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101.
BACKGROUND AND PURPOSE: Intravertebral clefts have long been considered as pathognomonic for avascular necrosis and as a rare cause of compression fracture. We have observed unsuspected clefts opacifying frequently during vertebroplasty. Our purpose in this study was to determine the incidence of these clefts in symptomatic osteoporotic compression fractures, assess the sensitivity of MR imaging and conventional radiography in the detection of these clefts, and determine whether there is any prognostic significance of these clefts in patients treated with vertebroplasty. METHODS: Retrospective chart reviews were conducted of 135 vertebroplasty procedures performed during a 2-year period. MR images and conventional radiographs were reviewed for the presence of clefts defined as fluid-filled cavities on MR images or gas-filled cavities on conventional radiographs. Digital radiographs obtained at the time of the procedure were inspected for the presence of opacified clefts. Imaging findings were correlated with subjective pain scores documented before the procedure and at 1 week, 1 month, 6 months, and 12 months after vertebroplasty. RESULTS: Two hundred thirty-six osteoporotic compression fractures were treated with polymethylmethacrylate in 125 patients. Thirty-one and eight-tenths percent of the fractures were noted to contain clefts at the time of vertebroplasty. Fluid-filled clefts were detected on preoperative MR images in only 52.8% of the fractures with opacified clefts at vertebroplasty. Gas-filled clefts were evident on preoperative conventional radiographs in only 11.4% of the fractures with opacified clefts at vertebroplasty. No significant difference was noted in numerical pain scores between the two populations at baseline or 1 week or 1 month after the procedure. Pain scores at 6 and 12 months after vertebroplasty showed a trend toward greater pain relief in patients with clefts, although the difference was not statistically significant. A sustained, statistically significant decrease in pain scores after treatment (P <.01) was noted in both groups. CONCLUSION: Intravertebral clefts are much more common than previously described and probably represent fracture nonunions. Imaging is not sensitive in detecting these clefts before vertebroplasty. We advocate complete filling of the cleft with cement during vertebroplasty to maximize stabilization of the fracture fragments. There is a trend toward greater pain relief being achieved 6 and 12 months after the procedure in patients with clefts that are opacified at the time of vertebroplasty.  相似文献   
102.
OBJECTIVE: We evaluated the incidence and organ distribution of arterial extravasation identified using contrast-enhanced helical CT in patients who had sustained abdominal visceral injuries and pelvic fractures after blunt trauma. SUBJECTS AND METHODS: Five hundred sixty-five consecutive patients from four level I trauma centers who had CT scans showing abdominal visceral injuries or pelvic fractures were included in this series. The presence or absence of arterial extravasation, as well as the anatomic sites of arterial extravasation, was noted. We obtained clinical follow-up data, including surgical or angiographic findings. RESULTS: In our series, 104 (18.4%) of 565 patients had arterial extravasation. Of the 104 patients, 81 (77.9%) underwent surgery, embolization, or both. The combined rate of surgery or embolization in patients with arterial extravasation was statistically higher than expected at all four institutions (p <0.001). The spleen was the most common organ injured, occurring in 277 (49.0%) of 565 patients, and arterial extravasation occurred in 49 (17.7%) of 277 patients with splenic injury. Several other visceral injuries were associated with arterial extravasation, including hepatic, renal, adrenal, and mesenteric injuries. CONCLUSION: Based on the limited reports of arterial extravasation in the nonhelical CT literature, the percentage (18%) of clinically stable patients in our study with CT scans showing arterial extravasation was higher than anticipated. This finding likely reflects the improved diagnostic capability of helical CT. Although the spleen and liver were the organs most commonly associated with arterial extravasation, radiologists should be aware that arterial extravasation may be associated with several other visceral injuries.  相似文献   
103.
