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PURPOSE OF THE STUDY: The purpose of this report was to study the repercussions of rotator cuff condition on unconstrained shoulder arthroplasty results. METHODS: Between 1986 and 1993, 40 unconstrained shoulder prostheses were performed (24 total and 16 hemiarthroplasties). At the time of the operation, rotator cuff condition was reported to be normal in 15 shoulders, atrophic in 10, scarred in 3, torn in 12. Clinical and radiographical results were analyzed and supplemented with a rotator cuff echography. Postoperative follow-up averaged 42.25 months (12 to 97 months). RESULTS: When the rotator cuff was intact at the time of operation, clinical results were the best at the time of review. Constant score, overall mobility, forward elevation, external rotation with the elbow along the side were better for intact than for atrophic, scarred or torn rotator cuffs (p < 0.01). Ruptures repaired by local tissue transfer or trapezo deltoidal flap substitution (3 cases) gave satisfactory results, whereas two dacron cuff prostheses failed. In the non repaired ruptures (7 cases), arthroplasty resulted in 3/4 fair or poor results. At the time of review, the total incidence of postoperative rotator cuff tears was high (12 cases), functional repercussions were variable. Among the 15 rotator cuff tears observed at the time of the review, the long head of the biceps was present and in place in 9 cases and ruptured in 6 cases. In these latter cases, Constant score (p < 0.01), the forward elevation (p < 0.01), external rotation with elbow along side (p < 0.05) and overall mobility (p < 0.05) were worse; moreover, humeral head superior migration was greater (p < 0.01). DISCUSSION: Our study confirms the superiority of clinical results when the cuff was intact at the time of the operation. The repair of rotator cuff tears seems to be justified. When the rupture has not been repaired, clinical results were fair or poor in 5 cases out of 7, the initial rupture spread to the other tendons in 3 cases out of 7. Secondary ruptures were frequent (12 cases). No predictive factor was identified, but an overlapping of the greater tuberosity appears to be detrimental. Among rotator cuff tears present at the time of review, long head of the biceps rupture jeopardized clinical results and was associated with a proximal migration of the humeral head which was significantly more severe than with an intact non displaced long head of the biceps. CONCLUSION: During unconstrained shoulder prosthesis implantation, it is therefore recommend to systematically repair any associated rotator cuff rupture, in order to avoid any greater tuberosity overlap relative to the prosthetic head and to preserve the long head of the biceps tendon which limits upward migration of the humeral head and improves prosthetic kinetics. 相似文献
3.
Toshimitsu Suzuki Osamu Yamada Yasuhiko Takahashi Yoshihisa Watanabe 《Fuel Processing Technology》1985,10(1):33-43
Hydroliquefaction of low-sulfur Australian coals (Wandoan and Yallourn) was studied using iron carbonyl complexes as catalyst. The addition of Fe(CO)5 (2.8 wt% Fe of coal) increased coal conversion from 48.6 to 85.2% for Wandoan coal, and from 36.7 to 69.7% for Yallourn coal in 1-methylnaphthalene at 425°C under an initial hydrogen pressure of 50 kg cm?2. When molecular sulfur was added to iron carbonyls (Fe(CO)5, Fe2(CO)9 and Fe3(CO)12), higher coal converions ( > 92%) and higher oil yields (>46%) were obtained, along with an increase in the amount of hydrogen transferred to coal from the gas phase (0.2 to 2.8%, d.a.f. coal basis). In the liquefaction studies using a hydrogen donor solvent, tetralin, Fe(CO)5S catalyst increased the amount of hydrogen absorbed from the gaseous phase and decreased the amount of naphthalene dehydrogenated from tetralin. The direct hydrogen transfer reaction from molecular hydrogen to coal fragment radicals seems to be a major reaction pathway. Organic sulfur compounds, dimethyldisulfide and benzothiophene, and inorganic FeS2 and NiS were found to be good sulfur sources to Fe(CO)5. From X-ray diffraction analyses of liquefaction residues, it is concluded that Fe(CO)5 was converted into pyrrhotite (Fe1?xS) when sulfur was present, but into Fe3O4 in the absence of sulfur. 相似文献
4.
5.
Moon Ho Lee Jong Oh Park Yasuhiko Yasuda 《Multidimensional Systems and Signal Processing》1990,1(4):389-398
in this paper, simple 1-D and 2-D systolic array for realizing the discrete cosine transform (DCT) based on the discrete Fourier transform (DFT) fo an input sequence are presented. The proposed arrays are obtained by a simple modified DFT (MDFT) and an inverse DFT (IDFT) version of the Goertzel algorithm combined with Kung's approach. The 1-D array requiresN cells, one multiplier and takesN clock cycles to produce a completeN-point DCT. The 2-D array takes N clock cycles, faster than the 1-D array, but the area complexity is larger. A continuous flow of input data is allowed and no idle time is required between the input sequences. 相似文献
6.
