Unusually high mitochondrial alpha glycerophosphate dehydrogenase activity in rat brown adipose tissue.

Brown adipose tissue of the rat has been found to have an unusually high activity of mitohondrial alpha-glycerophosphate dehydrogenase (alpha-GPD) when assayed both by a histochemical staining procedure and by a quantitative biochemical method with isolated mitochondria. In contrast to succinic, glutamic, and beta-hydroxybutyrate dehydrogenases, all mitochondrial enzymes, the activity of alpha-GPD in brown fat was 10 times that in liver, more than 20 times that in white adipose tissue, and 9 times that in kidney. The soluble NAD-linked alpha-GPD was also higher in brown adipose tissue than in white adipose tissue, liver, or kidney, but the differences were much less marked. The possible importance of the high activity of mitochondrial alpha-GPD in the regulation of synthesis of esterified lipid and in thermogenesis in brown fat is discussed.

Glutathione-dependent peroxidative metabolism in the alveolar macrophage.

Phagocytosis by rabbit alveolar macrophages (AM) is accompanied by increases in O(2) consumption, glucose oxidation, and H(2)O(2) formation. Two aspects of the interrelations between these metabolic features of phagocytosis have been studied.First, the following evidence indicates that glutathione, glutathione reductase, and peroxidase serve as a cytoplasmic shuttle between H(2)O(2) and NADPH-dependent glucose oxidation: (a) AM contain 5.9 mmumoles of reduced glutathione per 10(6) cells and exhibit glutathione peroxidase and NADPH-specific glutathione reductase activity; (b) oxidized glutathione potentiates NADP stimulation of glucose oxidation; (c) an artificial H(2)O(2)-generating system stimulates glucose oxidation; (d) the cell penetrating thiol inhibitor, N-ethylmaleimide diminishes glucose oxidation. This effect largely depends on inhibition of the glutathione system rather than on inhibition of either H(2)O(2) formation or enzymes directly subserving glucose oxidation.Second, three potential H(2)O(2)-generating oxidases have been sought. No cyanide-insensitive NADH or NADPH oxidase activity could be detected. D-amino acid oxidase activity was 0.48 +/-0.07 U/10(6) cells with D-alanine as substrate.

Peripheral arterial disease in randomized trial of estrogen with progestin in women with coronary heart disease: the Heart and Estrogen/Progestin Replacement Study.

BACKGROUND: Postmenopausal estrogen use has been associated with reduced carotid atherosclerosis in observational studies, but this relationship has not been confirmed in a clinical trial. The impact of estrogen on atherosclerotic disease in other peripheral arteries is unknown. METHODS AND RESULTS: Postmenopausal women with coronary heart disease (CHD) and an intact uterus (n=2763) were randomly assigned to conjugated equine estrogens (0.625 mg) combined with medroxyprogesterone acetate (2.5 mg) daily or to placebo in a secondary CHD prevention trial. This analysis focuses on incident peripheral arterial procedures and deaths in the 2 treatment groups; peripheral vascular disease was a predefined secondary outcome. During a mean of 4.1 years of follow-up, 311 peripheral arterial events were reported in 213 women, an annual incidence of 2.9%. The number of women who had peripheral arterial events was 99 among those assigned to active estrogen/progestin and 114 among those assigned to placebo, a nonsignificant difference (relative hazard 0. 87, 95% CI 0.66 to 1.14). In the placebo group, hypertension and diabetes mellitus were independently associated with higher rates of peripheral arterial events, and plasma HDL cholesterol and body mass index were associated with lower rates of peripheral arterial events. In the estrogen/progestin group, current smoking and diabetes were independent predictors of peripheral arterial events. Incident peripheral arterial disease was not a significant predictor of coronary, cardiovascular, or total mortality. CONCLUSIONS: Treatment with oral conjugated estrogen plus medroxyprogesterone acetate was not associated with a significant reduction in incident peripheral arterial events in postmenopausal women with preexisting CHD.