BACKGROUND: Solid organ transplant recipients, particularly simultaneous pancreas kidney recipients, are at high fracture risk. We tested whether quantitative ultrasonography (QUS) of the heel predicts bone mineral density (BMD) by dual energy X-ray absorptiometry (DXA) in solid organ transplant recipients. METHODS: Thirty-eight transplant recipients (22 Female/16 Male) were studied. Spine and hip BMD was measured with a Hologic DXA scanner. 'Stiffness' of the heel was measured with a Lunar Ultrasound densitometer and compared with BMD by DXA. Contributing factors to bone loss were also assessed. RESULTS: Mean age was 43.1 +/- 1.3 yr. Simultaneous pancreas-kidney, kidney, and pancreas alone transplant recipients were assessed. Mean time post-transplantation was 3.0 +/- 0.6 yr. Mean DXA spine T-score was -1.15 +/- 0.22 (mean +/- SEM) and hip T-score was -1.22 +/- 0.20. There was no difference in mean T-score between women and men at the hip or spine. Mean right heel stiffness T-score was -0.97 +/- 0.25. There was no correlation between QUS and DXA at either the hip or spine in women or men. QUS had a false negative rate for identifying osteopenia or osteoporosis of 17% compared with DXA. The false positive rate for identifying osteopenia was 61%. CONCLUSIONS: The QUS is an unacceptable tool for identifying those at risk for bone loss after kidney or pancreas transplantation.  相似文献   
104.
BACKGROUND: Somatosensory evoked potentials (SSEPs) have long been recognized as an excellent tool for detecting neural and vascular compromise during vascular, neurosurgical and orthopedic procedures. SSEPs have the ability to localize, central versus peripheral, the area of compromise. Many surgeons use only lower-limb SSEP monitoring when performing lumbar spinal surgery. The upper extremities are usually not monitored during such procedures, and monitoring oxygen saturation does not detect neural compromise. PURPOSE: To report that the expanded use of SSEP monitoring during surgery can be beneficial in detecting peripheral ischemia or neural compromise resulting from positioning. STUDY DESIGN: Three case reviews of orthopedic spine surgeries where SSEP monitoring provided early warnings of vascular and neural compression. METHODS: The cases review three different lumbar procedures in which evidence of peripheral ischemia and nerve compression were detected by SSEP monitoring. RESULTS: By the use of upper- and lower-extremity monitoring during lumbar procedures, early detection of ischemia and nerve compression were noted intraoperatively. These changes prompted examination of the patient and repositioning to correct the ischemia or compression. The repositioning in these cases corrected the problem, and no lasting effects were found. CONCLUSIONS: Including SSEP monitoring of the bilateral upper extremities should be considered during lumbar spinal procedures. Such monitoring can be offered for a slightly increased expense and only minimal time delay to place the additional required electrodes by the technician. As a direct result of the early warning of the SSEP monitoring, we were able to avoid potential ischemic injuries and improve patient outcomes.  相似文献   
105.
Objectives. The management of intractable urinary incontinence in the patient with cloacal or bladder exstrophy/epispadias, failed bladder neck plasty, or failed augmentation cystoplasty remains a surgical challenge. The myofascial wrap, a modification of the rectus fascial wrap, was developed to treat intractable urinary incontinence due to sphincteric incompetence in these problematic cases. A full-thickness, vascularized pedicle of anterior rectus sheath, rectus abdominis muscle, and posterior rector sheath is incorporated into a bladder neck wrap to provide support, mucosal coaptation, and active muscular tone.Methods. Eight patients (5 females and 3 males) with total urinary incontinence due to sphincteric incompetence underwent the myofascial wrap. Urinary tract pathology included cloacal exstrophy (2), female epispadias (2), classic bladder exstrophy (1), male epispadias (1), myelomeningocele (1), and a pelvic tumor (1). The procedure is performed by harvesting a full-thickness strip of pedicled rectus muscle along with the anterior and posterior fascial sheaths. The strip is passed underneath and then over the bladder neck in a near 360° wrap. The free end of the wrap is anchored into the pubic bone in an ipsilateral subperiosteal pouch.Results. Six of the 8 patients are completely continent, and 2 patients void spontaneously without the need for catheterization.Conclusions. The myofascial wrap provides support, mucosal coaptation, and muscular tone to an incompetent sphincter and bladder neck. Favorable results in a very difficult population of pediatric patients warrant its continued use.  相似文献   
106.
