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Plantar pressure, ground reaction force and body-segment kinematics measurements are largely used in gait analysis to characterise normal and abnormal function of the human foot. The combination of all these data together provides a more exhaustive, detailed and accurate view of foot loading during activities than traditional measurement systems alone do. A prototype system is presented that integrates a pressure platform, a force platform and a 3D anatomical tracking system to acquire combined information about foot function and loading. A stereophotogrammetric system and an anatomically based protocol for foot segment kinematics is included in a previously devised piezo-dynamometric system that combines pressure and force measurements. Experimental validation tests are carried out to check for both spatial and time synchronisation. Misalignment of the three systems is found to be within 6.0, 5.0 and 1.5 mm for the stereophotogrammetric system, force platform and pressure platform, respectively. The combination of position and pressure data allows for a more accurate selection of plantar foot subareas on the footprint. Measurements are also taken on five healthy volunteers during level walking to verify the feasibility of the overall experimental protocol. Four main subareas are defined and identified, and the relevant vertical and shear force data are computed. The integrated system is effective when there is a need for loading measurements in specific plantar foot subareas. This is attractive both in clinical assessment and in biomechanics research.

An evaluation of total hip replacement patients requires objective criteria that allow for the measurement of any changes in the biomechanics of the prosthesis and the effects of these changes on clinical findings. An evaluation of loading and joint movement during walking in these patients has been dealt with by many authors. In this study 15 patients who had undergone total hip replacement for coxarthrosis primary or secondary to congenital dysplasia were examined by kinematic and kinetic gait analysis, clinical evaluation, and radiographic evaluation of the position of the neocenter of prosthetic joint rotation. The patients with prostheses in congenital dysplasia presented with a pattern of walking that was significantly modified. In agreement with what is reported in the literature proximal positioning had less influence on gait parameters as compared to lateral dislocation. Furthermore, changes in positioning observed did not seem to have negative effects on joint loading, measured indirectly by the calculation of joint moments.

The use of interference screws in the reconstruction of the anterior cruciate ligament has increased over the years. Despite doubtless advantages there are some problems, too, some involving method of fixation, others the metallic nature of the screws. With the purpose of overcoming the latter, the authors evaluated the possibility of using interference screws made of bioabsorbable material. This preliminary study was conducted on two animal models (bovine and ovine); as a comparison parameter the torsional pair of screw insertion was used. A substantial similarity in the results thus obtained was observed that, together with the minor difficulties observed in the surgical field, contributes to the indication of the ovine model as preferential, based also on successive tests of functional validation conducted in vivo.

The results of the surgical treatment of valgus high tibial osteotomy were studied based on clinical and radiographic assessment and gait-analysis in 21 patients affected with arthrotic varus knee. Although tibial osteotomy has been in use for some time now, the reasons for its frequent failure are still not fully understood. A statistical analysis of the clinical and biomechanical parameters taken into account in this study have shown that hypercorrection in valgus is required to unload the medial compartment and to prevent the recurrence of deformity in varus and pain. Walking with the limb extrarotated may also be a compensatory mechanism, in order to reduce the adductor moment in the knee and overloading of the medial compartment.