The purpose of this study is to identify whether or not screening lower-extremity duplex exams are indicated in this high-risk population. Screening lower extremity duplex exams were performed on all patients admitted to the rehabilitation center at Mt. Sinai Hospital over a 3-year period. Charts were reviewed for patient age, gender, diagnosis, date of screening and follow-up duplex exams, presence and location of venous thrombosis at each duplex exam, history of anticoagulation, and medical DVT prophylaxis. The presence of DVT at screening, the location of DVT along the lower extremity, and the outcome of calf DVT were analyzed in terms of gender, underlying diagnosis, and history of DVT prophylaxis. Lower extremity DVT was detected in 34% of patients. Twenty-three percent of patients had isolated calf vein thrombosis. Men were more likely than women to have DVT. Calf DVTs progressed in 3% of patients over an average follow-up of 2 weeks. The presence of DVT, its location along the lower extremity, and the outcome of calf vein DVT had no significant relationship to underlying diagnosis or history of prophylaxis. Screening duplex exams to detect lower extremity DVT in rehabilitation patients is useful. Screening altered management in 26% of patients, prompting either anticoagulation or repeat duplex exam.

Aged↗

[New possibilities of extremity revascularization in chronic ischemia: neoangiogenesis induced by exposure to high-intensive laser (an experimental study)].

The present work analyzes the results of an experimental study concerned with the treatment of chronic extremity ischemia. The experiments were carried out on 29 mongrel dogs. Chronic ischemia of the right hind extremity was simulated in 24 dogs (the superficial femoral artery was ligated just beneath the iliac artery and over its whole length as were all its collaterals). The significance of extremity ischemia was confirmed clinically, angiographically and morphologically. In the first group (19 dogs), the ischemized extremity underwent one month later concurrent tunneling of the femoral muscles and bone perforation in the diaphysis and metaphysis by exposure to high-intensive laser (Nd: YAG laser). The second group (5 dogs) served as control to study the response to ischemia. There were examined the area of laser-induced injury, the internal diameter of the capillaries and the diameter of muscle fibers, the specific area of the surface of blood vessels in the muscle and connective tissue. By the 60th day after exposure to laser an appreciable difference was recorded in the control and experimental groups: in the experimental group, angiography revealed a much greater number of vessels in the zone of the ligated femoral artery. Microscopy showed vascularized scars with muscle type arteries, active proliferation of endotheliocytes, formation of a new vascular bed. It is assumed that the tunneling of the ischemized extremity muscles concurrently with osteotrephination by high-intensive laser substantially restores blood flow in the distal segments of the ischemized extremities. Intensive development of the vascular network in the areas of the tunneling of the ischemized muscles of the hind extremities by exposure to high-intensive laser allows to compare this modality with universally used revascularization osteotrephination.

Angiography↗

[Application of bridged free latissimus dorsi musculo-cutaneous flap on the soft tissue defects in lower extremities].

OBJECTIVE: To evaluate the effect of bridged free latissimus dorsi musculo-cutaneous flap on repairing of soft tissue defect in the lower extremity. METHODS: Seven patients with extensive soft tissue defects in the lower extremities were enrolled in the clinical investigation. The defects were all repaired with bridged free latissimus dorsi musculo-cutaneous flaps. The condition of the blood vessels in the flaps and the healthy extremities was examined with ultrasound Doppler before the operation to assure the blood circulation of grafted flap. After debridement, the flap was designed in accordance with the size and the depth of the wound. Then the transplantation of the flaps were done. The operative indication and points for attention were summarized thereafter. RESULTS: All the 7 flaps survived. All patients recovered well with satisfactory function and external appearance, except flap reduction was done in 2 patients due to undue thickness of the flaps. Indications for operation: (1) Patients with anterior or posterior tibial artery injury in the injured lower extremity in which arterial transplantation was not possible to allow the free transplantation of a skin flap. (2) The injury was extensive and deep, with the injurious condition of the blood vessels indeterminable and no healthy artery could be found for anastomosis with a donor artery. (3) No vascular injury could be identified in the contralateral healthy extremity. Points for attention included that the blood supply of the flap to be transferred should be adequate, and the survival of the flap after division of the pedicle should be assured. The length of the flap to be transferred should be longer by 10% than the distance between the site of transplantation in the lower extremities and the donor area; and the donor area should be larger by 20% than the recipient area. The skin area of the flap to be transferred should be broad enough avoid tension so that there would be no pressure on the blood vessels. Pay attention to the blood supply of the flap after operation, and the recipient limb should be properly immobilized. CONCLUSION: The repair of extensive soft tissue defect in the lower extremity with bridged free latissimus dorsi musculo-cutaneous flap could be satisfactory. Proper wound management, broad flap, stable immobilization were the pivotal points for the success of the operation.