Antiosteoporotic medications are often used to concurrently treat a patient’s fragility fractures and underlying osteoporosis. This review evaluates the existing literature from animal and clinical models to determine these drugs’ effects on fracture healing. The data suggest that these medications may enhance bone healing, yet more thorough prospective studies are warranted. Pharmacologic agents that influence bone remodeling are an essential component of osteoporosis management. Because many patients are first diagnosed with osteoporosis when presenting with a fragility fracture, it is critical to understand how osteoporotic medications influence fracture healing. Vitamin D and its analogs are essential for the mineralization of the callus and may also play a role in callus formation and remodeling that enhances biomechanical strength. In animal models, antiresorptive medications, including bisphosphonates, denosumab, calcitonin, estrogen, and raloxifene, do not impede endochondral fracture healing but may delay repair due to impaired remodeling. Although bisphosphonates and denosumab delay callus remodeling, they increase callus volume and result in unaltered biomechanical properties. Calcitonin increases cartilage formation and callus maturation, resulting in improved biomechanical properties. Parathyroid hormone, an anabolic agent, has demonstrated promise in animal models, resulting in accelerated healing with increased callus volume and density, more rapid remodeling to mature bone, and improved biomechanical properties. Clinical data with parathyroid hormone have demonstrated enhanced healing in distal radius and pelvic fractures as well as postoperatively following spine surgery. Strontium ranelate, which may have both antiresorptive and anabolic properties, affects fracture healing differently in normal and osteoporotic bone. While there is no effect in normal bone, in osteoporotic bone, strontium ranelate increases callus bone formation, maturity, and mineralization; forms greater and denser trabeculae; and improves biomechanical properties. Further clinical studies with these medications are needed to fully understand their effects on fracture healing in order to simultaneously treat fragility fractures and underlying osteoporosis.  相似文献   
107.
Aim:   Coronary artery calcification (CAC) has been associated with higher mortality in chronic renal disease. The purpose of this study was to assess coronary artery calcium score (CaCs) in haemodialysis patients and to correlate calcium scores with clinical parameters and mortality.
Methods:   A cross-sectional study was conducted in 59 haemodialysis patients. CaCs was assessed by multidetector-row computed tomography and stratified as: CaCs of less than 10 Agatston units (U), no calcification; CaCs of 10–400 U, mild-to-moderate; and CaCs of more than 400 U, severe calcification. The effects of age, haemodialysis duration and biochemical and inflammatory markers on CaCs logarithm were evaluated by multiple linear regression analysis. Cox regression analysis was used to measure the impact of CaCs of more than 400 on 2-year mortality.
Results:   Coronary calcifications were detected in 64.5% of patients, and the median of CaCs was 31.7 U (0–589.7) with a range of 0–5790.0 U. Twenty-one (35.5%) patients had mild-to-moderate and 17 (29%) severe CaCs. Patients with severe CaCs were older and showed a higher prevalence of ischaemic heart disease and a higher body mass index ( P  = 0.04). A trend towards higher C-reactive protein levels was found in patients with severe CaCs. Advanced age was the only variable that influenced CaCs logarithm independently. The effect of severe CaCs on 2-year mortality did not persist after adjustment for other covariates.
Conclusion:   Coronary calcification was highly prevalent in these uraemic patients on chronic haemodialysis. A correlation was evidenced between CaCs and advanced age, but severity of the CAC score did not have an impact on 2-year mortality of this cohort.  相似文献   
108.
