Double Medical 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 of “leverage-fulcrum reconstruction” proposed by Professor Zhang Dianying.
“Leverage-fulcrum reconstruction” theory
- The anatomy of the normal human hip joint is similar to a lever system. The fulcrum is located near the center of the femoral head, the lever arm of the medial compressive group is shorter, and the lever arm of the lateral tensile group is longer. Therefore, the hip joint can bear a greater weight and perform various actions.
- The purpose of the operation is to establish a new lever system through the internal fixation system to replace the original lever system until the fracture is healed.
- The postoperative stability of fracture depends on the type of fixation, and has no relationship with the types of the fracture.
- The fulcrum reconstruction position of new internal fixation system is more closer to the anatomical and physiological fulcrum, the more stable the postoperative fracture will be.
Nails:
- 130° CCD angle provide more options for different anatomy
- Medial-lateral angle of 5° allows insertion at the tip of the greater trochanter.
- Lateral flat cut design for easier insertion and lower pressure on the lateral wall.
- Smaller proximal diameter for protection of soft tissue.
- Distal long groove cutting disperse stress to prevent fractures around the nail.
- Anterior arch fits to the femoral anatomy
Large Compression Screw & Compression Screw
- Unique combined compression locking screw: continuous pressurization to eliminate the “Z” effect.
- The end of compression screw: fix the nail in the medial side of the medullary cavity to reduce the pressure of lateral wall.
- Gear structure: controllable rotation during reducitno provides linear pressurization.
Tension Screw:
- Self-tapping design facilitate intraoperative insertion.
- Torxdrive screwdriver, lower the risk of screw loose.
Locking Screw：
- Self-tapping design facilitate intraoperative insertion.
- Locking screw design with double lead thread for easier insertion.
- Torxdrive screwdriver, lower the risk of screw loose.
End Cap:
- Increase instant stable fixation for unstable fracture.
- Torxdrive screwdriver, lower the risk of end cap loose.
Aiming Shaft:
- Made of carbon fiber material, light weight and radiolucent.
- One jig for insertion of spiral blade and locking screw, no need to change instruments during operation.
- A guide wire can be inserted through the hole in aiming shaft to detect femoral anteversion angle and the depth of the nail into the medullary cavity.
- 针对不稳定骨折，提供两个克氏针孔用于临时抗旋转固定。.
适应症：
- 低位及延伸型转子下骨折
- 同侧转子骨折
- Multilateral fractures (proximal femur)
- 病理性骨折
禁忌症
- 股骨干骨折
- Isolated or combined middle femoral neck fractures
