Evaluation of the Radial Procurvatum Using the Center of Rotation of Angulation Methodology in Chondrodystrophic Dogs

The radial joint orientation angles were calculated using the center of rotation of angulation (CORA) methodology within the frontal and sagittal planes in chondrodystrophic dog breeds, including Welsh Corgi, Dachshund, Pekinese, Poodle, Beagle and Maltese, and it was compared whether there is a statistically significant difference between the breeds. Radial joint orientation angles were obtained in eighty-eight dogs, including 23 Welsh Corgis, 16 Dachshunds, 14 Pekinese, 13 Maltese, 12 Poodles and 10 Beagles. Using the CORA methodology, the cranial proximal radial angle (CrPRA) and caudal distal radial angle (CdDRA) in the sagittal plane and medial proximal radial angle (MPRA) and lateral distal radial angle (LDRA) in the frontal plane were measured for the six breeds studied. The mean values of joint angles for each breed were compared statistically were observed. The CrPRA, CdDRA, and LDRA mean values of Dachshund and Welsh Corgi breeds were significantly smaller than other breeds, and in MPRA, Pekingese showed significantly smaller values than other breeds. This study confirms that the mean values of radial joint orientation angles can be significantly different among chondrodystrophic breeds. To accurately evaluate the degree of angular deformity of the radius, it may be helpful to refer to the average value for each breed with chondrodystrophy.

Correction of Posttraumatic Medial Growth Arrest of the Distal Tibia in Adolescents

Background Partial growth arrest of the medial part of the distal tibial physis following fractures that penetrated the epiphysis is relatively common. We present the results of treatment, based on a protocol of supramalleolar tibial and fibular osteotomy for ankle alignment correction, and contralateral epiphysiodesis of distal tibia and fibula to balance leg length discrepancy (LLD). Methods This case series study describes the results of 7 patients with a median age of 14 years (range = 10-15 years) who were operated in our institution. All were treated by closed or open reduction and internal fixation after Salter-Harris (SH) types 3 and 4 fractures of the distal tibia. All patients had a partial medial growth arrest, distal tibial varus, relative overlengthening of the distal fibula, and slight leg shortening. Treatment Protocol Contralateral distal tibial and fibular epiphysiodesis to prevent significant LLD, completion of closure of the ipsilateral epiphysis, supramalleolar osteotomy of the distal tibia and fibula, and insertion of a triangular wedge cortical allograft into the tibial osteotomy creating a normal ankle joint orientation. The osteotomy was supported by a medial anatomically contoured locking plate. The fibula was fixed with an intramedullary wire. Results All patients had uneventful healing of the osteotomy after 6 weeks. At the latest follow-up (mean 3 years, range 1.5-5 years), 6 out of 7 patients reached maturity, and the lateral distal tibial angle was within normal limits. The LLD in all patients was less than 8 mm. Conclusions Our protocol provides anatomic correction with the restoration of the ankle joint and prevents the progression of LLD. Levels of Evidence: Level IV

Effect of Joint Characteristics and Geometries on Tunnel-Type Anchorage for Suspension Bridge

In this study, the pull-out behavior of a tunnel-type anchorage was examined by considering both geometric and rock joint characteristics. Three-dimensional finite element analyses were performed with reference to the tunnel-type anchorage cases designed and constructed in Korea. The factors influencing the anchorage response were analyzed: the enlarged part, anchorage spacing, joint orientation, spacing, and the shear strength of the rock joints. According to the numerical studies, the size of the enlarged part influenced the failure shape of the tunnel-type anchorage. It was found that the anchorage spacing, the relationship between the tunnel-type anchorage, and the joint orientation and spacing greatly influenced the pull-out behavior of the anchorage. Additionally, the friction angle had a larger impact on the anchorage’s pull-out resistance than the cohesion between the rock joints.

