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Indonesia is the world's third largest cocoa producer, but production is decreasing since 2011. We revisited cocoa farmers for an environmental assessment in Luwu Timur, Sulawesi, 7 months after a socio-economic survey on cocoa certification outcomes and observed many cocoa plantations being converted into oil palm and maize. Including our field data as well as secondary data on commodity prices and yields, we outline reasons for cocoa conversion, potential consequences for biodiversity, and assess the future outlook for the Indonesian cocoa sector. Low cocoa productivity, volatile cocoa prices and higher revenue for oil palm, among others, drive land-use change. If shade trees are cut during cocoa conversion, it may have negative implications for biodiversity. Solutions to low soil fertility, omnipresent pests and diseases, and stable producer prices are needed to increase profitability of cocoa and prevent conversion of cocoa agroforests to oil palm monocultures.
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BACKGROUND: In case of isolated medial and patellofemoral joint arthritis, bicompartmental knee arthroplasty (BCA) is an alternative to total knee arthroplasty (TKA). The purpose of our prospective, randomized study is to compare the clinical outcome of BCA vs TKA. METHODS: Eighty patients with isolated medial and patellofemoral osteoarthritis were randomly assigned to either BCA or TKA. Patients were evaluated preoperatively, 3, 6, and 12 months, and 2 and 5 years after the procedure. Knee Society Score, Oxford Knee Score, and the University of California,Los Angeles activity scores were calculated at each follow-up; Forgotten Joint Score was assessed at final follow-up. RESULTS: There was an improvement in Knee Society Score, Oxford Knee Score, and the University of California,Los Angeles scores in both groups but no significant differences between both groups at any follow-up. The Forgotten Joint Score at 5-year follow-up was not significantly different either. Range of motion was significantly greater in the BCA group from 1-year follow-up onward. CONCLUSION: Our study did not show significant differences in clinical scores between BCA and TKA; only range of motion was significantly greater in BCA. Therefore, it is questionable whether this difference justifies the complexity of BCA associated with higher risk of failure. Maybe staged patellofemoral joint arthroplasty in the presence of a well-functioning UKA is an option for BCA and an alternative to revision to TKA. Long-term studies are needed to explore the potential benefits of BCA.
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Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Osteoartritis de la Rodilla , Estudios de Seguimiento , Humanos , Articulación de la Rodilla/cirugía , Osteoartritis de la Rodilla/cirugía , Estudios Prospectivos , Rango del Movimiento Articular , Resultado del TratamientoRESUMEN
BACKGROUND: Reported survival rates of unicondylar knee arthroplasty (UKA) vary considerably. The influences of patient characteristics and the type of implant have already been examined. This analysis investigated the influence of hospital volume on 5-year-survival rate, using administrative claims data of Germany's largest health insurance provider. METHODS: We analysed administrative claims data for 20,946 UKAs covered by the German local healthcare funds (Allgemeine Ortskrankenkasse, AOK) between 2006 and 2012. Survival rates were estimated using Kaplan-Meier analysis. The influence of hospital case numbers on 5-year survival was analysed by means of multivariable Cox regression adjusted for patient characteristics. We estimated hazard ratios (HR) with 95% confidence intervals for five hospital volume categories: < 12 cases, 13â-â24 cases, 25â-â52 cases, 53â-â104 cases, > 104 cases (per hospital and year). RESULTS: The overall 5-year Kaplan-Meier survival rate was 87.8% (95%-CI: 87.3â-â88.3%). This increased with hospital volume (< 12 cases: 84.1% vs. > 104 cases: 93.2%). The analysis identified low hospital volume as an independent risk factor for surgical revision (< 12 cases: HR = 2.13 [95%-CI 1.83â-â2.48]; 13â-â24 cases: HR = 1.94 [95%-CI: 1.67â-â2.25]; 25â-â52 cases: HR = 1.66 [95%-CI: 1.41â-â1.96]; 53â-â104 cases: HR = 1.51 [95%-CI: 1.28â-â1.77]; > 104 cases: reference category). DISCUSSION: Our analysis revealed a significant relationship between hospital case numbers and 5-year survival rate, which increases with hospital volume. The risk of surgical revision within 5 years in hospitals with fewer than 25 UKAs per year is approximately twice as high as in hospitals with more than 104 cases.
