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There are still no sufficient data regarding the use of deep brain stimulation (DBS) in Gilles de la Tourette syndrome (GTS) and no agreement on optimal target. To compare efficacy and safety of bilateral DBS of thalamus (centromedian-ventro-oral internus, CM-Voi) versus posteroventral lateral globus pallidus internus (pvl GPi)) versus sham stimulation, and baseline in severe medically refractory GTS. In this randomized double-blind sham stimulation-controlled trial (RCT), 10 patients (3 women, mean age = 29.4 ± 10.2 SD, range 18–47) underwent three blinded periods each lasting three months including (i) sham, (ii) pvl GPi (on-GPi), and (iii) thalamic stimulation (on-thal) followed by an open uncontrolled long-term follow-up (up to 9 years) with individually determined target and stimulation settings. Nine patients completed the RCT. At group level, on-GPi – but not on-thal – resulted in a significant tic reduction compared to baseline, but had no effect on premonitory urges and psychiatric comorbidities. Direct comparisons of targets resulted in inconsistent or negative (compared to sham) findings. During follow-up, we found no improvement of tics, comorbidities, and quality of life at group level, however, single patients benefitted continuously from thalamic DBS. At last follow-up 89.9 months (mean) after surgery, 50% of patients had discontinued DBS. Hardware infections occurred in 3/10 patients. Our data suggest that the initial effect of pvl GPi DBS is superior to thalamic (CM-Voi) DBS. While half of the patients discontinued treatment, single patients benefitted from thalamic DBS even after years. It is likely that outcome is influenced by various factors beyond the mere change in tic severity. • GPi DBS resulted in a significant tic reduction during the blinded study phase. • Beneficial effects on tics decreased after several years. • Seven years (mean) after surgery, single patients benefitted from thalamic DBS. • DBS was complicated by a high infection rate (30% of patients). • Results seem to be influenced by various factors including placebo effects. [ABSTRACT FROM AUTHOR]

Poor bone status is associated with increased complications following orthopedic surgery. Therefore, assessing site-specific skeletal status prior to or after orthopedic surgery to optimize outcomes is appealing. The trabecular bone score (TBS) approach, a surrogate for microarchitecture, was adapted to the Texture Research Investigational Platform (TRIP), which allows assessment of many skeletal sites imaged by various modalities. TRIP generates a bone texture score (TBS ORTHO), which could potentially guide surgical decision-making and offer insight into postsurgical fracture risk. As distal femur bone loss occurs following total knee arthroplasty (TKA), we hypothesized that TBS ORTHO after TKA would identify poorer texture in the operated femur compared to the nonoperated. We evaluated 30 subjects (15 M/15 F) with unilateral TKA 2–5 yr previously, mean age 67.9 yr and body mass index 30 kg/m2. Using a Lunar iDXA, lumbar spine and entire femur scans were obtained, the latter using the atypical femur fracture feature. Distal femur bone mineral density (BMD) and TBS ORTHO were obtained using manual regions of interest (ROI) at 15% and 25% of leg length from the intercondylar notch. TBS ORTHO was determined using distal femur DICOM images and TRIP v1.0 (Medimaps, France). Differences in operated vs nonoperated femur were evaluated by paired t test. As previously reported, operated leg BMD was approx 10% lower at 15% and 25% ROIs. Similarly, TBS ORTHO values in the operated leg were approx 5% lower (p < 0.05) at these same ROIs. Distal femur TBS ORTHO and BMD were largely unrelated. TBS ORTHO reproducibility at these ROIs was approx 3.5%. In conclusion, this pilot study documents the feasibility of reproducibly obtaining distal femur TBS ORTHO values. Lower values were observed in the surgical leg, consistent with the bone loss that follows TKA. Further work is indicated to refine TRIP use and evaluate whether such data provides guidance for surgical decision-making and improves periprosthetic fracture prediction. [ABSTRACT FROM AUTHOR]

