SYSTEM AND METHOD FOR PRECISE PROSTHESIS POSITIONING IN HIP ARTHROPLASTY

• US 20140330281A1
• Filed: 09/28/2012
• Published: 11/06/2014
• Est. Priority Date: 09/29/2011
• Status: Active Grant

• Current Assignee: Arthromeda, Inc.
• Original Assignee: Arthromeda, Inc.
• Inventors: Aghazadeh, Mehran S.
• Granted Patent: US 9,572,682 B2
• Time in Patent Office: Days
• US Class Current: 606/102
• CPC Class Codes: A61B 17/1659 Surgical rasps, files, planes, or scrapers
• CPC Class Codes: A61B 17/1668 for the upper femur A61B17/164 takes precedence
• CPC Class Codes: A61B 17/58 for osteosynthesis, e.g. bone plates, screws , setting implements or the like A61B17/14, A61B17/16 take precedence
• CPC Class Codes: A61B 17/60 for external osteosynthesis, e.g. distractors, contractors
• CPC Class Codes: A61B 2034/107 Visualisation of planned trajectories or target regions
• CPC Class Codes: A61B 2090/061 for measuring dimensions, e.g. length
• CPC Class Codes: A61B 2090/067 for measuring angles
• CPC Class Codes: A61B 90/06 Measuring instruments not otherwise provided for
• CPC Class Codes: A61B 90/36 Image-producing devices or illumination devices not otherwise provided for
• CPC Class Codes: A61B 90/37 Surgical systems with images on a monitor during operation
• CPC Class Codes: A61F 2/32 for the hip
• CPC Class Codes: A61F 2/34 Acetabular cups
• CPC Class Codes: A61F 2/36 Femoral heads ; Femoral endoprostheses
• CPC Class Codes: A61F 2/46 Special tools or methods for implanting or extracting artificial joints, accessories, bone grafts or substitutes, or particular adaptations therefor
• CPC Class Codes: A61F 2/4607 of hip femoral endoprostheses
• CPC Class Codes: A61F 2/4609 of acetabular cups
• CPC Class Codes: A61F 2/4657 Measuring instruments used for implanting artificial joints for surgical instruments A61B90/06
• CPC Class Codes: A61F 2002/30617 Visible markings for adjusting, locating or measuring
• CPC Class Codes: A61F 2002/4658 for measuring dimensions, e.g. length
• CPC Class Codes: A61F 2002/4668 for measuring angles

Abstract

Provided are systems and methods for precise intra-operative placement and positioning of components of hip prostheses, particularly with respect to avoiding acetabular prosthetic implant malpositioning in the human hip. In one embodiment the system includes at least a pair of electronic sensors as tilt and direction sensors, which are positioned on the patient'"'"'s native bone structure and the prosthesis, plus at least one of an electronic angle sensor and an electronic leg length measurement unit, plus a computer processor running application software that is capable of receiving and using information from the various electronic sensors to calculate relevant angular relationships and, optionally, distance relationships. The system electronically measures a living subject'"'"'s pelvic tilt and position while lying in the lateral decubitus position during the surgery. The systems and methods provide accurate and precise measurements of the subject'"'"'s pelvic tilt, angle of inclination, and angle of forward flexion to the surgeon during the procedure by which the hip prosthesis is surgically implanted into the subject.

Claims

1-32. -32. (canceled)

33. A method for precise intra-operative positioning of a total hip prosthesis in a human subject, comprising:

determining the pelvic axis of a human subject in need of hip arthroplasty;

attaching a first electronic position sensor (ESI) to a bony anatomic site on the pelvic axis of the subject;

attaching a second electronic position sensor (ES2) to a cup impactor, wherein the first and second electronic position sensors are capable of acting in combination to report information useful to calculate the true angle of inclination and the true angle of forward flexion of the acetabular prosthetic cup;

contacting the cup impactor with an acetabular prosthetic cup that is to be implanted into the prosthetic implantation site in the patient;

attaching an electronic angle sensor to a structure selected from the group selected from native femoral neck, prosthetic femoral stem, and broach handle, wherein the electronic angle sensor is capable of reporting information useful to calculate the angle of anteversion of the structure to which it is attached;

transferring information from the first and second electronic position sensors to a computer processor running application software, wherein the application software calculates the true angle of inclination and the true angle of forward flexion of the acetabular prosthetic cup;

transferring information from the electronic angle sensor to the computer processor running application software, wherein the application software calculates the angle of anteversion of the structure to which it is attached; and

displaying results of the calculations on an electronic visual display device while the prosthesis is being surgically positioned for implantation into the subject.

