Abstract:
A system and method is disclosed herein for measuring bone slope or tilt of a prepared bone surface of the muscular-skeletal system. The system comprises a three-axis accelerometer for measuring position, rotation, and tilt. In one embodiment, the three-axis accelerometer can be housed in a prosthetic component that couples to a prepared bone surface. The system further includes a remote system for receiving, processing, and displaying quantitative measurements from one or more sensors. A bone is placed in extension. The three-axis accelerometer is referenced to a bone landmark of the bone when the bone is in extension. The three-axis accelerometer is then coupled to the prepared bone surface with the bone in extension. The slope or tilt of the bone surface is measured. In the example, the slope or tilt of the bone surface corresponds to at least one surface of the prosthetic component attached thereto.
Abstract:
A system is disclosed herein for providing a kinetic assessment and preparation of a prosthetic joint comprising one or more prosthetic components. The system comprises a prosthetic component including sensors and circuitry configured to measure load, position of load, and joint alignment. The system further includes a remote system for receiving, processing, and displaying quantitative measurements from the sensors. The kinetic assessment measures joint alignment under loading that will be similar to that of a final joint installation. The kinetic assessment can use trial or permanent prosthetic components. Furthermore, adjustments can be made to the applied load magnitude, position of load, and joint alignment by various means to fine-tune an installation. The kinetic assessment increases both performance and reliability of the installed joint by reducing error that is introduced by elements that load or modify the joint dynamics not taken into account by prior assessment methods.
Abstract:
A prosthetic component suitable for long-term implantation is provided. The prosthetic component includes electronic circuitry and sensors to measure a parameter of the muscular-skeletal system. The prosthetic component comprises a first structure having at least one support surface, a second structure having at least one feature configured to couple to bone. The electronic circuitry and sensors are hermetically sealed within the prosthetic component. Sensors can be used to monitor synovial fluid in proximity to the joint to determine joint health. The prosthetic component can include a temperature sensor or a pH sensor. The temperature or pH of the synovial fluid can be correlated to a variety of joint conditions. Measurements over time can be analyzed for trends. The temperature or pH can be calibrated for the patient. For example, calibration can be for temperature or pH of a patient healthy joint. The measurements are compared against this patient reference.
Abstract:
A system and method of touchless interaction is provided for resolving a pivot point of an object where direct placement of a sensor at the pivot point is not practical. It applies to situations where the pivot point of a rigid object is inaccessible but remains stationary, while the other end is free to move and is accessible. The system maps the object's pivot point by way of an external sensor that detects constrained motion of the rigid object within a hemispherical banded boundary. It can also detect a geometric pattern and acceleration during the constrained motion to compensate for higher order rotations about the pivot point. Other embodiments are disclosed.
Abstract:
A prosthetic hip installation system comprising a reamer, an impactor, a tracking element, and a remote system. The tracking element can be integrated into the reamer or impactor for providing tracking data on the position or orientation. Alternatively, the tracking element can be housed in a separate module that can be coupled to either the reamer or impactor. The tracking element will couple to a predetermined location. Points in 3D space can be registered to provide a frame of reference for the tracking element or when the tracking element is moved from tool to tool. The tracking element sends data from the reamer or impactor wirelessly. The remote system receives the tracking data and can further process the data. A display on the remote system can support placement and orientation of the tool to aid in the installation of the prosthetic component.
Abstract:
A measurement system for measuring a parameter of the muscular-skeletal system is disclosed. The measurement system comprises a capacitor, a signal generator, a digital counter, counter register, a digital clock, a digital timer, and a data register. The sensor of the measurement system is the capacitor. The measurement system generates a repeating signal having a measurement cycle that corresponds to the capacitance of the capacitor. The capacitor comprises more than one capacitor mechanically in series. Electrically, the capacitor comprises more than one capacitor in parallel. In one embodiment, the capacitor includes a dielectric layer comprising polyimide. A force, pressure, or load is applied to the capacitor that elastically compresses the device.
Abstract:
A distractor suitable for measuring a force, pressure, or load applied by the muscular-skeletal system is disclosed. An insert couples to the distractor. The insert has at least one articular surface allowing movement of the muscular-skeletal system when the distractor is inserted thereto. The insert can be a passive insert having no measurement devices. A sensor array and electronics are housed within the distractor. The distractor can dynamically distract the muscular-skeletal system. A handle of the distractor can be rotated to increase or decrease the spacing between support structures. The measurement system comprises a sensor array and electronic circuitry. In one embodiment, the electronic circuitry is coupled to the sensor array by a unitary circuit board or substrate. The sensors can be integrated into the unitary circuit board. For example, the sensors can comprise elastically compressible capacitors or piezo-resistive devices. The distractor wirelessly couples to a remote system for providing position and magnitude measurement data of the force, pressure, or load being measured.
Abstract:
A sensor system uses positive closed-loop feedback to provide energy waves into a medium. It comprises a transducer (604), a propagating structure (602), and a transducer (606). A parameter is applied to the propagating structure that affects the medium. A sensor is coupled to a propagation tuned oscillator (416) that forms a positive closed-loop feedback path. The propagation tuned oscillator (416) includes a zero-crossing receiver (200) that generates a pulse upon sensing a transition of an energy wave from the propagating structure (602). The zero-crossing receiver (200) is in the feedback path that maintains the emission of energy waves into the propagating structure (602). The zero-crossing receiver (200) comprises a preamplifier (206), a filter (208), an offset adjustment circuit (210), a comparator (212) and a pulse circuit (218). The transit time, phase, or frequency is measured of the propagating energy waves and correlated to the parameter being measured.
Abstract:
A surgical apparatus is configured to support at least one bone cut for installation of a prosthetic component. The installed prosthetic component will have reduced alignment error. The surgical apparatus is configured to distract a first compartment to a first predetermined load value while allowing a moving support structure to pivot freely. A distraction lock mechanism is then engaged to prevent movement of a distraction mechanism that raises or lowers the moving support structure relative to a fixed support structure. The moving support structure has M-L tilt angle that is measured. A M-L tilt mechanism is engaged to forcibly equalize the first and second compartments. Engaging the M-L tilt mechanism prevents the moving support structure from freely pivoting. The at least one bone cut relates to the first and second compartments equalized and the M-L tilt angle.
Abstract:
A wirelessly powered medical implant system comprising: a power source system including: an automatic gain controller to receive input power, automatically adjust the input power based on a feedback signal with an offset phase delay, and provide the adjusted input power as output power; a source resonator to generate, based on the output power, a magnetic field to transmit wireless power via the magnetic field, and provide the feedback signal; and an offset phase delay circuit to receive the feedback signal from the source resonator, generate the offset phase delay, and include the offset phase delay with the feedback signal; and a medical implant including: an implant resonator to receive the transmitted wireless power via the magnetic field; and one or more sensors, wherein the feedback signal is based on inductive coupling of the magnetic field between the source resonator and the implant resonator.