Hydroxyapatite-coated total hip femoral components in patients less than fifty years old. Clinical and radiographic results after five to eight years of follow-up

One hundred and thirty-three patients (152 hips) who were an average of thirty-nine years old (range, sixteen to forty-nine years old) received a proximally hydroxyapatite-coated femoral prosthesis as part of a total hip arthroplasty and were followed for a minimum of five years (average, 6.4 years; range, five to 8.3 years) or until revision. The average Harris hip score was 47 points (range, 22 to 77 points) preoperatively and 93 points (range, 49 to 100 points) at the time of the latest clinical evaluation. Two patients who had a well fixed femoral implant had activity-limiting pain in the thigh at the time of the most recent examination. Radiographic changes consistent with bone-remodeling (cortical hypertrophy and bone condensation) typically were seen around the mid-part of the shaft of the prosthesis. Forty-eight (32 per cent) of the 148 hips that were included in the radiographic analysis demonstrated a small amount of erosive scalloping in either zone 1 or zone 7 of Gruen et al., and intramedullary osteolysis was suspected in only one hip. All stems were radiographically osseointegrated according to a modification of the criteria described by Engh et al. Four stems were revised, but none of the revisions were performed because of mechanical failure (two stems were revised in conjunction with a revision of the cup because of pain; one, because of an infection; and one, after a traumatic femoral fracture that occurred six years postoperatively). Thus, the rates of aseptic and mechanical failure were both 0 per cent. The combined rate of failure, which included the two stems that were revised because of pain and the two stems that were associated with pain that limited activity, was 2.6 per cent (four of 152 stems). The over-all clinical results associated with hydroxyapatite-coated femoral components were excellent in this group of young patients after intermediate-term follow-up. A review of serial radiographs showed mechanically stable implants with osseous ingrowth, evidence of stress transmission at the middle part of the stem, and minimum endosteal osteolysis.     

Total hip arthroplasty performed without cement in patients with femoral head osteonecrosis who are less than 50 years old

Seventy-two cementless total hip arthroplasties were performed by a single surgeon in 58 patients with the diagnosis of femoral head osteonecrosis. All patients were less than 50 years old (mean, 37 years). The mean follow-up was 84 months with a minimum of 48 months. Good-to-excellent results were maintained at final follow-up in 94% of the hips. Revision rate was 1.5% each for the cups and the stems. Mechanical failure rate was 7.6% for the cups, and 6% for the stems. If the results were analyzed excluding the data from the group of patients who received the Mittelmeier prostheses, the mechanical failure rates for the cups was 0% and for the stems was 4.2%. The probability of survival for the entire series using revision as the endpoint was 96.9% at 11 years. Survival probability decreased to 88.5% if radiographic failures were included. Excluding the Mittelmeier prostheses, survival probability was estimated to be 100% for the cups using both revision and radiographic failures as endpoints; for the stems, the survival probability was 98.0% using revision as the endpoint and 95.8% including radiographic failures. Femoral osteolysis was observed in 1.5% of the hips. No hip had acetabular osteolysis. No measurements of polyethylene wear were attempted in this study. These results appeared superior to total hip arthroplasties done with early cementing techniques in this population of young patients with femoral head osteonecrosis.     

The Stanmore total hip arthroplasty. A 15- to 20-year follow-up study

An ongoing study was made of 804 primary Stanmore total hip prostheses implanted in 839 patients between 1973 and 1991. The earliest surviving implants were brought back for radiologic and clinical review in 1995 at an average of 17 years after surgery. The remainder of the patients still living were sent a questionnaire to assess their current status. Survivorship was 95% at 10 years, 85% at 15 years, and 73% at 20 years. The average Merle d'Aubigné-Postel score was excellent up until 14 years. Patient satisfaction remained high until 22 years. Overall, 10% of the prostheses had failed. The results of this study suggest that the Stanmore prosthesis is capable of producing satisfactory long-term results that compare favorably with those of other cemented prostheses.     