Combined Field and Structure from Motion Survey to Identify Rock Discontinuity Sets of Aa Shallow Rockslide

The present work shows the results of a combined field and Structure from Motion (SfM) survey performed on the detachment surface of a shallow rockslide that occurred in the Rosandra Valley (Trieste, NE Italy), which was aimed at testing the use of 3D models obtained from Remote Sensing (RS) techniques to identify joint sets affecting unstable rock masses. According to discontinuity orientation data acquired from the field (N = 223), the investigated rock mass is affected by at least nine joint sets characterised by a notable variability. The extraction of joint sets from the 3D point cloud representing the surveyed rock outcrop was strongly sensitive to the point cloud density and the values of the controlling parameters of the density function embedded within the discontinuity extractor. This work demonstrates that, in order to properly identify rock joint sets, the exclusive application of a RS approach cannot fully substitute the traditional field survey, and the estimation of discontinuity sets should be integrated with joint orientation data acquired using a geological compass. To maximise its capabilities, the semi-automatic discontinuity set extraction from 3D point clouds should always be supported by a significant statistical sample of joint orientation measurements that are preliminarily collected from the field.

The PRECICE nail system: The initial Kuwaiti experience

Objectives: The PRECICE system is an implantable limb lengthening intramedullary nail with remotely magnetically controlled distractors indicated for limb length discrepancy (LLD) and short stature treatment. This study reports the initial experience of the Kuwaiti deformity correction unit in utilizing the PRECICE system. Methods: Ten patients (four females and six males) were included in this study. All cases were operated using the PRECICE nail system (five antegrade femoral nails, three retrograde femoral nails, and two tibial nails). All surgeries were performed during January 2019 to February 2020. Results: The mean age of participants was 20 years (12–33 years), with a 21.6 kg/m2 mean body mass index (17–28). LLD etiologies (mean LLD = 39 mm) were congenital (n = 2), developmental (n = 2), post-traumatic non-union (n = 1), post-traumatic malunion (n = 1), post-traumatic physeal arrest (n = 1), and post-deformity correction and lengthening of the contralateral side with circular frame (n = 3). The mean distraction rate was 0.97 mm/day (range: 0.75–1.2 mm/day). Mean lengthening was 39 mm (range: 20–60 mm). Healing was confirmed at 76 days on average (range: 50–120 days). All patients reached full consolidation to regenerate bone, normal alignment, and normal joint orientation. Antegrade femur lengthening was done in five patients. One patient with a previous knee fixed flexion deformity of 25° improved to a 5° lag of extension. No complications were observed during the lengthening procedures. All the patients were followed up for a minimum of 12 months. Conclusion: The PRECICE nail system was successful in lengthening cases with different etiologies, achieving target lengths without complications. All the patients had reported excellent functional outcomes.

DESIGN ASPECTS OF INSTALLATION DEVICES OF THE SUPPORT RINGS

The processes of manufacturing machines and appliances show a continuous tendency to increase the degree of automation. An important role in the automation of manufacturing processes is played by the constructive technologicality of the product. It is important to use a minimum number of components, which have a construction as technological as possible in terms of automation. In this context, the use of supporting rings as fasteners is welcome. The design of the installation devices of these rings requires the knowledge of their deformation forces, information that is missing in the profile literature. The authors set their goal to develop the method for calculating the forces required to deform the supporting rings with a rectangular transverse profile and their maximum allowable deformations. The calculation relationships were obtained by formalizing the supporting ring through a bar with a fixed end and studying its deformation using Mohr's integral. The article lists some types of the supporting rings used in the construction of machines and appliances, their advantages and disadvantages, aspects of their automatic installation: deformation and installation methods, precision of joint orientation, optimal design, calculation of forces required for deformation and the maximum permissible deformation value. As a result of the research carried out, recommendations were developed regarding the calculation of some constructive parameters of the devices for installing the supporting rings.

