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E A Salvati

Publications and source records attributed to E A Salvati.

At least 19 recordsLinked to original sources
PubMed2001

Effective bactericidal activity of tobramycin and vancomycin eluted from acrylic bone cement.

We studied the bioactivity of vancomycin and tobramycin eluted from methylmethacrylate bone cement. Aliquots of the drainage were obtained at 1, 6, 12 and 24 hours following total hip prosthetic implantation with vancomycin-tobramycin-loaded cement in 3 patients. The samples were analyzed with fluorescence polarization immunoassay and bioassay, using group B streptococcus for vancomycin and Escherichia coli for tobramycin. These bacteria were selected due to the effectiveness of vancomycin and poor effectiveness of tobramycin against group B streptococcus and conversely with E. coli. The immunodetection of vancomycin averaged 14 (1 hour), 9 (6 hours), 10 (12 hours) and 11 microg/mL (24 hours). The bioassay averaged 47, 36, 79 and 41 microg/mL (p = 0.03). The immunodetection of tobramycin averaged 43, 21, 18 and 14 microg/mL; and bioassay 30, 15, 15 and 12 microg/mL (p = 0.1). Both antibiotics eluted with a highly effective bactericidal activity. Our findings indicate that the presence of tobramycin has a synergistic-like effect on the bactericidal activity of vancomycin, which has not been previously reported. We recommend a combination of vancomycin and tobramycin with cement for the treatment of orthopedic infections caused by gram-positive organisms.

Aged↗
PubMed2001

Inflatable pillows as axillary support devices during surgery performed in the lateral decubitus position under epidural anesthesia.

UNLABELLED: The lateral decubitus position can cause dependent shoulder discomfort or result in traction on the brachial plexus. We measured pressure beneath the dependent shoulder and lateral angulation of the cervical spine in patients positioned in the lateral decubitus position for total hip replacement under epidural anesthesia. Inflatable pillows (Shoulder-Float) beneath the chest wall and head reduced pressure beneath the dependent shoulder from 66 to 12 mm Hg (P < 0.001) and lateral angulation of the cervical spine from 14 degrees to 4 degrees (P < 0.001). In a randomized crossover study of a further 15 patients, the use of inflatable pillows resulted in significantly less pressure beneath the dependent shoulder and chest wall than either a gel-pad or a 1000-mL lactated Ringer's bag. Inflatable pillows placed beneath the chest wall and head in the lateral decubitus position provided lower pressure beneath the dependent shoulder than other support devices and facilitated alignment of the cervical spine. IMPLICATIONS: When patients lie on their side, this results in pressure beneath the shoulder and tilting of the head and neck to one side. These problems were effectively corrected with an inflatable pillow (Shoulder-Float).

Adult↗
PubMed2001

Pigmented villonodular synovitis of the hip: 2- to 23-year followup study.

Pigmented villonodular synovitis affecting the hip is rare. Seven new patients are presented and 117 cases from the literature are reviewed. Among the new patients, two refused treatment; in one patient, severe bone loss was observed after a radiographic followup of 21 years; the second patient showed no radiographic changes 2 years after diagnosis. One patient underwent a synovectomy and had a recurrence 9 years later, requiring a total hip replacement. The remaining four patients underwent synovectomy and primary total hip replacement with no recurrences detected after an average followup of 13 years (range, 2-23 years). Among 117 cases published, 62 patients (53%) did not have enough information for analysis. A metaanalysis using the remaining 55 patients was done. In nine patients (16%; nine of 55) the diagnosis was made with a preoperative biopsy. Treatment consisted of synovectomy in 26 patients (47%; 26 of 55), arthroplasty in 24 (43%; 24 of 55), arthrodesis in two (4%; two of 55), and hindquarter amputation in a patient misdiagnosed as having synovial sarcoma (2%; one of 55). Two patients (4%; two of 55) were not treated. Ten patients had a recurrence (19%; 10 of 53); nine in the synovectomy group (35 %; nine of 26) and one in the joint replacement group (4%; one of 24). Synovectomy is recommended for patients with preserved articular cartilage and total hip replacement is recommended for patients with secondary osteoarthritis. Removal of all macroscopic tumors including careful curetting of the osteolytic lesions should be done as they may constitute a source of recurrence.