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Artroplastia de Reemplazo de Rodilla/estadística & datos numéricos , Competencia Clínica/estadística & datos numéricos , Tamaño de las Instituciones de Salud/estadística & datos numéricos , Estimación de Kaplan-Meier , Falla de Prótesis , Anciano , Femenino , Alemania , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/cirugía , Reoperación/estadística & datos numéricos , Factores de RiesgoRESUMEN
BACKGROUND: Avascular necrosis after arthroscopic surgery of the knee has already been published. The purpose of this article is to report on the frequently misdiagnosed entity of osteonecrosis of the medial tibial plateau. CASE PRESENTATION: Charts and radiographs of a consecutive series with isolated medial tibial plateau osteonecrosis were analyzed. The criterion for inclusion was the absence of trauma. Six caucasian female patients with an average age of 76.5 years complied with this criterion. Three of these cases had had arthroscopic intervention for medial meniscal lesion within the previous year. CONCLUSIONS: The etiology of these necroses remains unclear. Osteonecrosis must be taken into account as a possible cause of persistent knee pain after surgery. Correlation between arthroscopic treatment and necrotic processes in the tibial plateau must still be regarded with skepticism.
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Artroplastia de Reemplazo de Rodilla/efectos adversos , Articulación de la Rodilla/patología , Meniscos Tibiales/patología , Osteonecrosis/patología , Tibia/patología , Absorciometría de Fotón , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Femenino , Humanos , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Imagen por Resonancia Magnética , Meniscos Tibiales/diagnóstico por imagen , Osteonecrosis/diagnóstico por imagen , Osteonecrosis/etiología , Complicaciones Posoperatorias , Radiografía , Tibia/diagnóstico por imagenRESUMEN
INTRODUCTION: Major bone defects are the greatest challenge in hip revision arthroplasty. METHODS: In a prospective, consecutive nonrandomised study we followed up 74 patients with Type III (AAOS) acetabular bone defects who underwent revision hip arthroplasty with bone grafting and implantation of a Burch-Schneider anti-protrusion cage (APC). The patients were examined pre- and postoperatively according to a standardised clinical and radiological protocol. No patient was lost to follow-up. RESULTS: 9 patients died before follow-up. In 9 other patients the APC was revised within the follow-up period. In 4 of these patients the revision was necessary because of aseptic loosening. In the remaining 5 cases joint infection, recurrent dislocation and 1 trauma were the reasons for revision. 56 patients were included in the statistical analysis. In the follow-up group the mean Harris Hip Score increased from 39.9 preoperatively to 73.2. 85% of the patients assessed their operation result as good or excellent. CONCLUSIONS: In a large consecutive series the Burch-Schneider anti-protrusion cage proved to be a valuable option in the treatment of major acetabular bone defects in hip revision surgery.
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Artroplastia de Reemplazo de Cadera/métodos , Trasplante Óseo/métodos , Necrosis de la Cabeza Femoral/cirugía , Luxación de la Cadera/cirugía , Prótesis de Cadera , Osteoartritis de la Cadera/cirugía , Acetábulo/cirugía , Artroplastia de Reemplazo de Cadera/instrumentación , Femenino , Estudios de Seguimiento , Humanos , Masculino , Estudios Prospectivos , Diseño de Prótesis , ReoperaciónRESUMEN
The clinical and radiological results of Vancouver type B2 and B3 peri-prosthetic fractures treated with an uncemented Wagner revision stem (3rd generation) were analysed. Two groups were identified, 15 patients had a B2 and 14 cases a B3 periprosthetic fracture. The mean follow-up was 74 months after the index operation. All fractures had united radiographically. No cases of non-union were found. There was only one case of aseptic loosening. The clinical scores presented encouraging results for both groups. The uncemented distal fixation stem was an effective solution in the treatment of type B2 and B3 periprosthetic femur fractures at mid-term follow up.