Smoking and mortality among older women: the study of osteoporotic fractures.

BACKGROUND: Relatively few studies have been focused on the effect of smoking among older individuals. The goal of this study is to investigate the relationship between smoking status and cause-and age-specific mortality among elderly women. METHODS: Women aged 65 years and older and living in four geographical areas (Baltimore, Md, Minneapolis, Minn, Pittsburgh, Pa, and Portland, Ore) were recruited from various population-based listings for participation in the multicenter Study of Osteoporotic Fractures between September 1986 and October 1988 (N=9704). During a mean follow-up of 4.9 years (<99% complete), 751 deaths occurred. The date and cause of death were ascertained, and the relationship between mortality and current and past smoking status was analyzed using Cox proportional hazards modeling techniques. RESULTS: Compared with nonsmokers, women smokers aged 65 to 74 years have a more than twofold increase in mortality attributable to increases in both cardiovascular and cancer mortality; death from smoking-related cancers increased eight- to 10-fold. Women 75 years and older who smoke have a small overall increased relative risk (RR) of mortality (RR=1.4; 95% confidence interval [CI], 0.9 to 2.3), but more than five-fold increased risk of dying from a smoking-related cancer (RR=5.2; 95% CI, 1.6 to 16.8). All-cause and cardiovascular death rates approach those of nonsmokers within 10 years after a woman quits smoking; morality from smoking-related cancers remains elevated for at least 23 years. CONCLUSIONS: The harmful effects of continuing to smoke are apparent even among women aged 75 years and older.

Bone mineral density and blood flow to the lower extremities: the study of osteoporotic fractures.

This study tests the hypothesis that reduced blood flow to the lower extremities may affect bone remodeling, resulting in a decrease in bone mineral density (BMD). BMD was measured in the axial and appendicular skeleton of 1292 elderly women (mean age, 71 years) enrolled in the Study of Osteoporotic Fractures. The ratio of the posterior tibial and brachial systolic blood pressures, the ankle/arm index, was used as a measure of blood flow to the legs. In the cross-sectional analysis, this index was positively correlated with BMD at the radius, calcaneus, and hip, but not at the spine. A decrease in the index of 2 standard deviations (SD) (as might occur in patients with moderate arterial disease) was associated with a decrease of 3.7% (95% CI, 1.7%, 5.8%) in hip BMD. The effect size at the hip decreased from 3.7 to 1.8% (and was not statistically significant) when adjustment was made for smoking and/or body mass index (BMI). In the prospective analysis, the rate of bone loss at the hip and calcaneus was greater (p < 0.05) among women whose annual decrease in ankle/arm index was more than 1 SD greater than the mean decrease. This increase was independent of estrogen use, smoking, BMI, pattern of fat distribution, history of diabetes, exercise, and ability to walk. The results from this prospective community-based study provide the first evidence that among relatively healthy older women decreased vascular flow in the lower extremities may be associated with an increased rate of bone loss at the hip and calcaneus.

The relationship between ankle brachial index, other atherosclerotic disease, diabetes, smoking and mortality in older men and women.

The goal of this study is to investigate the relationship between peripheral arterial disease and mortality in a large patient population and assess the effects of other atherosclerotic diseases, diabetes and smoking on this relationship. All patients, 50 years or older and with no history of lower extremity surgery, evaluated for lower extremity arterial disease in a university hospital peripheral vascular laboratory over a 13-year period (1977-1989) were included in the study (n = 1930). Arterial disease was assessed by measurement of the resting ankle brachial index (ABI) in these patients. The ABI was calculated by dividing the systolic pressure in the tibial arteries by the pressure in the brachial artery. Analyses of the data by use of multivariate statistical techniques and by stratification of the patient population by co-morbid condition indicate that ABI is a robust and independent predictor of all-cause mortality in both men (relative risk (RR) = 1.6, 95% confidence interval (CI) 1.3, 2.0) and women (RR = 1.9, 95% CI 1.4, 2.4). The relative risks are essentially unchanged after exclusion of all patients with clinical history of cardiovascular disease or diabetes. Similarly, a low ABI is an important risk factor for mortality among patients with a history of stroke, angina or diabetes; men and women with a history of smoking and women who are non-smokers. Therefore, the measurement of ABI, a simple, objective, non-invasive technique which can be used in the physician's office, may be useful for early identification of patients at high risk for morbidity and mortality.

