Forest maturity has a stronger influence on the prevalence of spider monkeys than howler monkeys in an anthropogenically impacted rainforest landscape.

The transformation and depletion of primary forest over the past few decades have placed almost half of the world's primate species under the threat of extinction. Developing any successful conservation program for primates requires distribution and demography data, as well as an understanding of the relationships between these factors and their habitat. Between March and June 2010 and 2011 we collected data on the presence and demographic parameters of howler and spider monkeys by carrying out surveys, and validated our findings using local knowledge. We then examined the relationship between forest type and the presence of these primates at 54 sites in the northern area of the Selva Zoque Corridor, Mexico. We detected 86 spider monkey groups across 31 plots and censused 391 individuals (mean ± SD = 5.9 ± 3.0 individuals per sub-group, n = 67 sub-groups). We also detected 69 howler monkey groups across 30 plots and censused 117 individuals (mean ± SD = 5.3 ± 2.4 individuals per group, n = 22 groups). Howler monkey presence was not related to any specific vegetation type, while spider monkeys were present in areas with a higher percentage of tall forest (trees > 25 m high). Overall, spider monkeys were more prevalent than howler monkeys in our sampling sites and showed demographic characteristics similar to those in better protected areas, suggesting that the landscape features in the Uxpanapa Valley are suitable for their needs. Conversely, howler monkey presence was found to be more limited than in other regions, possibly due to the extended presence of spider monkeys.

Effect of patient characteristics on reported outcomes after total knee replacement.

OBJECTIVE: To evaluate the effect of pre-intervention factors in patient-reported outcomes at 6 months post-operatively following total knee replacement. METHODS: A prospective observational study was carried out using two questionnaires sent to patients while they were on the waiting list for surgery: a generic questionnaire, the Medical Outcomes Study Short Form-36 (SF-36), and a specific questionnaire, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Six months after intervention, patients again received the same questionnaires. The dependent variables were the scores of the three domains of the WOMAC and the eight domains of the SF-36. RESULTS: We recruited 640 patients. The mean age was 71 yrs and 73.6% of the patients were females. The multivariate analysis, in which the pre-intervention scores for each domain were added as covariates, showed that the most significant pre-intervention predictors were the baseline scores of each domain. Besides that, the social support, low back pain and the baseline score of the mental health domain (SF-36) were the pre-intervention predictors in the three WOMAC domains. With regard to the SF-36 domains the main predictors were the baseline mental health score, comorbidities, low back pain and social support. CONCLUSIONS: The main predictor of outcome at 6 months post-operatively in all eleven domains was the pre-intervention score of each domain. Presence of social support, absence of low back pain and higher baseline SF-36 mental health score were related to the improvement in the health-related quality of life post-operatively.

Validation of the Spanish version of the WOMAC questionnaire for patients with hip or knee osteoarthritis. Western Ontario and McMaster Universities Osteoarthritis Index.

The aim of this study was to validate a translated version of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire in Spanish patients with hip or knee osteoarthritis (OA). The WOMAC questionnaire and the SF-36 were administered to a sample of 269 patients on the waiting list for hip or knee replacement. We studied the convergent validity and the item-scale correlation using Pearson's correlation coefficient and Spearman's pi. For the reliability study we used another sample of 58 patients who received the WOMAC twice within 15 days. The Pearson's, Spearman's pi, and intraclass correlation coefficients were calculated. Internal consistency was measured by Cronbach's alpha. The responsiveness study was carried out by resending the two questionnaires to all patients 6 months after surgical intervention; responsiveness was measured by means of the paired t-test, the effect size I and the standardised response mean. The Pearson's coefficients for the convergent validity ranged from -0.52 to -0.63. The coefficients obtained for the item-scale correlation of the pain area were 0.74 or higher, 0.91 or higher for stiffness, and 0.61 or higher for function. When measuring the test-retest reliability, the coefficients ranged from 0.66 to 0.81. Internal consistency yielded a Cronbach's alpha ranging from 0.81 to 0.93. The responsiveness showed an effect size I ranging from 1.5 to 2.2 in patients who underwent hip replacement; for those who underwent knee replacement the range was 1 to 1.8. The standardised response mean ranged from 1.3 to 1.9 for patients with hip OA; those with knee OA ranged from 0.8 to 1.5. The Spanish version of WOMAC is a valid, reliable and responsive instrument in patients with hip or knee OA.

Evaluation by explicit criteria of the use of total hip joint replacement.

OBJECTIVE: To evaluate the appropriateness of the use of total hip replacement (THR) using explicit criteria developed by an expert panel. METHODS: Patients with a diagnosis of osteoarthritis who were undergoing THR in five public hospitals in Spain were included consecutively in the study during a 1-yr period. The appropriateness of the indication was judged by explicit criteria developed using a mutidisciplinary approach. Complications were measured 3 months after surgery. One year after discharge, pain, functional limitation and general health were measured. RESULTS: After evaluation of 583 patients, 82 (13.6%) were considered to have undergone inappropriate procedures, and for 279 (46.2%) patients indication for the procedure was considered uncertain. Differences were found in the rate of appropriateness among some centres. One year after discharge, the perception of general health was slightly better in those patients who had been judged to have undergone an appropriate procedure. CONCLUSIONS: The study identified a moderate percentage of inappropriately performed THR. When considered together with those cases that were judged to have uncertain indications, the results indicate that further studies should be done to identify patients who may have an inadequate benefit:risk ratio from this procedure.

