The authors have developed a new skeletal traction system for comminuted intraarticular fractures and fracture-dislocations in the hand. The system consists of two or three Kirschner wires and rubber bands, and is easy to assemble. It is more compact and comfortable than the banjo splint, and equally effective, and it allows early motion of the affected digits. A description of the technique is followed by the clinical results of seven cases of severe articular injuries in the hand. At the time of follow-up, the average range of the affected PIP joint motion was about 80 degrees. The final active motion of the injured DIP joint ranged from 0 to 40 degrees in flexion and that of the affected thumb (trapezial fracture) was not limited. The average follow-up period was 13.1 months.

A B S T R A C TWe have cross-checked the conventional theory of the spatial autocorrelation method and the consequence of seismic interferometry: the retrieval of the elastodynamic Green's function. Their mutual consistency is almost complete. The basic formulas of the conventional spatial autocorrelation theory can be derived by an alternative approach based on the retrieval of the elastodynamic Green's function. The only discrepancy is found with the average of the complex coherence function over azimuth in a wavefield dependent on azimuth. It is hypothesized, in discussion, that this discrepancy is due to the way of representing the wavefield in the background theory of seismic interferometry that can produce only wavefields moderately dependent on azimuth and that the mentioned consequence of seismic interferometry can also only make sense in a wavefield moderately dependent on azimuth.Our field experiment with a wavefield dependent on azimuth showed that the consequence of seismic interferometry in the logical framework of the conventional spatial autocorrelation theory is appropriate under such degrees of approximation as the measure proposed in this study, i.e., the deviation of the total dispersion curves is between about 10 and 16 per cent at the maximum from those averaged over azimuth.The acceptance of the retrieval of Green's function gives a proper physical meaning to the complex coherence function: the real part of the elastodynamic Green's function normalized by its zero-offset version. This makes it possible to take a deterministic approach rather than the statistical one on which the conventional spatial autocorrelation method is based and gives fruitful new aspects and perspectives. For example, the formula for the multi-mode case is given and the possibility of exploration of two or three dimensional velocity structures is suggested. I N T R O D U C T I O NExploration of the shear-wave velocity at the shallowest part of sediment is a key issue of engineering seismology and earthquake engineering. As these low-velocity layers amplify the seismic waves considerably and vary site by site abruptly, it is necessary to explore the underground velocity structure at each site. A commercial market was then formed for geotechnical geophysics directly related to civil engineering. This laterally varying amplification takes place not only for seismic * E-mail: tyokoi@kenken.go.jp waves due to tectonic earthquakes but also for the elastic waves produced by a surface shot and reflected by the velocity discontinuities that can be significant for production. If one wishes to extract useful information from the lateral variation of the reflected shear waves' amplitude, the effects of the shallowest sedimentary layers have to be taken into account, namely, they have to be quantitatively estimated and corrected. Among the various useful methods to estimate the underground shear-wave velocity structure, the usage of microtremor (ambient noise) is preferred by engineering seismologists because it does not require a...

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This report describes two cases of traumatic closed index extensor tendon rupture at the musclotendinous junction. Both patients were injured when their work gloves were caught in the revolving parts of machines, and both were treated surgically. One of the patients completely ruptured the index extensor digitorum communis (EDC) and the extensor indicis proprius (EIP) tendons at the musclotendinous junction of dorsal forearm. In this patient, the distal stump of the index EDC tendon was sutured to the middle EDC tendon in an end-to-side juncture. The other patient completely ruptured the EIP tendon and partially ruptured the index EDC tendon at the musclotendinous junction. In this patient, tendon transfer of the extensor digiti minimi (EDM) to the EIP tendon and plication of the index EDC tendon were performed. In both cases, surgical intervention enabled the patients to extend their index fingers almost normally; however, the former complained of inability to extend his index finger independently. Tendon transfer of the EDM in cases of index extensor tendon rupture at the musclotendinous junction is a good method to restore ability to independently extend the index finger. However, consideration should be given to anatomical variation in the little finger. The EDC tendon is sometimes absent leaving the EDM tendon as the only extensor tendon to the little finger.

We present a new approach of the Indirect Boundary Element Method (IBEM) for 3‐D topographic problems which can be used to deal with an infinitely spread free surface owing to the introduction of a reference solution, that is the analytical solution for the half‐space with a flat free surface. This approach is an efficient countermeasure for the non‐physical waves owing to the domain truncation which contaminates the computed results in the ordinary approach. Theoretical consideration shows that this newly proposed approach is a higher‐grade approximation than some existing ones and achieves a higher efficacy and accuracy than those of existing ones. The discretization of the resulting boundary integral equation for this formulation is carried out with triangular elements. Their contributions to the solution are calculated by Gaussian numerical integration except in the case where the wavefield is evaluated on the source element itself. For this case, we present an analytical formula based on the reasonable assumption that the elements are much smaller than the wavelengths appearing in the calculation. Several numerical examples used for validation show acceptably precise results.