Lower extremity arterial disease and the aging process: a review.

Atherosclerotic disease is a major health problem in the elderly population in the U.S. To date, most research has focused on the coronary and cerebral manifestations of the disease. Lower extremity arterial disease (LEAD) has received less attention. However, the use of simple objective non-invasive diagnostic techniques in recent population-based studies has allowed identification of asymptomatic LEAD and shown that the prevalence of disease is several fold higher than previously estimated. The prevalence increases sharply with age, from 3% in those under 60 years to over 20% at 75+ years. Detection of LEAD in the elderly provides a rapid, easy assessment of the level of atherosclerosis in the body and identifies those at high risk for mortality and morbidity. LEAD is associated with a relative risk of 4 to 5 for all cause mortality. In about 25% of those with LEAD, the disease progresses over time, leading to loss of mobility, gangrene or amputation. This review summarizes current knowledge regarding the etiology and natural history of LEAD from an epidemiologic viewpoint, delineating areas in which additional research is needed.

Segmental arterial disease in the lower extremities: correlates of disease and relationship to mortality.

The purpose of this study was to identify the correlates of disease and mortality risk associated with the presence of stenosis in the major arterial segments of the lower limb in men and women evaluated in a peripheral vascular laboratory. A total of 326 men and 249 women had unisegmental stenosis; 312 men and 275 women had multisegmental disease; 132 men and 111 women had no apparent disease. Multivariate analysis indicated that current smoking and elevated systolic blood pressure were the key risk factors associated with isolated aortoiliac and femoropopliteal arterial disease in both men and women. A history of diabetes was significantly associated with tibioperoneal disease in men while elevated systolic blood pressure was the major correlate of distal disease in women in this patient population. The relative risk of mortality was elevated 2- to 7-fold in men and women with multi- and unisegmental disease involving the aortoiliac and femoropopliteal segments; presence of tibioperoneal disease did not significantly increase mortality relative to those who were free of disease. These results suggest that the etiology and mortality risk associated with atherosclerosis in the lower extremity may vary with the anatomic site and/or severity of the lesion.

Bone mineral density and aortic calcification: the Study of Osteoporotic Fractures.

OBJECTIVE: To investigate the relationship between bone mineral density (in the axial and appendicular skeleton) and calcification of the aorta. DESIGN: Cross-sectional study. SETTING: Community-based study. PARTICIPANTS: A total of 2051 women aged 65 years and older enrolled in the Study of Osteoporotic Fractures. MEASUREMENTS: Bone mineral density (BMD) at the hip, spine, calcaneus, proximal and distal radius; calcification of the aorta (AC); demographic and lifestyle variables; dietary history; functional status; blood pressure; anthropomorphic measures. RESULTS: The prevalence of AC increased with age, ranging from 60% at ages 65 to 69 years to 96% at 85 years and older. BMD in women with calcified arterial plaques was lower (P < .001) when compared with those with no plaques, at all sites measured except the lumbar spine. After adjustment for age, BMD at the hip, spine and calcaneus was not associated with the presence of plaques; only a weak association between BMD and AC remained at the distal and proximal radius. The independent correlates of AC were age, smoking status, systolic blood pressure, coffee drinking, central obesity and a history of diabetes or stroke; current estrogen use was protective. CONCLUSIONS: The results of this study indicate that osteopenia and the deposition of calcific plaques in the wall of the aorta are independent processes that occur as women age. They are probably not causally linked.

Functional status and mobility among elderly women with lower extremity arterial disease: the Study of Osteoporotic Fractures.