Follow-Up Studies↗
PubMed2001

The effect of preoperative donation of autologous blood on deep-vein thrombosis after total hip arthroplasty.

We have assessed the effect of the donation of autologous blood and the preoperative level of haemoglobin on the prevalence of postoperative thromboembolism in 2043 patients who had a total hip arthroplasty. The level of haemoglobin was determined seven to ten days before surgery and all patients had venography of the operated leg on the fifth postoperative day. The number of patients who had donated autologous blood (1037) was similar to that who had not (1006). A significant decrease in the incidence of deep-vein thrombosis (DVT) was noted in those who had donated blood preoperatively (9.0%) compared with those who had not (13.5%) (p = 0.003). For all patients, the lower the preoperative level of haemoglobin the less likely it was that a postoperative DVT would develop. Of those who had donated blood, 0.3% developed a postoperative pulmonary embolism compared with 0.7% in those who had not, but this difference was not statistically significant. No significant difference was found in the requirements for transfusion between the two groups.

Aged↗
PubMed2001

Bone density adjacent to press-fit acetabular components. A prospective analysis with quantitative computed tomography.

BACKGROUND: The status of periprosthetic bone stock is an important concern when revision total hip arthroplasty is undertaken. Remodeling of periprosthetic femoral bone after total hip arthroplasty has been studied extensively, and the phenomenon of femoral stress-shielding has been well characterized. Finite element analysis and computer-simulated remodeling theory have predicted that retroacetabular bone-mineral density decreases after total hip arthroplasty; however, remodeling of periprosthetic pelvic bone in this setting has yet to be well defined. This study was conducted to evaluate the short-term natural history of periacetabular bone-mineral density following primary total hip arthroplasty. METHODS: Periacetabular bone-mineral density was studied prospectively in a group of twenty-six patients who underwent primary hybrid total hip arthroplasty for the treatment of advanced osteoarthritis. Density within the central part of the ilium (directly cephalad to a press-fit acetabular component) was assessed with serial quantitative computed tomography. Baseline density was measured within the first five days following the total hip arthroplasty. Ipsilateral density measurements were repeated at an average of 1.28 years postoperatively. Density values at corresponding levels of the contralateral ilium were obtained at both time-points in all patients to serve as internal controls. RESULTS: Bone-mineral density decreased significantly (p< or =0.001) between the two time-points on the side of the operation. The mean absolute magnitude of the interval density reduction (75 mg/cc) was greatest immediately adjacent to the implant (p<0.001), but it was also significantly reduced (by 35 mg/cc) at a distance of 10 mm cephalad to the implant (p = 0.001). Relative declines in mean density ranged from 33% to 20% of the baseline values. No focal bone resorption (osteolysis) was detected at the time of this short-term follow-up study. With the numbers available, no significant interval alteration in bone-mineral density was found on the untreated (internal control) side (p> or =0.07). CONCLUSIONS: We suggest that the observed decline in bone-mineral density represents a remodeling response to an altered stress pattern within the pelvis that was induced by the presence of the acetabular implant. This finding corroborates the predictions of finite element analysis and computer-simulated remodeling theory. It remains to be seen whether this trend of atrophy of retroacetabular bone stock will continue with longer follow-up or will ultimately affect the long-term stability of press-fit acetabular components.

Acetabulum↗
PubMed2001

Dislodgment of polyethylene liners in first and second-generation Harris-Galante acetabular components. A report of eighteen cases.

