Implementing a fracture liaison service open model of care utilizing a cloud-based tool.

PURPOSE: Although half of women and one-quarter of men aged 50 and older will sustain an acute low-trauma fracture, less than a quarter receive appropriate secondary fracture prevention. The goal of this quality improvement demonstration project was to implement a Fracture Liaison Service (FLS) focused on secondary prevention of an osteoporotic fracture in three open health care systems aided by a cloud-based tool. METHODS: The pre-post study design examined the proportion of men and women over age 50 who received appropriate assessment (bone mineral density, vitamin D levels) and treatment (calcium/vitamin D, pharmacologic therapy) in the six months following a recently diagnosed fracture. The pre-study (Pre FLS) included a retrospective chart review for baseline data (N = 344 patients) within each health care system. In the post-evaluation (Post FLS, N = 148 patients), the FLS coordinator from each health care system examined these parameters following enrollment and for 6 months following the recently diagnosed fracture. Data were managed in the cloud-based FLS application tool. RESULTS: Ninety-three participants completed the program. The FLS program increased the percentage of patients receiving bone mineral density testing from 21% at baseline to 93% (p < 0.001) Post FLS implementation. Assessments of vitamin D levels increased from 25 to 84% (p < 0.001). Patients prescribed calcium/vitamin D increased from 36% at baseline to 93% (p < 0.001) and those prescribed pharmacologic treatment for osteoporosis increased on average from 20 to 54% (p < 0.001) Post FLS. CONCLUSIONS: We conclude that the FLS model of care in an open health care system, assisted by a cloud-based tool, significantly improved assessment and/or treatment of patients with a recently diagnosed osteoporotic fracture. Future studies are necessary to determine if this model of care is scalable and if such programs result in prevention of fractures. Mini-Abstract: The goal was to implement a Fracture Liaison Service (FLS) focused on secondary prevention of an osteoporotic fracture in open health care systems aided by a cloud-based tool. This model significantly improved assessment and/or treatment of patients with a recently diagnosed fracture.

Effect of flurbiprofen on hind-limb suspension-induced bone loss.

BACKGROUND: Prostaglandins, specifically prostaglandin E2 (PGE2), may be involved in the bone loss that occurs in microgravity. Flurbiprofen (FBP), a nonsteroidal anti-inflammatory drug (NSAID), has been shown to increase periosteal apposition rate in rats, and may inhibit bone loss by decreasing PGE2 concentrations. METHODS: A hind-limb suspension (HLS) technique was used to determine if FBP could attenuate the bone demineralization that occurs with decreased load-bearing activity. Rats were assigned to either the HLS group or the ground-based (control) group. Both of these groups were then divided into drug-treated and control subgroups (n = 10). Rats in the drug group received FBP 2 mg x kg(-1) x d(-1) subcutaneously. Study data were collected at 2 and 4 wk. The left femur of each animal was used for densitometry, and the right tibia was processed for histomorphometry. Mechanical properties of the left femur were assessed by three-point bending. RESULTS: After 2 wk, the FBP-treated rats in both the HLS and ground-based groups had 6% less bone mineral density (BMD) than did controls (p < 0.05). FBP was not effective in protecting bone from the early stages of disuse osteopenia. At 4 wk, BMD in the ground-based group was not significantly different between control and drug animals. However, in the HLS group, BMD was 11% greater in the FBP-treated group than in the control group (p < 0.05). FBP did not significantly affect the mechanical properties of bone at either 2 or 4 wk. CONCLUSION: FBP may not only affect bone demineralization by interacting with existing osteoclasts, but may also interfere with the signaling, activation, and recruitment of osteoclasts that occur after skeletal unloading.

A new twist in trypanosome RNA metabolism: cis-splicing of pre-mRNA.

It has been known for almost a decade and a half that in trypanosomes all mRNAs are trans-spliced by addition to the 5' end of the spliced leader (SL) sequence. During the same time period the conviction developed that classical cis-splicing introns are not present in the trypanosome genome and that the trypanosome gene arrangement is highly compact with small intergenic regions separating one gene from the next. We have now discovered that these tenets are no longer true. Poly(A) polymerase (PAP) genes in Trypanosoma brucei and Trypanosoma cruzi are split by intervening sequences of 653 and 302 nt, respectively. The intervening sequences occur at identical positions in both organisms and obey the GT/AG rule of cis-splicing introns. PAP mRNAs are trans-spliced at the very 5' end as well as internally at the 3' splice site of the intervening sequence. Interestingly, 11 nucleotide positions past the actual 5' splice site are conserved between the T. bruceiand T. cruzi introns. Point mutations in these conserved positions, as well as in the AG dinucleotide of the 3' splice site, abolish intron removal in vivo. Our results, together with the recent discovery of cis-splicing introns in Euglena gracilis, suggest that both trans- and cis-splicing are ancient acquisitions of the eukaryotic cell.