Adolescent↗

Self-reported somatization symptoms associated with risk for extreme alcohol use.

BACKGROUND: The high rates of alcohol use in the population, the increased general health care utilization associated with untreated alcohol problems, and the often diffuse nature of somatization symptoms led us to hypothesize that somatization symptoms might be associated with alcohol use. OBJECTIVE: To determine whether a relationship exists between somatization symptoms and alcohol use. DESIGN: Multivariable logistic regression models were used to analyze existing cross-sectional and 1-year longitudinal survey data from the National Institute of Mental Health Epidemiologic Catchment Area Program. SETTING: Community households. SUBJECTS: Probability sample. INTERVENTIONS: None. MAIN OUTCOME MEASURES: Prevalent and incident heavy or binge drinking ("extreme alcohol use"). These measures are part of the National Institute of Mental Health Epidemiologic Catchment Area Program public core data set that was collected without regard for specific hypotheses. RESULTS: After control for sex, age, and education, 13 self-reported somatization symptoms showed independent cross-sectional associations to prevalent extreme alcohol use. The greater the number of somatization symptoms, the greater the risk, up to a maximum increased odds ratio of 138 to 1, of having comorbid extreme alcohol use when reporting all 13 somatization symptoms in the model. A smaller set of items was associated with the risk for subsequent new onset of extreme alcohol use. CONCLUSIONS: Self-reported somatization symptoms could add to the detection of extreme alcohol use. In addition, primary care and other physicians should consider somatic complaints as possible indicators of concurrent and future risk for extreme alcohol use. Potential benefits of better detection of extreme alcohol use include supporting primary and secondary prevention efforts and reduced expenditures for the diagnostic workup of somatic complaints.

Alcoholism↗

Excimer laser treatment for high and extreme myopia. The Melbourne Excimer Laser and Research Group.

OBJECTIVE: The excimer laser allows the controlled ablation of corneal tissue to correct refractive error. We assessed the efficacy of excimer laser treatment for persons with high (spherical equivalent between -5 and -10 diopters) and extreme (spherical equivalent greater than -10D) myopia. METHODS: Patients were assessed 1, 3, and 6 months postoperatively. A VisX Twenty/Twenty laser was used. Visual acuity, refraction, corneal clarity, and adverse reactions were evaluated at each visit. RESULTS: Six month follow-up data were available for 194 high myopes and 53 extreme myopes. Postoperative healing was similar for the two groups. Six months postoperatively, 89.2% of high myopes and 49% of extreme myopes were within 2D of planned refraction. At 6 months, 28% of high myopes had an uncorrected visual acuity of 20/20 and 71% had an uncorrected visual acuity of 20/40. Of extreme myopes, 4% had an uncorrected visual acuity of 20/20 and 30% had an uncorrected visual acuity of 20/40. Significantly more corneal haze was observed in the extreme myopes. Loss of 2 or more lines of best corrected visual acuity was observed in 13% of high myopes and 13% of extreme myopes at 6 months. CONCLUSIONS: Excimer laser photorefractive keratectomy is an alternative means of treating high and extreme myopia and can cause a significant reduction in myopia. There is a need to gather further information as more patients are followed up for greater time.

Adult↗

The success of duplex ultrasonographic scanning in diagnosis of extremity vascular proximity trauma.