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Artroplastia de Reemplazo de Cadera/instrumentación , Fracturas del Fémur/cirugía , Prótesis de Cadera , Fracturas Periprotésicas/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Artroplastia de Reemplazo de Cadera/métodos , Cementación , Femenino , Fracturas del Fémur/diagnóstico por imagen , Curación de Fractura , Estado de Salud , Articulación de la Cadera/diagnóstico por imagen , Articulación de la Cadera/fisiopatología , Articulación de la Cadera/cirugía , Humanos , Masculino , Persona de Mediana Edad , Fracturas Periprotésicas/diagnóstico por imagen , Diseño de Prótesis , Falla de Prótesis , Radiografía , Recuperación de la Función , Reoperación , Resultado del TratamientoRESUMEN
INTRODUCTION: Anteroposterior pelvic radiographs are routinely used to monitor cup orientation in total hip arthroplasty (THA). Analysis of planar radiographs leads to a certain degree of measurement error for the cup anteversion (AV). With the current study, we wanted to clarify whether planar radiography can be used for accurate evaluation of the THA position. MATERIALS AND METHODS: The postoperative orientation of pelvic implants in 42 patients was analyzed according to five documented mathematical algorithms using planar radiographs. Postoperative computed tomography (CT) pelvis scans were available for all patients. A CT-based navigation system was used to determine AV. RESULTS: The comparison showed that all five formulas presented substantial variations for the AV angle. Of these, Widmer's algorithm presented the smallest difference compared to the CT. Misinterpretation of postoperative planar radiographs is a common problem in THA. CONCLUSION: Planar radiographs are too imprecise for exact evaluation of the correct cup AV after THA. CT-based analysis may be necessary if exact values are required.
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Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Tomografía Computarizada por Rayos X , Errores Diagnósticos , Femenino , Humanos , Masculino , Matemática , Estudios RetrospectivosRESUMEN
AIM: Does the pressfit anchorage of cementless acetabular cups depend on the roughness of the pole? To answer this question the primary pressfit of two cementless acetabular cups which differ only with regard to the roughness of their poles were compared by means of finite elements analysis. MATERIALS AND METHODS: It was assumed that the material properties of bone are homogeneous, isotropic and linearly elastic. Material-specific values of cancellous bone with three different bone densities were used. Assumption of isotropy represents an approximation. RESULTS: Comparison of the two prosthesis designs revealed that both designs/shapes cause similar patterns of bone deformation and tension. CONCLUSIONS: It can therefore be concluded that with regard to pressfit anchorage the prosthesis with milled polar surface is according to FEA mechanically equivalent to the prosthesis with non-milled polar surface.
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Acetábulo/fisiología , Artroplastia de Reemplazo de Cadera/instrumentación , Artroplastia de Reemplazo de Cadera/métodos , Diseño Asistido por Computadora , Análisis de Falla de Equipo/métodos , Acetábulo/cirugía , Cementación , Análisis de Elementos Finitos , Fricción , Dureza , Humanos , Presión , Diseño de Prótesis , Estrés Mecánico , Propiedades de SuperficieRESUMEN
Long-acting third-generation dihydropyridine calcium channel blockers (CCBs) improve endothelial dysfunction and prevent cardiovascular events in humans, but their cellular and molecular mechanisms of tissue protection are not elucidated in detail. We assessed organ (renal) protection by the highly lipophilic CCB lercanidipine in a double-transgenic rat (dTGR) model with overexpression of human renin and angiotensinogen genes. We randomly treated dTGR with lercanidipine (2.5 mg/kg/day; n=20) or vehicle (n=20) for 3 wk. Furthermore, we explored the influence of lercanidipine on protein kinase C (PKC) signaling in vivo and in vitro using endothelial and vascular smooth muscle cell cultures. Cumulative mortality was 60% in untreated dTGR, whereas none of the lercanidipine-treated animals died (P<0.001). We found significantly less albuminuria and improved renal function in lercanidipine-treated dTGR (both P<0.05). Lercanidipine treatment also significantly (P<0.05) reduced blood levels of the endogenous NOS inhibitor asymmetric dimethylarginine. On histological examination, we observed significantly less tissue inflammation and fibrosis in lercanidipine-treated animals (both P<0.05). Lercanidipine significantly inhibited angiotensin (ANG) I-mediated PKC-alpha and -delta activation in vivo and in vitro, partly due to reduced intracellular calcium flux. As a result, lercanidipine improved endothelial cell permeability in vitro. Lercanidipine prevents tissue injury and improves survival in a model of progressive organ damage. These effects may result, at least in part, from inhibition of tissue inflammation as well as improved NO bioavailability. Modulation of PKC activity may be an important underlying intracellular mechanism.
