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91.
A 70-year-old woman with a history of bilateral primary knee osteoarthritis presented with a left knee wound complication, a non-Hodgkins lymphoma, after bilateral total knee arthroplasties. After exploring several etiologies, the evidence in this unusual case suggests a coincidental preexisting lymphoma.
Mark S. EskanderEmail:
  相似文献   
92.
BACKGROUND: In children with complex multilevel left ventricular outflow tract obstruction (LVOTO), the Konno aortoventriculoplasty is used to enlarge the aortic root and increase the size of the aortic valve implanted. We present our experience with the evolution of this surgical approach from prosthetic valves to the Ross operation. METHODS: Between March 1982 and July 2000, 60 patients (36 males and 24 females) had 72 Konno aortoventriculoplasties (prosthetic valve and Konno group [57 patients; redo, 12] and Ross-Konno group [15 patients]). The patients' ages ranged from 5 days to 18 years (mean, 8.2 years). The underlying anatomic diagnoses were congenital aortic stenosis and LVOTO in 51 patients, coarctation of the aorta with bicuspid aortic valve in 13, severe aortic insufficiency associated with a ventricular septal defect in 8, interrupted aortic arch in 6, mitral stenosis in 6, atrioventricular septal defect in 5, and endocarditis in 3. There was no statistical difference in age or diagnosis between the two groups. The prosthetic valve group included 42 mechanical valves, 9 homografts, and 6 xenografts. RESULTS: Follow-up ranged from 10 months to 18.5 years (mean, 9.7 years) in the prosthetic valve and Konno group compared with 5 months to 3.7 years (mean, 2.1 years) in the Ross-Konno group (p < 0.05). There were 10 early deaths and four late deaths in the prosthetic valve and Konno group as compared with one early death and two late deaths in the Ross-Konno group (p = not significant). Reoperations for LVOTO and aortic valve replacement were significantly higher in the prosthetic valve and Konno group as opposed to the Ross-Konno group (16 vs 0, p < 0.05) mainly because of the biological valve and Konno subgroup. There were no statistical differences in reexploration for bleeding, pacemaker insertion, and reoperations for indications other than LVOTO and aortic valve replacement between the two groups. CONCLUSIONS: The Konno aortoventriculoplasty is a good surgical option for complex LVOTO. Patients with a prosthetic valve and Konno carry a high rate of reoperation. Early operative results with the Ross-Konno operation seem promising.  相似文献   
93.
Transplant patients are at the risk for posttransplant lymphoproliferative disease (PTLD), a virally-driven malignancy. Induction with the depleting antibody preparations Thymoglobulin and OKT3 is associated with PTLD suggesting that the T-cell depletion increases PTLD risk. We therefore studied 59 560 kidney recipients from the Organ Procurement and Transplantation Network/United Network for Organ Sharing (OPTN/UNOS) database for a relationship between induction agent use and PTLD. Two agents with comparable T-cell depletional effects, alemtuzumab and Thymoglobulin, were compared to nondepletional induction agents or no induction. The overall incidence of PTLD was 0.46% and differed significantly by induction strategy (p < 0.01): without induction (0.43%), basiliximab (0.38%), daclizumab (0.33%), Thymoglobulin (0.67%) and alemtuzumab (0.37%). Thymoglobulin was associated with significantly increased PTLD risk (p = 0.0025), but alemtuzumab (p = 0.74), basiliximab (p = 0.33) and daclizumab, which trended toward a protective effect (p = 0.06), were not. Alemtuzumab and Thymoglobulin treated patients did not differ in any established parameter affecting PTLD risk although alemtuzumab is known to have a more pronounced B-cell depleting effect. Interestingly, maintenance therapy with an mTOR inhibitor was strongly associated with PTLD (0.71%, p < 0.0001). Thus, depletional induction is not an independent risk factor for PTLD. Rather, maintenance drug selection or perhaps the balance between B- and T-cell depletion may be more relevant determinants of PTLD risk.  相似文献   
94.