Failed cementless total hip arthroplasty for osteoarthrosis due to hip dysplasia. A minimum five-year follow-up study

PROBLEM: Apoptosis has been accepted as a mechanism for maintaining tolerance in the immune system. The induction of apoptotic cell death can also be a possible outcome of the lymphocyte activation. Expression of Fas ligand (FasL) by the human trophoblast has been proposed as a mechanism providing protection against the lytic action of decidual immune cells. The aim of this study was to determine whether decidual T cells undergo apoptosis during abortion. METHOD OF STUDY: We studied apoptosis of T cells isolated from the first-trimester decidua in 12 women after spontaneous or elective abortion. We used gel electrophoresis to detect DNA fragmentation. Cells undergoing DNA fragmentation also were identified by DNA analysis using flow cytometry. This method was based on the accumulation of ethanol-fixed apoptotic cells in the sub-G0/G1 peak of the DNA content as a result of the loss of DNA fragments from the cells and because of a reduced DNA ability to be stained by propidium iodide. In addition, the expression of Fas antigen on the surface of decidual T cells (CD3+) also was determined. RESULTS: We did not detect apoptosis by the "ladder" technique. However, the apoptotic index (the percentage of positive cells per total number of cells) ranged from 2% to 24% using flow cytometry. CONCLUSIONS: Trophoblast cells usually fail to stimulate alloantigen-specific T cells, but they may express nonclassical major histocompatibility complex alloantigens to which mothers can produce immunoglobulin G alloantibody, which requires T helper cell activation. The apoptosis of T cells in the human decidua, probably through Fas-FasL signaling, may be a defense mechanism against rejection of the fetal allograft by the maternal immune system.     

Renal transplantation in children less than two years old

Twenty-one infants, 2 years old or younger, received 21 renal transplants between 1983 and 1995. Six of the transplantations were performed from 1983 to 1989, and the remaining 15 were performed from 1990 to 1995. The median age at transplantation was 16.0 months and the median body weight was 9.0 kg. Living-related donor kidneys were used in 15 cases, an adult cadaveric donor kidney was used in one case, and pediatric cadaveric donor kidneys were used in five cases. All grafts were placed intra-abdominally. The immunosuppressive therapy consisted of cyclosporine, azathioprine, and prednisolone. No prophylactic antithymocyte globulins were used. Five infants have died, one with a functioning graft and four after loss of graft function. All graft losses and deaths occurred during the first 6 months after transplantation. The 5-year patient survival and graft survival rates were 87% for recipients of living donor grafts and 44% for recipients of cadaveric grafts. The median height SD score increased from -3.7 before operation to -1.9 at 1 year, -0.7 at 3 years, and -1.1 at 5 years. The glomerular filtration rate in absolute values remained stable in all infants, whereas a reduction in glomerular filtration rate related to body surface area was seen at follow-up, 5 years after transplantation. We conclude that renal transplantation can be performed with good long-term results in children less than 2 years old.     

5- to 18-year follow-up study of cemented total knee arthroplasty for patients 55 years old or younger

BACKGROUND: Although both expectant mothers and expectant fathers complain of fatigue during the last trimester of pregnancy, studies have focused exclusively on mothers. This pilot study examined parents' levels of morning or evening fatigue, number of uninterrupted sleep periods and length of sleep during the last trimester of pregnancy; and the relationship of sleep to parents' reports of fatigue. METHODS: Data were collected from 24 midwestern, nulliparous couples, who completed the Visual Analog Scale for Fatigue each morning and each evening on 4 consecutive days during the last trimester. Concurrently, the couples recorded sleep and wake periods in an activity diary. RESULTS: Expectant mothers but not expectant fathers reported increasing levels of fatigue, especially morning fatigue, as the pregnancy progressed. Expectant fathers and mothers did not differ either in the night-time mean number of minutes of sleep obtained, or in the mean number of night-time uninterrupted 90-minute sleep cycles obtained. Fatigue and sleep were not significantly related for either mothers or fathers. CONCLUSIONS: These findings support the multidimensional nature of fatigue and indicate a need for perinatal health caregivers to develop individualized interventions for mothers during the last trimester of pregnancy. Fathers should also participate in future research of factors influencing the prenatal and postpartum experience.     