34. The method of claim 33, wherein the calculated measurements are displayed on demand.

35. The method of claim 33, wherein the calculated measurements are displayed continuously.

36. A method for precise intra-operative positioning of a total hip prosthesis in a human subject, comprising:

determining the pelvic axis of a human subject in need of hip arthroplasty;

attaching a first electronic position sensor (ESI) to a bony anatomic site on the pelvic axis of the subject;

attaching a second electronic position sensor (ES2) to a cup impactor, wherein the first and second electronic position sensors are capable of acting in combination to report information useful to calculate the true angle of inclination and the true angle of forward flexion of the acetabular prosthetic cup;

contacting the cup impactor with an acetabular prosthetic cup that is to be implanted into the prosthetic implantation site in the patient;

attaching an electronic leg length measurement unit, comprising (i) a substantially planar bracket constructed and arranged to receive at least two securing pins spaced and oriented in accordance with the apertures of the axis guide;

(ii) a reflection pin; and

(iii) an electronic distance sensor (DS) capable of being attached to the bracket and capable of reporting, to the computer processor, information about its distance from the reflection pin;

transferring information from the first and second electronic position sensors to a computer processor running application software, wherein the application software calculates the true angle of inclination and the true angle of forward flexion of the acetabular prosthetic cup;

transferring information from the electronic distance sensor to the computer processor running the application software, wherein the application software calculates the distance between the distance sensor and the reflecting pin; and

displaying results of the calculations on an electronic visual display device while the prosthesis is being surgically positioned for implantation into the subject.

37. The method of claim 36, wherein the calculated measurements are displayed on demand.

38. The method of claim 36, wherein the calculated measurements are displayed continuously.

39. A method for precise intra-operative positioning of a total hip prosthesis in a human subject, comprising:

determining the pelvic axis of a human subject in need of hip arthroplasty;

attaching a first electronic position sensor (ESI) to a bony anatomic site on the pelvic axis of the subject;

attaching a second electronic position sensor (ES2) to a cup impactor, wherein the first and second electronic position sensors are capable of acting in combination to report information useful to calculate the true angle of inclination and the true angle of forward flexion of the acetabular prosthetic cup;

contacting the cup impactor with an acetabular prosthetic cup that is to be implanted into the prosthetic implantation site in the patient;

attaching an electronic angle sensor to a structure selected from the group selected from native femoral neck, prosthetic femoral stem, and broach handle, wherein the electronic angle sensor is capable of reporting information useful to calculate the angle of anteversion of the structure to which it is attached;

attaching an electronic leg length measurement unit, comprising (i) a substantially planar bracket constructed and arranged to receive at least two securing pins spaced and oriented in accordance with the apertures of the axis guide;

(ii) a reflection pin; and

(iii) an electronic distance sensor (DS) capable of being attached to the bracket and capable of reporting, to the computer processor, information about its distance from the reflection pin;

transferring information from the first and second electronic position sensors to a computer processor running application software, wherein the application software calculates the true angle of inclination and the true angle of forward flexion of the acetabular prosthetic cup;

transferring information from the electronic angle sensor to the computer processor running application software, wherein the application software calculates the angle of anteversion of the structure to which it is attached;

transferring information from the electronic distance sensor to the computer processor running the application software, wherein the application software calculates the distance between the distance sensor and the reflecting pin; and

displaying results of the calculations on an electronic visual display device while the prosthesis is being surgically positioned for implantation into the subject.

40. The method of claim 39, wherein the calculated measurements are displayed on demand.

41. The method of claim 39, wherein the calculated measurements are displayed continuously.