Factors associated with non-walking 4 months after hip fracture. A prospective study of 23,759 fractures.

INTRODUCTION: Despite advances in new surgical techniques and improvements in medical care of the last decades a considerable number of patients will not regain their ability to walk after a hip fracture. AIMS: To further identify risk factors associated with non-walking 4-months after a hip fracture. MATERIAL AND METHODS: Register-based, longitudinal study with a 4-month follow-up. The collected data from the Swedish hip fracture registry, RIKSHÖFT, contained all hip fracture between 201301-01-2015-12-31 in Sweden. All patients older than 50 years with a non-pathological fracture and who were able to walk before the fracture were included. The association of sex, age, general health, dementia and type of discharge with complete loss of walking after a hip fracture were investigated using a multivariate analysis. RESULTS: Included were 23,759 patients. At the 4-month follow-up, 10% were unable to walk. Twenty-five per cent of patients with dementia lost their ability to walk compared to 7% of those with no cognitive dysfunction. Adjusted odds ratio (OR) for factors associated with loss of walking ability were; discharge to institutionalized care rather than their own home or a rehabilitation unit (OR=1.91; 95% CI=1.67-2.18), dementia (OR=1.80; 95% CI=1.57-2.06), male gender (OR=1.59; 95% CI=1.40-1.81) and ASA score grade III-V (OR=1.37; 95% CI=1.20-1.55) but not age (OR=1.01; 95% CI=1.00-1.02). CONCLUSIONS: An important factor associated with a complete loss of walking ability after a hip fracture is the discharge to institutionalized care. This factor might be influenced either by favouring rehabilitation units or by improving the rehabilitation protocols.

Descripción de un brote polimicrobiano en una unidad de cuidados intensivos durante la ola pandémica de COVID-19 de marzo de 2020 / No disponible

INTRODUCCIÓN: La ola pandémica de COVID-19 de marzo de 2020 mermó las medidas de control de infección en las UCI. Se describe un brote polimicrobiano, sus posibles factores de riesgo, relación con la COVID-19 y medidas que facilitaron su control. MÉTODOS: estudio observacional longitudinal retrospectivo. RESULTADOS: se estudiaron 149 pacientes, 23 casos presentaron microorganismos de interés, 9 más de uno. Se aislaron 15 Klebsiella pneumoniae BLEE, 5 KPC, 8 hongos filamentosos y 5 bacilos gramnegativos no fermentadores. La tasa de ataque fue de 0,154 siendo superior para ingresos COVID-19 (0,262) frente a otros motivos (0,015), con una diferencia de 0,247 (0,148-0,345; p < 0,001). Se implementaron medidas de control sobre los riesgos detectados. CONCLUSIÓN: ser paciente COVID-19 se asoció con mayor riesgo de ser caso, consideramos como posibles desencadenantes el mayor contacto requerido con equipos de protección y la pérdida temporal de control sobre la multirresistencia, tanto de información como de competencia

INTRODUCTION: The pandemic wave of COVID-19 in March 2020 undermined compliance with infection control measures in ICUs. A polymicrobial outbreak, its possible risk factors, relationship with COVID-19 and measures that facilitated its control are described. METHODS: retrospective longitudinal observational study. RESULTS: 149 patients were studied, 23 cases presented microorganisms of interest, 9 more than one. 15 Klebsiella pneumoniae ESBL, 5 KPC, 8 filamentous fungi and 5 non-fermenting gram-negative bacilli were isolated. The attack rate was 0.154, being higher for patients admitted for COVID-19 (0.262) compared to other reasons (0.015), with a difference of 0.247 (0.148-0.345; p < 0.001). Control measures were implemented on the risks detected. CONCLUSION: being a COVID-19 patient was associated with a higher risk of being a case, we consider as possible triggers the greater contact required with protective equipment and the temporary loss of control over multidrug resistance, both of information and of competence

Morphogenesis in robot swarms.

Morphogenesis allows millions of cells to self-organize into intricate structures with a wide variety of functional shapes during embryonic development. This process emerges from local interactions of cells under the control of gene circuits that are identical in every cell, robust to intrinsic noise, and adaptable to changing environments. Constructing human technology with these properties presents an important opportunity in swarm robotic applications ranging from construction to exploration. Morphogenesis in nature may use two different approaches: hierarchical, top-down control or spontaneously self-organizing dynamics such as reaction-diffusion Turing patterns. Here, we provide a demonstration of purely self-organizing behaviors to create emergent morphologies in large swarms of real robots. The robots achieve this collective organization without any self-localization and instead rely entirely on local interactions with neighbors. Results show swarms of 300 robots that self-construct organic and adaptable shapes that are robust to damage. This is a step toward the emergence of functional shape formation in robot swarms following principles of self-organized morphogenetic engineering.

Treatment of full thickness focal cartilage lesions with a metallic resurfacing implant in a sheep animal model, 1 year evaluation.

