A histological study on the tendons at chiasma plantare in pes cavus.

INTRODUCTION: In the dysfunction of large muscles of the leg, tendon transfer surgery is found to be very helpful in restoring the normal function of these muscles. The tendons involved in the chiasma plantare play a major role in this regard. OBJECTIVE: The present cadaveric study has been carried out in cadavers presenting pes cavus. MATERIAL AND METHODS: Cadaveric feet presenting pes cavus were identified based on their foot prints. All these tendons and their interconnections were subjected to histological procedures. The sections of the tendons were stained with hematoxylin and eosin in order to identify the underlying pathologies in the tendons. RESULTS: Various types of tendinous interconnections between the tendons of flexor digitorum longus and flexor hallucis longus were noted. The histological findings showed infiltration of lymphocytes in the tendon sheath indicating tenosynovitis and tendinitis. This could be attributed to the compression of the tendons. A few tendons were also stretched due to the skeletal framework of the foot in pes cavus. The bones along the medial longitudinal arch in pes cavus feet could tend to develop spurs or elongated tuberosity that could impinge on the tendons causing the tendons to stretch and elongate. CONCLUSION: In harvesting the tendons for grafting, the surgeons must be aware about the pathologies involved, such as tendinitis or tenosynovitis, in order to reduce the time taken for the healing of the graft post-surgery. These variations and histological findings can sub-serve as an efficient guide for the restoration of non-functioning muscles of the lower limb.

Infrared spectroscopic study on the thermal decomposition of external and internal gelation products of simulated mixed oxide nuclear fuel.

The thermal decomposition of urania-ceria gel corresponding to the composition U(0.7)Ce(0.3)O(2+x) obtained through external and internal gelation routes were studied using infrared spectroscopy (IR). In the case of externally gelated compound, the gel decomposes with the release of H2O and NH3 below 500 degrees C. A part of the NH3 released is entrapped in the solid and above 500 degrees C self reduction occurs in which U(VI) in the gel is reduced to U3O8. The decomposition products were identified to be U3O8 and CeO2. In the case of internally gelated compound, decomposition similar to the one for externally gelated compound occurred below 500 degrees C. Above 500 degrees C the carbon present in the gel reduced U(VI) to UO2 which formed solid solution with CeO2 around 650 degrees C.