Uso apropiado de los mecanismos de fijación en la prótesis de cadera / Appropriateness of fixation mechanism on hip replacement

Objetivo: Evaluar el uso apropiado de los mecanismos de fijación de la prótesis de cadera en pacientes con diagnóstico de osteoartrosis o recambio de prótesis, usando criterios explícitos. Método: Siguiendo el método de uso apropiado de RAND, se realizó una revisión de la bibliografía y se creó una lista de 12 indicaciones para la osteoartrosis y de 32 para los recambios. Un panel de 27 expertos, todos ellos traumatólogos, puntuó el grado de uso apropiado para cada indicación en una escala de 1 (totalmente inapropiado) hasta 9 (totalmente apropiado). Según la mediana de las puntuaciones y el nivel de acuerdo, cada indicación se clasificó como apropiada, dudosa o inapropiada. Posteriormente se recogieron los datos de diez hospitales públicos, de medio y gran tamaño, de la red de Osakidetza-Servicio Vasco de Salud y se aplicaron los criterios desarrollados por el panel de expertos a las intervenciones evaluadas. Resultados: Se evaluaron un total de 831 intervenciones de osteoartrosis y 349 recambios. De las 136 intervenciones en las que se utilizó la prótesis cementada, en dos tercios se consideró apropiada su utilización. La prótesis no cementada se uso más frecuentemente (77 por ciento) y en la mayoría de los casos (94 por ciento) se consideró apropiada de acuerdo a los criterios del panel. De las 68 revisiónes acetabulares en que se emplearon prótesis cementadas, en el 85 por ciento de ellas se recomendaba el uso de un mecanismo no cementado. Sin embargo, de las 134 intervenciones que usaron prótesis no cementadas el panel estaba de acuerdo en un 94 por ciento. Resultados similares ocurrieron con el recambio femoral. Conclusiones: El estudio ofrece unas recomendaciones sobre el uso de las prótesis cementadas y no cementadas basadas en el trabajo de un panel de expertos. Una vez aplicados los criterios del panel se observa un cierto nivel de uso dudoso (AU)

Evaluation of the appropriateness of hip joint replacement techniques.

OBJECTIVE: To evaluate the appropriateness of the use of hip joint replacements (HJRs) using explicit criteria developed by an expert panel. METHODS: Observational study. Nine hundred ninety-seven patients from five hospitals with a diagnosis of osteoarthritis, avascular necrosis, hip fracture, or revision who were undergoing HJR were consecutively included in the study during a 1-year period. The appropriateness of the indication was judged by explicit criteria. Complications were recorded at the time of the intervention and 3 months postoperatively. RESULTS: Of the 1,030 interventions, 604 were for osteoarthritis, 31 avascular necrosis, 191 fractures, and 204 revisions. No differences were found among the hospitals for the main clinical and patient variables. Indications for surgery were considered appropriate in 59% of cases, uncertain in 32%, and inappropriate in 8%, mainly in the osteoarthritis group. Differences were found in the rates of appropriateness among some centers. The complication rate did not differ among the groups based on the level of appropriateness of the procedure. CONCLUSIONS: The appropriate use of HJR, as measured by the criteria established by the panel, identified a moderate percentage of inappropriate indications. Those equivocal and inappropriate cases demand further studies to identify patients with an adequate risk-to-benefit ratio from this procedure.

Evaluation of explicit criteria for total hip joint replacement.

We tested an appropriateness of indications tool for total hip joint replacement in patients with osteoarthritis. Criteria were developed using a modified Delphi panel judgment process. Ratings were analyzed regarding level of agreement among panelists. Another panel rated the same indications; results were compared with the main panel. Test-retest of the main panel was performed. Regression models were used to assess the contribution of each algorithm variable. Appropriateness indication judgment was applied to 84 patients and compared to health-related quality-of-life improvement before and 3 months following intervention. Main panel ratings compared to those of a second panel resulted in a kappa statistic of 0.77. Test-retest kappa for the main panel was 0.81. Patients considered appropriate candidates for surgery, based on their composite indication scores, showed more improvement in health-related quality of life after 3 months than those considered inappropriately by composite indication scores. The previous parameters tested showed acceptable results for an evaluation tool. These results support the use of this indications algorithm as a screening tool for assessing the appropriateness of hip replacement surgery in osteoarthritis.

[Appropriate use of the mechanisms for the fixation of hip prostheses]. / Uso apropiado de los mecanismos de fijación en la prótesis de cadera.

OBJECTIVE: To evaluate the appropriateness of the use of fixation mechanisms for hip replacement in patients with osteoarthritis or prosthesis revision, using explicit criteria. METHODS: Following the RAND appropriateness method, it was carried out a revision of the bibliography and was created a list of 12 indications for osteoarthritis and 32 for the revision. A panel of 27 experts, all of them traumatologists, punctuated the degree of appropriateness for each indication in a scale of 1 (completely inappropriate) up to 9 (completely appropriate). According to the median of the punctuations and the agreement level, each indication was classified as appropriate, uncertain or inappropriate. The data of ten public hospitals of medium and big size of the Basque Service of Health-Osakidetza, were picked up and the developed criteria were applied to the evaluated interventions. RESULTS: 831 osteoarthritis interventions and 349 revisions were evaluated. Of the 136 interventions in which the prosthesis used was cemented, in two thirds its use was considered appropriate. The cementless prosthesis was used more frequently (77%) and in most of the cases (94%) it was considered appropriate according to the criteria of the panel. Of the 68 acetabular revisions in which cemented prosthesis was used, in 85% of them the use of cementless mechanism was recommended. However, of the 134 interventions that used cementless, the panel agreed on 94%. Similar results happened with the femoral revision. CONCLUSIONS: The study offers some recommendations on the use of the cemented and cementless prosthesis, based on the work of a panel of experts. Once applied, the criteria of the panel a certain level of uncertain use is observed.