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61.

Background

Periacetabular osteotomy (PAO) is the treatment of choice for younger patients with developmental hip dysplasia. The procedure aims to normalize the joint configuration, reduce the peak-pressure, and delay the development of osteoarthritis. The procedure is technically demanding and no previous study has validated the use of computer navigation with a minimally invasive transsartorial approach.

Methods

Computer-assisted PAO was performed on ten patients. Patients underwent pre- and postoperative computed tomography (CT) scanning with a standardized protocol. Preoperative preparation consisted of outlining the lunate surface and segmenting the pelvis and femur from CT data. The Biomechanical Guidance System was used intra-operatively to automatically calculate diagnostic angles and peak-pressure measurements. Manual diagnostic angle measurements were performed based on pre- and postoperative CT. Differences in angle measurements were investigated with summary statistics, intraclass correlation coefficient, and Bland–Altman plots. The percentage postoperative change in peak-pressure was calculated.

Results

Intra-operative reported angle measurements show a good agreement with manual angle measurements with intraclass correlation coefficient between 0.94 and 0.98. Computer navigation reported angle measurements were significantly higher for the posterior sector angle (\(1.65^{\circ }\), \(p=0.001\)) and the acetabular anteversion angle (\(1.24^{\circ }\), \(p=0.004\)). No significant difference was found for the center-edge (\(p=0.056\)), acetabular index (\(p=0.212\)), and anterior sector angle (\(p=0.452\)). Peak-pressure after PAO decreased by a mean of 13% and was significantly different (\(p=0.008\)).

Conclusions

We found that computer navigation can reliably be used with a minimally invasive transsartorial approach PAO. Angle measurements generally agree with manual measurements and peak-pressure was shown to decrease postoperatively. With further development, the system will become a valuable tool in the operating room for both experienced and less experienced surgeons performing PAO. Further studies with a larger cohort and follow-up will allow us to investigate the association with peak-pressure and postoperative outcome and pave the way to clinical introduction.
  相似文献   
62.

Background

Preoperative progressive resistance training (PRT) is controversial in patients scheduled for total knee arthroplasty (TKA), because of the concern that it may exacerbate knee joint pain and effusion.

Objective

To examine whether preoperative PRT initiated 5 weeks prior to TKA would exacerbate pain and knee effusion, and would allow a progressively increased training load throughout the training period that would subsequently increase muscle strength.

Design

Secondary analyses from a randomized controlled trial (NCT01647243).

Setting

University Hospital and a Regional Hospital.

Patients

A total of 30 patients who were scheduled for TKA due to osteoarthritis and assigned as the intervention group.

Methods

Patients underwent unilateral PRT (3 sessions per week). Exercise loading was 12 repetitions maximum (RM) with progression toward 8 RM. The training program consisted of 6 exercises performed unilaterally.

Main outcome measures

Before and after each training session, knee joint pain was rated on an 11-point scale, effusion was assessed by measuring the knee joint circumference, and training load was recorded. The first and last training sessions were initiated by 1 RM testing of unilateral leg press, unilateral knee extension, and unilateral knee flexion.

Results

The median pain change score from before to after each training session was 0 at all training sessions. The average increase in knee joint effusion across the 12 training sessions was a mean 0.16 cm ± 0.23 cm. No consistent increase in knee joint effusion after training sessions during the training period was found (P = .21). Training load generally increased, and maximal muscle strength improved as follows: unilateral leg press: 18% ± 30% (P = .03); unilateral knee extension: 81% ± 156% (P < .001); and unilateral knee flexion: 53% ± 57% (P < .001).

Conclusion

PRT of the affected leg initiated shortly before TKA does not exacerbate knee joint pain and effusion, despite a substantial progression in loading and increased muscle strength. Concerns for side effects such as pain and effusion after PRT seem unfounded.