Syringe-mediated drug sharing among injecting drug users: patterns, social context and implications for transmission of blood-borne pathogens.

Drug injectors are at risk for infection with human immunodeficiency virus (HIV) and other blood-borne pathogens through the exchange of (infected) blood resulting from unhygienic injecting practices. Research attention and public discussion have focused primarily on the sharing of syringes and needles. While the focus on syringe sharing has sparked important interventions (bleach distribution, syringe exchange) it may have obscured the social relationship in which injecting equipment is used. Drug sharing plays a crucial role in the social organization of the drug using subculture. In this paper, various drug sharing practices and other distinguishable aspects of the injecting process-collectively termed Syringe-Mediated Drug Sharing (SMDS)-are described. All of these behaviors may put injecting drug users (IDUs) at risk for infection. The purpose of this paper is to stimulate scientific inquiry into SMDS behaviors and the social contexts which shape them. Descriptions are based primarily on field studies in Rotterdam and New York City. Recommendations for safer injecting training and education are proposed, as are directions for future research.

The effects of gallium nitrate on osteopenia induced by ovariectomy and a low-calcium diet in rats.

The effects of gallium nitrate (GN) were evaluated on osteopenia induced by ovariectomy (OVX) and a low-calcium diet (LCD) in Sprague-Dawley rats. Twenty-five rats (300-400 g) were randomized into four groups of 5-7 animals: (I) OVX LCD treated with GN for 22 weeks; (II) OVX LCD treated with GN for 10 weeks; (III) OVX LCD treated with saline; and (IV) sham-operated (SO), normal diet, treated with saline. GN-treated rats received a 30-mg/kg subcutaneous single dose of elemental gallium, followed by 10 mg/kg per week, whereas control animals received an equal volume of saline. All animals were euthanized at 22 weeks. Measurements of bone density and histomorphometry, performed on the proximal portion of the tibia, indicated significant bone loss in all OVX LCD animals. GN-treated rats in group I gained significantly less weight than those in the other groups, and their blood urea nitrogen increased, suggesting a nephrotoxic effect. After discontinuation of GN, rats in group II gained weight at the same rate as those which had received only saline. Bone formation rates in the GN-treated rats were double those of the saline-treated OVX animals and more than 10 times those of SO controls. Although the bone formation rate in GN-treated rats increased, GN had no effect in preventing the loss of bone surface, density and volume induced by OVX LCD. These findings suggest that although GN may enhance osteoblastic activity, this agent alone does not appear effective in the prevention of bone loss induced by OVX LCD.

Effects of aminohydroxybutane bisphosphonate on bone growth when administered after hind-limb bone loss in tail-suspended rats.

The effects of aminohydroxybutane bisphosphonate (AHBuBP) on bone after disuse osteopenia were studied in tail-suspended rats. Male Sprague-Dawley rats (weight range, 313-352 g) randomized into four groups of eight animals received 2 ml kg-1 day-1 of either AHBuBP (0.3 mg kg-1 day-1) or normal saline (vehicle) subcutaneously on days 14 and 15 of a 28-day experiment. The groups were 1) nonsuspended, saline; 2) suspended on days 14 to 28, saline; 3) suspended on days 0 to 28, AHBuBP; and 4) suspended on days 0 to 28, saline. On days 19 and 26, all rats received 15 mg/kg (1 ml/kg) of calcein. On day 28, they were sacrificed and their tibias and femurs were analyzed in vitro for bone density, strength and stiffness. The tibias were also analyzed histomorphometrically. The tibias and femurs from AHBuBP-treated rats were as dense as those in the nonsuspended group, whereas tail suspension in the untreated rats for 14 and 28 days caused a significant decrease in bone density. However, in measurements of bone strength and stiffness, the samples from the rats that received AHBuBP were similar to those of untreated rats suspended for 14 days, suggesting the newly formed bone was weaker. In the AHBuBP group, compared with all others, static histologic measurements of the proximal tibial metaphyses showed an increased bone area and perimeter and a decreased percentage of osteoid perimeter without a difference in the percentage of eroded perimeter. Dynamic histologic studies showed a decreased bone formation rate and decreased longitudinal growth rate.(ABSTRACT TRUNCATED AT 250 WORDS)

Aminohydroxybutane bisphosphonate and clenbuterol prevent bone changes and retard muscle atrophy respectively in tail-suspended rats.