BACKGROUND: Tubulointerstitial damage plays an important role in chronic kidney disease (CKD) with proteinuria. Urinary kidney injury molecule 1 (KIM-1) reflects tubular KIM-1 and is considered a sensitive biomarker for early tubular damage. We hypothesized that a decrease in proteinuria by using therapeutic interventions is associated with decreased urinary KIM-1 levels. STUDY DESIGN: Post hoc analysis of a randomized, double-blind, placebo-controlled, crossover trial. SETTING & PARTICIPANTS: 34 proteinuric patients without diabetes from our outpatient renal clinic. INTERVENTION: Stepwise 6-week interventions of losartan, sodium restriction (low-sodium [LS] diet), their combination, losartan plus hydrochlorothiazide (HCT), and the latter plus an LS diet. OUTCOMES & MEASUREMENTS: Urinary excretion of KIM-1, total protein, and N-acetyl-beta-d-glucosaminidase (NAG) as a positive control for tubular injury. RESULTS: Mean baseline urine protein level was 3.8 +/- 0.4 (SE) g/d, and KIM-1 level was 1,706 +/- 498 ng/d (increased compared with healthy controls; 74 ng/d). KIM-1 level was decreased by using placebo/LS (1,201 +/- 388 ng/d; P = 0.04), losartan/high sodium (1,184 +/- 296 ng/d; P = 0.09), losartan/LS (921 +/- 176 ng/d; P = 0.008), losartan/high sodium plus HCT (862 +/- 151 ng/d; P = 0.008) and losartan/LS plus HCT (743 +/- 170 ng/d; P = 0.001). The decrease in urinary KIM-1 levels paralleled the decrease in proteinuria (R = 0.523; P < 0.001), but not blood pressure or creatinine clearance. 16 patients reached target proteinuria with protein less than 1 g/d, whereas KIM-1 levels normalized in only 2 patients. Urinary NAG level was increased at baseline and significantly decreased during the treatment periods of combined losartan plus HCT only. The decrease in urinary NAG levels was not closely related to proteinuria. LIMITATIONS: Post hoc analysis. CONCLUSIONS: Urinary KIM-1 level was increased in patients with nondiabetic CKD with proteinuria and decreased in parallel with proteinuria by using losartan, sodium restriction, their combination, losartan plus HCT, and the latter plus sodium restriction. These results are consistent with the hypothesis of amelioration of proteinuria-induced tubular damage. Long-term studies are warranted to evaluate whether targeting treatment on KIM-1 can improve outcomes in patients with CKD with proteinuria.  相似文献   
109.
Adults with β thalassemia major frequently have low BMD, fractures, and bone pain. The purpose of this study was to determine the prevalence of low BMD, fractures, and bone pain in all thalassemia syndromes in childhood, adolescence, and adulthood, associations of BMD with fractures and bone pain, and etiology of bone disease in thalassemia. Patients of all thalassemia syndromes in the Thalassemia Clinical Research Network, ≥6 yr of age, with no preexisting medical condition affecting bone mass or requiring steroids, participated. We measured spine and femur BMD and whole body BMC by DXA and assessed vertebral abnormalities by morphometric X‐ray absorptiometry (MXA). Medical history by interview and review of medical records, physical examinations, and blood and urine collections were performed. Three hundred sixty‐one subjects, 49% male, with a mean age of 23.2 yr (range, 6.1–75 yr), were studied. Spine and femur BMD Z‐scores < ?2 occurred in 46% and 25% of participants, respectively. Greater age, lower weight, hypogonadism, and increased bone turnover were strong independent predictors of low bone mass regardless of thalassemia syndrome. Peak bone mass was suboptimal. Thirty‐six percent of patients had a history of fractures, and 34% reported bone pain. BMD was negatively associated with fractures but not with bone pain. Nine percent of participants had uniformly decreased height of several vertebrae by MXA, which was associated with the use of iron chelator deferoxamine before 6 yr of age. In patients with thalassemia, low BMD and fractures occur frequently and independently of the particular syndrome. Peak bone mass is suboptimal. Low BMD is associated with hypogonadism, increased bone turnover, and an increased risk for fractures.  相似文献   
110.
This Classic article is a reprint of the original work by William Arbuthnot Lane, The Operative Treatment of Fractures. An accompanying biographical sketch on William Arbuthnot Lane, M.S., F.R.C.S., is available at DOI  10.1007/s11999-009-0861-3. The Classic Article is ©1909 by Wolters Kluwer Health-Lippincott Williams &; Wilkins and is reprinted with permission from Lane WA. The operative treatment of fractures. Ann Surg. 1909;50:1106.  相似文献   
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