We report the long-term survival of a prospective randomised consecutive series of 501 primary knee replacements using the press-fit condylar posterior cruciate ligament-retaining prosthesis. Patients received either cemented (219 patients, 277 implants) or cementless (177 patients, 224 implants) fixation. Altogether, 44 of 501 knees (8.8%) underwent revision surgery (24 cemented vs 20 cementless). For cemented knees the 15-year survival rate was 80.7% (95% confidence interval (CI) 71.5 to 87.4) and for cementless knees it was 75.3% (95% CI 63.5 to 84.3). There was no significant difference between the two groups (cemented vs cementless; hazard ratio (HR) 0.83, 95% CI 0.45 to 1.52, p = 0.55). When comparing the covariates there was no significant difference in the rates of survival between the side of operation (HR 0.58, p = 0.07), age (HR 0.97, p = 0.10) and diagnosis (HR 1.25 p = 0.72). However, there was a significant gender difference, with males having a higher failure rate with cemented fixation (HR 2.48, p = 0.004). Females had a similar failure rate in both groups. This single-surgeon series, with no loss to follow-up, provides reliable data of the revision rates of one of the most commonly-used total knee replacements. The survival of the press-fit condylar total knee replacement remained good at 15 years, irrespective of the method of fixation.  相似文献   
95.
STUDY DESIGN: Questionnaire study presented to practicing spine surgeons. OBJECTIVE: To evaluate surgeon preference and availability of selected electrophysiologic neuromonitoring for different spine surgeries. SUMMARY OF BACKGROUND DATA: Maximizing the safety of spinal procedures and limiting potential iatrogenic neurologic injury has made intraoperative neuromonitoring an attractive option. METHODS: We distributed a questionnaire to 180 orthopedic spine surgeons and neurosurgeons at a clinically oriented spine meeting asking surgeon preference and availability of various types of intraoperative neuromonitoring modalities for different types of surgical procedures. Demographic data were also gathered. RESULTS: Somatosensory evoked potentials (SSEPs) were the most available neuromonitoring modality, followed by electromyographies and motor-evoked potentials. In both anterior and posterior cervical surgery, SSEPs were the most preferred modality. MEPs were frequently preferred in myelopathic cervical cases. Almost 70% preferred some neuromonitoring for anterior thoracic/thoracolumbar cases and 55% for posterior thoracic/thoracolumbar cases. Surgeon satisfaction was related to the number of available neuromonitoring modalities. No significant differences were found between orthopedist and neurosurgeon preferences. Fellowship-trained surgeons were more likely to use neuromonitoring for specific indications. CONCLUSIONS: SSEPs remains the most widely available and preferred type of neuromonitoring for spine surgeons. The type of case and neurologic status of patient (eg, presence of myelopathy) affects these choices. Surgeons were more satisfied with greater neuromonitoring availability, and were more likely to use neuromonitoring if they had a fellowship background.  相似文献   
96.
OBJECTIVES: Endograft repair holds considerable promise in the treatment of traumatic disruption of the thoracic aorta because patients often have multiple coexisting injuries further complicating traditional open repair. In addition, patients are often young, with an aortic anatomy dissimilar to those with atherosclerotic aneurysms. As a result, techniques for endograft repair have to be refined accordingly. METHODS: The records of 20 consecutive cases of traumatic aortic disruption treated by endograft repair at a single institution were reviewed. RESULTS: Mean patient age was 40 years (range, 17 to 88 years), and 17 (85%) of 20 patients were men. All cases were completed. There were no procedure related deaths, but four (20%) patients died of their co-injuries. Only two (10%) of 20 required a graft >28 mm in diameter, and nine (45%) aortas were small enough to require use of 23-mm abdominal cuffs. Six (30%) of 20 cases required complete or partial coverage of the left subclavian artery. Placement of a proximal extension was required in one patient for a type I endoleak. A graft collapse occurred in one patient that required surgical removal and aortic repair. CONCLUSIONS: Endovascular repair of traumatic aortic disruption can be accomplished in most cases. Compared with atherosclerotic aneurysms, the proximal thoracic aorta tends to be smaller and the arch angle tighter in an aorta 19mm in diameter. This frequently necessitates the use of smaller devices and less stiff wires. Surgeons should be prepared to cover the left subclavian artery if needed, have a wide range of device sizes in stock to avoid over-sizing, and show restraint if the anatomy appears unsuitable.  相似文献   
97.
