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81.
Patellofemoral pain is a frequent and often challenging clinical problem. It affects females more than males and includes many different pathologic entities that result in pain in the anterior aspect of the knee. Diagnosis of the specific cause of pain can be difficult and requires assessment of lower extremity strength, alignment, and range of motion, as well as specific patella alignment, tracking, and mobility. The treatment for patellofemoral pain is usually conservative with anti-inflammatory medications, activity modification, and a specific physical therapy program focusing on strengthening and flexibility. Infrequently, surgical treatment may be indicated after a non-operative program fails. The outcomes of surgical management may include debridement, lateral release, and realignment of the extensor mechanism to unload the patellofemoral articulation are favorable.  相似文献   
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Objective The objective was to evaluate the findings and diagnostic accuracy of ultrasound in antero-lateral ankle impingement (ALI) with clinical and arthroscopic correlation. Design and patients Seventeen elite footballers with chronic ankle pain were referred for ultrasound with a clinical diagnosis of ALI (n = 8) or a control condition (n = 9; lateral mechanical instability, osteochondral defect, intra-articular bodies and osteoarthritis). Ultrasound examination included the antero-lateral gutter for abnormal synovial tissue (synovitic lesion), lateral ligament integrity, tibiotalar joint and osseous spurs of the distal tibia and talus. Ultrasound findings were correlated with subsequent arthroscopic appearance. Results Ultrasound examination detected a synovitic mass in the antero-lateral gutter in all 8 footballers with clinical ALI (100%) and in 2 patients with a control diagnosis (22%). Arthroscopic correlation of antero-lateral synovitis and fibrosis was present in all 10 cases (100%). The synovitic lesion was seen at ultrasound as a nodular soft tissue mass of mixed echogenicity within the antero-lateral gutter, which extruded anteriorly with manual compression of the distal fibula against the tibia. Increased blood supply was detected using power Doppler imaging in only 1 patient. The synovitic lesion measured >10 mm in its maximum dimension in 7 footballers with clinical ALI and <10 mm in the control group. Additional ultrasound findings in patients with abnormal antero-lateral synovial tissue included an anterior talofibular ligament injury in all patients (n = 10), a tibiotalar joint effusion (n = 6) and osseous spurs (n = 4). Antero-lateral synovitic tissue was accurately identified at ultrasound in the absence of an effusion (n = 4). No synovitic lesion was detected at ultrasound or arthroscopy in the remaining 7 patients with a control diagnosis. Conclusion Ultrasound is accurate in detecting synovitic lesions within the antero-lateral gutter, demonstrating associated ligamentous injuries and in differentiating soft tissue from osseous impingement. Synovitic lesions in two control patients suggest that abnormal antero-lateral soft tissue does not necessarily imply the presence of symptomatic ALI. Synovitic lesions in excess of 10 mm were associated with symptoms. Ultrasound will not demonstrate osteocartilaginous lesions or stress fractures and may overlook some loose bodies. Ultrasound findings together with clinical correlation can be used to direct arthroscopic examination and surgical debridement.  相似文献   
84.
The epidural blood patch is considered effective in treating postdural puncture headache. We have developed a postdural puncture model in rats for quantitative evaluation of the magnitude and duration of changes in cerebrospinal fluid (CSF) pressure in the cisterna magna in response to the administration of epidural blood or other moieties. This model was used to compare the efficacy of various methods of epidural injection for restoring and maintaining CSF pressure for up to 240 min. After lumbar dural puncture, CSF pressure declined 3.6 +/- 0.2 mm Hg. Epidural saline (100 microL) injected at the puncture site initially increased pressure by 7.2 +/- 0.7 mm Hg, but it rapidly (7.8 +/- 0.6 min) returned to postdural puncture baseline. A similar initial increase of CSF pressure was observed with equal volumes of all other epidural injectates, but the duration of pressure increase varied greatly. Hetastarch and dextran 40 produced results similar to saline. Only whole blood or fibrin glue consistently increased CSF pressure for the entire 240-min observation period. Whole blood mixed with anticoagulant or injected 20-mm cephalad to the puncture site did not sustain pressure. After laminectomy, direct application of blood or adhesive to the dural defect caused no pressure increase. Continuous infusion of saline after bolus could maintain pressure increase for 180 min, but within 60 min of stopping infusion, pressure returned to baseline. These results confirm the efficacy of the epidural administration of blood or fibrin glue to correct CSF hypotension after dural puncture and also provide insight into the mechanisms of intracranial pressure modulation. Sealing the dural defect does not effectively correct CSF pressure unless an epidural tamponade effect is also maintained. IMPLICATIONS: A rat model was developed to evaluate different drugs that may be injected epidurally to treat postdural puncture headache. Epidural injection of blood or fibrin glue was the most effective method of maintaining increased cerebrospinal fluid pressure after dural puncture. Sealing the dural defect does not effectively correct cerebrospinal fluid pressure unless an epidural tamponade effect is maintained.  相似文献   
85.
