Method for designing a patient specific orthopaedic device

Inventors

Gomes, Christophe

Assignees

EOS Imaging SA

Abstract

A method for designing a patient specific orthopaedic device intended for an osteoarticular structure of a patient, based on at least two two-dimensional radiographic images of the osteoarticular structure taken respectively in two offset image-taking directions, comprising the following steps: b) locating anatomical points on the radiographic images; c) determining at least one three-dimensional geometrical feature of the patient by matching the anatomical points b) located at step b); d) determining at least one three-dimensional size parameter of the orthopaedic device based on the geometrical feature of the patient determined at step c).

Core Innovation

The invention provides a method for designing a patient specific orthopedic device intended for an osteoarticular structure of a patient, based on only two two-dimensional radiographic images taken in two offset image-taking directions while the patient is in a standing position. The radiographic images are raw radiographic images deriving directly from detectors and are not derived from a 2D reconstruction implemented by a volumetric imaging technique such as CT-scanning or MRI. The method relies on the calibrated two two-dimensional radiographic images rather than volumetric imaging.

The method locates anatomical points on the radiographic images by manual identification by practitioner of a relevant part of the osteoarticular structure. The method then determines at least one three-dimensional geometrical feature of the patient by matching the anatomical points located on the two calibrated two-dimensional radiographic images, by placing in correspondence two representations of a given anatomical part. In this way, at least one patient-specific three-dimensional geometrical feature is obtained from the two offset 2D raw radiographic images.

From the three-dimensional geometrical feature, the method determines at least one three-dimensional size parameter of the orthopedic device in a three-dimensional space specific to the patient. The three-dimensional size parameter is chosen among a three-dimensional length, a three-dimensional angle, a three-dimensional curvature, a three-dimensional surface and a three-dimensional volume. After determining the size parameter, the method either forms the orthopedic device according to the size parameter or selects the orthopedic device among a plurality of orthopedic devices based on the size parameter.

Claims Coverage

The document includes three independent claims: a method claim, an apparatus claim, and another method claim. Across the independent claims, five inventive features are consistently presented: using two offset raw 2D radiographic images taken with the patient standing, locating anatomical points and matching calibrated representations, determining a 3D geometrical feature, determining a patient-specific 3D size parameter, and forming or selecting the orthopedic device.

Overall, the independent claims require using exactly two raw two-dimensional radiographic images taken in two offset image-taking directions with the patient standing, manually locating anatomical points, matching calibrated image representations to determine at least one three-dimensional geometrical feature, and deriving at least one patient-specific three-dimensional size parameter chosen from length, angle, curvature, surface, or volume, with subsequent forming or selecting of the orthopedic device. The apparatus claim parallels these elements as means for taking images, locating points, matching to determine a 3D geometrical feature, and determining the 3D size parameter.

Stated Advantages

Documented Applications

No documented applications found