BACKGROUND: Full depth focal cartilage lesions do not heal spontaneously and while some of these lesions are asymptomatic they might progress to osteoarthritis. Treatment for these lesions is warranted and the gold standard treatment at younger age remains biological healing by cell stimulation. In the middle-age patient the success rate of biologic treatment varies, hence the surge of non-biological alternatives. Our objective was to evaluate the efficacy and safety of a metallic implant for treatment of these lesions with respect to the long-term panarticular cartilage homeostasis. METHODS: The medial femoral condyle of 16 sheep was operated unilaterally. A metallic implant was inserted in the weight-bearing surface at an aimed height of 0.5 mm recessed. Euthanasia was performed at 6 or 12 months. Implant height and tilt was analyzed using a laser-scanning device. Damage to cartilage surfaces was evaluated macroscopically and microscopically according to the Osteoarthritis Research Society International (OARSI) recommendations. RESULTS: Thirteen sheep were available for evaluation and showed a varying degree of cartilage damage linearly increasing with age. Cartilage damage of the medial tibial plateau opposing the implant was increased compared to the non-operated knee by 1.77 units (p = 0.041; 95% CI: 0.08, 3.45) on a 0-27 unit scale. Remaining joint compartments were unaffected. Implant position averaged 0.54 recessed (95% CI: 0.41, 0.67). CONCLUSIONS: Our results showed a consistent and accurate placement of these implants at a defined zone. At this position cartilage wear of opposing and surrounding joint cartilage is limited. Thus expanded animal and human studies are motivated.

Fixation of a double-coated titanium-hydroxyapatite focal knee resurfacing implant: a 12-month study in sheep.

OBJECTIVE: Focal cartilage lesions according to International Cartilage Repair Society (ICRS) grade 3-4 in the medial femoral condyle may progress to osteoarthritis. When treating such focal lesions with metallic implants a sound fixation to the underlying bone is mandatory. We developed a monobloc unipolar cobalt-chrome (Co-Cr) implant with a double coating; first a layer of commercially pure titanium (c.p.Ti) on top of which a layer of hydroxyapatite (HA) was applied. We hypothesised that such a double coating would provide long-lasting and adequate osseointegration. DESIGN (MATERIALS AND METHODS): Unilateral medial femoral condyles of 10 sheep were operated. The implants were inserted in the weight-bearing surface and immediate weight-bearing was allowed. Euthanasia was performed at 6 (three animals) or 12 months (six animals). Osseointegration was analysed with micro-computer tomography (CT), light microscopy and histomorphometric analyses using backscatter scanning electron microscopy (B-SEM) technique. RESULTS: At 6 months one specimen out of three showed small osteolytic areas at the hat and at 12 months two specimens out of six showed small osteolytic areas at the hat, no osteolytical areas were seen around the peg at any time point. At both time points, a high total bone-to-implant contact was measured with a mean (95% confidence interval - CI) of 90.6 (79-102) at 6 months and 92.3 (89-95) at 12 months, respectively. CONCLUSIONS: A double coating (Ti + HA) of a focal knee resurfacing Co-Cr implant was presented in a sheep animal model. A firm and consistent bond to bone under weight-bearing conditions was shown up to 1 year.

Focal knee resurfacing and effects of surgical precision on opposing cartilage. A pilot study on 12 sheep.

BACKGROUND: Full thickness cartilage lesions (ICRS grade 3-4) and focal lesions of degenerative origin may progress to osteoarthritis (OA). Such focal lesions can be treated by metallic implants. We hypothesized that such treatment results in opposing surface cartilage damage that correlates with implant position (height) relative to the adjacent cartilage surface. This relationship was investigated using a sheep animal model. METHODS: Both medial femoral condyles of 12 sheep were operated. The implants, were inserted in the weight-bearing surface at different heights relative to the surrounding cartilage. Euthanasia was performed at 6 or 12 weeks. After retrieval, implant height was analyzed using laser scanning. Damage to the opposing tibial cartilage was evaluated macroscopically and microscopically according to the modified Mankin score. RESULTS: Twenty-two knees were available for evaluation and showed cartilage lesions ranging from severe damage (Mankin stage 11) to almost pristine conditions (Mankin stage 1). There was a strong correlation between implant height and cartilage damage. Standard deviation from the aimed implant height was 0.47 mm. CONCLUSIONS: Our results showed significant surgical imprecision and protruding implants imposed severe cartilage damage. We therefore suggest implants should be placed recessed (approx. 0.5 mm) below the surrounding cartilage in this animal model. These results encourage further studies of metallic implants yet the utmost precision regarding position is required.

Persisting muscle atrophy two years after replacement of the hip.

