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991.
Splinting and nerve and tendon gliding exercises are commonly used to treat carpal tunnel syndrome (CTS). It has been postulated that both modalities reduce intraneural edema. To test this hypothesis, 20 patients with mild to moderate CTS were randomly allocated to either night splinting or a home program of nerve and tendon gliding exercises. Magnetic resonance images of the wrist were taken at baseline, immediately after 10 min of splinting or exercise, and following 1 week of intervention. Primary outcome measures were signal intensity of the median nerve at the wrist as a measure of intraneural edema and palmar bowing of the carpal ligament. Secondary outcome measures were changes in symptom severity and function. Following 1 week of intervention, but not immediately after 10 min, signal intensity of the median nerve was reduced by ≈ 11% at the radioulnar level for both interventions (p = 0.03). This was accompanied by a mild improvement in symptoms and function (p < 0.004). A similar reduction in signal intensity is not observed in patients who only receive advice to remain active. No changes in signal intensity were identified further distally (p > 0.28). Ligament bowing remained unchanged (p > 0.08). Intraneural edema reduction is a likely therapeutic mechanism of splinting and exercise.  相似文献   
992.
Moroder P  Resch H  Tauber M 《Arthroscopy》2012,28(1):138-144
Anterior impression fractures of the humeral head (reverse Hill-Sachs lesions) are typical concomitant bony injuries of posterior shoulder dislocations. When more than 20% of the humeral articulating surface is affected, surgical treatment is required, typically necessitating open surgery. Recently, cases of successful arthroscopic treatment of small reverse Hill-Sachs lesions involving less than 30% of the articulating surface have been reported. This article presents a case of a large reverse Hill-Sachs lesion affecting over 40% of the articulating surface that was treated arthroscopically by retrograde elevation, bone allografting, and cannulated screw insertion. The postoperative radiographic images showed a successful reduction of the impacted articulating surface of the humeral head. However, at 6 months' follow-up, the patient presented with pain and symptoms of a frozen shoulder. Cross-sectional imaging showed necrosis, partial absorption, and loss of reduction of the formerly elevated segment requiring humeral head replacement. This case report shows that even though the arthroscopic retrograde elevation of large reverse Hill-Sachs lesions is technically achievable, the outcome can be unsatisfactory because of the limitations in biologic healing response associated with large lesions of the humeral articulating surface.  相似文献   
993.

Background

The use of non-cultured autologous cells to promote wound healing and in reconstructive procedures is increasing. One common method for preparing these cells is the use of the ReCell® device. However, despite its current clinical use, no characterisation of the cell suspension produced using a ReCell® device has been published.

Objective

To characterise the ReCell suspension that is applied to wounds for cell type, viability, yield, stability and proliferative potential.

Methods

The ReCell® device was used to harvest cells from a 2 cm2 piece of split-thickness skin isolated using a dermatome. The resulting cell suspension was analysed for cell yield, cell type, viability over time, proliferative potential and reproducibility.

Results

Average viable cell yield was 1.7 × 106/cm2 of tissue, with 75.5% of the total cell isolate viable. Total viable cell number was not significantly reduced after 4 h storage at 22 °C or 4 °C, and was stable for 24 h at 4 °C. Proliferative potential was assessed using a colony forming assay, with 0.3% of viable cells isolated forming keratinocyte colonies. Predominantly the suspension contained keratinocytes (64.3 ± 28.8%) and fibroblasts (30.3 ± 14.0%), with a small population of melanocytes also identified (3.5 ± 0.5%). Finally, the supernatant contained low total protein (0.92 mg/ml) and the supernatant had no significant effects on cell viability or growth when applied ex vivo.

Conclusions

These results suggest the ReCell® device provides a method for the preparation of a cell suspension with high viability and proliferative potential, containing viable melanocytes and no apparent toxic cell debris. Further work on the sustained viability of these cells in vivo, and in particular after application to the wound, will be important to better understand the potential of the ReCell® device in the clinic.  相似文献   
994.

Introduction

Osteoporosis poses a significant public health problem for ageing Australians. However, approximately 25?% of Australian adults aged 20?C49?years have osteopenia, a precursor condition to osteoporosis. Despite this, little is known about bone density testing in this age group.