A novel nonthiazolidinedione dual peroxisome proliferator- activated receptor (PPAR)-alpha/gamma agonist, LY465608, was designed to address the major metabolic disturbances of type 2 diabetes. LY465608 altered PPAR-responsive genes in liver and fat of db/db mice and dose-dependently lowered plasma glucose in hyperglycemic male Zucker diabetic fatty (ZDF) rats, with an ED(50) for glucose normalization of 3.8 mg small middle dot kg(-1) small middle dot day(-1). Metabolic improvements were associated with enhanced insulin sensitivity, as demonstrated in female obese Zucker (fa/fa) rats using both oral glucose tolerance tests and hyperinsulinemic-euglycemic clamps. Further characterization of LY465608 revealed metabolic changes distinct from a selective PPAR-gamma agonist, which were presumably due to the concomitant PPAR-alpha agonism, lower respiratory quotient, and less fat accumulation, despite a similar impact on glycemia in male ZDF rats. In addition to these alterations in diabetic and insulin-resistant animals, LY465608 dose-dependently elevated HDL cholesterol and lowered plasma triglycerides in human apolipoprotein A-I transgenic mice, demonstrating that this compound significantly improves primary cardiovascular risk factors. Overall, these studies demonstrate that LY465608 beneficially impacts multiple facets of type 2 diabetes and associated cardiovascular risk, including those facets involved in the development of micro- and macrovascular complications, which are the major sources for morbidity and mortality in these patients.  相似文献   
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A dramatic shortage of total hip arthroplasty (THA) and total knee arthroplasty (TKA) surgeons has been projected because fewer residents enter arthroplasty fellowships, and the demand for THAs/TKAs is rising. The purposes of this study were to ascertain the future supply of THA/TKA surgeons, to identify the criteria residents use to choose their fellowship specialty, and to assess resident perceptions of an arthroplasty career. Four hundred ninety-eight post-graduate year 3 and above residents completed the online survey. Residents most highly prioritize intellectual factors and role models/mentors in determining their fellowship specialty. In the face of a looming patient access-to-care crisis, the data from this study support a policy of highlighting the intellectual challenges and satisfaction of THA/TKA as a career and encouraging mentorship early in a resident's training.  相似文献   
88.
Cle aring the cervical spine in a multiply injured trauma patient is a dilemma because clinical examination for ligamentous instability cannot be performed, and the standard cervical spine series can miss isolated ligamentous injury. Static flexion/extension views are unsafe, as the obtunded patient has no protective reflexes and cannot complain of pain during the exam. This results in a need for prolonged spinal immobilization and its attendant complications. Dynamic fluoroscopy may be useful in the detection of otherwise occult injuries.We performed a prospective study of a cervical spine clearance algorithm incorporating dynamic fluoroscopy with flexion/extension views. Inpatient records over a 3-year period were reviewed. Patient demographic data, results of cervical spine films and fluoroscopic exams, interventions based on positive results, and missed injuries were recorded.One hundred ten patients with normal spine plain films underwent dynamic fluoroscopy with flexion and extension views of the cervical spine. The average Glasgow Coma Score was 9.2 and the average revised Trauma Score was 9.5. Nine patients had evidence of cervical instability on exam. Six of these were deemed stable by the orthopedic or neurosurgical spine consultants, and these patients had their hard collars removed. One patient with positive findings had cervical immobilization with hard collar continued, a second had halo placement, and a third underwent spinal fusion for atlanto-occipital disassociation. No patients undergoing dynamic fluoroscopy were subsequently found to have missed cervical spine injury.With our protocol, 3 patients had significant cervical instability that would have been missed without dynamic fluoroscopy. Given the significant medical and legal ramifications of missed cervical spine injury and the benefits of early removal of cervical collars, more widespread use of dynamic fluoroscopy of the cervical spine is warranted.  相似文献   
89.
Is repair preferable to replacement for ischemic mitral regurgitation?   总被引:12,自引:0,他引:12  
OBJECTIVE: This study was undertaken to compare mitral valve repair and replacement as treatments for ischemic mitral regurgitation. METHODS: From 1985 through 1997, a total of 482 patients with ischemic mitral regurgitation underwent either valve repair (n = 397) or valve replacement (n = 85). Patients more likely (P < or =.01) to undergo repair had functional mitral regurgitation or coronary revascularization with an internal thoracic artery graft; those more likely to receive valve replacement were in higher New York Heart Association functional classes or underwent emergency operations. These factors were used for multivariable propensity matching. Risk factors for early and late death were identified by multivariable, multiphase hazard function analysis. RESULTS: Within the propensity-matched better-risk group, survivals after valve replacement were 81%, 56%, and 36% at 30 days, 1 year, and 5 years, but survivals after repair were 94%, 82%, and 58% at these intervals (P =.08). In contrast, within the poor-risk group, survivals after repair and replacement were similar (P =.4). Risk factors (P < or =.01) included older age, higher functional class, greater wall motion abnormality, and renal dysfunction. Approximately 70% of patients were predicted to benefit from repair; the benefit lessened or was negated if an internal thoracic artery graft was not used, if a lateral wall motion abnormality was present, or if the mitral regurgitation jet pattern was complex. Freedom from repair failure at 5 years was 91%. CONCLUSION: Late survival is poor after surgery for ischemic mitral regurgitation. Most patients with ischemic mitral regurgitation benefit from mitral valve repair. In the most complex, high-risk settings, survivals after repair and replacement are similar.  相似文献   
90.
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