Banchong Mahaisavariya

Spinal accessory neurotization for restoration of elbow flexion in avulsion injuries of the brachial plexus

Traumatic root avulsion brachial plexus injuries in 216 patients were treated with spinal accessory-musculocutaneous neurotization to restore elbow flexion. The average postoperative follow-up period was 6 years, with a minimum of 2 years for all patients. The percentage of satisfactory biceps recovery (MRC III or better) was 72.5%. The average interval between the operation and MRC III motor recovery was 17 months. The percentage of poor results increased from 25.5% to 62.5% in patients who underwent operation later than 9 months after injury. This method of neurotization produces a result comparable with, if not better than, the results of other types of neurotization in restoration of elbow flexion.

Morphological study of the proximal femur: a new method of geometrical assessment using 3-dimensional reverse engineering

This study presents a new method of using computerized tomography images combined with the reverse engineering technique to obtain and analyse the three-dimensional inner and outer geometry of the proximal cadaveric femur. Three-dimensional models were reconstructed from the computerized tomography images and approximated with 2D and 3D fitting algorithms based on reverse engineering methods. The following parameters were calculated for each femur: femoral head diameter, femoral neck axis, femoral shaft axis, anteversion angle and neck-shaft angle. These data represent the geometry of the studied proximal femur, and can be used for the design of proper size and shape of femoral prostheses and trochanteric nail systems.

Neglected dislocation of the elbow.

We retrospectively review the intermediate-term to long-term results of 24 patients treated after late open reduction of neglected posterior elbow dislocation in terms of the elbow, particularly noting joint mobility. The mean interval from injury to operation was 7.9 months (range, 1–60 months). The posterior approach with V-Y muscleplasty was used in most patients with 2 to 3 weeks postoperative immobilization. The average preoperative arc of elbow flexion was from 17° with an average maximum flexion of 27° (range, 5–60°) and an average flexion contracture of 10° (range, 0–30°). The mean followup was 48.3 months (range, 12–132 months). At the time of final followup, the average arc of elbow flexion was 82° with an average of maximum flexion of 122° (range, 90–150°) and an average flexion contracture of 40° (range, 0–75°). There was no correlation between the postoperative arc of elbow motion and preoperative parameters including patient age, preoperative arc of elbow motion, or duration of untreated dislocation.

Morphology of the radial head: A reverse engineering based evaluation using three-dimensional anatomical data of radial bone:

Abstract The proximal part of the radius has a complex shape and dimension that cannot be precisely determined by standard roentgenogram for real three-dimensional anatomical shape which is important for prosthesis design. This study presents a method by which computer tomography (CT) images are combined with the reverse engineering technique to obtain and analyse the three-dimensional inner and outer geometry of the proximal radius. The three-dimensional models were reconstructed from CT images obtained from 40 radial bones and approximated with two- and three-dimensional fitting algorithms based on reverse engineering methods. The mean total length of the radius was 240.0mm [standard deviation (SD) = 17.3]. The radial head in this study is more likely to be circular with an average diameter of 20.5 mm (SD = 1.9). The outer diameter of the radial neck averages 14.7 mm (SD = 1.0). The thickness of the radial head averages 12.9 mm (SD = 1.4). The intramedullary canal diameter of the radial neck averages 7.4 mm (SD = 1.4). The depth of the fossa at the articular surface averages 1.5 mm (SD = 0.4).

Osteotomy for cubitus varus A simple technique in 10 children

10 children with cubitus varus deformity after supracondylar fractures were operated on with a supracondylar lateral closing wedge osteotomy. The medial cortical periosteal hinge was left intact and the osteotomy stabilized with two Kirschner wires and a tension-band wire loop. The osteotomies healed within 2 months, without any complications or recurrence of the deformity. The outcome was satisfactory as regards both cosmesis and mobility.

