We present a wavefront reversal technique to produce a dual-field fringe pattern for self-referencing collimation testing in wedge-plate lateral-shear interferometry. The method requires only a suitably placed cubic beam splitter to produce two replicas of the fringe field formed by the wedge-plate lateral-shear interferometer. One of the replicas has a fringe pattern that is the reverse of the other. With these two fringe fields, the collimation testing has a built-in reference, and the detection sensitivity is twice that of a single-wedge-plate technique.
The application of concrete filled steel tubes(CFSTs) as composite members has widely been used around the world and is becoming popular day by day for structural application especially in earthquake regions. This paper indicates that an experimental study was conducted to comprehend the behaviour of T-stub end plates connected to concrete filled thin-walled steel tube (CFTST) with different types of bolts and are subjected to pullout load. The bolts used are normal type bolt M20 grade 8.8 and Lindapter Hollo-bolt HB16 and HB20. A series of 10 mm thick T-stub end plates were fastened to 2 mm CFTST of 200 mm x 200 mm in cross-section. All of the specimens were subjected to monotonic pull-out load until failure. Based on testresults, the Lidapter Hollo-boltsshowed better performance compare to normal bolts. The highest ultimate limit load for T-stub end plate fasten with Lindapter Hollo-bolt is four times higher than with normal bolt although all end plates show similar behaviour and failure mode patterns. It can be concluded that T-stub end plate with Lindapter Hollo-bolt shows a better performance in the service limit and ultimate limit states according to the regulations in the design codes.
Three types of binder PVA, PVC and PVA/PVC mixtures have been evaluated for PANi-TiO2 immobilized system. These binders have been varied to several weights of loading for optimization purposes. As a result, it shows that higher loading of binders improved the photodegradation of RR4 dye but the mechanical properties of each immobilized system started to decreases. This behavior occurs due to the immobilized particles coated on the plate easy to peel off despite weak attachment toward to the continuous photodegradation operation system. Therefore 4 times of dipping PVA and PVC layers was selected as the optimum loading of binders to the PANi/TiO2 system during photocatalytic degradation of Reactive Red 4 with the rate constant of 0.5568 K/min for PVA and 0.5742 K/min for PVC. Meanwhile for PVA/PVC mixture binder system at 4 times dipping showed the highest rate constant of photodegradation of RR4 dye with 0.6026 K/min. In addition, SEM analysis has also been carried out for further investigation.
This study aims at investigating the mechanical properties of the contemporary metallic bone plates determining the effect of their length, width and thickness on the properties and compares with the composite bone plates. Three-points bending test was performed over the stainless steel plates of different length, width and thickness. The test results showed that different plates had different mechanical properties. However, the properties are still much higher than that of particular bones intended to be treated. Therefore, the reported findings strongly encourage developing composite bone plates with biocompatible polymers/fibers that would have modulated properties according to the requirements.
The diaphyseal tibia fracture is best treated with intramedullary nail but in some cases where the nail is not applicable, plate fixation will be the next option of fixation. The extensile anterior approach is normally used for conventional compression plate fixation in tibia shaft fractures. The extensive surgical dissection may devitalizes the bony fragments and interfere with the fracture union as well as soft tissue healing. Minimally Invasive Plate Osteosynthesis (MIPO) provides good preservation of blood supply and fracture hematoma at the fracture site thus promotes biological bone healing. The use of indirect reduction techniques and small skin incisions to introduce the plate is technically demanding and requires fluoroscopy exposures throughout the surgery, being some of its drawbacks. We recommend MIPO for conventional compression plate fixation in tibial shaft fractures in view of the reduced surgical trauma to the surrounding soft tissue and good functional outcome.
Hoffa fractures are rare and difficult fractures to manage. Hoffa fracture involves a coronal plane fracture of posterior femoral condyle. Non-union in Hoffa fracture is further difficult to manage. The surgical management for such nonunion includes open reduction with recon/LCP plate or screw fixation with bone grafting. The problem with plates is the difficulty in contouring the plates according to the shape of posterior femoral condyles. We describe a new technique with 2 L shaped neutralisation plates placed in a circular fashion. This technique provides a more rigid construct and gives better holding strength of screws in Hoffa fragment. This enhances union and mobilisation can be started early.
Irreducible closed dorsal dislocation of distal interphalangeal (DIP) joint of the finger is a rare injury. The causes of irreducibility of the DIP joint are volar plate interposition, entrapment of flexor digitorum profundus tendon behind the head of middle phalanx, and buttonholing of the middle phalanx head through the volar plate or flexor tendon. Open reduction with a volar approach is recommended with the advantages of better wound healing, ease of releasing entrapped structures, and possibilities of a volar plate, collateral ligaments, and/or flexor tendon repair. We report a case of irreducible dorsal dislocation of left ring finger DIP joint secondary to volar plate interposition treated successfully with open reduction.
Removal of plates is a procedure commonly performed by orthopaedic surgeons and stripped screws are probably the most common problem encountered during this procedure. Stripped screws are caused by slippage between the screwdriver and the screw. Due to the inherent difficulty in removing such screws, surgeons should be knowledgeable in techniques for their removal and should be equipped with the proper instruments to expedite the procedure. There are few published articles about such techniques. This report describes a technique for removal of plates with stripped screws. The tip of a stripped screw is approached from the far cortex and then reamed with a trephine reamer in the direction of the screw until both cortices are cleared. The plate is then removed with stripped screws attached. All the removals utilizing this technique to date have been successful with no complications, and this method is safe, efficient and technically easy to learn.