The John Charnley Award. Prophylaxis of fat and bone marrow embolism in cemented total hip arthroplasty

The efficiency of a new cementing technique developed to prevent the risk of intraoperative pulmonary embolism was assessed. Seventy patients with coxarthrosis entered into a prospective, randomized clinical trial. In the control group of 35 cases the total hip replacement was cemented conventionally. In the second group a proximal drainage placed along the Linea aspera, and a distal drainage placed in the diaphysis, created a vacuum in the medullary cavity of the femur during the insertion of the stem. The operation was performed with the patient under blood gas analysis and hemodynamic and transesophageal echocardiography monitoring. Severe transatrial embolic events were observed during the insertion of the femoral component in 94% of the cases of the control group and in 14% of the cases of the vacuum group; the difference is statistically significant. A significant decrease of arterial partial pressure of O2 (-40.8 mm Hg) and increase of the pulmonary shunt values (+28.3%) occurred 5 minutes after the observation of embolic events in the cases operated on conventionally, but these parameters showed minimal changes in the vacuum group. The rise of intramedullary pressure in the femur is the most decisive pathogenic factor of pulmonary embolism during total hip arthroplasty. The logical prophylactic measure to prevent intravasation of fat and bone marrow is to create sufficient drainage. The cohorted investigation showed the value of the vacuum cementing technique for a substantial reduction of intraoperative embolism and pulmonary impairment.     

Failure of the Mecring screw-ring acetabular component in total hip arthroplasty. A three to seven-year follow-up study

We prospectively studied the results of 411 consecutive total hip arthroplasties with a Mecring screw-ring acetabular component inserted without cement combined with a Stanmore femoral stem inserted with cement. The duration of follow-up ranged from three to seven years (mean, four years and six months). Three hundred and thirty-one patients (378 hips) were available for physical examination and had a complete set of radiographs. The clinical result was good or excellent for 82 per cent (309) of the 378 hips. However, the rate of radiographic loosening of the acetabular component, as evidenced by migration at the most recent follow-up examination, was alarmingly high: 25 per cent (ninety-five) of the 378 hips. In general, these patients did not have serious clinical symptoms. The cups in women migrated significantly more often (p = 0.003) than those in men. Migration was also more frequent in patients who were less than fifty-one years old and in patients in whom the index procedure was a revision arthroplasty, but these differences were not significant. Twenty-one (6 per cent) of the acetabular cups were revised for aseptic loosening. The high rate of radiographic loosening has led us to abandon the use of the Mecring screw-ring acetabular component.     

The John Charnley Award. Inhibition of wear debris mediated osteolysis in a canine total hip arthroplasty model

In this study the efficacy of an oral bisphosphonate therapy to inhibit wear debris mediated bone resorption was evaluated in a canine total hip replacement model. Adult canines were randomized to three groups (n = 8 each) with a right uncemented total hip replacement performed on each animal. Group I (control) received no particulate debris. In Groups II and III, a mixture of 1 x 10(9) particles were introduced into the proximal femoral gap intraoperatively. The particle mixture consisted of fabricated ultra high molecular weight polyethylene (mean 2.3 microns, 90% by number), titanium alloy (mean 3.1 microns, 5%), and cobalt chrome alloy (mean 0.8 micron, 5%). Group III canines additionally received oral drug therapy (5 mg once a day, alendronate sodium) which was begun on postoperative Day 7 and continued until the time of sacrifice. Postoperatively, all animals were allowed 24 weeks of full ambulation before euthanasia. Radiographs obtained preoperatively, postoperatively, and at time of sacrifice were evaluated for periprosthetic osteolysis. Interfacial tissues were examined histologically and placed in organ culture and the supernatants were assayed for prostaglandin E2 and interleukin-1. One animal receiving debris (Group II) suffered a periprosthetic fracture and was sacrificed from the study. Radiographically, one of eight Group I (control) and six of seven canines from Group II (debris) had periprosthetic radiolucencies with endosteal scalloping develop. In contrast, only one of eight animals from Group III (debris + alendronate) had periprosthetic radiolucencies develop. Whereas tissues from control animals were mostly fibrous and acellular, tissues from both experimental groups had significant macrophage infiltration. Levels of prostaglandin E2 and interleukin-1 were elevated significantly in periprosthetic tissues from both experimental groups compared with controls. Continuous administration of alendronate effectively inhibited bone lysis for the 24-week duration of the study. This is consistent with the literature indicating that alendronate is incorporated in the mineralizing matrix making it refractory to osteoclastic resorption. This report has significant clinical implications for controlling the most common cause of implant failure.     

