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991.

Background

Foot injuries represent a small but important proportion of injuries to professional rugby union players. There are no detailed epidemiological studies regarding these injuries. The aim of this study was to describe the epidemiology of foot injuries sustained by a cohort of professional rugby union players and identify areas that may be targeted for injury prevention in the future.

Methods

Medical personnel prospectively recorded injuries in professional Premiership rugby union players in England over four seasons. Injuries to the foot were identified and the time away from training and playing was reported.

Results

A total of 147 foot injuries were sustained resulting in 3542 days of absence in total. Acute events accounted for 73% of all foot injuries, with chronic, mostly overuse conditions, accounting for 25% (undiagnosed 2%). Chronic conditions led to proportionately more time away from training and playing (p = <0.001). Specifically, stress fractures in the foot accounted for 8% of the total foot injuries but 22% of the absence. Navicular stress fractures had the longest recovery time with the mean return to training and match play of 188 days.

Conclusion

In collision sports such as rugby, some injuries may be inevitable but clinicians should always be seeking ways to minimise their occurrence and impact. This study revealed a high proportion of morbidity associated with chronic and overuse foot injuries in these professional athletes. With greater attention paid to risk factors, some of these injuries, and importantly, recurrent injuries may be avoided.  相似文献   
992.
993.

Purpose

Many cases have been reported of hemodynamic and airway collapse induced by general anesthesia in patients with an anterior mediastinal mass. We examined the literature for predictors of perioperative risk, guidelines for preoperative investigations, and strategies for management of the patient with a mediastinal mass.

Principal findings

In patients with an anterior mediastinal mass, symptoms may range from none to severe and may include orthopnea, stridor, cyanosis, jugular vein distension, or superior vena cava syndrome. In limited case series, incidences of serious complications up to 20% were noted, but these are primarily pediatric studies with unclear relevance to adults. There is a paucity of evidence providing guidance on quantifying risk and planning the safe conduct of anesthesia. In the largest adult case series to date, intraoperative complications were associated only with the preoperative presence of a pericardial effusion. Postoperative complications were predicted by severe symptoms at presentation, tracheal compression of > 50%, and a mixed obstructive-restrictive picture on pulmonary function testing. Low-risk patients tolerate conventional general anesthesia with neuromuscular blockade and positive pressure ventilation. Those at intermediate or high risk are best managed with the maintenance of spontaneous ventilation, at least initially. Cardiopulmonary bypass remains the option of last resort.

Conclusions

It appears prudent to avoid general anesthesia when possible for patients at the highest risk. When general anesthesia is required, a comprehensive plan must be formulated preoperatively with the surgical team. Cardiopulmonary bypass requires time for implementation, so it should be considered early and appropriate preparations should be made prior to the initiation of anesthesia.  相似文献   
994.
We evaluated the average 7-year survivorship and clinical results of a newer primary posterior stabilized total knee arthroplasty (TKA). The modifications in this design included a deeper patellar sulcus aimed at reducing contact stresses, improving patellar tracking, and achieving greater maximum flexion. A consecutive group of 137 patients (171 knees) who underwent TKAs using the Optetrak PS knee prosthesis between October 1997 and March 2004 were followed for an average of 6.8?years (range 4.0-11.5?years). Preoperative range of motion (ROM) and Knee Society scores were obtained and compared to that of the patients' most recent follow-up. Manipulation under anesthesia (MUA) and revision of the implant for any reason were considered endpoints for Kaplan-Meier survival analysis of all knees. Twenty-one knees (12.3%) underwent MUA. Three knees (1.8%) underwent revision, resulting in a 97.2% survival at a mean 10?years follow-up. Pain scores and ROM significantly improved after surgery (from preoperative average of 5.3 and 105° respectively to 44.6 and 120° postoperatively). These findings suggest that this posterior stabilized knee design is both a safe and effective option for patients undergoing primary TKA.  相似文献   
995.

Background

The clinical trials mechanism of standardized treatment and follow-up for cancer patients with similar stages and patterns of disease is the most powerful approach available for evaluating the efficacy of novel therapies, and clinical trial participation should protect against delivery of care variations associated with racial/ethnic identity and/or socioeconomic status. Unfortunately, disparities in clinical trial accrual persist, with African Americans (AA) and Hispanic/Latino Americans (HA) underrepresented in most studies.

Study Design

We evaluated the accrual patterns for 10 clinical trials conducted by the American College of Surgeons Oncology Group (ACOSOG) 1999–2009, and analyzed results by race/ethnicity as well as by study design.

Results

Eight of 10 protocols were successful in recruiting AA and/or HA participants; three of four randomized trials were successful. Features that were present among all of the successfully recruiting protocols were: (1) studies designed to recruit patients with regional or advanced-stage disease (2 of 2 protocols); and (2) studies that involved some investigational systemic therapy (3 of 3 protocols).

Discussion

AA and HA cancer patients can be successfully accrued onto randomized clinical trials, but study design affects recruitment patterns. Increased socioeconomic disadvantages observed within minority-ethnicity communities results in barriers to screening and more advanced cancer stage distribution. Improving cancer early detection is critical in the effort to eliminate outcome disparities but existing differences in disease burden results in diminished eligibility for early-stage cancer clinical trials among minority-ethnicity patients.  相似文献   
996.