We conducted a retrospective review on eleven patients who were treated for Type A and C distal femoral fractures (based on AO classification) between January 2004 and December 2004. All fractures were fixed with titanium distal femoral locking compression plate. The patient’s ages ranged from 15 to 85 with a mean of 44. Clinical assessment was conducted at least 6 months post-operatively using the Schatzker scoring system. Results showed that four patients had excellent results, four good, two fair and one failure.
Open reduction and internal fixation using
conventional lateral distal femur locking plate is a
standard operative method for distal femur fracture.
This case series describes medial plating of distal
femur fracture using proximal tibia locking plate that
is anatomically fit to the medial aspect of distal femur,
by the minimally invasive plate osteosynthesis (MIPO)
technique which gives a stable construct with good
outcome.
In this paper, an extensive work on the natural frequency of perforated plate has
been made by introducing micro-holes on the plate. The micro-holes, which is known
to have a remarkable performance in several applications, were arranged diagonally
among the perforated holes in order to make a new combination of micro-macro
perforated plate. A 3D geometrical model of the plate was made in the Autodesk
Inventor and the Finite Element (FE) simulation was employed to calculate the
natural frequency and visualize the mode shape. Four models were made with
various micro-holes diameter starting from 0,25, 0,5, 0,75 and 0,9 mm, respectively.
The macro holes diameter, however, was kept constant to be 1,5 mm purposely to
know the effect of micro holes in particular. The results from the models were then
compared to a single perforated plate (PP) for clarification. It is found that the micro
holes gives considerable effect to the perforated plate natural frequency. Similar to
the author previous findings, the diameter of the micro holes is proportional to the
natural frequency reduction.
Peri-implant fractures distal to an antegrade femoral nail are uncommon injuries, with no current consensus on the best treatment modality. We are presenting three cases of periimplant fractures distal to an antegrade femoral nail. All patients sustained an initial traumatic injury, which was managed with an antegrade femoral nail fixation. They subsequently suffer a second injury which causes periimplant fracture. Our first two patients were managed with removing the intramedullary nail followed by Less Invasive Stabilization System (LISS) plate fixation. In our third case, the intramedullary nail was left in-situ, and the fracture was fixed with a polyaxial locking plate We discuss their injury pattern, investigations and surgical management. Polyaxial locking plates show great promise in this setting as they allow fixation of the fracture whilst maintaining the existing nail to protect the entire femur from further injury.
Patellar fracture after total knee replacement (TKR) is one of the challenging problems in periprosthetic fracture. Open reduction with internal fixation (ORIF), as tension band wiring (TBW), usually required in cases with extensor mechanism disruption. However, many studies reported a high failure rate after using this technique. In this report, we presented an interesting case of periprosthetic patellar fracture after TKR with TBW failure that was successfully treated with double non-locking reconstruction plates fixation and TBW augmentation.
This study aimed to investigate the effects of element diffusion on the alloying behaviour and microstructure of a Ti-10%Mo10%Cr
alloy during sintering and furnace cooling. A theoretical calculation of the average diffusion distance for each
element was performed to predict the alloying behaviour during sintering and furnace cooling. The Ti-10%Mo-10%Cr
alloy was fabricated using a blended element powder metallurgy approach. Micrograph of the samples after sintering
showed bright-circle structures and significantly decreased equiaxed structures. The number of plate-like structures
increased with prolonged sintering time. Microstructural changes occurred because of element diffusion resulting from
the prolonged sintering time. Moreover, the diffusion distance of each element also increased with prolonged sintering
time. Although elements can sufficiently diffuse during both sintering and furnace cooling, the diffusion distance during
sintering was considerably higher than that during furnace cooling for all elements. The diffusion distances of Cr and
Mo were the highest and lowest, respectively, during sintering and furnace cooling. This study showed that alloying
behaviour mostly occurred during sintering and was controlled by the diffusion of Mo atoms.
The purpose of this study was to examine the differing curves of the volar distal radius of healthy Malaysian Malays, so as to obtain detailed morphological information that will further the understanding of volar plate osteosynthesis in Malaysian Malays.
Sacroilliac joint diasthesis from high energy trauma is always complicated with chronic pain and long term morbidity. Open anterior stabilisation with plate allow direct reduction and stabilisation with biomechanically advantages. Here we report on four cases of pelvic injury with sacroiliac joint disruption treated with anterior plate stabilisation through a surgical approach similar to that used for anterior ring fractures.
The enormous need of orthopaedic (surgical) implants such as osteosynthesis plates is difficult to be fulfilled in developing countries commonly rely on imported ones. One of the alternatives is utilization of local resources, but only after they have been proven safe to use, to overcome this problem. Surface properties are some of the determining factors of safety for those implants. We have succeeded in developing prototype of osteosynthesis plate and the results indicate that Indonesian-made plates need improvement with regards to the surface quality of physical characterization.