OBJECTIVE: To investigate the relationship between lower extremity arterial disease, functional status, and mobility among elderly women. DESIGN: Cross-sectional study. SETTING: Community. PARTICIPANTS: 1492 healthy white women, 65 years of age or older, residing in a rural community, able to walk without the assistance of another person, and enrolled in the Pittsburgh clinic of the multicenter Study of Osteoporotic Fractures. Those with bilateral hip replacement were excluded. MEASUREMENTS: Ankle/arm index (AAI); instrumental activities of daily living (IADLs); measures of recent physical activity, muscle strength, gait and balance; general demographic, lifestyle, and physical variables. RESULTS: Women with lower extremity arterial disease (defined as an AAI of 0.9 or less) were more likely to report difficulty with one or more IADLs than were women free of this disease. After adjusting for age and other potential confounders, only difficulty with walking 2-3 blocks remained highly correlated with disease (relative risk (RR) 2.8, 95% confidence interval (CI) 1.6, 4.8). Several measures of physical activity were inversely and independently related to a low AAI. Muscle strength in the hip, arm, knee, and hand and measures of static and dynamic balance were correlated with low AAI in the univariate analysis, but most of these trends were not statistically significant after adjustment for age and other confounders. Exclusion of women with symptomatic arterial disease did not substantially affect the results obtained. CONCLUSION: Women with mild, predominantly subclinical, lower extremity arterial disease living in the community have decreased functional status and mobility.

The relationship between ankle-arm index and mortality in older men and women.

OBJECTIVE: To determine whether the ankle-arm blood pressure index is a useful predictor of mortality in a large group of patients aged 50 or older. DESIGN: Cohort study over a 13-year period. SETTING: Peripheral vascular laboratory in a hospital affiliated with an academic health center. PARTICIPANTS: 1,027 male and 903 female patients referred for arterial evaluation. OUTCOME MEASURES: All-cause and cause-specific mortality. RESULTS: A decrease in ankle-arm index was a strong independent predictor of all-cause mortality [relative risk (RR) for men = 1.8(95% CI 1.5, 1.9); for women = 1.5, (1.2, 2.0)] and atherosclerotic heart disease mortality [RR for men = 2.0 (1.4, 2.9); for women = 2.1 (1.4, 3.1)]. The risk of mortality was inversely proportional to the ankle-arm index. No relationship was found between the index and mortality due to stroke or cancer. CONCLUSIONS: These results suggest that a decreased ankle-arm index has important prognostic significance for mortality due to atherosclerotic heart disease in older men and women. Measurement of this index may be useful in identifying those at high risk who may benefit from aggressive therapeutic intervention.

Back problems and atherosclerosis. The Study of Osteoporotic Fractures.

STUDY DESIGN: A cross-sectional and prospective study of osteoporotic fractures. OBJECTIVES: To investigate the correlation between lower extremity arterial disease or history of cardiovascular disease and back pain, back function, osteoporosis, and vertebral fractures. BACKGROUND: It has been postulated that atherosclerosis may compromise blood flow to bone and soft tissues in the back, causing pain and disability. Recent studies have presented conflicting results. METHODS: At baseline, information on back pain and function, general functional status, cardiovascular history, and general lifestyle variables was obtained from 1492 elderly white women (mean age, 71 years) enrolled in the Study of Osteoporotic Fractures. Lateral radiographs of the lumbar and thoracic spine were obtained, and lower extremity arterial disease was assessed. Follow-up information was obtained an average of 3.7 years later. RESULTS: At baseline, 82 women had arterial disease, 443 had a history of cardiovascular disease, and 277 had vertebral fractures; 58 women had one or more additional vertebral fractures during the follow-up period. After adjustment for age, women with cardiovascular disease were more likely to have back pain and disability as a result of the back pain than women free of cardiovascular disease; at the follow-up examination, the back-related disability was more than twice as likely to have worsened in the cardiovascular disease group. No correlation was found between arterial disease and back problems. Neither the prevalence of vertebral fractures at baseline, nor the incidence of vertebral fractures was associated with the presence of arterial disease or cardiovascular disease. CONCLUSIONS: Results indicated that back problems in elderly women are associated with self-reported cardiovascular disease, but not with objectively assessed lower extremity arterial disease.