Resection hip arthroplasty for malignant pelvic tumor. Outcome in 5 patients followed more than 2 years

BACKGROUND: Vasoactive intestinal peptide (VIP) has been reported to have some properties that provide protection from lung injury. Furthermore, its protective effect in cold storage of donor lungs has been confirmed. We examined its effect and the timing of administration in an in vivo rat lung transplantation model. METHODS: All lungs were flushed with low-potassium dextran-1% glucose solution, and orthotopic left lung transplantations were performed. Rats were divided into four groups (n = 6). Group I received no preservation or storage. Groups II, III, and IV grafts were stored for 18 hours at 4 degrees C. Group II received no VIP. Group III received VIP (0.1 g/ml) via the flush solution. Group IV recipients received VIP (3 microg/kg) intravenously just after reperfusion. Twenty-four hours after transplantation, the right main pulmonary artery and right main bronchus were ligated, and the rats were ventilated with 100% O2 for 5 minutes. Mean pulmonary arterial pressure, peak airway pressure, blood gas analysis, serum lipid peroxide level, tissue myeloperoxidase activity, and wet-dry weight ratio were measured. RESULTS: The partial O2 tension values of groups III and IV were better than group II (groups II, III, and IV: 147.4 +/- 71.4, 402.1 +/- 64.8, 373.4 +/- 81.0 mm Hg; p < 0.05). Peak airway pressure was lower in groups III and IV than in group II (groups II, III, and IV: 19.7 +/- 0.8, 16.7 +/- 0.9. and 16.3 +/- 1.0 mm Hg; p < 0.05). Mean pulmonary arterial pressure in group III was lower than group II (groups II and III: 36.3 +/- 3.0 and 22.1 +/- 2.2 mm Hg; p < 0.01). Wet-dry weight ratio in group III was lower than in groups II and IV (group II, III, and IV: 5.2 +/- 0.2, 4.4 +/- 0.2, and 5.2 +/- 0.3; II vs III; p < 0.05, III vs IV; p < 0.01). Serum lipid peroxide levels in groups III and IV were significantly lower (groups II, III, and IV: 2.643 +/- 0.913, 0.455 +/- 0.147, and 0.325 +/- 0.124 nmol/ml; p < 0.01). CONCLUSION: VIP ameliorates reperfusion injury in an in vivo rat lung transplantation model. Either administration of VIP via the flush solution or systemically just after reperfusion was associated with improved pulmonary function.     

Polycentric total knee arthroplasty. A two-year follow-up study

Polycentric total knee arthroplasty provided significant relief of pain in 86 per cent of 500 knees. The independence and activity levels of the patients increased dramatically. The frequency of major complications as reflected by reoperation was 10 per cent in this series. There was a 2.8 per cent deep infection rate. One-third of the infected knees were salvaged and two-thirds required arthrodesis. Loosening of a component was noted in 2.4 per cent. After operation the average range of motion was from 6 to 101 degrees of flexion, for a range of 95 degrees; this was a 5-degree increase over average preoperative motion. Ninety-six per cent of the patients expressed satisfaction with the surgical result.     