Level of Evidence

I  相似文献   
63.
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65.
Since Ebola virus disease was identified in West Africa on March 23, 2014, the Centers for Disease Control and Prevention (CDC) has undertaken the most intensive response in the agency’s history; >3,000 staff have been involved, including >1,200 deployed to West Africa for >50,000 person workdays. Efforts have included supporting incident management systems in affected countries; mobilizing partners; and strengthening laboratory, epidemiology, contact investigation, health care infection control, communication, and border screening in West Africa, Nigeria, Mali, Senegal, and the United States. All efforts were undertaken as part of national and global response activities with many partner organizations. CDC was able to support community, national, and international health and public health staff to prevent an even worse event. The Ebola virus disease epidemic highlights the need to strengthen national and international systems to detect, respond to, and prevent the spread of future health threats.  相似文献   
66.
67.
[11C]Carbon monoxide (11CO) is a versatile building block for the synthesis of Positron Emission Tomography (PET) radioligands. However, the difficulty of trapping 11CO in a small solvent volume has limited its utility. We here report an evaluation of a simple, fully automated high‐pressure synthesizer prototype for the use in 11C‐carbonylation reactions. [11C]Carbon monoxide was easily prepared by online reduction of [11C]carbon dioxide using either Mo(s) or Zn(s) as the reducing agent. The conversion yield of 11CO was >99% when zinc was used as the reducing agent, and the corresponding value for Mo was approximately 71%. When the Zn or Mo column was constantly kept under inert atmosphere, no significant decrease in reducing properties was observed for more than 100 11CO productions. However, in our hands, Mo reductant was much easier to service. A total of nine functional groups were successfully radiolabeled using the 11CO synthesizer prototype. All measured radiochemical yields exceeded 37%, and the 11CO trapping efficiency was generally above 90%, except for the Suzuki coupling where the trapping efficiency was 80%. This high‐pressure synthesizer using [11C]carbon monoxide as the labeling precursor is easy to operate allowing for 11C‐carbonylation reactions to be performed in a high yield and in a routinely fashion.  相似文献   
68.
Our objective was to assess whether administration of 25-OH-vitamin D to children with asthma treated with inhaled dry-powder budesonide 400 microg daily affects short-term growth or markers of bone turnover. We utilized a randomized, double-blind, two-period crossover trial with run-in and washout periods of 2 weeks and treatment periods of 4 weeks duration. The setting was an Outpatient clinic in a secondary referral center. Subjects included 14 boys and 3 girls with a mean age of 11.7 (range, 6.1-14.4) years. Interventions included 15 microg (600 IU) 25-OH-vitamin D (cholecalciferol) in one tablet ABCDin(R) once daily in the morning. Primary outcome measures were: lower leg growth rate, serum osteocalcin, and serum markers of type I collagen turnover, i.e., the amino terminal propeptide of type I procollagen (PINP), the carboxy terminal propeptide of type I procollagen (PICP) (formation markers), and the carboxy terminal pyridinoline cross-linked telopeptide of type I collagen (ICTP) (degradation markers). Secondary outcome measures were parameters of asthma control and serum 25-OH-vitamin D. Lower leg growth rate was 0.22 mm/week during vitamin D and 0.25 mm/week during placebo treatment (NS). Osteocalcin was 59.9 and 57.8 microg/l during vitamin D and placebo treatment, respectively, PINP 574 and 565 microg/l, PICP 381 and 382 microg/l, and ICTP 11.5 and 11.1 microg/l, respectively (NS). Serum 25-OH-vitamin D was 76.3 nmol/l and 48.2 nmol/l, respectively (P < 0.001). There were no statistically significant differences in measures of pulmonary function. In conclusion, administration of 25-OH-vitamin D does not affect short-term growth or markers of bone turnover in children with asthma treated with inhaled dry-powder budesonide 400 microg daily.  相似文献   
69.
OBJECTIVE: To examine whether blood pressure over 24 h differed between postmenopausal women receiving and not receiving hormone replacement therapy. METHODS: One group of hormone replacement postmenopausal women (n = 32) and one group of non-hormone replacement (n = 32) postmenopausal women underwent non-invasive 24-h ambulatory blood pressure monitoring. They were randomly selected among the 2000 firstly screened women in an ongoing project in Lund, Sweden. The study was designed to detect a difference of 5 mmHg in diastolic blood pressure over 24 h with a power of 80% and 5% significance (two-tailed test). RESULTS: The hormone replacement women had a mean (SD) office blood pressure of 128/76 (12/8) mmHg and the non-hormone replacement 126/78 (16/8) mmHg. Mean ambulatory blood pressure over 24 h, day and night, in the hormone replacement group was 121/72 (11/7), 126/76 (12/8), 111/64 (11/7) mmHg. The corresponding values in the non-hormone replacement group were 118/72 (12/7), 124/77 (12/7), and 107/64 (13/7) (p > 0.40 for diastolic blood pressure and p > 0.20 for systolic blood pressure). Mean heart rate over 24 h was 71 (7) and 73 (8) beats/min in the hormone and non-hormone replacement groups, respectively. CONCLUSION: There was no difference in blood pressure or heart rate between the hormone replacement and non-hormone replacement postmenopausal women, either over 24 h or during the day or night. Hormone replacement in postmenopausal women seems not to have an influence on blood pressure, but of course we are aware that this is a cross-sectional study, which has its limitations.  相似文献   
70.
Summary For evaluation of its prognostic value, the level of serum -2-microglobulin was determined in early serum samples from 88 patients with persistent generalized lymphadenopathy in a prospective longitudinal study. Patients with serum -2-microglobulin >2.6 mg/l were found to have a significantly higher risk of developing AIDS earlier when compared to patients with a lower level (p<0.001).
Erhöhte -2-Mikroglobulin-Serumspiegel — prognostischer Marker für den Übergang in AIDS bei Patienten mit persistierender, generalisierter Lymphadenopathie
Zusammenfassung In einer prospektiven longitudinalen Studie wurden in frühen Serumproben von 88 Patienten mit persistierender generalisierter Lymphadenopathie Messungen des -2-Mikroglobulin-Spiegels vorgenommen, um dessen Wert als prognostischer Faktor zu bestimmen. Das Risiko für den Übergang in AIDS erwies sich bei Patienten mit -2-Mikroglobulin-Spiegeln von >2,6 mg/l als signifikant höher als bei Patienten mit niedrigeren Spiegeln (p<0,001).
  相似文献   
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