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In 62 patients 72 repeated multiple operations on the arteries of lower extremities were carried out. In 7 cases both lower extremities had to be amputated at mid-femoral level. The time from the first vascular operations to the amputation of the other extremity ranged from 6 months and 16 days to 8 years and 30 days (mean 5 years).
BACKGROUND: The most common malignancy in the USA is basal cell carcinoma. It is most prevalent on the head and neck, but can occur elsewhere. We sought to determine the frequency of basal cell carcinomas arising on the lower extremities, as well as the gender of affected patients, the histologic subtype, and the specific sites of involvement. METHODS: We reviewed cases submitted to the Vanderbilt Dermatopathology Service between 1994 and 1997 which were diagnosed as basal cell carcinoma. A subset of 150 cases which arose on the lower extremities and a control group of 150 cases which arose at other anatomic sites were studied further. RESULTS: A significantly greater number of basal cell carcinomas of the lower extremities arose in women, were of the superficial subtype, and were found below the knee; 59% of basal cell carcinomas in both sexes arose on the right limb. CONCLUSION: Basal cell carcinomas of the lower extremities occur more often in women in the USA and are of the superficial subtype. This may be due to differing patterns of dress and exposure to the sun.
We report a 62-year-old man with ballism confined to the right leg, so-called monoballism. He was admitted to our hospital complaining of gait disturbance due to violent involuntary movements in the right lower extremity which had developed seven days before. He had a ten-years' history of hypertension and at age 57 had been diagnosed as having asymptomatic multiple cerebral infarcts. Until admission, he was taking antiplatelet drugs for the purpose of preventing thrombotic stroke. On neurological examination, he showed mild impairment of higher brain function, Horner's sign in the left eye, and typical ballism in the right lower extremity. Involuntary movements were never observed in the face and the other extremities. Surface electromyography also showed reciprocal burst discharges at about 1 Hz related to the ballistic movements in the right lower extremity. CT scan revealed a high density lesion surrounded by a low density in the left subthalamic area. MRI examination demonstrated a dumbbell shaped hemorrhage extending from the left subthalamic nucleus to the dorsomedial nucleus of the ipsilateral thalamus. Adding to the hemorrhage, many ischemic lesions were observed in the bilateral basal ganglia and thalamus including the left pallidum. The causal end of the hemorrhage apparently located in the anterior dorsomedial portion of the subthalamic nucleus. There were few reports concerning monoballism, especially monoballism limited to the lower extremity. Recent researches indicate that a subthalamic lesion reduces the excitatory control from the subthalamus to the internal segment of the globus pallidus, which leads to a disinhibition of the thalamus and gives rise to ballism.(ABSTRACT TRUNCATED AT 250 WORDS)
PURPOSE: The purpose of this study was to prospectively evaluate the treatment of patients with occluded lower extremity bypass grafts, comparing surgical revascularization with catheter-directed thrombolysis. MATERIALS AND METHODS: One hundred twenty-four patients (68% male and 32% female) with lower limb bypass graft occlusion (46 autogenous and 78 prosthetic) were prospectively randomized to surgery (n = 46) or intra-arterial catheter-directed thrombolysis (n = 78) with recombinant tissue plasminogen activator (rt-PA) 0.1 mg/kg/h modified to 0.05 mg/kg/h for up to 12 hours, or urokinase (UK) 250,000 U bolus followed by 4,000 U/min for 4 hours, then 2,000 U/min for up to 36 hours. A composite clinical outcome including death, amputation, ongoing/recurrent ischemia, and major morbidity was analyzed on an intent-to-treat basis at 30 days and 1 year. RESULTS: The average duration of graft occlusion was 34.0 days, with 58 (48%) presenting with acute ischemia (0 to 14 days) and 64 (52%) with chronic ischemia (> 14 days). Thirty-nine percent randomized to lysis failed catheter placement and required surgical revascularization. Overall, there was a better composite clinical outcome at 30 days (P = 0.023) and 1 year (P = 0.04) in the surgical group compared with lysis, due predominately to a reduction in ongoing/recurrent ischemia, most notable in autogenous grafts. However, following successful catheter placement, patency was restored by lysis in 84%, and 42% had a major reduction in their planned operation. One-year results of successful lysis compared favorably with the best surgical procedure, which was new graft placement. Acutely ischemic patients (0 to 14 days) randomized to lysis demonstrated a trend toward a lower major amputation rate at 30 days (P = 0.074) and significantly at 1 year (P = 0.026) compared with surgical patients, while those with > 14 days ischemia showed no difference in limb salvage but higher ongoing/recurrent ischemia in lytic patients (P < 0.001). Patients with occluded prosthetic grafts had greater major morbidity than did those with occluded autogenous grafts (P < 0.02). CONCLUSIONS: Proper catheter positioning currently limits the potential of catheter-directed thrombolysis for lower extremity bypass graft occlusion. Patients with graft occlusion > 14 days have a significantly better outcome when treated surgically, with a new bypass being the best surgical option. However, in patients with acute limb ischemia (< 14 days) successful thrombolysis of occluded lower extremity bypass grafts improves limb salvage and reduces the magnitude of the planned surgical procedure. Patients with occluded prosthetic grafts suffer more major morbid events compared with occluded autogenous grafts.
