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41.

Summary

Using combined dual-energy X-ray absorptiometry (DXA) and quantitative computed tomography, we demonstrate that men matched with women for femoral neck (FN) areal bone mineral density (aBMD) have lower volumetric BMD (vBMD), higher bone cross-sectional area, and relatively similar values for finite element (FE)-derived bone strength.

Introduction

aBMD by DXA is widely used to identify patients at risk for osteoporotic fractures. aBMD is influenced by bone size (i.e., matched for vBMD, larger bones have higher aBMD), and increasing evidence indicates that absolute aBMD predicts a similar risk of fracture in men and women. Thus, we sought to define the relationships between FN aBMD (assessed by DXA) and vBMD, bone size, and FE-derived femoral strength obtained from quantitative computed tomography scans in men versus women.

Methods

We studied men and women aged 40 to 90?years and not on osteoporosis medications.

Results

In 114 men and 114 women matched for FN aBMD, FN total cross-sectional area was 38% higher (P?P?Conclusions In this cohort of young and old men and women from Rochester, MN, USA who are matched by FN aBMD, because of the offsetting effects of bone size and vBMD, femoral strength and the load-to-strength ratio tended to be relatively similar across the sexes.  相似文献   
42.
Purpose: To compare the clinical outcomes in patients with chronic renal insufficiency (CRI) and renal artery stenosis (RAS) following renal artery (RA) stent placement with and without embolic protection device (EPD) usage. Materials and Methods: Eighteen patients who had RA stent placement with EPD were matched to control patients (RA stent only). Blood pressure, number of hypertensive medications, and estimated glomerular filtration rate (eGFR) at 3 months before the procedure and after 12 months were determined. An increase of ≥ 20% in eGFR at 12 months from baseline was defined as "improvement," decrease of ≥20% as "deterioration," and an eGFR change between those values as "stabilization" at 12 months. Results: At 12 months, stage 4 patients treated with EPD had significantly higher eGFR than controls (P = .01). There was no statistical difference in blood pressure outcomes between the 2 groups. Conclusions: Patients with stage 4 CRI did significantly better with EPD than those treated without it.  相似文献   
43.

Background

Previous studies have demonstrated that diabetic patients undergoing exercise stress single-photon emission-computed tomography (SPECT) myocardial perfusion imaging (MPI) have significantly lower cardiac events when compared to the diabetic patients undergoing pharmacologic stress SPECT MPI across all perfusion categories. However, there are limited data on the level of exercise achieved during exercise SPECT MPI among diabetic patients and its impact on cardiovascular outcomes.

Methods

We retrospectively analyzed 14,849 consecutive patients (3,654 diabetics and 11,195 non-diabetics) undergoing exercise stress, combined exercise and pharmacologic stress, and pharmacologic stress SPECT MPI from 1996 to 2005 at a single tertiary care center. Diabetic and non-diabetic patients were categorized into 3 groups based on the metabolic equivalents (METs) achieved: ≥5 METs, <5 METs, and pharmacologic stress groups. All studies were interpreted using the 17-segment ASNC model. The presence, extent, severity of perfusion defects were calculated using the summed stress score (SSS), and patients were classified into normal (SSS < 4), mildly abnormal (SSS 4-8), and moderate-severely abnormal (SSS > 8) categories. Annualized event rates (AER) for the composite end point of non-fatal myocardial infarction and cardiac death were calculated over a mean follow-up period of 2.4 ± 1.4 years with a maximum of 6 years.

Results

In moderate-severe perfusion abnormality (SSS > 8) category, diabetic patients who were able to achieve ≥5 METs had significantly lower AER compared to diabetic patients who were unable to achieve ≥5 METs (3% vs 5.5%, P = .04), and non-diabetic patients unable to achieve ≥5 METs (3% vs 4.8%, P < .001). Diabetic patients who achieved a high workload of ≥10 METs had a very low AER of 0.9%. Diabetic patients, who attempted exercise but were unable to achieve ≥5 METs, still had significantly lower AER than diabetics undergoing pharmacologic stress MPI across all perfusion categories [1.5% vs 3.2%, P = .006 (SSS < 4); 2.5% vs 4.9%, P = .032 (SSS 4-8); 5.5% vs 10.3%, P = .003 (SSS > 8)]. After adjustment for cardiovascular risk factors, the percentage decrease in cardiac event rate for every 1-MET increment in exercise capacity was 10% in the overall cohort, 12% in diabetic group, and 8% in non-diabetic group.