Back problems among postmenopausal women taking estrogen replacement therapy: the study of osteoporotic fractures.

STUDY DESIGN: Cross-sectional and prospective. OBJECTIVES: To investigate the association between estrogen replacement therapy use, back pain, and back function in a large cohort of elderly women. BACKGROUND: Several studies have suggested that women who use estrogen replacement therapy may be more likely to experience back pain than those who do not. However, the relationships between estrogen replacement therapy, back pain, and impaired back function have not been clearly delineated. METHODS: At baseline information on estrogen replacement therapy use, functional status, back pain and function, and general lifestyle variables was obtained from 7209 elderly white women (mean age 71 years)enrolled in the Study of Osteoporotic Fractures. Lateral radiographs of the lumbar and thoracic spine were taken at baseline and at the third clinic visit, an average of 3.7 years after the baseline visit. Bone mineral density at the hip and spine was measured approximately 2 years after baseline. Follow-up information on back pain and function was also obtained at the third clinic visit. RESULTS: A total of 1039 (14.4%) women were using estrogen replacement therapy at baseline, 2016(28.0%) reported former use, and 4154 (57.6%) had never used estrogen replacement therapy. Compared with never-users, a statistically significant higher percentage of current estrogen users reported clinical back pain (52.7% vs. 43.4%) and back impairment (12.3% vs. 9.2%) at baseline and at the follow-up visit (pain 50.8% vs. 41%; impairment 16.0% vs. 12.1%). This occurred despite a higher prevalence of vertebral fractures in never-users of estrogen at the baseline visit. Current and former estrogen users without vertebral fractures had statistically significant higher likelihoods of having back pain and back dysfunction at both the baseline and third follow-up visit. The increased likelihood of back pain and back impairment in current and former estrogen users remained despite statistical adjustment for age, vertebral fracture, body mass index,smoking history, parity, exercise, arthritis, and diabetes in multivariate models. The relative risk (95%confidence interval) for impaired back function in former and current users at follow-up was 1.1 (0.9, 1.3) and 1.6 (1.3, 2.0), respectively. CONCLUSIONS: Our results indicate that postmenopausal estrogen use is associated with an increased likelihood of back pain and impaired back function in elderly white women.

Lumbar olisthesis and lower back symptoms in elderly white women. The Study of Osteoporotic Fractures.

STUDY DESIGN: A Cross-sectional study. OBJECTIVES: To determine the prevalence of lumbar olisthesis among white women aged 65 years and older and its relation to low back pain and back function. BACKGROUND: Degenerative changes in the lumbar spine of elderly individuals may affect spinal stability, causing olisthesis (subluxation) of the lumbar spine. Neither the prevalence of this condition in the United States nor its relation to back symptoms has been studied previously. METHODS: Lateral radiographs of the lumbar spine for 788 women aged 65 years and older who were enrolled in the Study of Osteoporotic Fractures were digitized. Olisthesis (antero- and retro-) was assessed at L3-L4, L4-L5, and L5-S1. Back pain and function also were assessed. RESULTS: When olisthesis was defined as subluxation of 3 mm or more at any of the three levels studied, the overall prevalence of anterolisthesis was 29% and that of retrolisthesis was 14%. In 90% of women with anterolisthesis and 88% of women with retrolisthesis, subluxation occurred at a single vertebral level. The prevalence of anterolisthesis and retrolisthesis did not vary by smoking status, presence of diabetes, or history of oophorectomy. Anterolisthesis was not associated with the presence of back symptoms. Only retrolisthesis at L3-L4 was associated with a statistically significantly increased likelihood of lower back pain, greater severity of back pain, and impairment of back function. CONCLUSIONS: Anterolisthesis of 3 mm or more in the lower lumbar spine is relatively common among elderly women but is not correlated with back problems. Retrolisthesis at L3-L4 is associated with increased back pain and impaired back function.