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Bloqueadores de los Canales de Calcio/farmacología , Dihidropiridinas/farmacología , Hipertensión/metabolismo , Albúminas/metabolismo , Amidohidrolasas/metabolismo , Angiotensina II/genética , Angiotensina II/metabolismo , Angiotensinógeno/genética , Angiotensinógeno/metabolismo , Animales , Animales Modificados Genéticamente , Arginina/análogos & derivados , Arginina/sangre , Arginina/metabolismo , Regulación Enzimológica de la Expresión Génica , Hipertensión/tratamiento farmacológico , Riñón/efectos de los fármacos , Riñón/metabolismo , Riñón/patología , Ratas , Ratas Sprague-Dawley , Renina/genética , Renina/metabolismoRESUMEN
OBJECTIVE: Angiotensin-converting enzyme inhibitors plus dihydropyridine calcium channel blockers or low-dose thiazide diuretics are considered first-line therapies in hypertensive diabetic patients as glucose metabolism is not relevantly affected. Most diabetic patients require at least two different drug classes to achieve the recommended target blood pressure of 130/85 mmHg. This controlled clinical trial investigated the calcium channel blocker lercanidipine versus hydrochlorothiazide (HCTZ) as add-on in diabetic patients with uncontrolled hypertension on enalapril monotherapy. METHODS: Overall, 174 patients (18-80 years old, well-controlled diabetes type 1 or 2, mild to moderate hypertension) were included in a 2-week placebo run-in followed by 4 weeks on enalapril 20 mg. Subsequently, 135 non-responders (90 mmHg < or = mean sitting diastolic blood pressure < or = 109 mmHg) were randomized to 20 weeks of double-blind add-on therapy to enalapril with either lercanidipine 10 mg (n = 69) or HCTZ 12.5 mg (n = 66). The primary study objective was to prove non-inferiority of lercanidipine add-on versus HCTZ add-on in reducing sitting diastolic blood pressure; response rates and tolerability data were also observed. RESULTS: Both add-on treatments clearly decreased diastolic blood pressure to a greater extent than enalapril monotherapy (mean +/- SD changes at study end: lercanidipine, -9.3 mmHg; HCTZ, -7.4 mmHg); non-inferiority of lercanidipine versus HCTZ was formally proven. Blood pressure response rates reached 69.6% on enalapril plus lercanidipine as compared with 53.6% on enalapril plus HCTZ (difference between treatments, P > 0.05). Blood pressure of 130/85 mmHg or less was achieved in 30.4% of patients on lercanidipine add-on and in 23.2% of those randomized to HCTZ add-on (P > 0.05). Both treatment regimens were well tolerated. CONCLUSION: Lercanidipine add-on showed comparable efficacy to HCTZ add-on in diabetic patients with hypertension badly controlled on angiotensin-converting enzyme inhibitor monotherapy. The blood pressure response rates seemed to be somewhat higher following enalapril plus lercanidipine than enalapril plus HCTZ.