Abstract Objective: High quality dual energy X-ray absorptiometry (DXA) acquisition, analysis, and reporting demands technical and interpretive excellence. We hypothesized that DXA errors are common and of such magnitude that incorrect clinical decisions might result. In this 2-phase study, we evaluated DXA technical and interpretation error rates in a clinical population and subsequently assessed if implementing an interpretation template reduced errors. Methods: In phase 1, DXA scans of 345 osteoporosis clinic referrals were reviewed by International Society for Clinical Densitometry-certified technologists (n = 3) and physicians (n = 3). Technologists applied International Society for Clinical Densitometry performance standards to assess technical quality. Physicians assessed reporting compliance with published guidance, relevance of technical errors and determined overall and major error prevalence. Major errors were defined as "provision of inaccurate information that could potentially lead to incorrect patient care decisions." In phase 2, a DXA reporting template was implemented at 2 clinical DXA sites after which the 3 physicians reviewed 200 images and reports as above. The error prevalence was compared with the 298 patients in phase 1 from these sites. Results: In phase 1, technical errors were identified in 90% of patients and affected interpretation in 13%. Interpretation errors were present in 80% of patients; 42% were major. The most common major errors were reporting incorrect information on bone mineral density change (70%) and incorrect diagnosis (22%). In phase 2, at these 2 clinical sites, major errors were present in 37% before and 17% after template implementation. Template usage reduced the odds of major error by 66% (odds ratio 0.34, 95% confidence interval 0.21, 0.53, and p < 0.0001). Conclusion: DXA technical and interpretation errors are extremely common and likely adversely affect patient care. Implementing a DXA reporting template reduces major errors and should become common practice. Additional interventions, such as requiring initial and ongoing training and/or certification for technologists and interpreters, are suggested. [ABSTRACT FROM AUTHOR]

Abstract Introduction: Total knee arthroplasty (TKA) is increasingly being performed. Distal femur periprosthetic fracture is a potentially catastrophic complication following TKA and existing data document substantial distal femur bone mineral density (BMD) loss following TKA. However, distal femur BMD is virtually never measured clinically as no consensus approach exists. This pilot study's purpose was to define regional BMD variation throughout the femur, suggest standard dual-energy X-ray absorptiometry (DXA) regions of interest (ROIs) and evaluate BMD reproducibility at these ROIs. Methods: Thirty volunteers 2–5 yr post TKA had both entire femurs imaged twice using a Lunar iDXA with subject repositioning between scans; the atypical femur fracture feature of enCORE software was utilized. To define femoral BMD distribution, custom 1 cm ROIs were stacked one atop the other starting at the intercondylar notch and continuing to the base of the lesser trochanter. Femur length was measured with the ruler tool to calculate distance at 5% increments. ROIs encompassing each 5% increment were utilized to measure BMD at each location. Descriptive statistics were used to determine mean BMD at each ROI and reproducibility at the 15%, 25%, 45%, 60%, and 80% ROIs. Results: The 5 and 10% ROIs included prosthetic and/or patella, causing high BMD values. Distal femur BMD was lowest at the 15% ROI and was higher (p < 0.05) at each more proximal ROI to 45%, then plateaued from 45% to 75%. BMD reproducibility at these regions was excellent; coefficient of variation (CV) from ∼1% to 3.5%. As periprosthetic fractures generally occur in the distal femur, we propose measuring femur BMD using ROIs placed at 15% and 25%. A 60% region could also be used as a highly cortical site. Conclusion: Existing DXA capabilities allow distal femur BMD measurement with good reproducibility. Further research using standardized ROIs to assess distal femur BMD loss after TKA, and interventions to mitigate this loss, is indicated. [ABSTRACT FROM AUTHOR]