Modulation of the biologic activity of the rabbit intervertebral disc by gene therapy: an in vivo study of adenovirus-mediated transfer of the human transforming growth factor beta 1 encoding gene.

STUDY DESIGN: In vivo studies using a rabbit model to determine the biologic effects of direct, adenovirus-mediated transfer of a therapeutic gene to the intervertebral disc. OBJECTIVES: 1) To deliver an exogenous therapeutic gene to rabbit lumbar intervertebral discs in vivo, 2) to quantify the resulting amount of gene expression, and 3) to determine the effect on the biologic activity of the discs. SUMMARY OF BACKGROUND DATA: Although growth factors such as transforming growth factor beta 1 appear to have promising therapeutic properties, there currently is no practical method for sustained delivery of exogenous growth factors to the disc for the management of certain chronic types of disease (e.g., disc degeneration). A possible solution is to modify the disc cells genetically through gene transfer such that the cells manufacture the desired growth factors endogenously on a continuous basis. METHODS: Saline, with or without virus, was injected directly into lumbar discs of 22 skeletally mature female New Zealand white rabbits. Group 1 (n = 11) received the adenovirus construct Ad/CMV-hTGF beta 1 containing the therapeutic human transforming growth factor beta 1-encoding gene. Group 2 (n = 6) received adenovirus containing the luciferase marker gene. Group 3 (n = 5) received saline only. The rabbits were killed 1 week after injection. Immunohistochemical staining for human transforming growth factor beta 1 was performed on the disc tissues of one rabbit from Group 1. Nucleus pulposus tissues from the remaining rabbits were cultured in serumless medium. Bioassays were performed to determine human transforming growth factor beta 1 production and proteoglycan synthesis. RESULTS: Discs injected with Ad/CMV-hTGF beta 1 exhibited extensive and intense positive immunostaining for transforming growth factor beta 1. The nucleus pulposus tissues from the discs injected with Ad/CMV-hTGF beta 1 exhibited a 30-fold increase in active transforming growth factor beta 1 production, and a 5-fold increase in total (active + latent) transforming growth factor beta 1 production over that from intact control discs (P < 0.05). Furthermore, these tissues exhibited a 100% increase in proteoglycan synthesis compared with intact control tissue, which was statistically significant (P < 0.05). CONCLUSIONS: The results of this study suggest that the intervertebral disc is an appropriate site for adenovirus-mediated transfer of exogenous genes and subsequent production of therapeutic growth factors. Gene therapy therefore may have useful applications for study of the basic science of the intervertebral disc and for clinical management of degenerative disc disease.

Degenerative lumbar listhesis and bone mineral density in elderly women. The study of osteoporotic fractures.

STUDY DESIGN: A cross-sectional and prospective study. OBJECTIVES: To investigate the association between lumbar listhesis in elderly white women and bone mineral density at the spine, hip, radius, and calcaneus. SUMMARY OF BACKGROUND DATA: Several types of degenerative spinal changes have been found to be associated with high bone mineral density at the spine and other body sites. METHODS: Lateral radiographs of the lumbar spine for 1400 elderly women enrolled in the Study of Osteoporotic Fractures were digitized. Listhesis (antero and retro) was assessed at L3-L4, L4-L5, and L5-S1. Bone mineral density was measured at the spine, hip, calcaneus, and the distal and proximal radius. RESULTS: After adjusting the data for age and body mass index, retrolisthesis at L3-L4, L4-L5, and L5-S1 was associated with mean spinal bone mineral density levels that were 9% to 13% higher compared with those levels in women with no listhesis (P < 0.0001). In addition, bone mineral density at the hip and appendicular sites increased from 4% to 9%. The mean lumbar spinal bone mineral density of women with anterolisthesis at L3-L4 was 12% higher (P < 0.05) than that of women with no listhesis; it was the same for both groups at L4-L5 and was 7% lower (P < 0.005) at L5-S1. At L5-S1 the bone mineral density level at the hip and appendicular sites was also lower among the women with anterolisthesis at that level. CONCLUSIONS: This study suggests that retrolisthesis, like other spinal degenerative diseases, is associated with increased spinal bone mineral density. Anterolisthesis, however, may involve a different etiology, because its association with bone mineral density varies by spinal level.

