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Updated: Jul 11, 2026
10:09
Adjustable Stiffness, External Fixator for the Rat Femur Osteotomy and Segmental Bone Defect Models
Published on: October 9, 2014
Locking plates increase the strength of dynamic hip screws
Dylan P A Jewell1, Sabina Gheduzzi, Mark S Mitchell
1University Hospital Birmingham NHS Trust, Raddlebarn Road, Selly Oak, Birmingham B29 6JD, UK. dylanjewell@yahoo.com
Injury
|September 21, 2007
Summary
A new dynamic hip screw (DHS) fixation using locking screws significantly improves construct strength compared to standard DHS plates. This enhanced stability is crucial for preventing DHS failure, especially in osteoporotic bone fractures.
Area of Science:
- Orthopedic biomechanics
- Biomaterials engineering
- Surgical implant technology
Background:
- Dynamic hip screw (DHS) fixation failure can lead to reduced patient mobility and overall health.
- Common DHS failure modes include lag screw cut-out and plate lift-off.
- Osteoporotic bone presents unique challenges for hip fracture fixation.
Purpose of the Study:
- To evaluate the biomechanical strength of a DHS construct utilizing a locking screw plate compared to a standard DHS plate.
- To determine if a locking screw plate enhances fixation stability in synthetic osteoporotic bone models.
Main Methods:
- Comparison of standard DHS plate versus DHS with fixed angle locking screws.
- Attachment of plates to synthetic osteoporotic bone models.
- Cyclic loading to simulate in-vivo forces and determine cycles to failure.
Main Results:
- The locking screw DHS construct demonstrated 2.6 times greater mean cycles to failure than the standard construct (285 vs. 108 cycles).
- Statistical significance was achieved with p=0.016.
Conclusions:
- A DHS with fixed angle locking screws offers superior construct strength, reducing the risk of fixation failure.
- This enhanced DHS fixation is particularly beneficial for patients with osteoporotic bone and complex fracture patterns.
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