Search Results
AI Overview
A proximal femoral intramedullary nail (PFN) tension screw, often referred to as a lag screw or compression screw, is a key component of cephalomedullary nails used to stabilize femoral neck and intertrochanteric fractures. It is inserted through the nail into the femoral head, providing rotational stability and allowing for controlled compression, which reduces the risk of the "Z-effect" (screw migration).
Key Aspects of Proximal Femoral Nail Screws:
- Function: The screw acts as a load-bearing device, securing the femoral head and neck to the nail, which is placed in the femoral shaft. This allows for stable fixation and early weight-bearing.
- Design & Technology:
- Combined Compression: Modern systems often feature a combined screw and gear structure, allowing for linear compression along the nail.
- Threaded Design: Threaded proximal screw holes help prevent screw backout (screw loosening).
- Spiral Blade/Screw: Some systems, like the Trochanteric Femoral Nail Advanced (TFNA), use a spiral blade or specialized lag screw to improve purchase in osteoporotic bone.
- Placement and Size:
- Positioning: Optimal placement is usually in the center-center or center-inferior position in the femoral head on X-ray.
- Length: Typical screw lengths in the proximal femur are determined by measuring the distance from the lateral cortex to the femoral head, with 40mm often cited as optimal for certain anatomical locations.
- Contraindications & Risks: While efficient, improper placement or choosing an incorrect size can lead to complications such as nonunion, malunion, or nail migration.
- Examples: Systems like the Arthrex Femoral Nail System and others offer specialized screw configurations to handle various fracture types.
The primary goal of this screw is to achieve stability while allowing for anatomical, controlled reduction of the fracture site.
Show all
This is for informational purposes only. For medical advice or diagnosis, consult a professional. AI responses may include mistakes. Learn more
Show more
Web results
Nailing (long nail) for Intertrochanteric fractures
AO Foundation Surgery Reference
https://surgeryreference.aofoundation.org › adult-trauma
AO Foundation Surgery Reference
https://surgeryreference.aofoundation.org › adult-trauma
The trochanteric femoral nail advanced (TFNA) device is an intramedullary nail that uses a spiral blade or lag screw to obtain fixation in the femoral head.Read more
Determination of the safest level and screw length for ... - PMC
PubMed Central (PMC) (.gov)
https://pmc.ncbi.nlm.nih.gov › articles › PMC9903104
PubMed Central (PMC) (.gov)
https://pmc.ncbi.nlm.nih.gov › articles › PMC9903104
by M Aydin2023Cited by 5 — In conclusion, in retrograde femoral nailing, the safest level for the proximal locking screw is 1 cm superior to the LT, and 1 cm inferior the LT is dangerous ...Read more
Femoral Nail System
Arthrex
https://www.arthrex.com › trauma › femoral-nail-system
Arthrex
https://www.arthrex.com › trauma › femoral-nail-system
The Femoral Nail System is used for intramedullary fixation for fractures of the femur. The system contains unique screw configurations for both antegrade ...
Proximal Femoral Intramedullary Nail Tension Screw
Double Medical
https://www.doublemedicalgp.com › product-tag › pro...
Double Medical
https://www.doublemedicalgp.com › product-tag › pro...
Proximal femoral bionic nail was jointly developed on the basis of the original patent of “triangle stable structure” by Academican Zhang Yingze and the theory ...Read more
Intramedullary femoral nails: one or two lag screws? A ...
ScienceDirect.com
https://www.sciencedirect.com › article › abs › pii
ScienceDirect.com
https://www.sciencedirect.com › article › abs › pii
by CJ Wang2000Cited by 104 — In the proximal end of the nail, the lag screws are designed, in theory, to slide into the holes in the nail, and there is a small gap between each lag screw ...Read more
proximal femoral nail - ramic
Bioadvance
https://bioadvancelatam.com › uploads › tecnica-...
Bioadvance
https://bioadvancelatam.com › uploads › tecnica-...
PDF
Release and remove the Protection Sleeve for Lag. Screw (13031008) by pressing the button on the. Proximal Aiming Device (13031006). 12. SURGICAL TECHNIQUE · ...Read more
The best location for proximal locking screw for femur ... - PMC
PubMed Central (PMC) (.gov)
https://pmc.ncbi.nlm.nih.gov › articles › PMC4759882
PubMed Central (PMC) (.gov)
https://pmc.ncbi.nlm.nih.gov › articles › PMC4759882
by AA Karaarslan2016Cited by 8 — To avoid proximal locking screw deformation, locking screws should be placed in the level of the lesser trochanter in nailing of 1/3 middle and distal femur ...Read more
Web results
Intramedullary nailing - AO Surgery Reference
AO Foundation Surgery Reference
https://surgeryreference.aofoundation.org › adult-trauma
AO Foundation Surgery Reference
https://surgeryreference.aofoundation.org › adult-trauma
The proximal Schanz screw must be proximal and appropriately positioned to avoid blocking the nail. The distractor's distal screw should be outside the ...Read more
People also search for
Share
Facebook
Gmail
X
Reddit
WhatsApp