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41.
Between 1999 and 2005, we treated 41 patients with a total hip arthroplasty for failed fixation of a hip fracture. This study had three purposes: (1) to determine the reason/s for fixation failure (2) to record difficulties/complications encountered in converting to a salvage arthroplasty and (3) to compare the outcome of these patients (Group 1) with a matched group of patients who underwent a primary hip arthroplasty (Group 2). Failure to achieve a good reduction and optimal screw placement was evident in 80% of cases of failed fixation. A high incidence of complications was recorded in the perioperative period during conversion to a salvage arthroplasty. Functional outcome was statistically inferior in Group1; this group also had a higher incidence of complications. Radiographs at 2 years postoperatively showed evidence of femoral stem loosening in 16% of the salvage group compared with 3% in the primary hip arthroplasty group.  相似文献   
42.
This study examined predictors of employment among substance-using men and women enrolled in welfare-to-work programs. Participants were 394 welfare applicants assigned to either coordinated care management or usual care for treatment services and job training and followed up for 1 year to track employment outcomes. Common barriers to work were assessed at baseline in four key domains: disabilities, situational barriers, labor capital, and motivation. Results indicated substantial gender differences in the number and profile of work barriers. Among men, work experience and job motivation were the only significant predictors of employment; among women, multiple factors from each barrier domain predicted job acquisition even when controlling for all other significant predictors. Findings suggest that welfare-to-work programs should emphasize job training and job seeking during the early stages of welfare interventions for men and for many women.  相似文献   
43.
Leptin is important in a wide range of physiological processes, but logistical constraints associated with venipuncture blood collection have limited research on leptin in diverse, community-based settings. The aim of this short report is to present and validate an enzyme immunoassay method for quantifying leptin in samples of capillary whole blood collected from a simple finger prick and dried on filter paper. The method was evaluated through analysis of precision, reliability, stability, and comparisons with matched plasma and blood spot samples. We report acceptable levels of assay precision and reliability, and good agreement between results obtained from matched plasma and blood spot samples (r = 0.976, P < 0.001). Leptin concentrations begin to deteriorate after only 3 days at room temperature. Thus, care should be taken to refrigerate or freeze samples promptly. The relative ease of blood spot sample collection may facilitate research on leptin in a wider range of cultural and ecological settings.  相似文献   
44.
OBJECTIVE: To compare effectiveness of two techniques for removing football face masks: cutting loop straps [cutting tool: FMXtractor (FMX)] or removing screws with a cordless screwdriver and using the FMXtractor as needed for failed removals [combined tool (CT)]. Null hypotheses: no differences in face mask removal success, removal time or difficulty between techniques or helmet characteristics. DESIGN: Retrospective, cross-sectional. SETTING: NOCSAE-certified helmet reconditioning plants. PARTICIPANTS: 600 used high school helmets. INTERVENTIONS: Face mask removal attempted with two techniques. MAIN OUTCOME MEASUREMENTS: Success, removal time, rating of perceived exertion (RPE). RESULTS: Both techniques were effective [CT 100% (300/300); FMX 99.4% (298/300)]. Use of the backup FMXtractor in CT trials was required in 19% of trials. There was significantly (P<0.001) less call for the backup tool in helmets with silver screws (6%) than in helmets with other screws (31%). Mean removal time was 44.51+/-18.79s (CT: 37.84+/-15.37s, FMX: 51.21+/-19.54s; P<0.001). RPE was different between techniques (CT: 1.83+/-1.20, FMX: 3.11+/-1.27; P<0.001). Removal from helmets with silver screws was faster (Silver=33.38+/-11.03, Others=42.18+/-17.64; P<0.001) and easier (Silver=1.42+/-0.89, Other=2.23+/-1.33; P<0.001). CONCLUSIONS: CT was faster and easier than FMX. Most CT trials were completed with the screwdriver alone; helmets with silver screws had 94% screwdriver success. Clinically, these findings are important because this and other research shows that compared to removal with cutting tools, screwdriver removal decreases time, difficulty and helmet movement (reducing potential for iatrogenic injury). The combined-tool approach captures benefits of the screwdriver while offering a contingency for screw removal failure. Teams should use degradation-resistant screws. CLINICAL RELEVANCE: Sports medicine professionals must be prepared with appropriate tools and techniques to efficiently remove the face mask from an injured football player's helmet.  相似文献   
45.
Ankle fusion: a retrospective review   总被引:1,自引:0,他引:1  
A D Aaron 《Orthopedics》1990,13(11):1249-1254
The results of ankle fusion were reviewed in 26 patients who underwent 32 arthrodesis procedures. Posttraumatic degenerative arthritis was the most common indication for fusion (54%). Crossed cancellous screws were the primary method employed (43%), with an external fixator being used in 22% of cases. The overall union rate was 81%, with both crossed cancellous screws and external fixation attaining the best results (86%). Nonunion and infection were the most frequent complications. Progression of subtalar arthritis was demonstrated in 29% of patients postoperatively. Seventy-eight percent of patients graded extremity appearance as excellent or good, with the majority being able to return to work.  相似文献   
46.
