A comparative study on water and dry coupling in photoacoustic tomography of the finger joints

We present a systematical study on comparison between water and dry coupling in photoacoustic tomography of the humanfinger joints.Compared to the direct water immersion of thefinger for water coupling,the dry coupling is realized through a transparent PDMSfilm-based water bag,which ensures water-free contact with the skin.The results obtained suggest that the dry cou-pling provides image quality comparable to that by water coupling while eliminating the wrin-kling of thefinger joint caused by the water immersion.In addition,the dry coupling offers more stable hemodynamic images than the water coupling as the water immersion of thefinger joint causes reduction in blood vessel size.

Bending Strength Properties of Finger Jointed Off-Cut Yellow Meranti （Shorea spp.） Wood

This study was undertaken to determine the bending strength properties of off-cut Yellow Meranti wood by applying the finger jointed techniques. The finger orientations that were used in this study are vertical and horizontal finger orientation. Specimens were bonded with PVAc （polyvinyl acetate）. The bending strength properties were determined by the three point and four point bending test method. The results show that vertical finger orientation has the higher mean of modulus of rupture and the modulus of elasticity value of 24.49 MPa （28.91 MPa） and 8,814 MPa （11,668 MPa） respectively. However, the tested specimen properties did not meet the minimum strength of the solid （control） specimens.

Innervated full thickness grafts in distal finger amputations

Innervated full thickness graft will be presented as an option to reconstruct a fingertip defect which might result in better sensibility than standard reconstruction using a full thickness graft without innervation. Also, anastomosing the nerve stumps can decrease the chance of developing neuroma.

Application of finite element analysis in properties test of finger-jointed lumber

Finger-jointed lumber production has now become the most extensively used method for spliced lumbers jointing together endwise.The properties of finger-jointed lumber are affected by many different factors such as the end-pressure.The main mechanical properties to be tested for struc-tural use finger-jointed lumber include the modulus of elasticity in static bending and the bending strength.The most commonly used method for testing these properties at present is the experi-mental test.In this study,we used finite element method to investigate the end-pressure range,the modulus of elasticity in static bending and the bending strength for Pinus sylvistriv var.finger-jointed lumber under three different fitness ratios(0 mm,0.1 mm,0.3 mm).With finite element analysis(FEA)modelling results compared with the experimental test results,it is possible to find the relationship between these two kinds of results and use the FEA to predict the properties of finger-jointed lumber.The FEA applied in the end pressure tests showed a narrower range com-pared with the modelling results.It indicated that the FEA could be used in the prediction of the end pressure for finger-jointed lumber.The modelling results for modulus of elasticity(MOE)test and bending strength(MOR)test showed about 20%discrepancies compared with the experimen-tal results.Moreover,the MOE modelling results showed the same trend as experimental results under three different fitness levels while the MOR modelling results showed the different trend.It can be concluded that the FEA is a feasible way in analysing the properties of finger-jointed lumber if the errors could be eliminated properly.Some modifications should be made in order to realize the prediction of the properties of finger-jointed lumber more accurately.

Vertical locking of the metacarpophalangeal joint of the little finger： A case report

Locking of the metacarpophalangeal （MCP） joint is commonly caused by hyperextension of the thumb or moderate flexion of the index or middle finger. We report a rare case of vertical locking of the MCP joint of the little finger in a 16-year old female after blunt trauma to the little finger. The MCP joint was locked when positioned at approximately 90-degree-flexion and could not extend actively or passively. A manual reduction was easily achieved and no immobilization was applied. Vertical locking of the MCP joint can be easily reduced, and immobilization is unnecessary after reduction. Correct diagnosis prior to reduction and differentiation from other types of locking are essential to prevent overtreatment.

Treatment of type III middle phalangeal neck fractures through a palmar approach： a case report

Phalangeal neck fractures occur almost exclusively in children. We present the case of a 49 years old man with a dislocated fracture of the neck of the middle phalanx with the distal fragment rotated at 180~, due to a traumatic circular saw injury to the left index, which was solved by anatomical reduction and bone fixation with two 1.5 mm Synthes screws and a temporary transarticular K- wire at the distal interphalangeal joint. Zone I flexor digitorum profundus repair was performed using a modification of the Kessler 4-strands core suture and a full-thickness skin graft from the hypothenar eminence was taken to cover the skin gap. At 6-month follow-up the patient was pain-free and with a total active movement equivalent to 190~. No radio-logical signs of avascular necrosis of the head of the middle phalanx or nonunion of the distal fragment was detectable with recovery to the previous manual work. Owing to the position of the phalangeal head maintained in position by the collateral ligaments an anatomic reduction from dorsal approach is difficult to be performed and a longitudinal trac- tion can render the reduction harder too. The volar approach permits an easier reduction of the fracture through a derotation of the distal fragment facing palmar.

Soft tissue distraction using pentagonal frame for long- standing traumatic flexion deformity of interphalangeal joints

Objective： Interphalangeal joint con- tracture is a challenging complication of hand trauma, which reduces the functional capacity of the entire hand. In this study we evaluated the results of soft tissue distraction with no collateral ligament transection or volar plate removal in comparison with traditional operation of contracture re- lease and partial ligament transection and volar plate removal. Methods： In this prospective study, a total of 40 pa- tients in two equal groups （A and B） were studied. Patients suffering from chronic flexion contracture of abrasive trau- matic nature were included. Group A were treated by soft tissue distraction using pentagonal frame technique and in Group B the contracture release was followed by finger splinting. Results： Analyzed data revealed a significant differ- ence between the two groups for range of motion in the proximal interphalangeal joints （P〈0.05）, while it was not meaningful in the distal interphalangeal joints （P〉0.05）. There was not a significant difference in the degrees of flexion contracture between groups （P〉0.05）. Regression analysis showed that using pentagonal frame technique significantly increased the mean improvement in range of motion of proxi- mal interphalangeal joints （P〈0.001）, while the higher the preoperative flexion contracture was observed in proximal interphalangeal joints, the lower improvement was achieved in range of motion of proximal interphalangeal joints after intervention （P〈0.001）. Conclusion： Soft tissue distraction using pentagonal frame technique with gradual and continuous collateral liga- ment and surrounding joint tissues distraction combined with skin Z-plasty significantly improves the range of mo- tion in patients with chronic traumatic flexion deformity of proximal and/or distal interphalangeal joints.