Deformity analysis of the lower limb on the coronal plane in patients with rheumatoid arthritis and osteoarthritis

ABSTRACT Objectives To evaluate joint orientation angles of the coronal plane in patients with rheumatoid arthritis (RA) in comparison with osteoarthritis (OA). Methods In total, 72 patients with RA (90 knees) and 76 patients with OA (90 knees) who underwent total knee arthroplasty were enrolled. The hip–knee–ankle (HKA) angle, mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA), and joint line convergence angle (JLCA) were measured on preoperative long-leg radiographs in the standing position. Student’s t-test was used to assess differences in radiographic data between patients with RA and OA. Results In knees with RA and OA, the mean HKA was −3.4 ± 9.4° and −10.6 ± 8.0°, the mean mLDFA was 86.6 ± 3.7° and 88.2 ± 2.7°, the mean mMPTA was 85.9 ± 4.0° and 84.3 ± 3.7°, and the mean JLCA was 2.7 ± 4.2° and 6.8 ± 4.1°. All parameters in the knees with RA were more valgus than those with OA. Conclusions Knees with RA had a great variability in joint orientation angles on the coronal plane; the whole lower limb alignment and the femur, tibia, and joint were more valgus in knees with RA than with OA.

Analysis of the influence of joint direction on production optimization in enhanced geothermal systems

Heat extraction from geothermal reservoir by circulating cold water into a hot rock requires an amount of fluid pressure, which is capable of inducing fault opening. Although stress change promotes the potential of fault failure and reactivation, the rate at which fluid pressurization within the fault zone generates variations in pore pressure as fault geometry changes during geothermal energy production have not been thoroughly addressed to include the effects of joint orientation. This study examines how different fault/joint models result in different tendency of injection-induced shear failure, and how this could influence the production rate. Here, a numerical simulation method is adopted to investigate the thermo-hydro-mechanical (THM) response of the various fault/joint models during production in a geothermal reservoir. The results indicate that pore pressure evolution has a direct relationship with the evolution of production rate for the three joint models examined, and the stress sensitivity of the individual fault/joint model also produced an effect on the production rate. Changing the position of the injection well revealed that the magnitude of shear failure on the fault plane could be controlled by the hydraulic diffusivity of fluid pressure, and the production rate is also influenced by the magnitude of stress change at the injection and production wells. Overall, the location of the injection well along with the fault damage zone significantly influenced the resulting production rate, but a more dominating factor is the joint orientation with respect to the maximum principal stress direction. Thus, the rate of thermal drawdown is affected by pore pressure elevation and stress change while the fault permeability and the production rate are enhanced when the joint’s frictional resistance is low.

Skeletal Manifestations of Heritable Disproportionate Dwarfism in Cats as Determined by Radiography and Magnetic Resonance Imaging

Objective The aim of this study was to characterize the radiographic alignment of thoracic and pelvic limbs and evaluate for intervertebral disc disease in cats with feline disproportionate dwarfism (FDD). Study Design Observational cross-sectional study. Radiographic joint orientation angles were measured in 10 thoracic and pelvic limbs from 5 FDD cats and compared with those angles measured in 24 thoracic limbs and 100 pelvic limbs from skeletally normal cats. Magnetic resonance imaging of the spine was performed in 2 FDD cats for the evaluation of pathology of the intervertebral discs or vertebrae. Results All limbs from FDD cats possessed deformities. FDD humeri demonstrated procurvatum proximally, and recurvatum distally in the sagittal plane, but showed no difference in the frontal plane. FDD radii possessed excessive recurvatum proximally, and procurvatum distally in the sagittal plane, and varus proximally and valgus distally in the frontal plane. Whereas no torsion was discernible in the humeri, all radii had external torsion. In the frontal plane, FDD femurs exhibited varus both proximally and distally whereas the tibia possessed proximal valgus and distal varus. No torsion in the pelvic limbs was observed. No spinal pathology was detected in the FDD cats included in the original study. Conclusion Feline disproportionate dwarfism results in significant appendicular deformity in all limbs. The incidence of intervertebral disc degeneration in FDD cats is inconclusive.