A retrospective investigation was undertaken to determine the prevalence of tennis-related lower extremity injuries in the San Francisco Bay area. A total of 376 participants at various Bay area tennis clubs completed a questionnaire before registering for tournament play. The results obtained from the survey indicate that 91.2% of this population had an injury to the lower extremity. A discussion of the etiology and mechanism of the various lower extremity injuries is presented.
Fourteen patients with chronic venous insufficiency (CVI) of the lower extremities, class 0-4 according to the CEAP (1995) were examined for microcirculation (MC) and effect of detralex, using biomicroscopy of the conjunctival vessels and capillaroscopy of the nail matrix, with detailed computed morphometry. In 7 patients, CVI was associated with truncal arterial hypertension and in 5 with type 2 diabetes mellitus. It has been established that in CVI patients, there were remarkable disorders of MC and regional circulation. In addition to regression of the clinical manifestations of CVI, administration of detralex given in courses to 12 patients noticeably refined both regional circulation in the lower extremities and systemic MC, marked by abatement of perivascular edema, an increase in the number of the functioning microvessels and flow acceleration in them. Also, there was marked the lowering of intramuscular red blood cell aggregation.
OBJECTIVE: Class 6 chronic venous stasis is associated with abnormal venous hemodynamics and ulceration. Ulcers primarily occur over bones and tendon prominences but very rarely over muscular compartments. We hypothesized that the anatomical distribution of venous stasis ulcers in the lower extremity is related to a lower density of venous valves. METHODS: The venous vasculature of six normal human legs was cast with resin, and their microvenous valvular anatomy was examined. Skin samples were obtained from the skin overlying the 1) Achilles' tendon, 2) anterior tibia, 3) medial malleolus, 4) lateral malleolus, 5) dorsal surface of the foot, 6) planta pedis, 7) dorsal aspect of the great toe; and from the skin regions overlying the 8) gastrocnemius, 9) tibialis anterior, and 10) peroneus muscles. The valvular and venous densities were determined in a scanning electron microscope, normalized to the size of specimens, and the valvular index was calculated. Analysis of variance with Bonferroni t-test was used to compare the valvular index between the regions. RESULTS: Venous valves were observed in all tissue regions. The diameter of veins with valves ranged from 18 microm to 803 microm. The valvular index for regions overlying bones/tendons (i.e., regions 1-7) was significantly higher versus those overlying muscular regions (i.e., regions 8-10) (p < 0.05). The valvular index was not different (p = 0.51) when regions 1 and 2 (where ulcers almost never occur) were compared to regions 3, 4, 5, 6, and 7 (where ulcers frequently occur); nor were there differences between the vascular indexes of regions overlying muscle. The largest venous valves were observed in the plantar region, and the smallest-sized ones were present in the peroneal region. CONCLUSIONS: This study shows that the density of venous valves is actually higher in regions of the human lower extremity overlying bones and tendons, where venous stasis ulcers are common, than those overlying muscular areas, where ulcers are rarely seen. Thus, valvular quantity alone cannot account for the higher clinical incidence of ulceration. It is likely that muscular pumping and/or valvular quality are important factors in preventing the development of venous stasis and ulceration in the lower extremity.