Methods

Reasons for referral to dual energy X-ray absorptiometry (DXA) were examined in 2,264 patients aged 20?C49?years, referred in 2001?C2010 to the Geelong Bone Densitometry Service, Geelong Hospital, Victoria. Referral reasons were determined from clinical indication codes derived from patient records. Age, sex and bone mineral density (BMD) T scores were ascertained for each patient.

Results

The most common reason for referral for women reflected glucocorticoid use, and for men reflected fracture. Compared to women, men were more likely to have been referred because of minimal trauma fracture or low BMD (41.7 versus 27.1?%, p?<?0.001). No further differences were identified between the sexes, with similar numbers of referral observed for secondary osteoporosis, and monitoring of drug therapy. At the spine, and for all indications, men had a significantly greater BMD deficit compared to women (all p????0.002). After age adjustment, men who were tested due to fracture or glucocorticoid reasons had significantly greater BMD at the total hip (p????0.03). No further associations were seen after age adjustment between referral reason and BMD.

Conclusions

Our study presents the first data examining reasons for referral to DXA among Australians aged 20?C49?years. Understanding health service utilisation regarding bone health in young adults is fundamental to understanding future risk, informing effective public health messages and raising awareness of osteoporosis.  相似文献   
995.
ML Prasarn  G Zych  G Gaski  D Baria  D Kaimrajh  T Milne  LL Latta 《Orthopedics》2012,35(7):e1028-e1032
To the authors' knowledge, no published studies have examined the use of locking plates on injuries of the anterior pelvic ring. The purpose of this study was to determine whether locked plates provide enhanced stability in the treatment of pubic symphyseal disruptions. Completely unstable pelvic injuries were simulated in pelvic Sawbones (model 1301; Pacific Research Laboratories, Vashon, Washington) and 2 different fixation constructs used for anterior fixation (4-hole, 3.5-mm pubic symphysis plate with all locked or all unlocked screws). Adjunctive sacroiliac screw fixation with a single 7.3-mm screw placed into S1 was used in all specimens. Specimens were analyzed for motion at the pubic symphysis and sacroiliac joints using a Material Testing System (MTS Systems Corporation, Eden Prairie, Minnesota). Each specimen was subjected to compressive loading in a single-limb stance. Side loading was also examined. The main outcome measurement was motion at the pubic symphysis and sacroiliac joints and overall construct stiffness. No significant difference existed in overall construct stiffness between the 2 methods of pubic symphysis fixation. The motions at the pubic symphysis or injured sacroiliac joints were not significantly different. In addition, motion at the pubic symphysis joint with lateral load was not improved with a locking construct.No significant difference existed between 4-hole locked or unlocked constructs used for fixation of the pubic symphysis. No apparent advantage of locking screws exists for disruptions of the pubic symphysis, and recent reports have questioned the possibility of catastrophic failure.  相似文献   
996.
BackgroundManagement of patients with severe concomitant carotid and coronary disease remains controversial. We report our experience of combined carotid endarterectomy (CEA) and coronary artery bypass surgery (CABG) over a fifteen year period using strict patient selection criteria.MethodsFrom 1st January 1995 to December 31st 2009 165 patients underwent combined CABG/CEA procedures at the Mater Hospital. Mean age was 68.2 years (range 43–88) and 127 (77%) were male. Fifty-three (32%) had symptomatic carotid disease. Indications for combined procedures were the presence of symptomatic >70% or asymptomatic >80% internal carotid artery stenosis in a patient requiring urgent CABG because of either unstable angina, recent MI, severe triple vessel disease or severe Left Anterior Descending or Left Main Stem stenosis.ResultsThirty-day stroke and death rate was 3%. All neurological events were in the hemisphere contralateral to the carotid surgery and symptoms had completely resolved prior to discharge from hospital. One patient required evacuation of a cervical haematoma and there were two transient XII nerve palsies.ConclusionCombined CEA/CABG can be performed safely with acceptable morbidity and mortality in patients selected in accordance with strict criteria in a centre with a large experience of both cardiac and carotid surgery.  相似文献   
997.
Study Type – Prognosis (case series) Level of Evidence 4 What's known on the subject? and What does the study add? Only 30–35% of patients with positive surgical margins after radical prostatectomy develop recurrent disease. Adjuvant radiotherapy reduces the rate of biochemical relapse or metastasis and improves overall survival after radical prostatectomy. Various pathological factors, such as location and extent of positive margins, have been proposed as possible prognostic factors in men with margin‐positive prostate cancer, however, the recent International Society of Urological Pathology consensus meeting in Boston noted that there is limited data on the significance of Gleason grade of the carcinoma at a positive margin. The present study shows that the presence of high grade prostate cancer, i.e. Gleason pattern 4 or 5, at a positive surgical margin is an independent predictor of biochemical recurrence after radical prostatectomy. Moreover, patients with lower grade carcinoma at the margin have a similar prognosis to men with negative margins. Hence, assessment of Gleason grade at the site of positive margin may aid optimal selection of patients for adjuvant radiotherapy.