BACKGROUND: Dislodgment of the polyethylene liner is an increasingly common complication following total hip arthroplasty. The purposes of this study are to present the results in a series of patients with this complication and to analyze the mode of failure. METHODS: Between November 1995 and January 2001, eighteen patients who had had a total hip arthroplasty presented with dislodgment of the polyethylene liner from a Harris-Galante metal acetabular shell. The medical records, radiographs, operative notes, and retrieved components were reviewed. In addition, scanning electron microscopy was used to study the fractured surfaces in a shell that had four broken tines. RESULTS: The components had been in situ for an average of seven years (range, three to eleven years). Seventeen components were second generation, and one was first generation. Symptoms developed spontaneously in sixteen patients, during sexual intercourse in one, and following a fall on the hip in one. Radiographs showed eccentric positioning of the head in all of the hips and broken tines in six. All of the shells were well fixed. Treatment consisted of revision of the shell in four patients, exchange of the liner in four, cementation of a new liner into the shell in seven, and cementation of an all-polyethylene cup in three. The liners had severe damage of the rim. Scanning-electron microscopy of the fractured surfaces of four tines revealed a fatigue pattern. CONCLUSIONS: We believe that, as the liner wears and becomes loose because of an inadequate locking mechanism, progressive micromotion occurs and the load increases on the polyethylene rim until it deforms and/or fractures. Subsequently, nothing prevents the liner from rotating out of the shell. As this mechanism of failure appears to include fatigue failure of the locking tines and wear of the liner, this complication is likely to increase as the components age in situ.

Acetabulum↗
PubMed2000

Warfarin-associated intracapsular hemorrhage causing an acutely painful total hip arthroplasty: a rare complication of prolonged anticoagulant therapy.

Hemorrhage is the most prevalent adverse effect of oral anticoagulant therapy. The incidence of bleeding complications is related to the duration and range of therapy. A patient on long-term warfarin anticoagulation developed a spontaneous intracapsular bleed into a total hip arthroplasty that had been implanted 11 years before. Joint aspiration allowed early recognition with immediate resolution of symptoms. Diagnosis and treatment of this rare complication are discussed with a review of the literature.

Aged↗
PubMed2000

Pneumatic compression hemodynamics in total hip arthroplasty.

A crossover study was performed to evaluate the effect of several pneumatic compression devices and active dorsoplantar flexion in 10 patients who underwent total hip arthroplasty. Using the Acuson 128XP/10 duplex ultrasound unit with a 5-MHz linear array probe, peak venous velocity and venous volume were assessed above and below the greater saphenous vein and common femoral vein junction. A computer generated randomization table was used to determine the order of the test conditions. The pneumatic compression devices evaluated included two foot pumps, one foot and calf pump, one calf pump, and three calf and thigh pumps. Statistical analyses included analysis of variance and analysis of variance with covariance between devices and patients. The covariates tested were the baseline measurements and the order in which the devices were tested. Differences between devices relate in part to the frequency and rate of inflation and the location and type of compression. Pulsatile calf and foot and calf pneumatic compression with a rapid inflation time produced the greatest increase in peak venous velocity, whereas compression of the calf and thigh showed the greatest increase in venous volume. Because patient and nursing compliance is essential to the success of mechanical prophylaxis for thromboembolic disease, the more simple, yet efficacious, devices that are easier to apply and less cumbersome appear to have a greater likelihood of success. In the active and alert patient, active dorsoplantar flexion should be encouraged.

Arthroplasty, Replacement, Hip↗
PubMed2000

The safety and efficacy of intraoperative heparin in total hip arthroplasty.

A single dose of unfractionated heparin (15 U/kg), administered intravenously before surgery on the femur suppresses thrombogenesis during total hip replacement. Nine hundred eighty-nine patients (1021 hips) who received one dose of intraoperative heparin with hypotensive epidural anesthesia were followed up prospectively for 3 months. Asymptomatic deep vein thrombosis assessed by ultrasound in the first 198 consecutive patients showed an incidence of 7.1% (14 of 198). The incidence of clinical deep vein thrombosis in the subsequent 791 patients was 0.88% (seven of 791). Symptomatic pulmonary embolism occurred in 0.5% (five of 989). No patients died and there was one major bleeding episode. Based on this favorable experience, intraoperative heparin appears safe and efficacious as thromboembolic prophylaxis.

Adult↗
PubMed1999

The arthroscopic drainage, irrigation, and débridement of late, acute total hip arthroplasty infections: average 6-year follow-up.

We present our experience with arthroscopy for the treatment of late, acute periprosthetic hip infections in 8 consecutive patients, treated from 1989 to 1994. After a hip aspiration confirmed the presence of bacterial infection, all patients underwent prompt arthroscopic treatment, which consisted of drainage, lavage, and debridement. Postoperatively, patients were given 2 to 6 weeks of intravenous antibiotics, followed by long-term oral antibiotic suppression. At a mean follow-up of 70 months (range, 29-104 months), no recurrence of infection occurred. No progressive radiographic loosening was noted. Based on this initial study, we believe that arthroscopic irrigation and debridement can benefit well-selected patients who suffer late, acute hip periprosthetic infections. Effective treatment requires early diagnosis, prompt arthroscopic debridement, well-fixed components, a sensitive microorganism, and patient tolerance to and compliance with the antibiotic therapy.

