Hypothesis Figure 1: Proximal end of human humerus bone fitted with the 3.5mm Proximal Humerus Plate...
1
Hypothesis Figure 1: Proximal end of human humerus bone fitted with the 3.5mm Proximal Humerus Plate before testing. Figure 2: Proximal end of human humerus bone fitted with the 3.5mm Proximal Humerus Plate after testing. Surgical plate fixation 9 human humerus bones were x- rayed to determine bone quality. Each bone is surgically given a simulated proximal humerus fracture at the surgical neck just below the head and the distal part of the bone is removed. All 9 bones were then repaired using a 3.5mm LCP Proximal Humerus Plate. 5 of the 9 bones were injected at the screw holes with Norian SRS injectable calcium phosphate cement. Figure 4A (Left) Overall average displacement in mm for each bone at each sensor. Figure 4B (Right) Graph of overall average displacement in mm at each sensor. If Norian SRS calcium phosphate cement is injected into the screw holes of a 3.5mm LCP proximal humerus plate, then there will be an increase in the stability of the implant. Mechanical bone testing The bone is anchored on a custom made aluminum plate using 2 screw-down U-brackets. The bone shaft is fitted with 2 sets of LVDT sensors that measure displacement of the bone at 2 points. Each set has a sensor that measures bone displacement in the X and Y direction. A specific force is applied to the head of the bone and displacement is measured. Non-Cemented Bone 2 3 4 5 Y Distal 0.773 0.833 0.426 1.120 X Distal 0.846 0.423 0.000 0.104 Y Proximal 0.955 0.957 0.714 0.756 X Proximal 0.424 0.398 0.386 0.386 Cemented Bone 6 7 8 9 10 Y Distal 0.828 0.395 0.006 0.824 0.570 X Distal 0.423 0.000 0.102 0.447 0.001 Y Proximal 0.957 0.313 0.037 1.167 0.534 X Proximal 0.405 0.138 0.102 0.148 0.291 Calcium phosphate cement does increase the stability of the LCP Plate by reducing displacement. Biomechanical Comparision of Locking Plates With and Without Cement for Internal Fixation of Proximal Humerus Fractures Laura M. Decker, RET Fellow 2009 Kenwood Academy High School RET Mentor: Dr. Farid Amirouche, PhD NSF- RET Program Abstract Introduction Conclusion Hypothesis Materials and Methods NSF Grant EEC-0743068 Prof. A. Linninger, RET Program Director Dr. Gerardo Ruiz, RET Program Managing Director Dr. Farid Amirouche, Research Mentor University of Illinois- Chicago Acknowledgements Motivation Proximal humerus fractures are Proximal humerus fractures are the the second most common fracture of second most common fracture of the upper the upper extremities extremities 1. 1. 75% of these injuries are in 75% of these injuries are in individuals over the age of 60 individuals over the age of 60 2 . . ✦ These patients may be These patients may be predisposed to these injuries predisposed to these injuries due to lowered bone densities due to lowered bone densities and osteoporosis and osteoporosis 2 . . Surgical Protocol cerebral artery In the upper extremities, proximal humerus fractures are the second most common type of fracture. 75% of these injuries occur in patients over the age of 60. This study’s objective is to compare the stability of the Synthes 3.5mm LCP Proximal Humerus Plate with and without Norian SRS calcium phosphate cement. 9 human humerus bones were dissected of all soft tissue and given a simulated 2 part fracture. Each specimen was repaired with a 3.5mm LCP plate and tested in vitro, (4 without cement, 5 with cement) using an Instron 5569 universal testing machine. Each bone is fitted with 4 LVDT sensors, and tested using varying forces ranging from 40-350 N. Data from each sensor was collected using LabView 8. Data analysis shows that the calcium phosphate cement does improve the stability of the implant and may improve the density of the bone around the fracture site. Testing Protocol References Source: Two-Part Surgical Neck Fractures of Source: Two-Part Surgical Neck Fractures of the Proximal Humerus1 the Proximal Humerus1 Source: Biomechanical Comparision of a unique Source: Biomechanical Comparision of a unique locking plate versus a standard plate for locking plate versus a standard plate for internal fixation of proximal humerus internal fixation of proximal humerus fractures in a cadaveric model.2 fractures in a cadaveric model.2 Image Source: Displacement/Screw Cutout after Image Source: Displacement/Screw Cutout after Open Reduction and Locked Plate Fixation of Open Reduction and Locked Plate Fixation of Humeral Fractures2 Humeral Fractures2 Figure 1: A: Showes a 2-part proximal fracture, (B) showes the same fracture repaired with a 3.5mm LCP proximal humerus plate. Figure A: Humerus that has been repaired with a 3.5mm LCP humerus plate. Figure B: Humerus bone attached to aluminum base plate fitted with LVDT sensors. A B
-
Upload
shauna-reed -
Category
Documents
-
view
224 -
download
1
Transcript of Hypothesis Figure 1: Proximal end of human humerus bone fitted with the 3.5mm Proximal Humerus Plate...