BACKGROUND: Cognitive decline and poor physical function are risk factors for disability in old age and may occur more often in subjects with the apolipoprotein E epsilon4 (ApoE-epsilon4) allele. The objective of this study was to investigate the joint effect of ApoE-epsilon4 and structural changes detected on MRI brain scans on cognitive decline and lower-extremity function. METHODS: Brain MRI (1.5 T), neuropsychological tests, and lower-extremity physical function tests were administered to World War II male veteran twins ages 69 to 80. Quantification of MRI scans used a previously published algorithm to segment brain images into total cerebral brain (TCB), cerebrospinal fluid (CSF), and white-matter hyperintensity (WMH) volumes. A short battery of physical performance tests was used to assess lower-extremity function. Ten-year changes in performance on the Mini-Mental State Exam (MMSE), the Benton Visual Retention Test (BVRT), and the Digit Symbol Substitution (DSS) test were used to assess cognitive decline. RESULTS: For the sample as a whole, the comparison of subjects by median split of total cerebral brain volume found that those with brain volumes below the median performed worse on tests of gait and balance (p < .01) and experienced greater cognitive decline on the MMSE and BVRT cognitive test batteries (both p < .01). In addition, subjects with WMH volumes above the median had poor performance on the standing balance tasks and experienced greater decline on the DSS test (p < .01). Stratified analyses revealed that the joint effect of radiological findings and the ApoE-epsilon4 allele on cognitive decline and lower-extremity function was often greater than that expected from the separate effects combined. CONCLUSIONS: We conclude that radiological findings in conjunction with ApoE-epsilon4 may single out a group at higher risk for dementia. We speculate that the observed interaction effect may be due to increased susceptibility to brain injury or impaired repair mechanisms in subjects with ApoE-epsilon4.
OBJECTIVES: Standard lower extremity contrast-enhanced magnetic resonance angiography (LE-CEMRA) with single injection bolus-chase methods on the basis of a single pelvis timing run can be accurate for depicting most vascular occlusive lesions but may fall short of catheter-based angiography when imaging tibial and pedal vessels. Magnetic resonance angiography techniques with a second contrast timing bolus and separate acquisitions for the calves and the pelvis greatly improve reliability and reduce venous contamination to levels that may render conventional angiography obsolete. METHODS: From July to December 2001, 60 consecutive patients underwent LE-CEMRA of the calves with separate stepping-table acquisitions of the pelvis and thighs. Forty-five (75%) had complete or partial angiographic correlation during an endoluminal intervention or operative completion study. Lower extremity vessels were divided into anatomic segments (aortoiliac, femoropopliteal, tibial-pedal) for review. Three blinded observers assessed magnetic resonance source partitions, maximum-intensity projections, and volume-rendered images. Disease per segment was graded from insignificant (<20%) to occluded (100%) in 10% increments. Segments were also scored for venous contamination (scale, 0 to 3) and diagnostic quality (scale, 1 to 5). Digital subtraction angiograms were assessed similarly but separately. RESULTS: The combination dual-timing/dual-injection technique had an overall sensitivity, specificity, and accuracy of 99%, 97%, and 98%. Venous contamination and artifact were virtually eliminated with combined technique LE-CEMRA. Diagnostic quality of calf and foot vessels was significantly superior to conventional bolus-chase magnetic resonance techniques (P <.01). CONCLUSION: Hybrid dual-acquisition LE-CEMRA allows complete timing specification that consistently produces high-quality, artifact-free images of the calf and pedal vessels. These techniques may be accurate enough to replace conventional digital subtraction angiogram for evaluation of lower extremity vascular occlusive disease.