OBJECTIVE: To determine if duplex ultrasonographic scanning is diagnostically equivalent to arteriography and/or operative exploration in the diagnosis of extremity vascular proximity trauma. DESIGN: A prospective evaluation comparing duplex scanning with arteriography or operative exploration in 50 patients. Subsequently, duplex scanning was used alone for 175 extremity vascular proximity injuries, with other diagnostic methods used when injury was indicated on the duplex scan. SETTING: A busy urban trauma center. PATIENTS: Consecutive sample of 200 patients with 225 extremity injuries. SELECTION CRITERIA: Vascular proximity injury or diminished strength of the extremity pulse. MAIN OUTCOME MEASURES: The presence or absence of vascular proximity injury confirmed on angiography and/or operative exploration. RESULTS: Duplex scanning had 100% sensitivity and 100% specificity compared with arteriography and/or operative exploration in the first 50 cases. In the remaining 175 cases of extremity trauma, vascular injuries were diagnosed with duplex scanning alone. Duplex scanning detected 18 injuries, 17 of which were confirmed by correlation with arteriograms and/or operative exploration. One false-positive result--spasm of the superficial femoral artery--was found on arteriography. Seven unsuspected venous injuries were also diagnosed. CONCLUSIONS: Duplex scanning is a noninvasive, safe, effective method for the initial evaluation of potential extremity vascular proximity injury. It has replaced arteriography in the initial diagnosis of extremity vascular proximity trauma by our trauma service.

Angiography↗

Ability of ankle-brachial index to detect lower-extremity atherosclerotic disease progression.

BACKGROUND: Accurate determination of progression of lower-extremity arterial occlusive disease (LEAOD) is required for natural history studies and evaluation of therapies for atherosclerosis. OBJECTIVE: To determine if changes in the ankle-brachial index (ABI) correlated with progression of LEAOD as determined by arteriography or duplex scanning. DESIGN: In patients with prior suprainguinal or infrainguinal lower-extremity revascularization, progression of LEAOD in native arteries was determined by comparing a preoperative (baseline) arteriogram with late follow-up arteriography or duplex scanning. Superficial femoral and popliteal arteries were graded as having less than 50% stenosis, 50% to 99% stenosis, or as being occluded. Tibial arteries were graded as continuously patent or occluded. Operated and nonoperated extremities were included in the study. The baseline ABI was performed postoperatively and repeated at follow-up arteriography or duplex scanning. Progression of LEAOD by the ABI was defined as a decrease in the ABI of 0.15 or greater. Progression of LEAOD by imaging studies was defined as an increase in 1 category of stenosis. Extremities with suprasystolic pressures were excluded. SETTING: Tertiary vascular surgical service. EXTREMITIES AND PATIENTS: One hundred ninety-three extremities were studied in 114 patients during a mean follow-up of 3.3 years. RESULTS: Seventy-two lower extremities (37.3%) showed progression of atherosclerosis by late follow-up arteriography or duplex scanning. Using the imaging studies as the criterion standard, the ABI had 102 true negatives, 29 true positives, 42 false negatives, and 20 false positives (sensitivity, 41%; specificity, 84%; positive predictive value, 59%; negative predictive value, 71%; and accuracy, 68%) for determining the progression of LEAOD. CONCLUSIONS: The ABI is relatively insensitive in identifying the progression of LEAOD as demonstrated by the use of imaging studies. In studies of natural history or therapy for atherosclerosis, imaging studies should be used in preference to the ABI to evaluate the progression of LEAOD accurately.

Adult↗

The genome-scale metabolic extreme pathway structure in Haemophilus influenzae shows significant network redundancy.

Genome-scale metabolic networks can be characterized by a set of systemically independent and unique extreme pathways. These extreme pathways span a convex, high-dimensional space that circumscribes all potential steady-state flux distributions achievable by the defined metabolic network. Genome-scale extreme pathways associated with the production of non-essential amino acids in Haemophilus influenzae were computed. They offer valuable insight into the functioning of its metabolic network. Three key results were obtained. First, there were multiple internal flux maps corresponding to externally indistinguishable states. It was shown that there was an average of 37 internal states per unique exchange flux vector in H. influenzae when the network was used to produce a single amino acid while allowing carbon dioxide and acetate as carbon sinks. With the inclusion of succinate as an additional output, this ratio increased to 52, a 40% increase. Second, an analysis of the carbon fates illustrated that the extreme pathways were non-uniformly distributed across the carbon fate spectrum. In the detailed case study, 45% of the distinct carbon fate values associated with lysine production represented 85% of the extreme pathways. Third, this distribution fell between distinct systemic constraints. For lysine production, the carbon fate values that represented 85% of the pathways described above corresponded to only 2 distinct ratios of 1:1 and 4:1 between carbon dioxide and acetate. The present study analysed single outputs from one organism, and provides a start to genome-scale extreme pathways studies. These emergent system-level characterizations show the significance of metabolic extreme pathway analysis at the genome-scale.

