Once variation of a system for total knee replacement includes: a first alignment guide defining first set of guides that locate a first set of pins on a first bone of a joint in extension and defining a reference surface relative to the first set pin guides; a second alignment guide constrained relative to the first alignment guide by the reference surface and defining a second set of guides, relative to the first set of guides, that locate a second set of pins on a second bone of the joint; a first cut guide located by the first set of pins and defining a first cut plane for resecting the first bone; and a second cut guide located by the second set of pins and defining a second cut plane, linearly offset from the first cut plane, for resecting the second bone.

Embodiments of the invention include a cloud-assisted rehabilitation system for assisting in the rehabilitation of musculoskeletal conditions, and a method for rehabilitating patients having musculoskeletal conditions. A rehabilitation portal can aggregate and de-identified musculoskeletal rehabilitation information that is gathered from various intelligent musculoskeletal rehabilitation apparatuses attached to a group of patients. The rehabilitation portal can facilitate crowd communication among the group of patients. A particular rehabilitation experience can be compared with other rehabilitation experiences and data from other patients. The rehabilitation portal can also facilitate crowd communication among a group of healthcare professionals so that the plurality of healthcare professionals can communicate with each other and compare information regarding different rehabilitation experiences based at least on the aggregated de-identified musculoskeletal rehabilitation information.

Systems and methods are disclosed for measuring a femoral alignment of a femur of a patient via a surgically implanted measurement device. An exemplary method may include: receiving, via at least one processor, first data from the measurement device, wherein: a housing of the measurement device is coupled to a musculoskeletal system of a patient; and the first data includes a plurality of measurements from each of an accelerometer and a gyroscope included with an inertial measurement unit disposed within the housing; determining the femoral alignment based on the first data; and causing a display to output the determined femoral alignment.

A kit includes a distractor, a plurality of trial elements, and at least one sensor. The distractor is configured to separate a first bone from a second bone by adjusting the distance between a first member and a second member, and is configured to receive at least one sensor in the first portion. Each of the trial elements corresponds to one of a plurality of surgical implants, is configured to be temporarily coupled to the second bone so as to evaluate suitability of the corresponding one of the plurality of surgical implants for implantation, and is configured to receive at least one sensor. The at least one sensor is configured to be received in the distractor or one of the trial elements, and is configured to record a magnitude of a force, a direction of application of a force, a pressure mapping, or a location of application of a force.

Disclosed herein is a method for evaluation knee stiffness and knee damping. The method may include the steps of releasing a subject's leg from an extension position to allow the leg to oscillate under gravity, tracking a knee angle and at least one joint motion characteristic during the oscillation, determining a knee joint torque and a knee gravitational moment from the knee angle and the joint motion characteristic, and determining a knee stiffness and a knee damping from the joint torque and the knee gravitational moment.

A surgical apparatus configured to be placed in the musculoskeletal system to precisely separate a first bone from a second bone. The surgical apparatus has one or more sensors to measure one or more parameters and supports one or more bone cuts for installing a prosthetic component. The surgical apparatus has at least one distraction mechanism configured to increase or decrease a height between a first support structure and a second support structure. A tilt mechanism comprises the at least one distraction mechanism. The tilt mechanism couples through a first pivot point and a second pivot point and adjusts a tilt of the second support structure relative to the first support structure. In one embodiment, loading applied to the second support structure is distributed between the first pivot point and the second pivot point during operation of the surgical apparatus.

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.

A data processing method for determining a range of motion of an artificial knee joint which connects a femur and a tibia via a medial ligament and a lateral ligament, wherein at least the femur comprises an implant which forms a medial condyle and a lateral condyle, the method comprising the steps of: acquiring the maximum lengths of the lateral ligament and the medial ligament: for a particular flexion angle of the knee joint; calculating a first virtual position between the femur and the tibia in which the lateral condyle of the femoral implant touches the tibia and the medial ligament is stretched to its maximum length; calculating a maximum valgus angle of the range of motion from the first virtual position; calculating a second virtual position between the femur and the tibia in which the medial condyle of the femoral implant touches the tibia and the lateral ligament is stretched to its maximum length; and calculating a maximum yarns angle of the range, of motion from the second virtual position.

A device for preparing a femur of a patient for receipt of a knee implant in both extension and flexion relative to a resected tibia plateau based on applying tension to medial and lateral collateral ligaments of said patient, comprising a tibial baseplate, a tensioner, the tensioner comprising a tensioner body having a tensioner portion, the tensioner portion affixed to the tibial baseplate, and an expander arm comprising an elongated body portion, a superior side of the elongated body portion having a spiked tip adjacent a posterior end thereof. The spiked tip interacts with an intracondylar notch under tension. The expander arm is operatively connected to the tensioner body via the tensioner portion, the tensioner portion configured for use in selectively raising and lowering the expander arm relative to the tibial baseplate to apply tension to the medial and lateral collateral ligaments in extension or flexion.

Disclosed is device for in vivo monitoring to detect infection associated with a prosthetically implanted device, such as a prosthetic knee. The device includes a sensor to detect the presence of one or more proteins secreted by body tissues in response to infection. The sensor may include a surface with a molecular imprint of the protein connected with a potentiometric or amperometic measuring device to detect when the protein bonds with the implanted surface. The device further includes an inductive coil coupled with a corresponding coil located outside the body. Electrical power for operating the measuring device and other circuitry is provided by inductive coupling between the coils. Signals indicating whether the protein is detected are communicated from the device to the external circuitry connected with the external coil.