OBJECTIVE: To determine clinical utility of fine needle aspiration (FNA) in parotid neoplasia. STUDY DESIGN AND SETTING: Retrospective cohort study. METHODS: FNA and final pathology data were reviewed for patients who underwent parotidectomy for malignancy. Surgical outcomes were compared between patients with malignant cytology versus nonmalignant/nondiagnostic cytology. RESULTS: Twenty-seven of 33 primary malignant parotid lesions underwent FNA. Seventeen (63.0%) patients were diagnosed with cancer on FNA. The remaining 16 patients did not undergo FNA (n = 6), had a nondiagnostic FNA specimen (n = 5), or were incorrectly diagnosed with a benign lesion (n = 5). Patients who went on to parotidectomy with intent to treat malignancy based on FNA had significantly higher rates of upfront neck dissections (47.1% vs 12.5%, P = 0.036) as well as clear pathological margins (70.6% vs 31.3%, P = 0.027) vs those with nonmalignant FNA diagnoses. CONCLUSIONS: Preoperative FNA diagnosis of malignancy improves surgical treatment of parotid cancer. SIGNIFICANCE: FNA in the evaluation of parotid masses should strongly be considered.  相似文献   
47.
Zusammenfassung Operationsziel überdachung des Femurkopfes bei Hüftgelenkdysplasie. Indikationen Dysplastisches Acetabulum bei Patienten mit neuromuskul?ren und nichtneuromuskul?ren Erkrankungen. übergro?es, flaches Acetabulum. Fehlen einer lateralen und kranialen überdachung. Kontraindikationen Y-Fuge geschlossen, Wachstum abgeschlossen. Stark verformter Femurkopf. Operationstechnik Modifizierter Zugang nach Salter/Smith-Petersen. Freilegung und Teilung der Apophyse des Beckenkammes mit einem Messer. Freilegung der Darmbeinschaufel. Osteotomie der ?u?eren Wand des Iliums; sie wird vorsichtig mit Hilfe eines gebogenen mei?els nach unten gebogen und in dieser Stellung durch Einsetzen von trikortikalen Beckenkammsp?nen gehalten. Eine Osteosynthese ist nicht notwendig. Becken-Bein-Gipsverband mit Einschlu? des gegenseitigen Oberschenkels für sechs Wochen. Ergebnisse Zwischen 1987 und 1997 wurden 26 Hüften von 23 Patienten operiert. überwiegend handelte es sich um Kinder mit spastischen Paresen. Folgende zus?tzliche Eingriffe wurden vorgenommen: Offene Reposition zehnmal, Femurosteotomie 18mal und Tenotomien sowie Muskelabl?sungen 15mal. Der Durchschnittswert des azetabul?ren Index verbesserte sich von 32° auf 22°, der durchschnittliche Wert des Kopfzentrum-Pfannenrand-Winkels von −25° auf 22° und der durchschnittliche Migrationsindex von 62% auf 69%. Als Komplikationen wurden beobachtet: eine erneute Subluxation, ein frühzeitiger Verschlu? des Y-Knorpels, eine Fraktur des anderen Femur, einmal heterotope Ossifikationen und einmal eine Infektion der Harnwege.  相似文献   
48.
49.
A boy aged 4.5 years with prune-belly syndrome (PBS) and associated urethral stenosis, oligohydramnios, imperforate anus and vesicosigmoid fustula is described. In contrast to the anticipated poor prognosis, vesicostomy and divided transverse colostomy performed after birth followed by prophylaxis of infection and bicarbonate supplementation have resulted in a good outcome. The vesicosigmoid fistula might have served in utero as a natural diversion protecting from pressure-induced renal damage. It is suggested that the main determinant of prognosis in PBS is the presence and degree of kidney dysplasia at birth as reflected by the neonatal renal function after performance of an indicated urinary diversion procedure rather than the presence of severe associated anomalies.Supported in part by grants from the National Institute of Health AM 37223-01 and the Medical School and Graduate School Research Committees of the University of Wisconsin and a Research Career Development Award KO4 AM 00421 (RWC), by the Pearl M. Stetler Foundation (SD) and by a National Kidney Foundation fellowship (IZ)  相似文献   
50.
C E Thompson  L E Damon  C A Ries  C A Linker 《Blood》1992,80(8):1890-1895
We reviewed the medical records of 44 adults with 50 consecutive episodes of thrombotic thrombocytopenia purpura (TTP) or hemolytic uremic syndrome (HUS) seen at the University of California, San Francisco affiliated hospitals during the past decade. Patients were treated according to a uniform plan in which initial therapy included daily large volume plasmapheresis using fresh frozen plasma. Patients not responding completely to initial therapy were treated with a salvage regimen including splenectomy, dextran, and corticosteroids. At the time of diagnosis, the lactate dehydrogenase (LDH) was elevated in 98% of cases, with a median value of 1,208 U/L. Other clinical features were present inconsistently, and only 34% of "TTP" episodes involved the classic pentad of hemolytic anemia, thrombocytopenia, neurologic disorders, noninfectious fever, and renal impairment. Primary treatment with plasma exchange produced complete remission in 56% (27 of 48) of the episodes. Previously splenectomized patients uniformly responded to plasma therapy (12 of 12). In patients not responding completely to primary therapy, salvage splenectomy produced complete responses in 81% (13 of 16) of the cases. The pattern of clinical response to therapy was consistent, with initial resolution of neurologic dysfunction (median, 3 days) followed by normalization of LDH levels (5 days) and platelet count (7 days). Normalization of renal function occurred significantly later (15 days). Although short-term responses to plasma therapy in human immunodeficiency virus (HIV)-seropositive patients did not differ from other patients, no HIV-positive patient survived more than 2 years from diagnosis of thrombotic microangiopathy (TMA). We conclude that the diagnosis of TMA requires a high degree of clinical suspicion and that the diagnostic criteria should consist of microangiopathic hemolytic anemia, thrombocytopenia, and an elevated LDH. Initial therapy with plasma exchange leads to disease control in the majority of cases, but an optimal treatment strategy requires the use of alternative methods if initial remission is transient or not achieved. Salvage therapy with splenectomy, steroids, and dextran is highly effective in this setting.  相似文献   
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