Amino Acids↗

Rings and things on upper extremity radiographs of emergency patients.

Rings, intravenous lines, and other objects on the injured upper extremities of trauma patients are frequently overlooked by radiology and emergency department (ED) personnel. This can impair proper radiologic evaluation of the injured extremity as well as negatively affect the quality of the patient's treatment. A 1-week sample of radiographs of injured upper extremities from the ED of University Medical Center (UMC), Tucson, Arizona, showed that 20% of the studies (19 of 95) contained at least one object on the injured upper extremity, but only one radiology report (1.1%) mentioned such an object. A review of 2489 upper extremity ED radiology reports from January to June 2002 showed only 47 reports (1.9%) that mentioned the presence of an overlying object. It is important to educate radiology department and ED personnel to remove upper extremity jewelry and place necessary medical devices on noninjured extremities.

Journal Article↗

Late effects of radiotherapy for pediatric extremity sarcomas.

PURPOSE: To determine the long-term effects of radiotherapy (RT) in children treated for extremity sarcoma. PATIENTS AND METHODS: Between 1964 and 1997, 15 of 33 children treated with RT for extremity sarcomas at the University of Iowa have survived with a median follow-up was 20 years (range, 6-36 years). There were 10 boys and 5 girls with a median age of 13 years (range, 3.5-20 years) at the time of irradiation. The diagnosis was Ewing's sarcoma in 8 (53%), synovial sarcoma in 4 (27%), alveolar rhabdomyosarcoma in 2, and fibrosarcoma in 1. Location of primary tumor was lower extremity in 10 (67%) and upper extremity in 5 (33%). RT was given as the definitive therapy for 9 children (median dose, 55.8 Gy; range, 45-66 Gy) and as an adjuvant postoperative treatment in 6 (median, 63 Gy; range, 41.4-66.4 Gy). (60)Co was used in 6 (40%), 4 mV in 4, 6 mV in 2, and 250 kV photons in 2 patients; 1 child was treated with a combination of 12 and 15 MeV electrons for a Ewing's sarcoma of the distal femur. Another child had a 25 Gy intraoperative RT boost after 41.4 Gy conventional RT. Late effects to the muscle, soft tissue, and growing bone were assessed using the objective portion of the LENT-SOMA scale proposed by the Late Effects Consensus Conference. RESULTS: Late effects were seen in all patients and included atrophy in 12 (80%), fibrosis in 12 (80%), bone growth abnormalities in 10 (67%), impairment of mobility and extremity function in 6 (40%), edema in 3 (20%), and peripheral nerve injury in 2 (13%). Ten of 15 (67%) children had Grade 1 or 2 growing bone, muscle, soft tissue, or peripheral nerve complications. Two patients (13%) had a Grade 3 mobility and extremity function score and had moderate to severe limitation of movement. Two children (13%) required epiphysiodesis because of a shorter treated leg. The patient who received an intraoperative RT boost of 25 Gy developed sensory dysfunction of the ulnar nerve 11 years after RT. Another developed radial nerve palsy 3 years after marginal resection and postoperative RT and required tendon transfer repair. One patient had radiation-induced vasculitis with popliteal artery thrombosis 23 years after RT. Five (33%) developed a fracture of the irradiated bone at a median time of 8 years after RT (range: 9 months to 22.2 years); all had Ewing's sarcoma, and 3 of these patients were subsequently found to have a secondary bone cancer (osteosarcoma 2, malignant fibrous histiocytoma 1) in the RT field. One of these patients also developed breast cancer 26 years after lung RT for metastatic Ewing's sarcoma. Overall, 11 surgical procedures in 8 children were performed to correct a limb preservation treatment toxicity. CONCLUSIONS: Although most children treated with RT for a pediatric extremity sarcoma have minimal late toxicity by LENT-SOMA scale, approximately half required a surgical procedure to correct a late effect. A fracture in the irradiated bone may be the presenting sign or may precede a radiation-induced bone malignancy, as seen in 3 of the patients in this study.