Yuya Hattori Michiyo Suzuki Zu Soh Yasuhiko Kobayashi Toshio Tsuji 《Artificial Life and Robotics》2012,17(2):173-179
The pharyngeal pumping motion to send food to the bowel is a rhythmic movement in Caenorhabditis elegans. This paper proposes a simulation-based approach to investigate the mechanisms of rhythm phenomena in the pharyngeal pumping motion. To conduct the simulations, first, we developed a pharyngeal muscle model including 29 cell models which simulate the activity of each cell as a membrane potential based on FitzHugh-Nagumo equations. Then, to compare the response of the model with that of C. elegans, we calculated the electropharyngeogram (EPG), which represents the electrophysiological responses of the pharyngeal cells, using the simulated membrane potentials. The results confirmed that our model could generate the EPG similar to that measured from C. elegans. We proposed a computer simulation of the pumping motion to investigate the mechanisms of rhythm phenomena in living organisms. 相似文献
7.
Yasuhiko H. Mori Takehiro Nosoko Atsushi Mikami Tetsuya Ohyama 《Chemical Engineering Communications》1990,92(1):95-102
The shape of interfaces formed by the contact of two liquid phases, immiscible with each other, and a gaseous phase can be predicted on the condition that the tension to work at each interface is known with a sufficient accuracy. In general, interfacial tension data available are not so accurate, however, as to be useful as they are in predicting the shape of interfaces, particularly when the spreading coefficient of either liquid (liquid 1) on the other (liquid 2) has a negative value of a small magnitude. Presented in this note is a simple method to rectify the interfacial tension data, with the aid of a measurement of the radius of a lens of liquid 1 of a known volume placed on the horizontal surface of liquid 2, and thereby make them usable for predicting interfacial geometries. The method is tested by applying it to benzene/water and n-pentane/water systems. 相似文献
8.
X.M. Tian S. Adhikari S. Adhikary H. Uchida M. Umeno T. Soga T. Jimbo 《Diamond and Related Materials》2005,14(11-12):1839
Nitrogen incorporated diamond like carbon films have been deposited by microwave surface wave plasma chemical vapor deposition (MW-SWP-CVD), using methane (CH4) as the source of carbon and with different nitrogen flow rates (N2 / CH4 flow ratios between 0 and 3). The influence of the nitrogen incorporation on the optical, structural properties and surface morphology of the carbon films were investigated using different spectroscopic techniques. The nitrogen has been incorporated into DLC:N films which was confirmed by the X-ray photoelectron spectroscopy (XPS) measurement. Moreover, the nitrogen incorporation was accompanied by a variation in the optical gap, which was attributed to the removal or creation of band tail states. 相似文献
9.
Electrocodeposition of Sm and Co on a Cu substrate was investigated in a molten LiCl-KCl-SmCl3 (0.5 mol.%)-CoCl2 (0.1 mol.%) system at 723 K. Phase of the deposited Sm-Co alloys could be controlled by electrolysis potential. SmCo3 was formed on a Cu substrate by potentiostatic electrolysis in the potential range of 0.20-0.90 V (vs. Li+/Li). Sm2Co17 was obtained in the potential range of 0.90-1.50 V. 相似文献
10.
Ryu Komatsu Ryo Nakazato Takeru Sasaki Akio Suzuki Naoyuki Senda Takuya Kawata Yasuhiro Jimbo Tomoya Aoyama Naoto Ohno Susumu Kawashima Hisao Ikeda Shingo Eguchi Yoshiharu Hirakata Shunpei Yamazaki Takashi Shiraishi Seiji Yasumoto Masataka Nakada Masataka Sato Chris Bower Darryl Cotton Andrew Matthews Piers Andrew Catalin Gheorghiu Johan Bergquist 《Journal of the Society for Information Display》2015,23(2):41-49
In this study, a 5.9‐inch foldable active‐matrix organic light emitting diode (AMOLED) display was developed. A folding test was performed repeatedly. The display survived the folding test (100,000 folds) with a curvature radius of 2 mm. To protect an organic light emitting diode (OLED) against moisture, inorganic passivation layers are provided on the upper and lower sides of the flexible display. Using our transfer technology, high density passivation layers can be obtained. The measured water vapor transmission rate of the layer is 7 × 10?6 g/m2?day or less, which improves OLED reliability. With these techniques, we have developed a book‐type display, which is repeatedly foldable like a book, and a tri‐fold display including a display area, which is foldable in three. 相似文献