Bending and branching of anodic aluminum oxide nanochannels and their applications

During fabrication of anodic aluminum oxide (AAO) membranes, it is observed that sometimes their nanochannels experience bending and branching. In this research the bending and branching behavior of AAO nanochannels was studied. AAO nanochannels were fabricated in 99.56% pure aluminum (Al) in which Si and Fe impurities blocked the propagation of some nanochannels. It was observed that the neighboring channels bend and make branches for anodizing the Al beneath impurities. The authors developed a model that explains the bending and branching of AAO nanochannels. Our experiments show that AAO nanochannel can bend and divide into branches if it experiences nonanodized Al on one side of the nanochannel. Bending and branching effects were also observed when AAO was fabricated using Al with nonplanar surfaces. The authors found that the bending and branching behavior of AAO nanochannels minimizes impurity defects in the AAO membrane. Based on experimental results, a model has been developed for making 3D struct...

Isolated Articular Melioidosis

Melioidosis is an infection caused by a gram-negative bacilli, Pseudomonas pseudomallei. This organism can cause fatal infection in domestic animals and are probably transmitted to humans by soil contamination of skin abrasions, ingestion, and inhalation. Melioidosis is being increasingly diagnosed in Western countries in other than its endemic areas of tropical and subtropical zones. In the past, only a few single case reports of articular melioidosis were published in English journals, and almost all were secondary to melioidosis of another organ. Accurate diagnosis of this infection is important because a high mortality rate is usually associated with the septicemic form. Nine cases of isolated articular involvement were diagnosed between 1984 and 1988 in Northeast Thailand. Symptoms were subtle and diagnosis required a high degree of suspicion. Diagnosis depended on bacteriologic methods including Grams stain, pus and blood cultures, and on an indirect hemagglutination titer of over 1:40. In addition to general measures for septic arthritis, antibiotic therapy using a combination of intravenous cotrimoxazole, doxycycline, and chloramphenicol was generally satisfactory. Second line drugs (i.e., more effective but also more expensive drugs that the authors administered when patients failed to respond to the first line drugs cotrimoxazole, doxycycline, and chloramphenicol) comprising intravenous ceftazidime and cotrimoxazole were administered in cases with an underlying disease. Comparison of the disease course before and during hospitalization as well as the total days of treatment between two small groups of patients with and without underlying disease revealed no statistically significant difference.

Musculoskeletal Trauma Service in Thailand

Trauma is becoming a leading cause of death in most of the low-income and middle-income countries worldwide. The growing number of motor vehicles far surpasses the development and upkeep of the road and highway networks, traffic laws, and driver training and licensing. In Thailand, road traffic injuries have become the second leading cause of death and morbidity overall since 1990. The lack of improvement to existing roadways, implementation of traffic safety and ridership laws including seatbelt regulations, and poor emergency medical assistance support systems all contribute to these statistics. An insufficient number and inequitable distribution of healthcare professionals is also a national problem, especially at the district level. Prehospital care of trauma patients remains insufficient and improvements at the national level are suggested.

Novel anodic aluminum oxide (AAO) nanoporous membrane for wearable hemodialysis device

In this paper a novel structure of AAO membrane is reported. The AAO membrane was fabricated from commercial grade impure aluminum sheet. The fabricated membrane has hexagonal structure and the nanopores appeared at the bottom of that honeycomb structure. The thickness of fabricated membrane is 42.5µm. The average diameter of upper layer pore is 350nm and average diameter of lower layer pore is 50nm. The nanopores inside the fabricated membrane are highly straight and perpendicular to the surface. This two layer AAO membrane will speed up the hemodialysis process.

Multifield Analysis Using Multiple Code Coupling of a MEMS Based Micropump with Biocompatible Membrane Materials for Biomedical Applications

We present multifield analysis of a MEMS based piezoelectrically actuated valveless micropump with biocompatible polymer membrane materials for drug delivery applications. A three dimensional model of the micropump is built and fluid-structure interface effects have been taken into account infinite element analysis using multifield code coupling method. The dependency of the micropump characteristics on micropump dimensions and membrane and actuator materials is investigated. The analysis predicts that there is a definite relationship between membrane and piezoelectric layer thickness to obtain maximum pump flow. Diffuser geometrical dimensions such as diffuser length, diffuser neck width and diffuser angle play a critical to enhance the performance of the micropump and need to be optimized before fabrication.