Adolescent↗

Upper extremity fracture patterns following motor vehicle crashes differ for drivers and passengers.

PURPOSE: Injury patterns of occupants in motor vehicle crashes are changing, with upper extremity injury becoming more common in patients treated at trauma centres. Although not life threatening, upper extremity injuries may result in long-term disability, including chronic deformity, neurovascular compromise and degenerative arthritis. The purpose of this study was to compare upper extremity injury in drivers and passengers using the Crash Injury Research Engineering Network (CIREN) database. METHODS: CIREN data were used to compare upper extremity skeletal injury patterns and sources for drivers and passengers in frontal and side impacts. Occupant variables (age, gender, co-morbidity, avoidance maneuvers and restraint use) and crash variables (direction of impact, delta V and vehicle crush) were considered in the analysis. RESULTS: Only 24.8% of all occupants in the CIREN database had upper extremity injuries. One-half of upper extremity injuries to drivers were forearm fractures compared to one-third for passengers. Occupants in side impacts were more likely (OR=5.05) to have clavicle fractures, even while controlling for driver versus passenger status and safety belt use. Air bags were more likely to be a source of forearm fracture (OR=2.31) when controlling for driver versus passenger status, direction of force, sex and age compared to other sources. Only 10% of driver fractures with air bag deployment in frontal impacts were associated with air bag fling. CONCLUSIONS: This study found that drivers and passengers have different upper extremity injury patterns but the direction of impact also plays an important role.

Abbreviated Injury Scale↗

Prospective multicenter study of quality of life before and after lower extremity vein bypass in 1404 patients with critical limb ischemia.

BACKGROUND: Patients with critical limb ischemia (CLI) have multiple comorbidities and limited life spans. The ability of infrainguinal vein bypass to improve quality of life (QoL) in patients with CLI has therefore been questioned. Prospective preoperative and postoperative QoL data for patients undergoing lower extremity vein bypass for CLI are presented. METHODS: A validated, disease-specific QoL questionnaire (VascuQoL) with activity, symptom, pain, emotional, and social domains and responses scored 1 (lowest QoL) to 7 (best QoL) was administered before surgery and at 3 and 12 months after lower extremity vein bypass for CLI. Changes in QoL at 3 and 12 months after lower extremity vein bypass and multiple predetermined variables potentially influencing QoL after lower extremity vein bypass were analyzed to determine the effect of lower extremity vein bypass on QoL in CLI patients. RESULTS: A total of 1404 patients had lower extremity vein bypass for CLI at 83 centers in the United States and Canada as part of the PREVENT III clinical trial. Surveys were completed in 1296 patients at baseline, 862 patients at 3 months, and 732 patients at 12 months. The global QoL score (mean +/- SD) was 2.8 +/- 1.1 at baseline and was 4.7 +/- 1.4 and 5.1 +/- 1.4 at 3 and 12 months, respectively. Mean changes from baseline at 3 and 12 months were statistically significant (P < .0001). Improved QoL scores extended across all domains. Diabetes and the development of graft-related events were associated with decreased improvement in QoL scores, though the mean relative change from baseline remained positive. CONCLUSIONS: Patients with CLI have a low QoL at baseline that is improved at 3 and 12 months after lower extremity vein bypass. QoL improvements are lower in diabetic patients and those who develop graft-related events. Successful revascularization can be expected to improve QoL in patients with CLI, with benefits that are sustained to at least 1 year.

Aged↗

Elevated C-reactive protein levels are associated with postoperative events in patients undergoing lower extremity vein bypass surgery.