Hind-limb unloading by tail suspension of rats, an established model of simulated microgravity, was used to examine the efficacy of aminohydroxybutane bisphosphonate (AHBuBP) and clenbuterol in preventing bone loss and muscle atrophy, respectively. Male Sprague-Dawley rats (299-372 g) were randomized into six groups of six: 1) unsuspended, saline, 2) unsuspended, saline, pair fed with group 3, 3) suspended, saline, 4) suspended, 0.03 mg/kg/day x 2 of AHBuBP, 5) suspended, 0.3 mg/kg/day x 2 of AHBuBP and 6) suspended, 0.3 mg/kg/day x 2 of AHBuBP + clenbuterol (0.5 mg/kg/day i.p. x 6, then 1 mg/kg/day i.p. x 6). Animals in groups 3 to 6 were tail suspended for 14 days from a system of double pulleys and allowed free mobility with their hind limbs unloaded. On days -2 and -1, before suspension on day 0, all rats received a single s.c. injection of either 2 ml/kg of normal saline (vehicle) or AHBuBP. All rats were tested for exercise tolerance before day -2 and on day 10, and grip strength before day -2 and on day 13. On day 14, the rats were euthanized and their humeri, tibias and femurs analyzed in vitro for bone density (by single-photon absorptiometry), strength and stiffness (by 3-point bending). Muscles were analyzed for weight, protein concentration and enzyme activity. Pair feeding had no effect other than on food consumption and body weight. AHBuBP caused a dose-dependent increase in bone density in humeri, tibias and femurs, even in tail-suspended rats, relative to control unsuspended animals, with no significant difference in bone strength or stiffness between AHBuBP groups and unsuspended animals.(ABSTRACT TRUNCATED AT 250 WORDS)

Drug use contexts and HIV-consequences: the effect of drug policy on patterns of everyday drug use in Rotterdam and the Bronx.

Epidemiological data on HIV seroprevalence has been essential in assessing the (future) extent of the AIDS epidemic. By coupling these data with quantifiable variables related to injection drug use (frequency of injecting, number of needle sharing partners) specific 'risk behaviors' could be determined, accounting for the rapid spread of the virus in the injecting drug user (IDU) population. Yet, such data give little information on the social mechanisms and setting generating such risk behaviors. In order to understand the transmission of HIV among the IDU population one needs to study the micro settings and social context of drug use. This paper describes and explores certain patterns of drug use, sharing, and natural support systems found amongst IDUs in two very different cities, Rotterdam (The Netherlands) and the Bronx, New York City (USA). By specifying details of the micro-settings of everyday drug use in both locales, it is possible to identify certain common elements and consequences of personal and social behavior driven by drug use per se (e.g. drug preference), and to differentiate these from behaviors and consequences determined by drug policy and the social context in which drug use actually occurs. These policies and the social context they create can in turn be shown to relate to risks for HIV transmission, e.g. the increased likelihood of sharing injection equipment. A more careful ethnographic approach, taking advantage of natural experimental opportunities, comparisons and controls, may be utilized to examine drug-related behaviors in their social context and to better assess their relevance to public health--especially to AIDS.

Femoral component loosening in hip arthroplasty. Cadaver study of subsidence and hoop strain.

To aid in understanding loosening following cemented total hip arthroplasty, we conducted a cadaver study of the proximal femur with implanted cobalt-chromium and titanium femoral components of recent design, loaded through the head of the prosthesis. Stem subsidence and strain in the proximal femur were measured. After proximal support of the implant collar was removed, we found that cobalt-chromium implants had a greater tendency to subside than titanium implants. Subsidence of a femoral component within the cement mantle caused an increase in tensile hoop strain measured in the proximal cortex. When implants were loaded until failure of the cortex, a direct relationship between increase in subsidence and increase in cortical hoop strain was demonstrated. Our data show that implants that resist subsidence into the cement mantle tend to decrease hoop strains in the proximal femoral cortex.

Effects of repetitive loading on the integrity of porous coatings.

In spite of the increasing numbers of porous coated total hip femoral components implanted each year, little is known about the shear strength or fatigue performance of the interface between coating and implant substrate. The appearance of loose beads in clinical follow-up roentgenograms suggests that shear failure of bead welds does occur and that the coating could be a weak link in the implant-bone or implant-cement-bone system. In this study, a test specimen design and test regimen for quasistatic and fatigue testing of implant-porous coating shear properties was developed. Both cobalt-chromium (CoCr) alloy and titanium (Ti) bead-substrate interfaces of various surface designs were studied. Results showed that static bead-substrate interface properties for both titanium and CoCr specimens were superior to published values of bone-bead shear strengths. By comparison, fatigue tests showed that the strength of bead welds on a smooth substrate was inadequate, with a preferential failure site being between beads and substrate rather than between beads and cement or beads and bone. However, implant surface contours or a bead recess were found to protect the bead welds, and specimens with those features successfully withstood ten million dynamic loading cycles.

Evaluation of double-exposure holographic interferometry for biomechanical measurements in vitro.