Urinary tract malformations, obstructive uropathy, and hypoplasia/dysplasia are extremely important in terms of pediatric health care costs, with end-stage renal failure in children estimated to cost >$15 billion annually in the United States alone. Even so, little is known regarding the mechanisms that control these processes. Identified was a unique mutant mouse model that develops in utero megabladder, resulting in variable hydroureteronephrosis and chronic renal failure secondary to obstructive uropathy. These animals, designated mgb for megabladder, possess a primary defect in bladder smooth muscle development that is apparent by embryonic day 15. The mgb mouse represents an excellent model for the study of normal and pathogenic bladder development, including the postnatal progression of chronic renal failure that results from the development of in utero obstructive uropathy.  相似文献   
98.
The present study was conducted to review the long-term results of femoral varus osteotomy with/without pelvic osteotomy of spastic cerebral palsy. We also evaluated the spastic hip score with following factors: migration index of Reimer's, Shenton's line, shape of the femoral head, shape of the roof of the acetabulum, and presence of windblown effect. Of the 31 children (61 hips) reviewed, 49 hips (80%) had satisfactory outcomes after 10 years of follow-up. Twelve hips showed unsatisfactory outcomes with recurrent dislocation or significant osteoarthritis. A low preoperative spastic hip score was more indicative of a better outcome.  相似文献   
99.
Thoracic aorta disease remains a challenging problem, and despite improvements, open repair techniques are still associated with significant morbidity and mortality. This is a retrospective review of 53 consecutive patients with thoracic aortic pathology who were treated with endovascular repair between September 1998 and December 2004 at a tertiary-care hospital. Endovascular stent graft placement was performed on 23 elective and 30 emergent patients (34 male patients, mean age 66 years, 21 to 85 years). Completion angiography revealed no endoleak in 47 (89%) patients, a type I endoleak in 4 patients, and a type II endoleak in 2 patients. Operative 30-day mortality for elective aneurysms (n = 22), emergent aneurysms (n = 10), dissection (n = 3), penetrating aortic ulcers (n = 7), and trauma (n = 11) was 0%, 40%, 0%, 29%, and 9%, respectively. In total, 46 (87%) patients survived 30 days, and 36 (78.3%) of the survivors were discharged home free of complications. Two patients (4%) experienced paraplegia. Median follow-up was 22 months (1 to 72 months). Intermediate-term results revealed 41 (89%) patients free of endoleak, stent migration, or aneurysmal expansion. Two (4%) patients required reintervention with an additional stent graft. There were 2 (4%) patients with late aortic-related deaths and four (9%) patients with non-aorticrelated late deaths. Endovascular stent graft placement for thoracic aorta disease can be performed successfully and safely with good perioperative and intermediate-term outcomes. Stent graft complication and reintervention rates are low, whereas intermediate survival rates are good. Long-term efficacy still needs to be evaluated.  相似文献   
100.
We have carried out a long-term survival analysis of a prospective, randomised trial comparing cemented with cementless fixation of press-fit condylar primary total knee replacements. A consecutive series of 501 replacements received either cemented (219 patients, 277 implants) or cementless (177 patients, 224 implants) fixation. The patients were contacted at a mean follow-up of 7.4 years (2.7 to 13.0) to establish the rate of survival of the implant. The ten-year survival was compared using life-table and Cox's proportional hazard analysis. No patient was lost to follow-up. The survival at ten years was 95.3% (95% CI 90.3 to 97.8) and 95.6% (95% CI 89.5 to 98.2) in the cemented and cementless groups, respectively. The hazard ratio for failure in cemented compared with cementless prostheses was 0.97 (95% CI 0.36 to 2.6). A comparison of the clinical outcome at ten years in 80 knees showed no difference between the two groups. The survival of the press-fit condylar total knee replacement at ten years is good irrespective of the method of fixation and brings into question the use of more expensive cementless implants.  相似文献   
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