OBJECTIVES: Inflammatory markers such as high-sensitivity C-reactive protein (hsCRP) are associated with an increased risk of cardiovascular events and with the severity of peripheral arterial disease. The effects of inflammation on the development of vein graft disease remain speculative. We hypothesized that high levels of inflammatory markers would identify patients at increased risk for adverse events (graft failure, major cardiovascular events) after lower extremity bypass surgery. METHODS: Patients (n = 91) scheduled to undergo lower extremity bypass using autogenous vein were enrolled into a prospective study at two institutions. Exclusion criteria included the presence of major infection. A baseline plasma sample was obtained on the morning of lower extremity bypass. Biomarkers for inflammation included hsCRP, fibrinogen, and serum amyloid A (SAA). Values between patients with and without critical limb ischemia were compared. Proportions of events among dichotomized populations (upper limit of normal of each laboratory assay) were compared by log-rank test. RESULTS: Of the patients undergoing lower extremity bypass, 69% were men, 53% were diabetic, 81% were smokers, and their mean ankle-brachial index was 0.51 +/- 0.19. The indication for lower extremity bypass was critical limb ischemia in 55%. There were no perioperative deaths and two early graft occlusions. During a mean follow-up of 342 days (range, 36-694 days) there were four deaths, 27 graft-related events, and 10 other cardiovascular events. No relationships were found between events and demographics, comorbidities, baseline ankle-brachial index, or statin use. High-sensitivity CRP (P = .005), fibrinogen (P < .001), and SAA (P = .0001) levels were associated with critical limb ischemia at presentation. Among patients with an elevated hsCRP (>5 mg/L) immediately before surgery, major postoperative vascular events occurred in 60% (21/35), compared with a 32% (18/56) rate in those with a baseline CRP <5 mg/L (P = .004, log-rank test). On multivariable analysis, only elevated hsCRP correlated with adverse graft-related or cardiovascular events (P = .018). CONCLUSIONS: The inflammatory biomarkers of hsCRP, fibrinogen, and SAA correlate with peripheral arterial disease severity at presentation in patients undergoing lower extremity bypass. Patients with elevated hsCRP are at increased risk for postoperative vascular events, most of which are related to the vein graft. These findings suggest a potential relationship between inflammation and outcomes after lower extremity vein bypass surgery.

Arterial Occlusive Diseases↗

Effect of multilevel sequential stenosis on lower extremity arterial duplex scanning.

BACKGROUND: The sensitivity of lower extremity arterial duplex scanning in detecting a > 50% stenosis may be decreased in extremities with multilevel sequential stenosis. PATIENTS AND METHODS: The results of lower extremity arterial duplex scanning of the common femoral, upper and lower superficial femoral, above- and below-knee popliteal arteries, and tibioperoneal trunk in 80 extremities of 44 patients were compared to those of arteriography. Thirty-one arterial segments in 27 extremities had a > 50% stenosis. The stenoses were categorized as first order (first or only stenotic segment in the extremity, n = 23) and second order (stenosis occurring distal to a > 50% stenosis, n = 4, or occlusion, n = 4). RESULTS: The sensitivity, specificity, and positive predictive values of duplex scan detection of a > 50% arterial stenosis or occlusion were 86%, 96%, and 67% for the common femoral artery; 95%, 98%, and 95% for the upper superficial femoral artery; 97%, 90%, and 88%, for the lower superficial femoral artery; 84%, 90%, and 87% for the above-knee popliteal artery; 47%, 98%, and 90% for the below-knee popliteal artery; and 25%, 100%, and 100% for the tibioperoneal trunk. Duplex scanning detected 18 (78%) of the 23 first-order stenoses compared to only 1 (13%) of the 8 second-order stenoses in limbs with multilevel sequential disease (P < 0.01). The peak systolic velocity at the stenotic site was significantly higher for first-order (mean +/- SD 168 +/- 54 cm/s) compared to second-order (38 +/- 13 cm/s) stenoses (P < 0.00002). CONCLUSIONS: Duplex scanning was highly sensitive in detecting lower extremity first-order stenoses. Low peak systolic velocities at second-order stenoses of limbs with multilevel sequential disease significantly decreased the sensitivity of duplex scanning.

Arterial Occlusive Diseases↗

Testing apparatus and experimental procedure for position specific normalization of electromyographic measurements of distal upper extremity musculature.