Purpose

Breast-conserving therapy (BCT) is an accepted method of treating early breast cancer. We hypothesized that routine excision of additional cavity shave margins (CSM) at time of initial partial mastectomy reduces the need for additional surgery.

Methods

A single-institution retrospective review was performed of women, 18 years or older, with a new diagnosis of breast cancer who underwent partial mastectomy between 1 January 2004 and 1 October 2009. Five hundred thirty-three charts were reviewed. Of those, 69 patients underwent CSM at time of initial operation. These 69 patients were matched with patients who had undergone partial mastectomy without CSM by tumor size, presence of extensive intraductal component, and primary histology.

Results

The two groups were well matched for age, nuclear grade, associated lymphovascular invasion (LVI), receptor status, and multifocality. We found that 31.9% (44/138) required return to the operating room (OR) for re-excision of margins. Rate of return to the OR was 21.7% (15/69) in the CSM group and 42.0% (29/69) in the matched group (p = 0.011). Multivariate analysis found factors significantly associated with need for additional operation included lack of CSM (odds ratio 9.2, 95% CI 2.8–30.5, p = 0.0003), larger extent of intraductal component (odds ratio 7.0, 95% CI 1.8–27.0, p = 0.005), and lack of directed re-excision (odds ratio 6.4, 95% CI 1.7–25.1, p = 0.007).

Conclusions

CSM at time of initial partial mastectomy decreases rate of re-excision by as much as ninefold. CSM should be considered at time of initial operation to reduce the need for subsequent reoperation.  相似文献   
997.
998.
OBJECTIVE: To evaluate speech performance and subjective outcomes for older individuals who have hearing impairment and use digital hearing aids. The outcomes between young and old elderly users were compared. STUDY DESIGN: Prospective. SUBJECTS AND METHODS: Fifty-nine patients with hearing loss fitted with digital hearing aids were included. They were divided into two groups. Group A consisted of 32 subjects aged 65 to 80 years, whereas group B had 27 subjects older than 80 years. Speech performance and subjective outcomes were measured 4 months after fitting of hearing aids. Hearing Handicap Inventory for the Elderly-Screening Version (HHIE-S), Client Oriented Scale of Improvement (COSI), satisfaction, and usage questionnaires were used as subjective assessments. RESULTS: Improvements in speech performance were not significantly different between these two groups. There were no statistical differences in terms of HHIE-S score reduction, satisfaction rate, daily usage time, and COSI scores between both groups. CONCLUSION: Age by itself is not a limiting factor for older patients with hearing impairment to benefit from digital hearing aids.  相似文献   
999.
Hip resurfacing has been experiencing a revival over the last 5-10 years. Early failure rates are higher than for conventional primary hip arthroplasty. Fractures of the femoral neck or head, cup loosening and persistent pain are the most frequently observed reasons for early revision. In this international retrospective uncontrolled study, 256 revision specimens (219 resurfacing heads, 37 cups) were analysed radiologically, tribologically, morphologically and histologically in order to investigate the failure mechanism. Of the head revisions, 70% were due to neck (median: 67 days after implantation) and head fractures (161 days), 9% were due to cup loosening (350 days) and 21% due to other reasons (602 days). Implants with rim loading (22% of all retrievals, cup inclination 58.0+/-10.9 degrees ) exhibited a head wear rate of 7.1+/-5.2 mm3/year. Non-rim loaded implants exhibited a head wear rate of 0.24+/-0.53 mm3/year (cup inclination 49.0+/-4.0 degrees ). The failure rate was highest during the first 16 weeks after surgery and for the first ten operations performed by a surgeon. Revisions based on problems on the femoral side such as notching and high implantation forces occurred earlier than revisions based on problems on the acetabular side such as cup loosening and high wear due to suboptimal cup position.  相似文献   
1000.
The number and status of lymph nodes examined is crucial for tumor staging. Impact of preoperative chemoradiotherapy on lymph nodes status and survival is still controversial in rectal carcinoma. The aim of this study was (i) to define the impact of preoperative chemoradiotherapy on the number of both retrieved and positive lymph nodes in rectal cancer specimen, (ii) to evaluate the influence of the number of lymph nodes retrieved on survival in patients treated by preoperative chemoradiotherapy. From 1994 to 2004, 495 patients underwent rectal excision for cancer, of which 332 received long course preoperative radiotherapy. Surgery and pathologic assessment were standardized. Multivariate analysis evaluated the influence of clinical and pathologic variables on the number of both retrieved and positive lymph nodes. Kaplan-Meier method and log-rank test assessed the relation between survival and the number of lymph nodes retrieved in patients treated by preoperative chemoradiotherapy. Compared with surgery alone, preoperative chemoradiotherapy decreased both the mean number of lymph nodes retrieved (17 vs. 13; P<0.001) and the mean number of positive lymph nodes (2.3 vs. 1.2; P=0.001). Multivariate analysis confirmed the independent impact of preoperative chemoradiotherapy on retrieved and positive lymph nodes. In patients treated by preoperative chemoradiotherapy, the 5-year overall (71%) and disease-free (60%) survival was not associated with the number of lymph nodes retrieved. Although long course preoperative chemoradiotherapy decreases by 24%, the mean number of lymph nodes retrieved and by 48% the mean number of positive lymph nodes, survival was not influenced by the number of lymph nodes retrieved in irradiated rectal specimen.  相似文献   
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