BACKGROUND: Patients with diabetes mellitus, particularly those with poor glucose control, commonly experience various medical complications related to the disease (eg, renal impairment, decreased peripheral vascular circulation, suppressed immune function). Infections of the lower extremities can range from superficial cellulitis to ulcerative, deep soft-tissue infections to osteomyelitis that necessitates some degree of amputation. OBJECTIVE: This study compared the efficacy, tolerability, and cost differences associated with the use of metronidazole plus ceftriaxone (MTZ/CTX) given once daily with those of ticarcillin/clavulanate potassium (T/C) given every 6 hours in hospitalized older males with diabetic lower-extremity infections. METHODS: This prospective, open-label study was conducted at a Veterans Affairs Medical Center. Male patients with diabetes and a lower-extremity infection were randomized to receive MTZ/CTX 1 g once daily or T/C 3.1 g every 6 hours. Treatment success was determined at 96 hours or on discontinuation of antibiotic. Success was measured in terms of body temperature <38.3 degrees C (100.6 degrees F), normalization of the finger-stick blood sugar concentration, improvement in wound staging, or a white blood cell count <10,000 cells/mm3. Medication acquisition costs per treatment arm were calculated and compared. RESULTS: Seventy patients were enrolled in the study (36 MTZ/CTX, 34 T/C). The study population had a mean (SD) age of 63.8 (10.8) years, a duration of diabetes of 12.4 (9.1) years, 0.5 (0.7) diabetes-related comorbidities, and an initial creatinine clearance of 67.1 (26.0) mL/min. There were no significant differences between groups at randomization. At 96 hours, treatment success was achieved in 31 (86%) patients in the MTZ/CTX group, compared with 28 (82%) patients in the T/C group (P=NS). Twenty-six patients were considered successfully treated on the final day of therapy in both the MTZ/CTX group (72%) and the T/C group (76%) (P=NS). There were no significant differences in primary or secondary measures of success between the 2 groups. No single or multiple baseline factors predicted treatment success or failure. No patient experienced adverse events considered related to study medication. MTZ/CTX was associated with savings of $61.06 per hospital admission, or $2198.05 for all patients who received this combination. CONCLUSION: In this population of older males, once-daily MTZ/CTX was as well tolerated and effective as T/C in the treatment of diabetic lower-extremity infections and was associated with reduced institutional costs.
Lower extremity paresis poses significant disability to chronic stroke survivors. Unlike for the upper extremity, cortical adaptations in networks controlling the paretic leg have not been characterized after stroke. Here, the hypotheses are that brain activation associated with unilateral knee movement in chronic stroke survivors is abnormal, depends on lesion location, and is related to walking ability. Functional magnetic resonance imaging of unilateral knee movement was obtained in 31 patients 26.9 months (mean, IQ range: 11.3-68.1) after stroke and in 10 age-matched healthy controls. Strokes were stratified according to lesion location. Locomotor disability (30 ft walking speed) did not differ between patient groups (9 cortical, 12 subcortical, 10 brainstem lesions). Significant differences in brain activation as measured by voxel counts in 10 regions of interest were found between controls and patients with brainstem (P = 0.006) and cortical strokes (P = 0.002), and between subcortical and cortical patients (P = 0.026). Statistical parametric mapping of data per group revealed similar activation patterns in subcortical patients and controls with recruitment of contralateral primary motor cortex (M1), supplementary motor area (SMA), and bilateral somatosensory area 2 (S2). Cortical recruitment was reduced in brainstem and cortical stroke. Better walking was associated with lesser contralateral sensorimotor cortex activation in brainstem, but stronger recruitment of ipsilateral sensorimotor and bilateral somatosensory cortices in subcortical and cortical patients, respectively. A post hoc comparison of brainstem patients with and without mirror movements (50%) revealed lesser recruitment of ipsilateral cerebellum in the latter. Subcortical patients with mirror movements (58%) showed lesser bilateral sensorimotor cortex activation. No cortical patient had mirror movements. The data reveal adaptations in networks controlling unilateral paretic knee movement in chronic stroke survivors. These adaptations depend on lesion location and seem to have functional relevance for locomotion.