Acute Disease↗
PubMed1999

The incidence of venous thromboembolism after total hip arthroplasty: a specific hypotensive epidural anesthesia protocol.

We retrospectively reviewed all consecutive unilateral primary total hip arthroplasty (THA) procedures performed by 3 attending surgeons on the Arthroplasty Service at our institution from January 1, 1990, to December 31, 1993. All surgery was performed under a specific hypotensive epidural anesthesia protocol. Hypotensive epidural anesthesia at our institution provides a lower level of hypotension (mean arterial pressure of 50-60 mmHg) as compared to hypotensive anesthesia used more generally around the world (mean arterial pressure >70 mmHg). For each patient, hospital and postdischarge office records for a minimum of 3 months after surgery were reviewed for the type of postoperative screening test, the incidence of deep venous thrombosis (DVT), and the incidence of symptomatic pulmonary embolism (PE). Overall, 2,592 primary unilateral THAs were performed with 78.6% (2,037 of 2,592) of patients receiving a venogram. Our protocol for thromboembolic disease prophylaxis in these patients included aspirin postoperatively as well as antithromboembolic disease stockings and early ambulation (24-48 hours postoperatively). The 555 patients who did not receive venography were managed with a different protocol that included warfarin postoperatively as well as antithromboembolic disease stockings and early ambulation. This high-risk group consisted of patients who received warfarin preoperatively (ie, cardiac valve) or patients with a history of DVT who were to receive warfarin postoperatively, regardless of venography result. Overall, DVT was diagnosed in 10.3% (210 of 2,037) of patients who had a venogram. Of these patients who had venography, 2.3% (46 of 2,037) had an isolated proximal DVT; 6.0% (123 of 2,037), a distal DVT; and 2.0% (41 of 2,037), both a proximal and a distal DVT. Of the 87 cases of proximal DVT identified, 60.9% (53 of 87) were femoral DVT; 18.4% (16 of 87), popliteal DVT; and 20.7% (18 of 87), both femoral and popliteal DVT. Of the 164 distal DVT, 68.3% (112 of 164) were major calf DVT and 31.7% (52 of 164) were minor calf DVT. The overall incidence of major venous thrombosis (sum of proximal and major calf thrombi) was 9.8% (199 of 2,037) in patients who had venography. Ventilation-perfusion scanning was used selectively in patients symptomatic for PE. Overall, symptomatic PE was diagnosed by ventilation-perfusion scan in 1.0% (26 of 2,592) of patients, with 0.58% (15 of 2,592) of patients having an in-hospital PE. Of the 15 patients who had an in-hospital PE, 11 patients had a venogram, and only 3 of 11 were positive. Late symptomatic PE was defined from discharge (mean, 7 +/- 2 days) to 3 months after discharge from the hospital and occurred in 0.42% (11 of 2,592) of patients. One of the 11 late symptomatic PEs was fatal. In the overall study, this represents 0.04% (1 of 2,592) fatal PE. Of the 11 patients with a late symptomatic PE, 10 had venograms in the hospital, and all 10 were negative for DVT. Overall, in the patients with a positive venogram, the incidence of symptomatic PE was 1.4% (3 of 210), whereas in the patients with a negative venogram, the incidence of symptomatic PE was 0.44% (8 of 1,827). At our institution, patients who undergo primary THA performed with hypotensive epidural anesthesia, postoperative aspirin, antithromboembolic disease stockings, and early ambulation have a low risk for thromboembolic disease.

Anesthesia, Epidural↗
PubMed1999

Dose response of intravenous heparin on markers of thrombosis during primary total hip replacement.