External artifacts can confound dual-energy X-ray absorptiometry (DXA) measurements. It is often accepted that garments free of metal do not affect DXA results; however, little data exist in this regard. It is plausible that some textiles absorb radiation and thereby alter DXA results. We hypothesized that some dense or synthetic textiles, for example, reflective materials, might alter DXA-measured bone and soft tissue mass. Hologic and GE Lunar spine phantoms and a Bioclinica prototype total body phantom were imaged on a GE Lunar iDXA and Prodigy densitometer. Each phantom was scanned 10 times to establish mean values. Subsequently, 2 layers of various fabrics were placed over the entire top surface of the phantom, and 10 scans were performed without repositioning. Samples of natural, synthetic, or embellished fabric (including those with reflective material) and of varying thickness were used. Wilcoxon signed rank tests were used to compare the means between bare phantom and textile-covered phantom. Significant differences were demonstrated often, depending on the scanner, phantom, and textile used. A polyester fabric with reflective strip consistently altered measurements. For example, this fabric increased measured mean lumbar spine bone mineral density and total body bone mineral content by 0.008 g/cm 2 and 3.6 g, respectively ( p  < 0.01). Similarly, mean total body fat decreased (−173 g) and lean mass increased (+213 g; p  < 0.01). Fat and lean mass were also affected by metallic thread, wool, blend denim, and shiny polyester ( p  < 0.05), and lean mass was affected by cotton denim and sweatshirt material ( p  < 0.0003). In conclusion, textiles can affect DXA-measured bone mineral density and body composition results. Even small amounts of reflective material could alter mass measurements by ~25% of the least significant change. Clothing made of dense textiles (e.g., wool and denim) or those with reflective material and metallic thread should be avoided during DXA scanning. [ABSTRACT FROM AUTHOR]

Vitamin K may be important in bone metabolism. Notably, high-dose menaquinone-4 (menatetrenone, MK4) has been reported to reduce ovariectomy (ovx)-induced bone loss in rats and to decrease osteoporotic fracture in postmenopausal women. However, it is unclear whether these beneficial effects reflect a physiologic effect of vitamin K, or indicate direct pharmacologic activity of MK4. To further evaluate this, 60 6-month-old nulliparous Sprague-Dawley rats were randomized by distal femur bone mineral density (BMD) in a 3:1 ratio to ovx or sham groups. The sham and one ovx group’s diet contained 1% calcium and 1300 μg/kg of vitamin K1, phylloquinone. Diets of the other two ovx groups were supplemented with 882 mg phylloquinone or MK4 per kilogram chow. Distal femur bone mineral density (DFBMD) in an 8 mm region of interest was measured at baseline, 1 and 3 months postoperatively, utilizing dual-energy X-ray absorptiometry (DXA). All animals were killed at 3 months, their right femurs excised, ex vivo BMD measured by DXA, and biomechanical testing performed. No effect of phylloquinone or MK4 supplementation on ovx-induced bone loss was observed. Specifically, DFBMD declined 10.5%, 9.2%, and 11.2% at 1 month and 14.4%, 10.6%, and 13.9% at 3 months in the ovx control, high phylloquinone, and high MK4 groups, respectively. In addition, serum osteocalcin was elevated by ovx; this was not altered by phylloquinone or MK4. Finally, femoral biomechanical properties were not affected by phylloquinone or MK4. To conclude, in this study, neither high-dose phylloquinone nor MK4 reduced the ovx-associated increase in bone turnover or decline in DFBMD. [ABSTRACT FROM AUTHOR]

Phylloquinone (K) absorption was assessed in 22- to 30-y-old human subjects consuming a standard test meal [402 kcal (1682 kJ), 27% energy from fat]. The absorption of phylloquinone, measured over a 9-h period as the area under the curve (AUC), was higher (P < 0.01) after the consumption of a 500- microgram phylloquinone tablet [27.55 +/- 10.08 nmol/(L. h), n = 8] than after the ingestion of 495 microgram phylloquinone as 150 g of raw spinach [4.79 +/- 1.11 nmol/(L. h), n = 3]. Less phylloquinone (P < 0.05) was absorbed from 50 g of spinach (AUC = 2.49 +/- 1.11 nmol/(L. h) than from 150 g of spinach. Absorption of phylloquinone from fresh spinach (165 microgram K), fresh broccoli (184 microgram K) and fresh romaine lettuce (179 microgram K) did not differ. There was no difference in phylloquinone absorption from fresh or cooked broccoli or from fresh romaine lettuce consumed with a meal containing 30 or 45% energy as fat. [ABSTRACT FROM AUTHOR]