Precise femoral component positioning for hip replacement surgery

Abstract

A method for accurately positioning the acetabular cup in a minimally invasive total hip arthroplasty (THA), comprising the steps of (a) placing the cup in roughly the correct position in the acetabulum using a acetabular component placement tool, (b) taking a first abduction reading and a first anteversion reading using a gyroscopic positioning unit aligned with the acetabular component placement tool, (c) taking an image of at least a portion of the cup using a radiography unit, (d) using the image to determine the actual orientation of the cup and required position of the cup to properly orient the acetabular component, (e) incrementally altering the position of the cup by using a striking tool, (f) taking new abduction and anteversion readings using the gyroscopic unit to determine the relative movement of the cup caused by the tapping, and (g) repeating any of the steps as necessary.

Description

CROSS-REFERENCES TO RELATED APPLICATIONS[0001]This patent application is a continuation-in-part application of U.S. patent application Ser. No. 13 / 431,944, filed Mar. 27, 2012, entitled “Precision Hip Replacement Method,” which claims the benefit of U.S. Provisional Application No. 61 / 528,744, filed Aug. 29, 2011, and U.S. Provisional Patent Application No. 61 / 567,869, filed Dec. 7, 2011. All applications are incorporated herein by this reference thereto.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]This invention relates to the field of minimally invasive surgical techniques for a joint replacement, and more particularly, methods for accurately positioning components for hip or knee joint replacement procedures.[0004]2. Description of the Related Art[0005]During the course of total hip arthroplasty, acetabular and femoral prostheses are placed. In order for the implants to function up to their capacity, generally meaning greater than twenty (20) years of clinical ...

AI Technical Summary

Benefits of technology

The patent describes a method for preparing and installing a femoral prosthetic using a laser pointer. This helps ensure that the femoral broach is properly aligned with the femur. The laser pointer creates a visible line or spot that aligns with the line of attack of the femoral broach, making it easier to target the accepted anatomical landmarks such as the center of the popliteal space. Overall, this helps improve the accuracy of the femoral bone preparation and implantation.

Problems solved by technology

Studies have shown, however, that a substantially large percentage of surgeries result in cups that are not within this range.

This supports the proposition that traditional techniques have been considered by many to be unreliable for determining proper positioning of the acetabular cup or femoral component.

The so-called traditional guides, or line-of-sight, have been in use for over 40 years and are very helpful, but not as reliable as one would hope.

Unfortunately, in spite of the promise of improved results, the reluctance of patients to be exposed to a significant amount of radiation during a CT scan, the significant cost of such a test against a simple intraoperative x-ray treatment, the total cost of the computer guidance system (many hundreds of thousands of dollars plus the ongoing cost of support annually as the machine is maintained and updated), the incalculable cost to the healthcare system, and the patient of an unpredictable workflow as system breakdown occurs frequently, add operation time and potential risk to the patient, as well as considerable cost.

Consequently, this method has not been widely adopted.

Furthermore, in spite of the existence of such tools, the current success rate for acetabular component positioning is only sixty percent (60%).

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