Pararectus Approach in Acetabular Fractures in Patients Older Than 65 years. Is it Possible to Improve the Technique?

OBJECTIVES: Review clinical results of the treatment for acetabular fractures using the pararectus approach and analyze surgical variations of the traditional approach. DESIGN: Retrospective. SETTING: Tertiary referral hospital. PATIENTS: 46 patients over 65 years of age who sustained an acetabular fracture and underwent surgery using the pararectus approach. INTERVENTION: Fractures were treated using a pararectus approach. Three variations of the original technique were performed: (1) Ligature of the deep iliac circumflex artery and vein, (2) separation of the psoas and iliacus muscles, and (3) isolation of the spermatic cord in men and round ligament in women together with the iliac and epigastric vessels. MAIN OUTCOME MEASUREMENTS: Outcomes measures included surgical, demographic, and clinical data, and information related to follow-up. RESULTS: Duration of surgery, 125 minutes (95-210). Quality of reduction on postoperative computed tomography (CT) scan; anatomic in 22 patients (47.8%), incomplete in 16 (34.8%), and poor in 8 (17.4%). In patients in whom the hip was preserved (n = 41), functional status was excellent in 15 patients (36.5%), good in 17 (41.4%), fair in 6 (14.7%), and poor in 3 (7.4%), with mean functional score of 16 points (7-18). Seven patients (15.2%) developed posttraumatic osteoarthritis and 4 of these patients underwent total hip replacement. CONCLUSIONS: This study reports positive outcomes in fracture reduction and clinical outcomes with low complications in older patients who suffered acetabular fractures and were treated using a pararectus approach. Small variations in the technique, such as those proposed in this study, may help to widen access to the surgical site and simplify the technique. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Comparison of methods for assigning the material properties of the distraction callus in computational models.

In silico models of distraction osteogenesis and fracture healing usually assume constant mechanical properties for the new bone tissue generated. In addition, these models do not always account for the porosity of the woven bone and its evolution. In this study, finite element analyses based on computed tomography (CT) are used to predict the stiffness of the callus until 69 weeks after surgery using 15 CT images obtained at different stages of an experiment on bone transport, technique in which distraction osteogenesis is used to correct bone defects. Three different approaches were used to assign the mechanical properties to the new bone tissue. First, constant mechanical properties of the hard callus tissue and no porosity were assumed. Nevertheless, this approach did not show good correlations. Second, random variations in the elastic modulus and porosity of the woven bone were taken from previous experimental studies. Finally, the elastic properties of each element were assigned depending on gray scale in CT images. The numerically predicted callus stiffness was compared with previous in vivo measurements. It was concluded firstly that assignment depending on gray scale is the method that provides the best results and secondly that the method that considers a random distribution of porosity and elastic modulus of the callus is also suitable to predict the callus stiffness from 15 weeks after surgery. This finding provides a method for assigning the material properties of the distraction callus, which does not require CT images and may contribute to improve current in silico models.

Histological study of the docking site after bone transport. Temporal evolution in a sheep model.

INTRODUCTION: Bone transport appears to be a solution for segmental bone defects; specifically, the "docking site" is where the transported segment meets the target segment at the end of the process. A lack of its consolidation is one of the major causes of failure for this technique. Many studies have been performed in order to enhance the consolidation of the docking site, but histological changes occurring in it remain unknown. The aim of this study was to determine microscopic changes present in this area, from distraction to remodeling, in order to clarify the best options to facilitate the success of this technique. MATERIALS AND METHODS: Ten adult sheep were submitted to bone transport using an Ilizarov external fixator. Histomorphometry and immunohistochemical studies were performed in the docking site to determine the main types of ossification, the evolutions of tissues and blood vessels and the distributions of collagen I and II. RESULTS: Ossification was mainly intramembranous with some areas of endochondral ossification. Fibrous tissue was predominant until 98 days after surgery. The area occupied by blood vessels increased until 50 days after surgery, when it decreased slowly until the end of the study. CONCLUSIONS: As far as the authors know, this is the first histological study performed in the docking site reporting the complete evolution of tissues until the end of remodeling, showing results contrary to those published by others authors. This could help to clarify information about its union and may be useful for future investigations about techniques for improving the consolidation of the docking site in humans.

