A force-sensing catheter for diagnosing or treating the vessels found within a body or body space includes a center strut that is bonded, preferably thermally, along its longitudinal axis with the thermoplastic tubular member within which it is housed. The tubular member preferably has three layers: an inner layer, a braided layer and an outer layer. One or more semiconductor or metallic foil strain gages are affixed to the center strut in order to provide a measure of the bending and torsional forces on the distal tip of the catheter. Temperature compensation is achieved by having a temperature sensor near the strain gages and calibrating the catheter over a range of temperatures.