System and method for noninvasive evaluation of prosthesis loosening, and/or fracture healing

A method for monitoring one or more mechanical properties of an assembly of rigid bodies, comprising:

• exciting, while the assembly is in a loaded condition, the propagation of mechanical waves in the assembly from a first rigid body to a second rigid body of the assembly via a contact interface therebetween;
• sensing physical quantities relating to the mechanical waves propagating in the assembly when the assembly is in the loaded condition;
• producing first electronic signals relating to the sensed physical quantities of the mechanical waves propagating in the assembly when the assembly is in the loaded condition;
• exciting, while the assembly is in a relaxed condition, the propagation of mechanical waves in the assembly from the first rigid body to the second rigid body of the assembly via the contact interface therebetween;
• sensing physical quantities relating to the mechanical waves propagating in the assembly when the assembly is in the relaxed condition;
• producing second electronic signals relating to the sensed physical quantities of the mechanical waves propagating in the assembly when the assembly is in the relaxed condition;
• determining, based on the first and second electronic signals, a state and/or a change in a state of a mechanical property of the assembly,
• wherein the first and second electronic signals each comprise:
• a) an electronic signal provided by the distant sensor;
• and at least one of the following:
• b) an electronic signal provided to the transducer to excite the propagation of mechanical waves;
• and c) an electronic signal provided by a near sensor located contralaterally to the distant sensor.

A computer program product comprising a program code for the execution of the following steps:

• exciting, while the assembly is in a loaded condition, the propagation of mechanical waves in the assembly from a first rigid body to a second rigid body of the assembly via a contact interface therebetween;
• sensing physical quantities relating to the mechanical waves propagating in the assembly when the assembly is in the loaded condition;
• producing first electronic signals relating to the sensed physical quantities of the mechanical waves propagating in the assembly when the assembly is in the loaded condition;
• exciting, while the assembly is in a relaxed condition, the propagation of mechanical waves in the assembly from the first rigid body to the second rigid body of the assembly via the contact interface therebetween;
• sensing physical quantities relating to the mechanical waves propagating in the assembly when the assembly is in the relaxed condition;
• producing second electronic signals relating to the sensed physical quantities of the mechanical waves propagating in the assembly when the assembly is in the relaxed condition;
• determining, based on the first and second electronic signals, a state and/or a change in a state of a mechanical property of the assembly,
• wherein the first and second electronic signals each comprise:
• a) an electronic signal provided by the distant sensor;
• and
• at least one of the following:
• b) an electronic signal provided to the transducer to excite the propagation of mechanical waves;
• and
• c) an electronic signal provided by a near sensor located contralaterally to the distant sensor, wherein the computer program product is executed on a computer.