Factores determinantes en la indicación de la prótesis invertida de hombro / Facteurs déterminant l'indication de prothèse d'épaule inversée / Determining Factors in Inverted Shoulder Prosthesis Indication

Objetivo: Desarrollar criterios para determinar las indicaciones apropiadas de la prótesis invertida de hombro en artropatías por lesión del manguito rotador y las variables determinantes de este proceso. Método: Se utilizó un panel de expertos mediante metodología RAND/UCLA con 9 expertos en Traumatología, 2 en Rehabilitación y 1 en Reumatología, que evaluaron 192 casos hipotéticos. Cada experto puntuó mediante una escala del 1 (extremadamente inadecuado) al 9 (extremadamente apropiado). Resultados: 22 casos hipotéticos fueron considerados adecuados. El dolor, limitación funcional, necesidad funcional, defecto glenoideo, edad, artrosis y posibilidad de reparación del manguito rotador son variables determinantes para indicar la implantación de una prótesis invertida de hombro. Conclusiones: El método RAND/UCLA es útil para el estudio de las indicaciones de procedimientos como la prótesis invertida de hombro, y proporciona una lista de las indicaciones adecuadas. Las variables requieren ser validadas mediante estudios prospectivos o revisión de historias clínicas(AU)

Objective: Develop criteria to determine the appropriate indications of inverted shoulder prosthesis in arthropathies due to rotator cuff injury and the variables that determine this process. Method: A panel of experts assessed 192 hypothetical cases using RAND/UCLA methodology. Nine Traumatology experts, two Rehabilitation experts and one Rheumatology expert comprised this panel. Each expert scored on a scale from 1 (extremely unsuitable) to 9 (extremely appropriate). Results: 22 hypothetical cases were considered adequate. Pain, functional limitation, functional need, glenoid defect, age, osteoarthritis and possibility of rotator cuff repair are determining as variables to indicate the implantation of an inverted shoulder prosthesis. Conclusions: The RAND/UCLA method is useful for the study of procedure indications such as the inverted shoulder prosthesis, and it provides a list of suitable indications. Prospective studies or medical record reviews should validate these variables(AU)

Objectif: Proposer les critères définissant l'indication appropriée de prothèse d'épaule inversée dans les arthropathies pour lésion de la coiffe des rotateurs, et les variables déterminant ce processus. Méthodes: Un panel d'experts, compris par 9 traumatologues, 2 kinésithérapeutes et 1 rhumatologue, a été utilisé pour évaluer 192 cas hypothétiques par la méthode RAND/UCLA. Chaque expert a fait son évaluation sur une échelle de 1 (extrêmement inapproprié) à 9 (extrêmement approprié). Résultats: Vingt-deux cas hypothétiques ont été considérés comme appropriés. Des variables telles que la douleur, la limitation fonctionnelle, la nécessité fonctionnelle, le défaut glénoïdien, l'âge, l'arthrose et la possibilité de correction de la coiffe des rotateurs, ont déterminé l'indication de prothèse d'épaule inversée. Conclusions: La méthode RAND-UCLA est utile pour l'étude des indications de procédés, tels que la prothèse d'épaule inversée, et procure une liste des indications appropriées. Il faut valider les variables avec des études prospectives ou une révision des dossiers médicaux(AU)

Bone health, daily physical activity, and exercise tolerance in patients with cystic fibrosis.

BACKGROUND: Daily physical activity (PA) may be an excellent tool for the maintenance of bone health in patients with cystic fibrosis (CF). The aim of this study was to analyze the possible association between physical capacity and activity and bone mineral density (BMD) in young adults with CF. A secondary goal was to evaluate vertebral fractures in this population. METHODS: A cross-sectional study was conducted in 50 patients with CF who were clinically stable and aged > 16 years but not lung transplant recipients. PA was quantified with a portable motion monitor (BodyMedia Fit Armband). Cardiopulmonary exercise and 6-min walk tests were used to assess exercise capacity. BMD was obtained from dual-energy x-ray absorptiometry of the lumbar column, hip, and whole body. To analyze vertebral fractures and deformity, we performed the Genant and Cobb methods. RESULTS: Daily PA time at low (3-4.8 metabolic equivalent tasks [METs]) and moderate (4.8-7.2 METs) intensity, respectively, was correlated with Z score (BMD) of the lumbar column (r = 0.36, P < .01 and r = 0.59, P < .001), the neck of femur (r = 0.51, P < .001 and r = 0.72, P < .001), and the total hip (r = 0.54, P < .001 and r = 0.74, P < .001). PA, BMI, age, and sex were predictors of BMD. Vertebral fractures correlated with kyphosis (r = 0.42, P = .02), but not with BMD. Patients who were mildly and severely affected differed in vertebral fracture rate and kyphosis prevalence (P = .002 and P = .013, respectively). CONCLUSIONS: The most active patients with better exercise capacity had higher BMD. Those with more affected pulmonary function had a greater prevalence of vertebral fractures and dorsal kyphosis.