Appendix A: Thesis Glossary
This appendix defines the terminology used throughout this thesis, to assist with understanding the technical terms that may not be familiar to the reader.5
Abduct: To draw away from a position near the middle axis of the body (as in a limb).
Alloy: A substance composed of two or more metals, or of a metal and non-metal fused together when molten.
Attenuate: The decrease or lessening of the amount of energy.
Bioactive: Having the effect of a living organism.
Biocompatibility: The condition of being compatible with living tissue, or not being toxic to living tissue.
Camera/Image sensor: A device that responds to the stimulus of light and transmits a resulting impulse.
Cartilage: Flexible connective tissue found in many areas in the bodies of humans and other animals
Cartilaginous joints: Joints that are connected by cartilaginous material.
Charged couple device (CCD): A semiconductor device, used as an optical sensor, which stores charge and subsequently transfers it to an amplifier and detector.
Diffraction: A modification that light undergoes, especially in passing by the edges of opaque bodies or through narrow openings.
5
The medical definitions listed here were obtained from the Marriam-Webster, Medline Plus Medical Dictionary, a service of the U.S. National Library of Medicine and National Institutes of Health. The general terminology was modified from the Marriam-Webster online dictionary, and Wikipedia Online Encyclopdia.
Extension: The unbending movement of a joint in a limb, that increases the angle between the bones of the limb and the joint.
Fibrous joints: Joints that are connected by fibrous, connective tissue such as collagen.
Field-of-view (FOV): The maximum observable area (as seen from a camera).
Flexion: A bending movement around a joint in a limb that decreases the angle between the bones of the limb and the joint.
f-number: Quantitative measure of the lens speed, and is the ratio of the focal length to the diameter of the lens opening.
Focal length: Measure of how strongly the system converges or diverges light; the distance (from the lens) over which the light rays are brought into focus.
Glenohumeral: The connection between the glenoid cavity and humerus of the shoulder.
Glenoid cavity: The shallow cavity of the upper part of the scapula, in which the humerus articulates.
Hounsfield unit (HU): Quantitative scale for describing radiodensity of a material, relative to the radiodensity of distilled water and air at standard pressure and temperature.
Humerus: The longest bone of the upper arm or forelimb extending from the shoulder to the elbow.
Image distortion: Deviation of projected image, in which straight lines of an object do not maintain similar straightness in the image.
Implant fixation: Surgical implementation and anchoring of joint replacement systems.
Intramedullary: Situated or occurring within the medulla of bone; use of the marrow space of a bonefor support.
In-vivo: Inside the living body, or within a living organism
Lens aperture: The opening or hole of a lens through which light enters.
Micromotion: Motion, such as that of an implant, occurring on the order of micrometers.
Monomer: A molecule that may bind chemically to other molecules to form polymers.
Osseointegration: The firm anchoring of a surgical implant by growth of bone around it, without fibrous tissue formation at the interface
Osteoarthritis: Degenerative joint disease that causes changes in the bone and cartilage at the joint, resulting in wearing down of joint surfaces.
Osteoporosis: Decrease in bone mass with decreased density and enlargement of bone spaces.
Perspective error: Difference in the image magnification as a result of object position/distance from the lens.
Photons: The unit intensity of light; smallest physical quantity of electromagnetic radiation.
Pixels: Small discrete elements that make up a image; picture elements.
Plasma spray: Coating in which melted or heated materials are sprayed onto a surface.
Polymer: Chemical compound consisting of repeating structural units or molecules.
Stereophotogrammetry: Technique used for the assessment of three-dimensional migration of joint replacement from bone, using an imaging technique to obtain real-time moving images of markers attached to the bone and implant.
Resolution: The detail and image holds; quantification of how close lines can be and still visibly resolved.
Sintered bead: Coating in which beads are diffused onto a surface at high temperatures.
Substrate material: Material on which a process is conducted;surface to which coating is applied.
Synovial joints: Most common of the moveable joints characterized by two bony surfaces covered with cartilage, contained in a fibrous capsule containing joint fluid.
Telecentric lens: Compound lens for which chief rays are parallel to the optical axis in a object/image space, making the object appear to be the same size independent of its location in space.
Tibia: The large, inner bone of the lower leg, located between the knee and ankle.
Ulna: One of the two bones located in the forearm, situated on the side of the forearm with the little finger, and articulates with the humerus in the elbow joint.
Appendix B: Specifications for Hardware of Optical System
This appendix details the specifications for the hardware used in the optical system discussed in Chapters 2,3,4,5 and 6.
Figure B.1: Specifications for the Basler Pilot AG piA 2400- 12gc Camera
(Adapted from the User Manual for GigE Vision Cameras; Document No.AW000151, Version 16; Basler Vision Technologies)
Figure B.2: Specifications for the Opto Engineering Telecentric Lens
Figure B.3: Specifications for the Advanced Illumination, Axial Diffuse Illumintor
(Adapted from sales sheet for Advanced Illumination products; http://www.1stvision.com/lighting/AI/uploads/products/DL072.pdf)
Appendix C: LabVIEW® Programs
This appendix shows the LabVIEW® back panels for the custom written programs used for calibration of the optical system and marker tracking data collection. These programs were used for Chapters 2 ,3, 4, 5 and 6.
Figure C.1: Back Panel of Calibration Program
The calibration program determines the vertical and horizontal pixel count for a rectangular region of interest of the calibration grid, set by the user. Based on the known spacing of the calibration grid (i.e., 0.1 mm), the pixel to millimeter conversion for the region of interest is found.
Figure C.2: Back Panel of the Optical Tracking Program
The optical tracking program incorporating a thresholding method to detect markers placed on landmarks of interest. The program determines the centroids of the detected markers, and tracks their respective (x,y) coordinates throughout the duration of the program. The program outputs the individual (x,y) coordinates of the marker, the length between the two points, and the corresponding load and position data from the materials testing machine.
Appendix D: Bland-Altman Plots for Optical System Validation
This appendix shows the individual Bland-Altman plots for the various regions of the optical system field of view (Region 1-9), as discussed in Chapter 2.
Figure D.1: Bland Altman plots for Region 1-9 of Horizontal Displacement
Individual plots for horizontal displacements within the nine regions of the image field of view. Regions 7 and 9 show some scatter points outside 95% limit of agreement (as indicated by dashed lines).
Figure D.2: Bland Altman plots for Region 1-9 of Vertical Displacement
Individual plots for vertical displacements within the nine regions of the image field of view. All regions show some scatter points outside 95% limit of agreement (as indicated by dashed line) for measurements of 0.5 mm.
Appendix E: Calculation of Optical System Accuracy
This appendix details the calculations used for determining the accuracy of the optical system as described in Chapter 2.
Accuracy as measured by percent error for the range of applied displacements (0.005- 0.500 mm).
Procedure 6:
1) Determine line of best-fit for data from optical system (i.e., measured) and micrometer (i.e., true) (Figure E.1).
Equation of best-fit: (Eq. F.1)
2) Evaluate errors in the measurements by creating a deviation plot from the data sets (Figure E.2).
( )
( )
3) Accuracy of the system, presented as % error of the range of output displacements:
- Range of output displacements from equation of best-fit:
o 0.507 mm-0.007 mm= 0.500 mm
6 As described in: Wheeler AJ, Ganji AR. 2010. Chapter 2: General Characteristics of Measurement