Progression of radiolucent lines adjacent to the acetabular component and factors influencing migration after Charnley low-friction total hip arthroplasty

We analyzed the progression of radiolucent lines around the acetabular cup after 452 Charnley low-friction arthroplasties that had been performed in 392 patients between 1971 and 1976. The average duration of follow-up was twenty years (range, eleven to twenty-five years) for the 442 hips (382 patients) that had the original component in place at ten years. The demarcation of the bone-cement interface was classified according to the system of Hodgkinson et al. We sought to determine if there was a relationship between the progression of the radiolucent line and the age, gender, and weight of the patient; the level of activity; the preoperative diagnosis; or the amount of wear of the acetabular cup. The demarcation increased over time in 138 (31 per cent) of the 452 hips. Radiographs made at the time of the latest follow-up showed migration of eleven (5 per cent) of the 233 acetabular cups with no demarcation on the initial postoperative radiograph, eighteen (11 per cent) of the 167 cups with type-1 demarcation, twelve (35 per cent) of the thirty-four cups with type-2 demarcation, and thirteen of the eighteen cups with type-3 demarcation. Preoperative acetabular protrusion, inflammatory arthritis, and severe acetabular dysplasia as well as a previous operation were associated with the extent of the radiolucent line on the most recent radiograph (p < or = 0.05 for all). A high level of activity and more than two millimeters of wear of the acetabular cup also were related to the progression of the radiolucent line (p = 0.0004 and p < 0.0001, respectively). Kaplan-Meier survivorship analysis demonstrated that the greater the demarcation on the initial postoperative radiograph, the greater the risk of migration (p < 0.0001, Mantel-Cox test). Our data suggest that, after a Charnley low-friction arthroplasty, any cemented cup, even one with the least amount of demarcation (types 0 and 1), can migrate. As the type of the initial postoperative demarcation increases, so does the risk of migration of the cup, particularly when there is loss of the acetabular bone stock.     

A scale without anthropometric measurements can be used to identify low weight-for-age in children less than five years old

Malnutrition and morbidity have a synergistic association that often leads to death. However, malnutrition in children who die is largely underreported, because anthropometry of the deceased child is rarely known. This study had two purposes: i) to develop a scale that would help determine if a child had low weight-for-age (w/a), in the absence of anthropometric measures; and ii) to select an appropriate cut-off that would give the best sensitivity (Se) and specificity (Sp) of the proposed scale when contrasted with actual w/a measurement. The study was designed as a diagnostic test, and carried out in a rural area in central Mexico. We included 132 children under 5 y old with w/a under -2 Z score and 284 children with marginal or no w/a deficit as a control group. The proposed scale included potential predictive variables from clinical, socioeconomic and family factors. The best logistic regression model to predict low w/a included: birth weight less than 2,800 g, introduction of weaning foods after the sixth month of life, introduction of animal protein after the sixth month of life, low socioeconomic status, low w/a in siblings and more than three morbidity episodes in the previous 6 mon. Selecting a cut-off of 4 for this model to identify children with low w/a showed a Se and Sp of 85 and 95%, respectively. We tested the external validity of the scale in a different locale, and included 877 children under 5 y old from 10 rural communities. In this population, the scale showed Se of 84% and Sp of 81% to identify low w/a. Based on these results, we propose that the scale be included as a means of identifying low w/a in children who have died. We believe that this should be done in verbal autopsies, which, based on our previous research, the Ministry of Health adopted as part of the regular activities to monitor problems in the disease to health-seeking to death process.     

Comparison of functional performance after McKee-Farrar, Charnley, and Muller total hip replacement. A six-month follow-up of one hundred sixty-five cases

Measurements of functional performance were compared before and at 6 months after 58 McKee-Farrar, 50 Charnley, and 57 Muller total hip replacements in 143 patients. The measurment included: range of motion of the hip, hip abductor and adductor-muscle torque, weight-bearing activity during standing, forces applied to canes or crutches, and multiple components of walking performance. Each group of patients improved significantly after surgery in all of the components measured. Early postoperative differences among the 3 groups were found with respect to pain ratings, impressions of hip status, hip motions, muscle torque, the number of patients using assistive devices, and certain components of walking performance. There is nothing to suggest that the performance of any 1 group is distinctly better or worse than that of any other group 6 months after surgery. On the basis of average values, each group improved in every component of function and it is gratifying that, except for a few patients who developed postoperative infection, each patient could be considered to have successful reconstruction.     