BACKGROUND: Thrombogenesis in total hip replacement (THR) begins during surgery on the femur. This study assesses the effect of two doses of unfractionated intravenous heparin administered before femoral preparation during THR on circulating markers of thrombosis. METHODS: Seventy-five patients undergoing hybrid primary THR were randomly assigned to receive blinded intravenous injection of either saline or 10 or 20 U/kg of unfractionated heparin after insertion of the acetabular component. Central venous blood samples were assayed for prothrombin F1+2 (F1+2), thrombin-antithrombin complexes (TAT), fibrinopeptide A (FPA), and D-dimer. RESULTS: No changes in the markers of thrombosis were noted after insertion of the acetabular component. During surgery on the femur, significant increases in all markers were noted in the saline group (P < 0.0001). Heparin did not affect D-dimer or TAT. Twenty units per kilogram of heparin significantly reduced the increase of F1+2 after relocation of the hip joint (P < 0.001). Administration of both 10 and 20 U/kg significantly reduced the increase in FPA during implantation of the femoral component (P < 0.0001). A fourfold increase in FPA was noted in 6 of 25 patients receiving 10 U/kg of heparin but in none receiving 20 U/kg (P = 0.03). Intraoperative heparin did not affect intra- or postoperative blood loss, postoperative hematocrit, or surgeon's subjective assessments of bleeding. No bleeding complications were noted. CONCLUSIONS: This study demonstrates that 20 U/kg of heparin administered before surgery on the femur suppresses fibrin formation during primary THR. This finding provides the pathophysiologic basis for the clinical use of intraoperative heparin during THR.

Aged↗
PubMed1998

Effect of increasing temperature on the properties of four bone cements.

This investigation uses a laboratory model to evaluate the effects of a heated femoral stem on the biomechanical properties of four common acrylic bone cements. American Society for Testing Materials dog bone shaped acrylic cement specimens made at four test temperatures, 0 degree C, 23 degrees C, 37 degrees C and 50 degrees C, were tested for modulus, ultimate tensile strength, fracture toughness, and percent porosity. Fatigue strength was tested in Simplex P at 23 degrees C and 37 degrees C. The data allow direct comparison among four cement brands at each of the four temperature conditions. No adverse changes of the mechanical properties were found for any cement at any temperature. Modulus, fracture toughness, and fatigue strength were unaffected by increased temperature. Ultimate tensile strength increased in Simplex P and Zimmer Osteobond but was unaffected for Zimmer Regular and Palacos R cements. Percent porosity was related to temperature changes inversely in all brands studied, except for Palacos R which consistently had low porosity, unaffected by temperature variation. Fatigue strength of Simplex P was unaffected by heating to 37 degrees C. Based on this laboratory model, heating of the femoral stem could save time without sacrificing mechanical properties of acrylic bone cement.

Biomechanical Phenomena↗
PubMed1998

Enhancement of bone formation in the setting of repeated tissue deformation.

The purpose of this study was to investigate whether the osteoinductive recombinant human bone morphogenetic protein 2, combined with a collagen carrier, could enhance bone formation when exposed to controlled amounts of tissue deformation. Chambers that allow for the multiple harvestings of tissue specimen were used. The devices were implanted in the tibial metaphyses of skeletally mature New Zealand White rabbits. A tissue ingrowth canal in each device either was left empty or filled with a collagen carrier with or without 0.6 microgram of recombinant human bone morphogenetic protein 2. The tissue ingrowth canal was deformed cyclically during a period of 2 minutes daily, according to a previously described deformation protocol. The tissue that developed in the chambers was harvested every 3 weeks. Undecalcified histologic sections of each tissue sample were stained with trichrome and von Kossa stains and subjected to histomorphometric analysis. It was found that deformation decreased the area occupied by bone trabeculae in the empty chambers and carrier controls. The amount of bone formed in the chambers treated with bone morphogenetic protein 2 was significantly greater than that in the chambers subjected to micromotion and left empty or implanted with the collagen carrier. The amount of bone in chambers with motion and bone morphogenetic protein 2 was equal to that in chambers left empty and not subjected to micromotion. Qualitative histologic analysis of the bone formed with bone morphogenetic protein 2 revealed normal bone trabeculae. These findings indicate that bone morphogenetic protein 2 may be useful in augmenting bone formation in conditions that otherwise would favor the formation of fibrous tissue.

Animals↗
PubMed1998

Role of polyethylene oxidation and consolidation defects in cup performance.