Double-exposure holographic interferometry is a nondestructive testing technique for measuring displacement and strain in a test object. A standard hologram contains three-dimensional information about an object. However, the holographic interferogram has additional information, as a series of interference bands overlaid on the three-dimensional image of the object contains information about object deformation. Interferograms were produced for intact cadaveric femora and cadaveric femora with implanted titanium alloy and cobalt-chromium alloy femoral components. A force was applied to the femoral head to simulate single leg stance, and changes in specimen deformation were observed as additional incremental loads were applied. We have observed that the femur behaves as a bending beam and that the holographic technique allows the position of maximal deflection to be identified and the magnitude of femoral displacement from the load axis to be determined at any point within the field of view. The effects of the modulus of the implanted stem on the bending characteristics of the composite structure were clearly seen in the interferograms. This communication presents a photographic analysis of the double exposure interferograms recorded, as well as a critique of the technique for biomechanical measurements in vitro.

Holographic interferometry: a critique of the technique and its potential for biomedical measurements.

Double-exposure holographic interferometry is a contactless whole-field method. Dimensional changes are visualized as a series of interference fringes overlaid on the holographic image of the femur, where each fringe represents 0.316 micron (half the wavelength of the laser light) of motion. Interferograms for intact femora and for femora with identical geometry prostheses were produced. We have shown that the femur bends as a beam under axial load. The position of maximum deflection is a function of the properties of the composite structure. Under a known load the amount of deflection can be calculated and the effect of the prosthesis's modulus can be ascertained. In addition to bending, rotational effects can be perceived. Although data interpretation is complex and holographic production is costly and time-consuming, the technique holds promise for biomechanical applications as well as other biomedical disciplines.

Talectomy in the treatment of resistant talipes equinovarus deformity in myelomeningocele and arthrogryposis.

Eighteen patients (28 feet) with spina bifida and arthrogryposis had talectomy for correction of severe equinovarus deformity. In 26 feet, posteromedial release had been performed previously. The average age at surgery was 4 1/2 years, with a range of 1-9 years of age. The length of follow-up averaged 4 years and ranged from 12 months to 8 years. Twenty-three feet were rated good, and five were poor. Six feet, because of forefoot adduction, required further surgery (metatarsal osteotomy). Talectomy is an effective procedure for correction of hindfoot deformity. Forefoot problems must be treated as a separate entity.

The load carrying and fatigue properties of the stem-cement interface with smooth and porous coated femoral components.

Porous coated surfaces for fixation of total hip replacement are a current trend in clinical orthopedics. Such devices are designed to be fixed by ingrowth of bony tissue, although in the absence of FDA approval for biologic fixation, fixation with PMMA cement is recommended by the implant manufacturers. In order to characterize the mechanical properties of the micro-interlocked stem-cement interface, we tested both porous coated and smooth femoral components in cement mantles of consistent overall geometry. Under conditions of increasing load the smooth stems demonstrated stepwise irreversible subsidence into the mantle. Axial and circumferential strains measured in the cement containment vessels with the smooth stems showed that stepwise increases in tensile hoop strain occurred concomitantly with the stepwise incidents of stem subsidence. When subjected to the same loading conditions, the porous coated stems did not undergo stepwise incidents of subsidence, and hoop strain generation was reduced. In addition, a twofold increase in the failure load of the stem-cement interface was measured with the porous coated stems. Fatigue loading for 10(7) loading cycles did not result in gross failure of either the micro-interlocked or smooth interfaces. However, the data showed that during fatigue loading, stepwise subsidence of the smooth stems again occurred. The final subsidence magnitude of the smooth stem-cement interface at 10(7) loading cycles was six times greater than the value associated with the porous coated stem. Thus the porous coating of femoral stems was shown to dramatically improve the load carrying capability and fatigue characteristics of the stem-cement interface.

Qualitative and morphometric evaluation of vocal cord lesions produced by the carbon dioxide laser.

The canine larynx was studied to obtain qualitative and quantitative data accurately defining the destructive effects of the carbon dioxide laser on epithelial tissue by administering doses of varied energy to the dorsal surface of the vocal cords. Resultant lesions subsequently were analyzed by light, transmission, and scanning microscopy. Three major morphologic patterns of vocal cord lesions were observed: 1. cup shape, 2. doughnut shape and, 3. complex star shape. The patterns produced in the laryngeal tissue reflect the operative mode (energy distribution within the focused spot of energy) of the laser at the time of surgery. The mode resulting in the doughnut shaped pattern (energy distribution around the periphery of the spot) produced deepest lesions, with minimal thermal conduction laterally, whereas the mode resulting in the cup-shaped pattern (energy distribution uniform throughout the spot) produced at comparable doses shallower lesions with larger diameter. Too few star-shaped patterns were observed to permit meaningful morphometric analysis.