Total hip arthroplasty with cement in patients who have rheumatoid arthritis. A minimum ten-year follow-up study

One hundred and six consecutive total hip arthroplasties with cement were performed by one surgeon, at least ten years before the time of the present clinical and radiographic review, in seventy-five patients who had adult-onset rheumatoid arthritis. Two patients (three hips) were lost to follow-up. Seven (7 per cent) of the remaining 103 hips were revised. The revisions were performed because of infection (three hips), dislocation (two hips), or aseptic loosening (two hips). Of the ninety-eight hips that were not lost to follow-up or revised because of infection or dislocation, eight (8 per cent) had radiographic loosening of the acetabular component and two (2 per cent) had radiographic loosening of the femoral component. Although the prevalence of radiographic loosening of the acetabular component was four times greater than the prevalence of radiographic loosening of the femoral component, the prevalence of revision because of aseptic loosening of the acetabular component was identical to that for the femoral component (one component each). These results compared favorably with those of total hip arthroplasty with cement, performed by the same surgeon, for the treatment of other diagnoses. Loosening of the acetabular component was significantly associated with a younger age at the time of the index operation (p = 0.03) and with acetabular osteolysis (p = 0.0006). Of forty-eight hips in thirty-two patients who survived for at least ten years, 96 per cent (forty-six hips) were considered by the patients to have a satisfactory result. At the time of the latest follow-up, twenty-four (75 per cent) of the patients had no pain in the hip. Although eighteen patients (56 per cent) could walk without support at a minimum of ten years after the operation, we found that the functional results for patients who had rheumatoid arthritis were inferior to those observed for patients who had had a total hip arthroplasty with cement, performed by the same surgeon, for the treatment of other diagnoses.     

Fixation of acetabular cups without cement in total hip arthroplasty. A comparison of three different implant surfaces at a minimum duration of follow-up of five years

OBJECTIVE: To investigate the roles of brain angiotensin II and C-type natriuretic peptide (CNP) in the hypertensive mechanism of deoxycorticosterone acetate (DOCA)-salt hypertension. METHODS: We injected 50 microg/kg CV-11 974, an angiotensin II type-1 receptors antagonist, 30 nmol/kg CNP-22, or the vehicle (artificial cerebrospinal fluid) into the cerebral ventricle or intravenously 5 min before the intracerebroventricular infusion of 1.5 mol/I NaCl solution for 30 min into either male normotensive Wistar rats or DOCA-salt hypertensive rats anesthetized with urethane, and their arterial pressures and heart rates were continuously recorded. Blood (2 ml) was collected at the end of the infusion for the measurement of plasma concentration of arginine vasopressin. We infused 10 or 50 microg/kg per day CV-11 974, 10 or 50 nmol/kg per day CNP-22, or the vehicle (1 microl/h) into the cerebral ventricles of DOCA-salt hypertensive rats for 7 days by using osmotic minipumps, and measured their systolic arterial pressures, pulse rates, and urinary excretions of vasopressin. RESULTS: Intracerebroventricular pre-administrations of CV-11 974 and of CNP-22 inhibited increases in mean arterial pressure, heart rate, and plasma vasopressin concentration induced by intracerebroventricular infusion of 1.5 mol/l NaCl into normotensive rats; increases in hemodynamics and plasma level of vasopressin induced by intracerebroventricular infusion of 1.5 mol/l NaCl were suppressed by intracerebroventricular pre-injections of CV-11 974, but not of CNP-22, into DOCA-salt hypertensive rats. Continuous intracerebroventricular infusions of 50 microg/kg per day CV-11 974 attenuated hypertension in DOCA-salt treated rats, accompanied by a reduction in urinary excretion of vasopressin. Continuous intracerebroventricular infusions of 50 nmol/kg per day CNP-22, however, affected neither hypertension nor urinary excretion of vasopressin in DOCA-salt hypertensive rats. CONCLUSION: Brain angiotensin II could play a role in the pressor mechanism of DOCA-salt hypertension by increasing release of vasopressin via type 1 receptors. That brain CNP has an inhibitory effect on release of vasopressin in acute experiments indicates that the impairment of this inhibitory effect of brain CNP on secretion of vasopressin could be involved in the pathogenesis of DOCA-salt hypertension in rats.     