OBJECTIVE

  • ? To establish predictors of biochemical recurrence by analysing the pathological characteristics of positive surgical margins (PSMs), including Gleason grade of the carcinoma at the involved margin.

PATIENTS AND METHODS

  • ? Clinicopathological and outcome data on 940 patients who underwent radical prostatectomy (RP) between 1997 and 2003 were collected.
  • ? Of these, 285 (30.3%) patients with PSMs were identified for pathological review, including assessment of location of margin, linear extent, number of PSMs, plane of margin and Gleason grade (3 vs 4 or 5) at the margin.

RESULTS

  • ? At a median follow‐up of 82 months, the biochemical recurrence rate of the PSM cohort was 29%.
  • ? On univariate analysis, the presence of Gleason grade 4 or 5 at the margin (34.4% of cases) was significantly associated with biochemical recurrence (hazard ratio [HR] 2.80, 95% confidence interval [CI]= 1.82–4.32, P < 0.001) compared with the presence of Gleason grade 3.
  • ? Linear extent of margin involvement was also associated with recurrence (P= 0.009).
  • ? Single vs multiple margin involvement, location, and plane of the involved margin were not significant predictors of recurrence.
  • ? On multivariate analysis, Gleason grade 4 or 5 at the margin remained an independent predictor of recurrence (HR 2.14, 95% CI = 1.29–4.03, P= 0.003).

CONCLUSION

  • ? The Gleason grade at the site of a PSM identifies patients at increased risk of biochemical recurrence and should aid stratification of patients for adjuvant radiation therapy.
  相似文献   
998.
Study Type – Prognostic (RCT) Level of Evidence 1b What's known on the subject? and What does the study add? Previous studies used the decrease in PSA after 6 months of dutasteride treatment as a new ‘baseline’ PSA value from which subsequent rises may serve as a warning for prostate cancer; however, PSA tends to continue to decrease as dutasteride treatment continues. By comparing positive biopsy rates in the REDUCE study using any rise from nadir in the dutasteride arm and standard PSA decision criteria (NCCN) in the placebo arm, we demonstrated that the ability to detect prostate cancer and high grade prostate cancer is maintained with dutasteride treatment.

OBJECTIVES

? To determine if dutasteride‐treated men can be monitored safely and adequately for prostate cancer based on data from the Reduction by Dutasteride in Prostate Cancer Events (REDUCE) study. ? To analyse whether the use of treatment‐specific criteria for repeat biopsy maintains the usefulness of prostate‐specific antigen (PSA) level for detecting high grade cancers.

PATIENTS AND METHODS

? The REDUCE study was a randomized, double‐blind, placebo‐controlled investigation of whether dutasteride (0.5 mg/day) reduced the risk of biopsy‐detectable prostate cancer in men with a previous negative biopsy. ? The usefulness of PSA was evaluated using biopsy thresholds defined by National Comprehensive Cancer Network guidelines in the placebo group and any rise in PSA from nadir (the lowest PSA level achieved while in the study) in the dutasteride group. ? The number of cancers detected on biopsy in the absence of increased/suspicious PSA level as well as sensitivity, specificity, positive predictive value and negative predictive value for high grade prostate cancer detection were analysed by treatment group. ? Prostate cancer pathological characteristics were compared between men who did and did not meet biopsy thresholds.