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Antihipertensivos/uso terapéutico , Diabetes Mellitus Tipo 1/fisiopatología , Diabetes Mellitus Tipo 2/fisiopatología , Dihidropiridinas/uso terapéutico , Enalapril/uso terapéutico , Hidroclorotiazida/uso terapéutico , Hipertensión/tratamiento farmacológico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antihipertensivos/efectos adversos , Antihipertensivos/farmacología , Presión Sanguínea/efectos de los fármacos , Presión Sanguínea/fisiología , Bloqueadores de los Canales de Calcio/efectos adversos , Bloqueadores de los Canales de Calcio/farmacología , Bloqueadores de los Canales de Calcio/uso terapéutico , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Dihidropiridinas/efectos adversos , Dihidropiridinas/farmacología , Método Doble Ciego , Quimioterapia Combinada , Enalapril/efectos adversos , Enalapril/farmacología , Femenino , Humanos , Hidroclorotiazida/efectos adversos , Hidroclorotiazida/farmacología , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Método Simple CiegoRESUMEN
The value of plain radiographs, digital subtraction arthrography and radionuclide arthrography was analysed in 23 cases of failed total knee arthroplasty. The preoperative diagnosis was compared with the intraoperative assessment. Sensitivity, specificity and the positive and negative predictive value for assessing a loose component were determined separately for the femoral and tibial components. At revision we found 13 loose femoral and 12 loose tibial implants. In eight cases both components were unstable. Plain radiography had a sensitivity of 77% for loosening of the femoral and 83% for the tibial component; digital subtraction arthrography 77% for the femoral and 8% for the tibial component and radionuclide arthrography 31% and 8%. The specificity for plain radiography was 90% for the femoral and 72% for the tibial implant. For subtraction arthrography it was 50% and 82% and for subtraction arthrography 70% and 82%. Radiography had the highest positive and negative predictive values for both components compared with the other two techniques. As a diagnostic tool to detect implant loosening, plain radiography is the most effective in this study. Subtraction arthrography and radionuclide arthrography are not suitable for use as routine methods for detection of total knee arthroplasty loosening.
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Artrografía/métodos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Análisis de Falla de Equipo/métodos , Inestabilidad de la Articulación/diagnóstico por imagen , Medición de Riesgo/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inestabilidad de la Articulación/etiología , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/cirugía , Masculino , Persona de Mediana Edad , Pronóstico , Falla de Prótesis , Cintigrafía , Reproducibilidad de los Resultados , Factores de Riesgo , Sensibilidad y Especificidad , Técnica de Sustracción , Resultado del TratamientoRESUMEN
OBJECTIVE: To design and evaluate a novel CT-free image-guided surgical navigation system for assisting placement of both acetabular and femoral components in total hip arthroplasty (THA). MATERIALS AND METHODS: The methodology in this paper is conceptually based on our previous work on CT-free cup placement. For femoral component placement, two patient-specific reference coordinate systems are first defined: One for the pelvis, based on the so-called anterior pelvic plane (APP) concept, and one for the femur, using the center of the femoral head, the posterior condylar tangential line, and the medullary canal axis of the proximal femur. A hybrid method is used for the associated landmark acquisition, which involves percutaneous point-based digitization and bi-planar landmark reconstruction using multiple registered fluoroscopy images. The following clinical parameters are computed in real time: cup inclination and anteversion, antetorsion and varus/valgus of the stem, lateralization, and change in leg length for complete THA. In addition, instrument actions such as reaming, impaction, and rasping are visualized for the surgeon by superimposing virtual instrument representations onto the fluoroscopic images. RESULTS: A laboratory study of computer-assisted measurement of antetorsion and varus/valgus, change in leg length, and lateralization for femoral stem placement demonstrated the high precision of the proposed navigation system. Compared with CT-based measurement, mean deviations of 1.0 degrees, 0.6 degrees, 0.7 mm, and 1.7 mm were found for antetorsion, varus/valgus, change in leg length, and lateralization, respectively, with standard deviations of 0.5 degrees, 0.5 degrees, 0.6 mm, and 0.7 mm, respectively. A pilot clinical evaluation showed that THA could benefit from this newly developed CT-free hybrid system. CONCLUSIONS: The proposed CT-free hybrid system promises to increase the accuracy and reliability of THA surgery.