OBJECTIVE: An apparatus and procedure are described to determine position specific normalization coefficients for surface EMG of upper extremity musculature. STUDY DESIGN: Thirty-nine subjects were tested three times. Repeatability of EMG measurements across test sessions was determined by computing intraclass correlation coefficients. Two-way analysis of variance was used to test upper extremity position dependent differences in EMG measurements. BACKGROUND: EMG measurements are susceptible to error from skin movement and muscle length changes, both of which may occur when upper extremity positions vary. Normalization of the EMG signal without consideration for such positional influences may lead to erroneous conclusions regarding muscle activation during functional tasks. METHOD: An apparatus was designed that allowed subjects to perform three repetitions of maximum elbow flexion, forearm pronation, wrist extension, and wrist flexion with the forearm in neutral and pronated positions. Surface EMG was sampled from eight muscles. Mean EMG on maximum voluntary contraction was computed, and resting EMG was subtracted to obtain EMG normalization coefficients. RESULTS: Upper extremity position affected the EMG normalization coefficient for biceps brachii, which was lower in the pronated position, and extensor carpi radialis, which was higher in the pronated position (P<0.00625). CONCLUSIONS: The apparatus accommodates various combined positions of the elbow, forearm and wrist. The normalization procedure is efficient for testing subjects who are being observed during functional tasks. Only two muscles were affected by upper extremity position, but group trends were not always consistent with individual behavior. This method would ensure the use of appropriate EMG normalization coefficients regardless of individual variation. RELEVANCE: This method is effective for normalizing EMG signals using task specific upper extremity positions. It may be used to test isometric exertions of distal upper extremity musculature for clinical and research purposes.

Adult↗

Efficacy of color flow duplex imaging for proximal upper extremity venous outflow obstruction in hemodialysis patients.

PURPOSE: The efficacy of color flow duplex imaging (CFDI) in detecting proximal upper extremity venous outflow obstruction in hemodialysis patients was compared with that of traditional contrast venography. METHODS: From 1993 through 1997, all hemodialysis patients who were evaluated for upper extremity venous outflow obstruction of the axillary, subclavian, or brachiocephalic veins with both CFDI and venography were identified. Medical history, hemodialysis access procedures, and indications for imaging were reviewed. The diagnostic accuracy of CFDI was compared with that of venography for proximal venous outflow obstruction, including focal stricture, partial obstruction, or complete occlusion. RESULTS: Sixty upper extremities in 42 hemodialysis patients were imaged with both CFDI and venography. Previous ipsilateral intravenous dialysis catheters had been present in 33 (55%) of the extremities imaged; current catheters were present in 16 (27%) of the extremities imaged; and 28 (67%) of the extremities imaged had a current ipsilateral arteriovenous (AV) shunt. Five (8%) of the 60 duplex scans were nondiagnostic because of artifact from intravenous dialysis catheters (3) or incomplete visualization of the subclavian or brachiocephalic veins (2) and were excluded from further analysis. In the remaining 55 duplex scans, proximal venous outflow obstruction was found in 18 (33%), compared with 21 (38%) identified by means of venography (P = not significant [NS]). Overall sensitivity, specificity, positive predictive value, and negative predictive value for CFDI were 81%, 97%, 94%, and 89%, respectively. CONCLUSION: CFDI is a reliable means of detecting proximal upper extremity venous outflow obstruction and should replace contrast venography as the initial imaging study in hemodialysis patients.

Adult↗

Cephalometric analysis with digital storage phosphor images: extreme low-exposure images with and without postprocessing noise reduction.

This study evaluated extreme exposure reduction in cephalography with monitor-displayed DICOM (Digital Imaging and Communication in Medicine, Rosslyn, Va) images. The purposes were to investigate to what extent exposure can be reduced without losing diagnostic information for tracing analysis, whether postprocessing noise reduction could benefit localization of anatomic landmarks in extreme low-exposure images, and the quality of the images. Three images (optimal, extreme low exposure, and noise-reduced extreme low exposure) were obtained from 24 volunteers. Three orthodontists traced 18 landmarks and subjectively judged the quality of the images. Sixteen of the landmarks were well identified on the extreme low-exposure images when they were compared with the optimal images. Apex inferius and apex superius were not well identified. The evaluation of image quality on a visual analogue scale showed that the optimal images were given the highest scores, extreme low-exposure images with postprocessing noise reduction the second highest scores, and extreme low-exposure images the lowest scores. Monitor-based tracing analysis on storage phosphor cephalographic images with a 94% exposure reduction, compared with conventional exposure, can be performed with only 2 of 18 landmarks not well identified. The landmarks were better identified on the low-exposure images with standard postprocessing than on the images with post-processing noise reduction, although the subjective evaluation of the image quality indicated the opposite.

Adult↗