Patient-specific pre-operative planning

Abstract

A method for pre-operative orthopedic planning includes obtaining only a high-resolution knee-joint scan of a patient, determining hip rotation center and ankle rotation center from anthropometric data based on personal data of the patient, and determining a mechanical axis of the knee joint based on the anthropometric data. The method also includes preparing at least a two-dimensional image model of the knee joint using the knee-joint scan and the determined mechanical axis, and preparing a pre-operative surgical plan based on the image of the knee joint.

1 . A method for pre-operative orthopedic planning comprising:
 obtaining only a high-resolution knee-joint scan of a patient;   determining hip rotation center and ankle rotation center from anthropometric data based on personal data of the patient;   determining a mechanical axis of the knee joint based on the anthropometric data;   preparing at least a two-dimensional image model of the knee joint using the knee-joint scan and the determined mechanical axis; and   preparing a pre-operative surgical plan based on the image of the knee joint.   
     
     
         2 . The method of  claim 1 , wherein the high-resolution scan is one of Magnetic Resonance Imaging or Computer Tomography scan. 
     
     
         3 . The method of  claim 1 , wherein the personal data include a height of the patient. 
     
     
         4 . The method of  claim 2 , wherein the personal data include gender, age and weight of the patient. 
     
     
         5 . The method of  claim 1 , wherein preparing a pre-operative surgical plan further comprises preparing a patient-specific alignment guide. 
     
     
         6 . The method of  claim 5 , wherein preparing a pre-operative surgical plan further comprises selecting an implant for the patient. 
     
     
         7 . The method of  claim 6 , wherein the implant is patient-specific. 
     
     
         8 . The method of  claim 1 , wherein preparing at least a two-dimensional image model of the knee joint includes preparing a three-dimensional image model of the knee joint. 
     
     
         9 . A method for pre-operative orthopedic planning comprising:
 obtaining only a high-resolution knee-joint scan of a patient;   taking a digital photographic image of the patient;   determining a hip rotation center and an ankle rotation center from the digital photographic image;   determining a mechanical axis of the knee joint based on the knee-joint scan and the hip rotation center and ankle rotation center;   preparing at least a two-dimensional image model of the knee joint using the knee-joint scan and the determined mechanical axis; and   preparing a pre-operative surgical plan based on the image model of the knee joint.   
     
     
         10 . The method of  claim 9 , wherein preparing a pre-operative surgical plan further comprises preparing a patient-specific alignment guide. 
     
     
         11 . (canceled) 
     
     
         12 . (canceled) 
     
     
         13 . The method of  claim 9 , wherein the digital photographic image of the patient is taken against a grid surface. 
     
     
         14 . A method of pre-operative orthopedic planning comprising:
 pre-operatively obtaining a scan of a joint of a patient;   pre-operatively obtaining personal data of the patient;   determining measurements of the joint using the personal data of the patient and anthropometric calculations;   determining a geometric feature of a bone of the joint based on the anthropometric calculations;   locating the geometric feature on an image model of the joint; and   preparing a pre-operative surgical plan based on the geometric feature and image model.   
     
     
         15 . The method of  claim 14 , wherein the joint comprises a knee joint, the bone comprises a femur, and the geometric feature comprises at least one axis of the femur. 
     
     
         16 . The method of  claim 15 , wherein measurements of the joint include distances between centers of rotation of the knee joint, an ankle joint and a hip joint of the patient. 
     
     
         17 . The method of  claim 16 , wherein the distances include hip height, hip offset, tibial height and ankle offset. 
     
     
         18 . The method of  claim 15 , wherein the at least one axis of the femur includes an anatomic axis and a mechanical axis. 
     
     
         19 . The method of  claim 14 , wherein personal data of the patient includes two or more of height, weight, body mass index, age, gender race, ethnicity, daily activity and disabilities of the patient. 
     
     
         20 . The method of  claim 14 , further comprising producing patient-specific instruments based on the pre-operative surgical plan. 
     
     
         21 . The method of  claim 14 , wherein the scan comprises a high-resolution scan from an MRI scanner or a CT scanner. 
     
     
         22 . The method of  claim 14 , wherein the image model of the joint comprise a three-dimensional image model.