Direct-exchange arthroplasty for the treatment of infection after total hip replacement. An average ten-year follow-up

The recirculation of naive lymphocytes from blood to lymph that is initiated in high endothelial venules (HEV) of secondary lymphoid organs such as lymph nodes and Peyer's patches (PP) is regulated by multiple interactions of adhesion receptor/counter-receptor pairs involving both selectins and integrins. We showed previously that blocking of only L-selectin is sufficient to ablate trafficking of naive CD4 cells and the development of their responses in peripheral lymph nodes but not in PP where alpha4beta7 integrins are thought to primarily regulate entry. However, although antibody to alpha4 integrins partially inhibited homing of naive CD4 cells to PP and not to lymph nodes, there was no effect on the development primary responses in these tissues or spleens. Since previous studies indicate that both alpha4beta7 integrins and L-selectin regulate adhesion of naive cells to PP HEV, we examined the effect a blockade of both adhesion pathways on the recirculation of naive CD4 cells. There was no detectable homing of naive CD4 cells to PP or lymph nodes when interactions with both receptors were inhibited, resulting in a profound depletion of naive CD4 cells and loss of antigen responses in these sites. In contrast, increased numbers of naive CD4 cells and responses of higher magnitude were found in the spleen. The results demonstrate recirculation of naive CD4 cells through tissues where entry is controlled through HEV is essential for the local generation of primary responses.     

Femoral cortical remodeling after uncemented total hip arthroplasty. A prospective radiologic study of 26 hips followed for 2 to 4 years

Aging and disease may make the elderly patient with cardiac disease particularly susceptible to hypotension during spinal anesthesia. We studied 15 men, 59-80 y old, with histories of prior myocardial infarction (n = 9), congestive heart failure (n = 2), and/or stable myocardial ischemia (n = 11) given spinal anesthesia with 50 mg lidocaine in dextrose. Technetium-99m-labeled red blood cell imaging estimated left ventricular ejection fraction (EF) and changes in blood volume in the abdominal organs and legs. Arterial and pulmonary artery catheters provided hemodynamic measurements. Sensory block averaged T4 (range T1-10). Mean arterial pressure decreased 33% +/- 15% (SD) (P < 0.001), secondary to decreases in vascular resistance (SVR), -26% +/- 13% (P < 0.001) and cardiac output, -10% +/- 16% (P = 0.03). EF increased from 53% +/- 11% to 58% +/- 14% (P < 0.001) while left ventricular end-diastolic volume (LVEDV) decreased (-19% +/- 9%, P < 0.001). Blood volume increased in the legs (6% +/- 6%, P = 0.006), kidneys (10% +/- 9%, P < 0.001), and mesentery (7% +/- 5%, P 0.001) but not in the liver or spleen. Cardiac function was well maintained. We concluded that the primary mechanism of hypotension was a decrease in SVR, not cardiac output, despite the decrease in LVEDV.     

Plasma lipids, HDL and apolipoproteins, and coronary heart disease in men less than 50 years old. A case-control study

Therapeutic interventions in the skeletal system are an essential part of interventional radiology. Although in terms of figures these procedures are applied less frequently, they are very effective. Percutaneous transarterial embolization of a spinal tumor is well-established interventional treatment. It is primary treatment for preoperative devascularization, but also for palliation of pain and for reduction of tumor volume. As an alternative access for embolization, direct percutaneous puncture of a vertebra is used. A new and promising technique is vertebroplasty, the percutaneous injection of acrylic surgical cement in destroyed vertebrae. The present paper discusses indications, technique, results and complications of these interventional therapeutic modalities in the treatment of primary and secondary spinal tumors.