RESULTS

? Of 8231 men randomized, 3305 (dutasteride) and 3424 (placebo) underwent at least one prostate biopsy during the study and were included in the analysis. ? If only men meeting biopsy thresholds underwent biopsy, 25% (47/191) of Gleason 7 and 24% (7/29) of Gleason 8–10 cancers would have been missed in the dutasteride group, and 37% (78/209) of Gleason 7 and 22% (4/18) Gleason 8–10 cancers would have been missed in the placebo group. ? In both groups, the incidence of Gleason 7 and Gleason 8–10 cancers generally increased with greater rises in PSA. ? Sensitivity of PSA kinetics was higher and specificity was lower for the detection of Gleason 7–10 cancers in men treated with dutasteride vs placebo. ? Men with Gleason 7 and Gleason 8–10 cancer meeting biopsy thresholds had greater numbers of positive cores, percent core involvement, and biopsy cancer volume vs men not meeting thresholds.

CONCLUSION

? Using treatment‐specific biopsy thresholds, the present study shows that the ability of PSA kinetics to detect high grade prostate cancer is maintained with dutasteride compared with placebo in men with a previous negative biopsy. ? The sensitivity of PSA kinetics with dutasteride was similar to (Gleason 8–10) or higher than (Gleason 7–10) the placebo group; however, biopsy decisions based on a single increased PSA measurement from nadir in the dutasteride group resulted in a lower specificity compared with using a comparable biopsy threshold in the placebo group, indicating the importance of confirmation of PSA measurements.  相似文献   
999.

Introduction

Although gallstone pancreatitis is initiated by the presence of stones in the common bile duct, the benefit associated with routine intraoperative cholangiography at the time of cholecystectomy in these patients is unclear. The purpose of this study, using population-based data, was to determine the impact of cholangiography on clinical outcomes after cholecystectomy for gallstone pancreatitis.

Methods

All patients who were admitted to hospital from January 1, 1997 to December 31, 2001 in Nova Scotia, Canada with pancreatitis who underwent cholecystectomy during the same admission were identified. The rates of recurrent pancreatitis and biliary complications after surgery were compared between patients who underwent cholecystectomy with intraoperative cholangiography ± common bile duct exploration and those who underwent cholecystectomy alone, using three linked administrative databases.

Results

Three hundred thirty-two patients were identified, 119 had cholangiography at the time of cholecystectomy and 213 did not. After a median follow-up of after 3.8?years, there was no difference in the rate of recurrent pancreatitis or biliary complications between those who had cholangiography ± common bile duct exploration at the time of surgery and those who did not; 13.4 versus 10.8?%, respectively (p?=?0.55).

Conclusions

These data suggest that intraoperative cholangiography does not improve outcomes after cholecystectomy for gallstone pancreatitis.  相似文献   
1000.

Background

Intermittent, reversible intraabdominal vagal blockade (VBLOC? Therapy) demonstrated clinically important weight loss in feasibility trials. EMPOWER, a randomized, double-blind, prospective, controlled trial was conducted in USA and Australia.

Methods

Five hundred three subjects were enrolled at 15 centers. After informed consent, 294 subjects were implanted with the vagal blocking system and randomized to the treated (n?=?192) or control (n?=?102) group. Main outcome measures were percent excess weight loss (percent EWL) at 12?months and serious adverse events. Subjects controlled duration of therapy using an external power source; therapy involved a programmed algorithm of electrical energy delivered to the subdiaphragmatic vagal nerves to inhibit afferent/efferent vagal transmission. Devices in both groups performed regular, low-energy safety checks. Data are mean ± SEM.

Results

Study subjects consisted of 90?% females, body mass index of 41?±?1?kg/m2, and age of 46?±?1?years. Device-related complications occurred in 3?% of subjects. There was no mortality. 12-month percent EWL was 17?±?2?% for the treated and 16?±?2?% for the control group. Weight loss was related linearly to hours of device use; treated and controls with ??12?h/day use achieved 30?±?4 and 22?±?8?% EWL, respectively.

Conclusions

VBLOC? therapy to treat morbid obesity was safe, but weight loss was not greater in treated compared to controls; clinically important weight loss, however, was related to hours of device use. Post-study analysis suggested that the system electrical safety checks (low charge delivered via the system for electrical impedance, safety, and diagnostic checks) may have contributed to weight loss in the control group.  相似文献   
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