Conclusions

Despite significant perfusion defects, diabetic patients who achieve ≥5 METs during stress SPECT MPI have significantly reduced risk for future cardiac events. Diabetic patients who achieve ≥10 METs have a very low annualized event rate. These findings support that exercise capacity obtained during SPECT MPI is a surrogate for outcomes among diabetic patients undergoing nuclear stress testing.  相似文献   
44.
Renal transplant recipients are prone to a variety of infections due a persistent immunodepleted state. Incidence of tuberculosis in this population is much higher compared with the general population. While pulmonary tuberculosis still remains the commonest form in this population, renal allograft tuberculosis is very rare. We report two cases of isolated allograft tuberculosis and one case of allograft tuberculosis with coexistent pleuro-pulmonary and bone marrow involvement. All three cases had presented with pyrexia of unknown origin, wherein despite extensive investigations the cause was not found. In two cases the diagnosis was confirmed on histology. Two cases responded to non-rifampicin-based modified antitubercular treatment and one to conventional four-drug Rifampicin-based regimen. Graft function improved in two cases while in one case the graft was lost. Tuberculosis involving the renal allograft is a potential cause for graft dysfunction/loss and requires a high index of suspicion for diagnosis. Timely detection and early institution of therapy can help save the renal allograft.  相似文献   
45.
A 33 years old female patient presented with posttraumatic pain in the right foot for which radiographs of the right foot was advised. No fracture was detected on radiographs and patient was managed conservatively on medications and posterior splint immobilization. We found coincidentally a short fourth metatarsal and an accessory navicular bone in the right foot radiographs. After 3 weeks of immobilization, she underwent mobilization of the right foot, weight bearing and intensive physiotherapy for 6 weeks. After two months of injury she was still complaining of pain on the plantar aspect of right foot which was diagnosed as metatarsalgia and operated on by excision of the neuroma present in the 3rd web space of the right foot. After surgery she was completely relieved of pain and could do activities well related to the right foot.  相似文献   
46.
Purpose: Fractures of the humeral shaft are common and account for 3%e5% of all orthopedic injuries. This study aims to estimate the incidence of radial nerve palsy and its outcome when the anterior approach is employed and to analyze the predictive factors. Methods: The study was performed in the department of orthopaedics unit of a tertiary care trauma referral center. Patients who underwent surgery for acute fractures and nonunions of humerus shaft through an anterior approach from January 2007 to December 2012 were included. We retrospectively analyzed medical records, including radiographs and discharge summaries, demographic data, surgical procedures prior to our index surgery, AO fracture type and level of fracture or nonunion, experience of the operating surgeon, time of the day when surgery was performed, and radial nerve palsy with its recovery condition. The level of humerus shaft fracture or nonunion was divided into upper third, middle third and lower third. Irrespective of prior surgeries done elsewhere, the first surgery done in our institute through an anterior approach was considered as the index surgery and subsequent surgical exposures were considered as secondary procedures. Results: Of 85 patients included, 19 had preoperative radial nerve palsy. Eleven (16%) patients developed radial nerve palsy after our index procedure. Surgeons who have two or less than two years of surgical experience were 9.2 times more likely to induce radial nerve palsy (p=0.002). Patients who had surgery between 8 p.m. and 8 a.m. were about 8 times more likely to have palsy (p=0.004). The rest risk factor is AO type A fractures, whose incidence of radial nerve palsy was 1.3 times as compared with type B fractures (p=0.338). For all the 11 patients, one was lost to follow-up and the others recovered within 6 months. Conclusion: Contrary to our expectations, secondary procedures and prior multiple surgeries with failed implants and poor soft tissue were not predictive factors of postoperative deficit. From our study, we also conclude that radial nerve recovery can be reasonably expected in all patients with a postoperative palsy following the anterolateral approach.  相似文献   
47.
Development of a contralateral epidural haematoma during or immediately after cranial surgery is a well-described entity. However, in a case of acute subdural haematoma where the brain is usually tense, postoperative development of contralateral extradural haematoma is uncommon. We report two cases of contralateral extradural haematoma after decompressive surgery for acute subdural haematoma. We recommend routine postoperative CT immediately after cranial surgery for head trauma. This would help in timely detection and treatment of such a complication.  相似文献   
48.
OBJECTIVES: To determine the effects of combined radiation and targeted, intra-arterial (IA) cisplatin infusions (RADPLAT) in patients with advanced squamous cell carcinoma (SCC) of the tonsil. STUDY DESIGN AND SETTING: Prospective study of treatment outcomes and toxicity of patients enrolled on the RADPLAT protocol, with specific analysis of patients with advanced SCC of the tonsil. RESULTS: Thirty patients with advanced tonsil carcinoma (17 T(4), 12 T(3), 1 T(2)) were enrolled, and 24 of 30 patients completed at least 3 IA cisplatin infusions and a minimum of 63 Gy or radiation therapy (minimum therapy). Two-year estimated overall and disease-specific survival was 42% and 50%, respectively, for all 30 patients (intent-to-treat group) and 49% and 58%, respectively, for the minimum therapy subgroup. The 2-year estimated local and regional disease control was 87% and 90%, respectively, for the intent-to-treat group, and 100% and 90% for the minimum therapy subgroup. Functional organ preservation was achieved in 92% of patients. CONCLUSIONS: Locoregional disease control achieved with this regimen appears to be significantly improved over that described in the literature for similarly staged tonsil cancer. Survival, on the other hand, remains comparable.  相似文献   
49.
Background. Asymmetric glenohumeral range-of-motion (ROM) between the throwing and non-throwing arms of overhead athletes has been well described in the literature. Thresholds of internal rotation (IR) loss have been associated with throwing arm injury in baseball players. Acute changes in shoulder ROM following an individual pitching appearance remain poorly understood. Objectives: To determine the acute change of external rotation (ER), IR, and total arc-of-motion (TAM) in minor league starting pitchers immediately following an in-season starting pitching appearance. Methods. Nine minor league starting pitchers participated in the study with data collected for 22 individual starts. IR, ER and TAM were measured in the throwing shoulder and non-throwing shoulder at three time points for each appearance: before, immediately following, and at 24 hours following the pitching appearance. Results. In the throwing arm, IR significantly decreased (49.4 vs 46.0, p = 0.037) immediately after pitching, and ER significantly increased immediately following an appearance (150.7 vs 153.6, p = 0.030) and at 24 hours (150.7 vs 154.0, p = 0.028). No difference was detected in throwing arm TAM and IR at 24 hours, or TAM immediately following an appearance. Conclusions. Minor league pitchers demonstrate the dynamic glenohumeral ROM changes after starting appearances of increased ER and diminished IR with maintenance of TAM. At 24 hours, the observed loss of IR had resolved, whereas the gains in ER remained present. Our study supports the need to further assess the acute changes of glenohumeral ROM in pitchers, and the association of acute glenohumeral ROM change with the development of pathologic ROM profiles and injury.  相似文献   
50.
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