Quality factors such as particle consolidation and oxidation have been claimed to impair the performance of ultrahigh molecular weight polyethylene implants, but no definite data estimate their real effect. To assess the influence of these quality determinants in wear, wear rate, and time in service at a single, well proven design, the percentage area of polyethylene sections occupied by nonconsolidated polyethylene particles, the presence of a white band, and the amount of polyethylene oxidation (through density curves) were evaluated in 92 retrieved Charnley acetabular components with available clinical data. The average percentage area of nonconsolidated polyethylene particles in cup sections was 3.1%. There were 11 cups showing a subsurface white band. The authors observed an average density in the deep polyethylene of 0.9420 g/cc after an average in vivo use of 9.8 years (range, 0.08-20.3 years). Banded cups showed significantly higher subsurface densities. When studying the relationship among clinical and material factors with performance variables, wear measurements (obtained through radiographic methods and direct measurements of polyethylene thickness in the collected implants) correlated with age at implantation, activity, and time in service. Weight was a determinant of the wear rate. None of the studied polyethylene quality factors showed a definite association with wear performance or time to failure in this series. Implant survivorship was not significantly impaired in the 22.225-mm Charnley low friction replacement by a subsurface white band or by a higher area occupied by nonconsolidated particles. Fewer nonconsolidated particles were not associated with longer survivorship. This design proved tolerance to polyethylene quality variations, in the signaled ranges, without a significant effect in the system performance.

Arthroplasty, Replacement, Hip↗
PubMed1997

Patients' expectations and satisfaction with total hip arthroplasty.

Although there have been many studies focusing on the increasingly important assessment of patients' satisfaction, few studies have specifically addressed this tissue for total hip arthroplasty (THA). The goals of this study were to measure patients' satisfaction with THA and to evaluate the relationships of expectations and outcome to patients' satisfaction. A total of 180 patients were surveyed 2 to 3 years after THA about their experiences with THA. Patients cited 45 different expectations, which were grouped into five categories reflecting improvement in pain, walking, psychological state, essential activities, and nonessential activities. Overall, 89% of patients were satisfied with the results of surgery. Lower rates of satisfaction were found in patients who had a better preoperative condition (as measured by the surgeons with The Hospital for Special Surgery Hip Scale), in patients who expected improvement in nonessential activities, and in patients who reported worse postoperative condition (as measured by self-assessment with the Hip Rating Questionnaire and the Medical Outcomes Study Short-form General Health Survey). Patients were also asked how they came to THA. Nearly 50% of patients were first referred to an orthopaedist by family or friends or based on their own knowledge. Seventy-four percent either had subsequently referred others for THA or would have done so if they knew someone with hip pain. This study demonstrates that satisfaction with THA is a complex phenomenon, affected by expectations, outcome, and what patients know about the procedure from their community network. A better understanding of THA satisfaction will enable better future selection of patients and an additional dimension of outcome, both of which are important to patients and payers.

Adolescent↗
PubMed1997

Effect of epidural analgesia on venous blood flow after hip arthroplasty.

The effects of postoperative epidural infusions using local anesthetic and narcotic were assessed in reference to lower extremity blood flow. Nineteen patients who underwent unilateral total hip arthroplasty were randomly assigned to receive a postoperative epidural infusion of either 5 microg/ml fentanyl or 5 microg/ml fentanyl plus 0.125% bupivacaine at a rate of 10 ml per hour. The infusions were started after complete resolution of the operative epidural blockade. Femoral venous blood flow volume and velocity were measured above and below the saphenous vein bifurcation using an Acuson #128XP/10 computed sonography system (duplex ultrasound) and proprietary software. Femoral venous blood flow was not affected by the type of infusion and did not increase during the study period. However, femoral venous blood flow volume increased 50% after active flexion and extension of the foot, 10 times in quick succession. The addition of bupivacaine (a local anesthetic that blocks sympathetic afferent nerves) to a postoperative epidural infusion does not augment blood flow from the deep veins of the leg after total hip arthroplasty. Alternatively, lower extremity skeletal muscle activity significantly enhances femoral venous blood flow and may be a useful adjunct in deep venous thrombosis prevention.

Aged↗