A hypothesis of synergism: the interrelationship of T3 and insulin to disturbances in metabolic homeostasis.

While the role of abnormal insulin homeostasis in the pathogenesis of Type-2 diabetes mellitus is well established, the importance of the canonical role of T(3) on Type-2 diabetes or the homeostasis of glucose, lipid, and energy balance has not been addressed. Based on the available evidence from molecular biology, the pivotal regulatory role of T(3) in major metabolic pathways and glycemic control can be delineated by mapping the specific action sites of T(3) and insulin on the metabolic pathways of the glucose-lipid cycle. The current paper presents an integrative hypothesis of the synergistic relationship of T(3) and insulin in metabolic homeostasis and abnormalities.

Assessment of the disturbances in metabolic homeostasis: a hypothesis of synergism.

Based on the hypothesis that a synergistic interaction between triiodothyronine (T(3)) and insulin contributes to abnormalities in glucose and other metabolic pathways, the mechanisms underlying the impairment of metabolic homeostasis (MH) and the development of type-2 diabetes (DM) were investigated via a proposed homeostatic model, [(FG*TG)/T3*FI)]. The MH model characterizes the relationship between T(3) and insulin and the levels of triglycerides (TG), fasting insulin (FI), and fasting glucose (FG) and is introduced as a clinical method to assess insulin sensitivity and the status of metabolic homeostasis in lieu of current screening models advocated by the by American Diabetic Association (ADA). The present study validated the hypothetical model in a sample of 110 African-American women.

Carpal tunnel release under intravenous regional or local infiltration anaesthesia.

Fifteen patients with bilateral carpal tunnel syndrome underwent surgery using intravenous regional anaesthesia (IVRA) on one hand and local infiltration anaesthesia (LA) on the other. All 30 carpal tunnel releases were performed without complication. Patient tolerance for IVRA and LA was similar. Six patients preferred the LA, eight preferred IVRA and one had no preference. Tourniquet time averaged 16 minutes when LA was used and 24 minutes with IVRA (P<0.05). Use of local anaesthesia allows more expeditious surgery and limits costs, but intravenous regional anaesthesia is recommended if epineurotomy, internal neurolysis or flexor tenosynovectomy are planned.

Wound-healing risk factors after open reduction and internal fixation of calcaneal fractures.

This retrospective study investigated outcomes of wound healing in a series of 63 consecutive patients with 64 fractures of the calcaneus who underwent open reduction and internal fixation done by two surgeons experienced in this fracture during a 3-year period. Thirty-nine patients were managed preoperatively as outpatient referrals before surgery. Twenty-four patients were admitted directly to the trauma service and were managed as inpatients preoperatively. Minimum patient follow-up was 6 months, with an average follow-up of 18 months. A trend correlating the time between injury and operative intervention with the incidence of complications in wounds was noted; the incidence rose in patients who underwent surgery >5 days after their injury. Two-layered closures had a lower incidence of dehiscence compared to single-layered tension-relieving sutures. Patients with a higher body-mass index (BMI) (kg/ m2) took longer to heal their wounds. Strong trends were noted to link BMI and severity of fractures. In the outpatient group, a history of active smoking preoperatively correlated with increased time to wound healing. In 43 patients, there were no wound-healing complications. In 21 feet, there were varying degrees of wound dehiscence. Average wound healing took 47 days. Risk factors for complications in the wound after calcaneal open reduction and internal fixation include single layered closure, high BMI, extended time between injury and surgery, and smoking. Age, type of immobilization, medical illness (including diabetes), type of bone graft, or use of a Hemovac did not influence wound healing.