Muscle atrophy has been demonstrated in patients suffering from osteoarthritis of the hip, but little is known about muscular recovery after total hip replacement (THR). A total of 20 patients with unilateral osteoarthritis of the hip were assessed before, six months and two years after THR. The cross-sectional area and radiological density of the muscles of the hip, thigh, calf and back were measured using CT. We hypothesised that the muscles would not recover fully after operation. After two years comparison of the limb with the THR with the healthy limb showed that there was such a reduction in the cross-sectional area in iliopsoas (7.0%; p = 0.006) and the hip adductors (8.4%, p = 0.003) and in the radiological density in gluteus maximus (10.1 Hounsfield units; p < 0.001), gluteus medius/minimus (5.6 Hounsfield units; p = 0.011), iliopsoas (3.9 Hounsfield units; p < 0.001) and the adductors (2.4 Hounsfield units; p = 0.022). Thus, there was persistent muscle atrophy in muscles acting about the hip two years after THR. We suggest that an earlier operation or a more intensive rehabilitation may reverse these changes.

Differential attachment of oral treponemes to monolayers of epithelial cells.

This in vitro study describes the attachment properties of several oral treponemes to monolayers of epithelial cells and the effect of epithelial cell confluence on treponeme attachment. Four serotypes of Treponema denticola, Treponema scoliodontum, three subspecies of Treponema socranskii, and Treponema vincentii were tested with monolayers of epithelial cells of human and canine origin. Attachment of oral treponemes were compared to attachment by T. pallidum subsp. pallidum, and by the non-pathogen Treponema phagedenis. Results indicated that different serotypes of T. denticola had similar abilities to attach to epithelial cells. However, subspecies of T. socranskii differed in their ability to attach to epithelial cells. The proportion of epithelial cells susceptible to attachment by oral spirochetes was strongly related to the confluence level of the monolayer. In contrast, T. pallidum attached equally well to both epithelial cell lines at all confluence levels. T. phagedenis attached to < 1% of all epithelial cells. In general, attachment of oral treponemes to canine cells was lower than to human cells, suggesting species-specificity for adherence. Attachment of oral treponemes to epithelial cells may promote colonization of the periodontal pocket, as well as retention of treponeme colonies within plaque. The preference of oral treponemes to attach to cells of low confluence fields may translate in vivo to an increased ability to attach to cells which are actively dividing. Such cells are found in areas of repair, a common status within inflamed periodontal pockets. Furthermore, attachment of oral treponemes to epithelial cell barriers may promote or potentiate cytopathic processes.

Associations between Porphyromonas gingivalis and oral treponemes in subgingival plaque.

Colonization and/or proliferation of Treponema denticola may depend on the presence of Porphyromonas gingivalis. The aims of this study were to confirm this synergistic relationship, to determine whether other oral bacteria were similarly associated with P. gingivalis and to relate coinfection to the periodontal status of plaque donors. Subgingival plaque was collected from every tooth except third molars in 106 subjects who were grouped by their worst periodontal condition. In addition to P. gingivalis, monoclonal antibodies were used to identify Campylobacter rectus, Eikenella corrodens, T. denticola, Treponema socranskii and pathogen-related oral spirochetes. Associations of these bacteria with coinfection by P. gingivalis were assessed by estimated odds ratios. The results indicate that coinfection with P. gingivalis is linked to all tested bacteria, but each pair was associated with distinct periodontal conditions. The distribution of coinfected sites suggests biased colonization of facial surfaces over lingual surfaces.

Subgingival distribution of Treponema denticola, Treponema socranskii, and pathogen-related oral spirochetes: prevalence and relationship to periodontal status of sampled sites.

Aims of this study were to comprehensively describe the intraoral distribution of the spirochete morphogroup and of 7 antigenically distinct oral treponema, and to relate their presence to periodontal status. Periodontal tissues were evaluated at 4 sites on every tooth except third molars and 76 subjects were classified according to the worst periodontal condition at any one site: Group 1, gingivitis (n = 13); Group 2, early periodontitis (n = 38); and Group 3, advanced periodontitis (n = 25). Subgingival plaque was collected from each half of every tooth evaluated clinically. Spirochetes were identified with phase contrast microscopy and specific treponema were detected immunochemically using monoclonal antibodies to Treponema denticola serovars A-D, T. socranskii subspecies bucalle, T. socranskii subspecies socranskii, and T. pallidum (pathogen-related oral spirochetes, PROS). The counting protocol was conservative and probably underestimated the actual presence of organisms. Spirochetes were found at one or more sites in approximately 60% of subjects in all groups. PROS were found in approximately 40% of subjects in all groups while T. denticola (predominantly serotype B) and T. socranskii (exclusively T. socranskii subsp. buccale) were more frequently observed in Group 2 (roughly 25% for both treponema) than in Groups 1 or 3. Overall, spirochetes were detected in less than 15% of the 4,040 sites examined. Spirochetes were found at more sites of periodontitis (group mean range 20 to 40%) than of gingivitis (6 to 20%), and were only infrequently found at sites of periodontal health (4 to 10%). Spirochetes were identified most often in plaque from around molars and they were usually found in only one of two samples from individual teeth. Results of this study suggest that although spirochetes are most often found associated with periodontitis, their distribution is restricted and most periodontitis sites do not harbor spirochetes.