BACKGROUND: Lower extremity arterial disease (LEAD) is common and underdiagnosed in patients with diabetes mellitus and is associated with higher total mortality. METHODS: We compared the accuracy of pulse oximetry, the ankle-brachial index (ABI), and the combination of the two to diagnose LEAD in consecutive outpatients with type 2 diabetes who had no symptoms of LEAD, in a primary care setting. Exclusions were age younger than 40 years, known LEAD, or typical symptoms of LEAD. Fifty-seven patients were enrolled. All patients had (1) ABI measurement; (2) pulse oximetry to measure Sao2 of their index fingers and big toes in the supine position and at 12-in elevation; and (3) Doppler waveform analysis of the lower extremity arteries. The ABI was considered abnormal if it was less than 0.9. Pulse oximetry of the toes was considered abnormal if the Sao2 was more than 2% lower from the finger or on 12-in elevation of the foot. The combination was considered positive if either the ABI or pulse oximetry was positive for LEAD and negative if both were negative. We defined LEAD as monophasic waveforms on waveform analysis. RESULTS: Of our patients, 31% had LEAD. Pulse oximetry had a sensitivity of 77% (95% confidence interval [CI], 61%-88%) and a specificity of 97% (95% CI, 91%-99%); ABI had a sensitivity of 63% (95% CI, 46%-77%) and a specificity of 97% (95% CI, 91%-99%). Positive likelihood ratios were 30 (95% CI, 7.6-121) for pulse oximetry and 24.8 (95% CI, 6.2-99.8) for ABI; negative likelihood ratios were 0.23 (95% CI, 0.12-0.43) for pulse oximetry and 0.38 (95% CI, 0.25-0.59) for ABI. For the combination, sensitivity was 86% (95% CI, 71%-94%) and specificity was 92% (95% CI, 84%-96%). CONCLUSIONS: Pulse oximetry of the toes seems as accurate as ABI to screen for LEAD in patients with type 2 diabetes. Combination of the two tests increases sensitivity.
OBJECTIVE: To assess the prognostic value of motor evoked potentials (MEPs) in the lower extremity with respect to motor recovery and functional recovery in stroke patients. DESIGN: Cohort study. SETTING: The department of neurology at a university hospital. PARTICIPANTS: Thirty-eight acute-stroke patients with complete paralysis (paralysis subgroup) or severe paresis (paresis subgroup) of the lower extremity. MEPs of the vastus medialis and the tibialis anterior muscles were recorded between days 3 and 10 after stroke onset. INTERVENTIONS: Not applicable. Main outcome measures A separate proximal leg motor score (maximum, 16 points) and crural motor score (maximum, 2 points) were defined within the lower-limb subset of the original Fugl-Meyer Motor Assessment to evaluate the motor performance at regular intervals until 6 months after stroke. The transfer item of the Barthel Index and the Functional Ambulation Categories scores were used to assess transfer and walking ability. RESULTS: For the paralysis subgroup (n=30), the follow-up was complete in 27 patients (2 patients died, 1 patient underwent above-knee amputation). At 26 weeks, 20 patients experienced proximal motor recovery (mean score +/- standard deviation, 11.70+/-4.48), and 12 of them also showed crural motor recovery (mean score, 1.40+/-.51). Nine patients (33%) could perform an independent transfer safely, and 7 (26%) had learned to walk independently. Analysis revealed significant relationships for tibialis anterior muscle MEPs and motor recovery of crural leg muscles (odds ratio [OR]=18.00; 95% confidence interval [CI], 1.31-894.40), but not for vastus medialis muscle MEPs and proximal motor recovery (OR=6.00; 95% CI,.53-303.00). We found no association between vastus medialis muscle MEPs and recovery of ambulation. However, tibialis anterior muscle MEPs seemed to provide a test with prognostic value for the ability to perform independent transfers (OR=17.50; 95% CI, 1.36-267.00), but not for walking (OR=5.25; 95% CI,.40-77.57). Patients in the paresis subgroup experienced more favorable motor and functional recovery than did those in the paralysis subgroup. CONCLUSIONS: Tibialis anterior muscle MEPs registered in subacute phase after stroke may provide important prognostic information, both for motor recovery of the crural muscles and for the ability to perform independent transfers in patients with initial complete paralysis of the lower extremity. Vastus medialis muscle MEPs were not predictive for motor and functional recovery.
Radionuclide venography has been performed in 180 patients for evaluation of the lower extremity deep venous system. 21 of these patients suffered from a pelvic vein thrombosis, in 5 out of these patients a systemic-portal shunting of blood has been discovered. Also the collateral circulation in the patients with a lower extremity deep venous thrombosis has been clearly shown. Radionuclide venography is a relatively simple method of thrombus detection in the pelvic veins and the lower extremity deep venous system.
