Abstract: The invention relates generally to orthopaedic implants, and more particularly to orthopaedic implants having data acquisition capabilities and their use in monitoring and diagnosing fracture healing. RSA is also disclosed as a method for measuring inter-fragmentary movement in long bone fractures in order to confirm whether the fracture is reduced and for detecting changes in stiffness of the healing callus.

Abstract: A multi-layer, fiber-reinforced composite orthopaedic fixation device having a design selected based on a desired characteristic of the orthopaedic fixation device. The design may be selected according to a model of the device, the model defining design constraints, and the design may comprise a pattern of the fiber angle for each layer. The selection of a design may be analyzed using finite element analysis to determine whether the design will comprise the desired characteristic.

Abstract: A load-bearing medical implant is disclosed that includes a load-bearing structure with a cavity extending into the outer surface of the structure. The cavity accommodates a sensor that is held in a fixed position within the cavity by an encapsulant. The cavity is covered by a plate that is welded over the cavity in close proximity to the sensor and encapsulant to provide a seal over the cavity and the electronic component without causing thermal damage to the encapsulant or sensor despite the close proximity of the encapsulant and sensor to the welded areas of the plate and structure. Methods for encapsulating the sensor in the cavity, methods for encapsulating a wire bus leading from the sensor through a channel in the implant and methods for pulsed laser welding of weld plate over the sensor and encapsulant with thermal damage to either are disclosed.

Abstract: A system and method for communicating with a medical implant is disclosed. The system (10,210,310,410) includes on-board electronics, a signal generator (15,215), an amplifier (16,216), a coil (14,214), a receiver (22,222), and a processor (20,220). The on-board electronics (100, 110) include a power harvester, a sensor, a microprocessor, and a data transmitter. The signal generator (15,215) generates a first signal, the amplifier (16,216) amplifies the first signal, the coil (14,214) transmits the amplified signal, the power harvester receives the first signal and transmits a data packet (18,218) containing data, the receiver (22,222) receives the data packet (18,218), and the processor (20,220) either processes the data or sends the data to a data storage device.

Abstract: A system (800) for processing accelerometer data is disclosed. The system (800) includes an accelerometer (806), a first processor (810), a power supply (816), and a second processor (804). The accelerometer (806) measures a physiological acceleration parameter. The first processor (810) is operatively connected to the accelerometer (806). The first processor (810) is configured to receive the acceleration parameter from the accelerometer (806) and configured to output machine readable acceleration data. The machine readable acceleration data includes time domain accelerometer data. The power supply (816) is electrically connected to the first processor (810). The second processor (804) is configured to receive the machine readable acceleration data and transform the time domain accelerometer data into frequency domain accelerometer data. The frequency domain accelerometer data may be used to estimate patient healing status.

Abstract: A system (110, 150) for targeting a landmark (114, 160) is disclosed. The system includes an instrumented medical implant (112, 152), a control circuit (118, 153), a power supply (120, 157), and a landmark identifier (122, 154). The instrumented medical implant (112, 152) has one or more landmarks (114, 160) and each landmark (114, 160) has a corresponding coil (116, 162). The control circuit (118, 153) is electrically connected to the corresponding coil (116, 162), and the power supply (120, 157) is electrically connected to the control circuit (118,153). The landmark identifier (122, 154) has a magnetic sensor (124, 155) for sensing the corresponding coil (116, 162).

Abstract: An instrumented orthopaedic implant, such as an intramedullary (IM) nail, is disclosed. The implant has the capacity to provide an accurate measurement of the applied mechanical load across the implant. The implant includes sensors and associated electronic components located in recesses on the outer surface of the implant. The implant houses the sensing apparatus, the interface circuitry, the data transmitter, and the power receiver. The hermetically sealed housing is adapted for implantation in the body of a patient. The implant is used with a controller which communicates with it by telemetry, and there is an acting unit connected to the electronic components which is adapted to carry out a function based upon a condition detected by the sensors.