Hypothesis
Figure 1: Proximal end of human humerus bone fitted with the 3.5mm Proximal Humerus Plate before testing.
Figure 2: Proximal end of human humerus bone fitted with the 3.5mm Proximal Humerus Plate after testing.
Surgical plate fixation
9 human humerus bones were x-rayed to determine bone quality.Each bone is surgically given a simulated proximal humerus fracture at the surgical neck just below the head and the distal part of the bone is removed.All 9 bones were then repaired using a 3.5mm LCP Proximal Humerus Plate.5 of the 9 bones were injected at the screw holes with Norian SRS injectable calcium phosphate cement.
Figure 4A (Left) Overall average displacement in mm for each bone at each sensor. Figure 4B (Right) Graph of overall average displacement in mm at each sensor.
If Norian SRS calcium phosphate cement is injected into the screw holes of a 3.5mm LCP proximal humerus plate, then there will be an increase in the stability of the implant.
Mechanical bone testing
The bone is anchored on a custom made aluminum plate using 2 screw-down U-brackets.The bone shaft is fitted with 2 sets of LVDT sensors that measure displacement of the bone at 2 points. Each set has a sensor that measures bone displacement in the X and Y direction.A specific force is applied to the head of the bone and displacement is measured.
Non-Cemented
Bone 2 3 4 5
Y Distal 0.773 0.833 0.426 1.120X Distal 0.846 0.423 0.000 0.104
Y Proximal 0.955 0.957 0.714 0.756X Proximal 0.424 0.398 0.386 0.386
Cemented
Bone 6 7 8 9 10
Y Distal 0.828 0.395 0.006 0.824 0.570X Distal 0.423 0.000 0.102 0.447 0.001
Y Proximal 0.957 0.313 0.037 1.167 0.534X Proximal 0.405 0.138 0.102 0.148 0.291
Calcium phosphate cement does increase the stability of the LCP Plate by reducing displacement.
Biomechanical Comparision of Locking Plates With and Without Cement for Internal Fixation of
Proximal Humerus Fractures
Laura M. Decker, RET Fellow 2009Kenwood Academy High School
RET Mentor: Dr. Farid Amirouche, PhD NSF- RET Program
AbstractIntroduction
Conclusion
Hypothesis
Materials and Methods
NSF Grant EEC-0743068
Prof. A. Linninger, RET Program Director
Dr. Gerardo Ruiz, RET Program Managing Director
Dr. Farid Amirouche, Research Mentor
University of Illinois- Chicago
Acknowledgements
Motivation Proximal humerus fractures are the Proximal humerus fractures are the
second most common fracture of the upper second most common fracture of the upper
extremitiesextremities1.1.
75% of these injuries are in 75% of these injuries are in
individuals over the age of 60individuals over the age of 6022. . ✦These patients may be predisposed to These patients may be predisposed to these injuries due to lowered bone densities these injuries due to lowered bone densities and osteoporosisand osteoporosis22..
Surgical Protocol
cerebral artery
In the upper extremities, proximal humerus fractures are the second most common type of fracture. 75% of these injuries occur in patients over the age of 60. This study’s objective is to compare the stability of the Synthes 3.5mm LCP Proximal Humerus Plate with and without Norian SRS calcium phosphate cement. 9 human humerus bones were dissected of all soft tissue and given a simulated 2 part fracture. Each specimen was repaired with a 3.5mm LCP plate and tested in vitro, (4 without cement, 5 with cement) using an Instron 5569 universal testing machine. Each bone is fitted with 4 LVDT sensors, and tested using varying forces ranging from 40-350 N. Data from each sensor was collected using LabView 8. Data analysis shows that the calcium phosphate cement does improve the stability of the implant and may improve the density of the bone around the fracture site.
Testing Protocol
ReferencesSource: Two-Part Surgical Neck Fractures of the Proximal Source: Two-Part Surgical Neck Fractures of the Proximal
Humerus1Humerus1Source: Biomechanical Comparision of a unique locking plate Source: Biomechanical Comparision of a unique locking plate
versus a standard plate for internal fixation of proximal versus a standard plate for internal fixation of proximal humerus fractures in a cadaveric model.2 humerus fractures in a cadaveric model.2
Image Source: Displacement/Screw Cutout after Open Image Source: Displacement/Screw Cutout after Open Reduction and Locked Plate Fixation of Humeral Fractures2Reduction and Locked Plate Fixation of Humeral Fractures2
Figure 1: A: Showes a 2-part proximal fracture, (B) showes the same fracture repaired with a 3.5mm LCP proximal humerus plate.
Figure A: Humerus that has been repaired with a 3.5mm LCP humerus plate.Figure B: Humerus bone attached to aluminum base plate fitted with LVDT sensors.
A B
