Objectivation of an Educational Model in Cranial Osteopathy Based on Experience.

Background and Objectives: The techniques directed to the cranial field in osteopathy are the most questioned due to the lack of scientific evidence. In osteopathic practice, manual palpation is essential and, therefore, measuring reliability is fundamental. The objective of this study is to assess the precision and objectification of an educational model in cranial osteopathy based on experience. Materials and Methods: A reliability study was conducted in a cadaver skull where a strain gauge was placed on the sphenobasilar synchondrosis (SBS) of the base of the skull. Three cranial osteopathic techniques (lateral compression, anteroposterior compression, and compression maneuver of the mastoids) were performed 25 times by osteopaths with different degrees of experience (5-10 years, 1-5 years, <1 year). Measurements were computed for each of the three techniques of each group in comparison with the osteopath with >15 years of experience. Data were analyzed to check for inter- and intra-observer reliability using intra-class correlation coefficients (ICC). Results: Reliability in osteopaths with 5-10 years' experience (observer 1 and observer 2) performing all three techniques was higher (p < 0.001) than the osteopath with >15 years' experience. Little or no reliability were observed in osteopaths with less experience. Conclusions: The experience of the osteopaths determines the reliability and effectiveness of the cranial techniques, a fundamental part in objectifying these techniques. This model can help implement objective training in cranial osteopathy formation.

Biomechanical features of six design of the delta external fixator for treating Pilon fracture: a finite element study.

Pilon fractures can be caused by high-energy vertical forces which may result in long-term patient immobilization. Many experts in orthopedic surgery recommend the use of a Delta external fixator for type III Pilon fracture treatment. This device can promote immediate healing of fractured bone, minimizing the rate of complications as well as allowing early mobilization. The characteristics of different types of the Delta frame have not been demonstrated yet. By using the finite element method, this study was conducted to determine the biomechanical characteristics of six different configurations (Model 1 until Model 6). CT images from the lower limb of a healthy human were used to reconstruct three-dimensional models of foot and ankle bones. All bones were assigned with isotropic material properties and the cartilages were assigned to exhibit hyperelasticity. A linear link was used to simulate 37 ligaments at the ankle joint. Axial loads of 70 and 350 N were applied at the proximal tibia to simulate the stance and swing phase. The metatarsals and calcaneus were fixed distally in order to prevent rigid body motion. A synthetic ankle bone was used to validate the finite element model. The simulated results showed that Delta3 produced the highest relative micromovement (0.09 mm, 7 µm) during the stance and swing phase, respectively. The highest equivalent von Mises stress was found at the calcaneus pin of the Delta4 (423.2 MPa) as compared to others. In conclusion, Delta1 external fixator was the most favorable option for type III Pilon fracture treatment. Graphical abstract ᅟ.

Best estimation of spectrum profiles for diagnosing femoral prostheses loosening.

For the past few years, some authors have proposed several vibration analysis techniques to detect the prosthetic femoral stem loosening, having found some differences in the frequency response between secure and loose stems. Classical methods like periodogram have been used in most studies for the spectral estimation, and their conclusions have been reached only by visual inspection. A new metric called Non-linear Logarithmic Weighted Distance (NLWD), based on log-spectral distance is presented. As its name suggests, the spectral power is weighted in order to highlight discriminatory patterns of the spectral profiles. A Generalized Discriminant Ratio (GDR) based on NLWD metric has been also defined. In this study, experiments on a cadaveric dried bone with two kinds of fixation, Loose Stem class (LS) and Secure Stem class (SS), have been analyzed. To select the most discriminating approach to spectral estimation, five well known algorithms (Welch's, Burg's Auto-Regressive (AR), Auto-Regressive Moving Average (ARMA), Multiple Signal Classification (MUSIC) and Thomson's Multi-taper (MTM)) have been compared by using GDR. Finally, the use of the MTM method is proposed for the analysis of bone-stem interface vibratory signals, since it yields the most discriminatory profiles.