OBJECTIVE: The aim of our study was to evaluate the efficacy of MDCT angiography in the assessment of lower limb peripheral arterial occlusive disease. MATERIALS AND METHODS: Twenty-four patients (representing 27 cases) with symptomatic lower extremity peripheral arterial occlusive disease underwent both MDCT angiography and digital subtraction angiography of the aortoiliac and lower extremity arteries. For data analysis, the arterial system was divided into 10 segments. Each segment was classified as normal, mildly stenotic, moderately stenotic, severely stenotic, or occluded. In evaluating MDCT angiographic findings, cross-sectional images were mainly observed by scrolling. The diagnostic accuracy of MDCT angiography was determined, using digital subtraction angiography as the standard reference. The extent of calcification in each segment was also assessed on MDCT angiography and was classified as absent, mildly calcified, or severely calcified. RESULTS: Of the 480 segments studied, 470 were assessable on both digital subtraction angiography and MDCT angiography. On digital subtraction angiography, 142 stenoocclusive segments (20 mildly stenotic, 14 moderately stenotic, 25 severely stenotic, and 83 occluded) were detected. With regard to the detection of segments that had more than mild stenosis, the sensitivity, specificity, and accuracy of MDCT angiography were 99.2%, 99.1%, and 99.1%, respectively. In the 421 noncalcified and mildly calcified segments, the sensitivity, specificity, and accuracy of MDCT angiography for the detection of more-than-mild stenosis were 100%, 100%, and 100%, respectively. CONCLUSION: MDCT angiography is a reliable method for evaluating the aortoiliac and lower extremity arteries.
BACKGROUND: Sarcopenia, an age-related reduction in muscular mass and strength, may cause a decline in physical functioning and subsequent loss of autonomy. It has been suggested that strength is associated with lower extremity function mainly in the lower portion of the range of strength. Identifying the threshold under which strength is most critical to function may help in targeting groups who may benefit most from exercise interventions. METHODS: The study uses data from the Women's Health and Aging Study. The study population, recruited by screening a population-based sample aged 65 years and older, comprised 1,002 women who represent the one-third most disabled women without severe cognitive impairment living in the community. Knee extensor and hip flexor strength were assessed using a hand-held dynamometer. Lower extremity performance was evaluated using tests of walking, standing balance, and rising from a chair. RESULTS: Among women tested for strength (n = 892), those who could walk (97%), do the side-by-side stand (87%), or complete 5 chair stands (74%) had significantly greater strength. Walking speed was linearly associated with knee extensor strength over the entire range of strength, but its association with hip strength was limited to values below 15 kg. Time for five chair stands was associated with knee extensor and hip flexor strength below 10 and 15 kg, respectively, and no significant association was detected above these values. Stronger women were more likely to hold balance for 10 sec in the side-by-side, semi-tandem, and tandem positions. The percentage of the variance in performance explained by strength alone was always lower than 20%. CONCLUSIONS: In this population, which does not include the strongest older women, there is a departure from linearity in the relationship between muscular strength and some measures of lower extremity performance.
For spinal anesthesia of only one lower extremity, effect factors, assumed to influence the level of anesthesia including the degree of head-down position of the patients during injection, the volume of the drug and the rate of its injection, are studied using 0.2% hypobaric tetracaine solution in water. Seventy-two patients having the surgery of one lower extremity were divided into 7 groups according to the difference in the degree of head-down position (0, 2 and 5 degrees), in the volume (3, 5 and 7 ml) and the rate (0.2, 0.1 and 0.05 ml.s-1) of injection of tetracaine solution. Patients, in lateral position with the operative side up during injection and 20 minutes after injection, were checked for the level of hypesthesia and analgesia on both operative side and non-operative side. Except 2 groups of the patients who were in horizontal position during injection or who are injected with 7 ml of tetracaine solution all at once, the upper level of analgesia in the operative side is well controlled at T10, although in some patients the additional injection of small amount of tetracaine solution was needed. In these patients, the analgesic level in the non-operative side is restricted within S level, and HR and BP changes were very slight. The rate of injection had no effect on the analgesic level on both operative side and non-operative side.
In diabetic patients with ischaemia of the lower extremities and mediocalcinosis the diagnosis of ischaemia is still difficult. One of the methods which give an objective idea of the microcirculation is transcutaneous oximetry. In the submitted paper the authors explain the principle and problems of assessment with recommendations for the practical application of the method, in particular in indication for angiography of the lower extremities in the presence of the diabetic foot syndrome with regard to probable spontaneous healing of defects and application of the method for following up the effect of revascularization operations.