Implant Stability Measurement

Abstract

Disclosed herein are joint implants and methods for tracking joint implant performance. A method for monitoring a joint implant performance may include coupling a first implant to a first bone of a joint, the first implant including at least one magnetic marker. Coupling a second implant to a second bone of the joint, the second implant including at least one magnetic sensor to detect a position of the magnetic marker. Performing a first joint stress test to measure a baseline joint stability value, the baseline joint stability value being generated by the at least one magnetic sensor. Performing a second joint stress test to measure a second joint stability value, the second joint stability value being generated by the at least one magnetic sensor. Determining joint stability of the joint by comparing the baseline joint stability value to the second joint stability value.

1 . A method for monitoring a joint implant performance, the method comprising the steps of:
 coupling a first implant to a first bone of a joint, the first implant including at least one magnetic marker;   coupling a second implant to a second bone of the joint, the second implant including at least one magnetic sensor to detect a position of the magnetic marker;   performing a first joint stress test to measure a baseline joint stability value, the baseline joint stability value being generated by the at least one magnetic sensor;   performing a second joint stress test to measure a second joint stability value, the second joint stability value being generated by the at least one magnetic sensor,   and determining joint stability of the joint by comparing the baseline joint stability value to the second joint stability value.   
     
     
         2 . The method of  claim 1 , wherein the joint is any of a knee joint, shoulder joint, and hip joint. 
     
     
         3 . The method of  claim 1 , wherein the joint is a knee joint, the first implant being a femoral implant and the second implant being a tibial insert. 
     
     
         4 . The method of  claim 3 , wherein the first bone is a femur and the second bone is a tibia. 
     
     
         5 . The method of  claim 4 , wherein the first joint stress test and second joint stress test is any of a varus-valgus stress test, anterior-posterior drawer stress test and flexion-extension stress test. 
     
     
         6 . The method of  claim 5 , wherein the first joint stress test is performed intraoperatively. 
     
     
         7 . The method of  claim 6 , wherein the second joint stress test is performed postoperatively on the implanted joint implant. 
     
     
         8 . The method of  claim 7 , wherein the baseline joint stability value and the second joint stability value are tibiofemoral gaps between the femoral implant and the tibial insert measured by the at least one magnetic sensor. 
     
     
         9 . The method of  claim 8 , wherein a difference between the baseline joint stability value and the second joint stability value below a predetermined threshold indicates a stable joint. 
     
     
         10 . The method of  claim 9 , wherein a difference between the baseline joint stability value and the second joint stability value exceeding the predetermined threshold indicates an unstable joint. 
     
     
         11 . A method for monitoring a joint implant performance, the method comprising the steps of:
 coupling a first implant to a first bone of a joint;   coupling a second implant to a second bone of the joint, the second implant including a plurality of load sensors to detect a load and contact points between the first and second implants;   performing a first joint stress test to measure a baseline joint stability value, the baseline joint stability value being generated by the load sensors;   performing a second joint stress test to measure a second joint stability value, the second joint stability value being generated by the load sensors,   and determining joint stability of the joint by comparing the baseline joint stability value to the second joint stability value.   
     
     
         12 . The method of  claim 11 , wherein the joint is any of a knee joint, shoulder joint, and hip joint. 
     
     
         13 . The method of  claim 11 , wherein the joint is a knee joint, the first implant being a femoral implant and the second implant being a tibial insert. 
     
     
         14 . The method of  claim 13 , wherein the first bone is a femur and the second bone is a tibia. 
     
     
         15 . The method of  claim 4 , wherein the first joint stress test and second joint stress test is any of an internal-external rotational torque test, anterior-posterior shear force test and flexion-extension stress test. 
     
     
         16 . The method of  claim 15 , wherein the first joint stress test is performed intraoperatively. 
     
     
         17 . The method of  claim 16 , wherein the second joint stress test is performed postoperatively on the implanted joint implant. 
     
     
         18 . The method of  claim 17 , wherein the baseline joint stability value and the second joint stability value are load contact points between a medial and lateral condyle of the femoral implant and the tibial insert measured by the load sensors. 
     
     
         19 . The method of  claim 18 , wherein a difference between the baseline joint stability value and the second joint stability value under a predetermined threshold indicates a stable joint. 
     
     
         20 . A method for monitoring a joint implant performance, the method comprising the steps of:
 coupling a first implant to a first bone of a joint;   coupling a second implant to a second bone of the joint, the second implant including a plurality of load sensors to detect a load and contact points between the first and second implants;   establishing a baseline joint stability value;   performing a post-operative joint stress test to measure a second joint stability value, the second joint stability value being generated by the load sensors,   and determining joint stability of the joint by comparing the baseline joint stability value to the second joint stability value.