Memory alloy compression fixing pin for fractures of tibial intercondylar eminences

Abstract

The invention provides a memory alloy compression fixing pin for fractures of tibial intercondylar eminences. The memory alloy compression fixing pin comprises a pin body made of memory alloy, the front end of the pin body is provided with a hook while the tail of the pin body is provided with a thread, and the tail end of the pin body is fittingly connected with a compression nut. A body of the compression nut is tubular and provided with an internal thread, and the tail end of the compression nut is expanded. The hook can be straightened after being soaked in ice water and automatically resets to the hook shape in normal temperature. The memory alloy compression fixing pin is applicable to all fractures of tibial intercondylar eminences and available for minimally invasive operation under monitoring of arthroscope regardless of sizes and comminuting degrees of fracture blocks, each fixing pin only requires one tibial bone tunnel, and convenience and quickness in operation are realized while operation time is shortened. In addition, due to rigid fixing, firmness in fracture fixation is realized, early function rehabilitation is allowed, small tibial bone tunnels and minimal damages are realized as well, and the memory alloy compression fixing pin is also suitable for fractures of tibial intercondylar eminences of adolescents without epiphyseal closure.

Description

technical field [0001] The invention belongs to the technical field of medical devices, and in particular relates to a memory alloy pressurized fixation needle for minimally invasive reduction and fixation of tibial intercondylar carina fractures under arthroscopy. Background technique [0002] Intercondylar eminence fracture of the tibia is an avulsion fracture of the insertion point of the anterior cruciate ligament at the intercondylar attachment of the tibia. With the increasing number of sports trauma and traffic accidents, the incidence of such fractures is increasing. Since the intercondylar eminence is the attachment point of the cruciate ligament, incorrect treatment will lead to instability of the knee joint in the future, and secondary damage to the main structures in the joint will seriously affect the function of the knee joint. With the gradual maturity and popularization of knee arthroscopy, minimally invasive treatment of tibial intercondylar avulsion fractur...

AI Technical Summary

Problems solved by technology

Hollow screw and absorbable nail fixation are only suitable for patients with large and complete bone fractures, and due to the obstruction of the femur, hollow screws and absorbable nails can only be screwed in from the front to the bottom when screwing in, and the screw screwing direction is related to the fracture The angle between the blocks is small, the pulling direction of the anterior cruciate ligament to the screw is about 90 degrees to the screw-in square when the knee joint is moving, and the shear force is large, which may easily cause the screw to loosen and cause fixation failure, and the screw-in direction is toward the popliteal fossa, there is a risk of injury to the blood vessels and nerves in the popliteal fossa

The strength of the absorbable screw is not enough, and it takes a long time to immobilize after operation

Steel wire fixation conforms to the principle of tension bands, but thin steel wires have low strength and are likely to cause tissue cutting; thick steel wires have good strength, but high rigidity and poor flexibility, making the operation more difficult

The Ethibond line belongs to soft fixation, and it is easy to prolong the fixation line when the joint is moving, making the fixation invalid; the fixation strength of the titanium cable is high and the flexibility is good, but the flexibility of the titanium cable makes it difficult to operate when passing through the anterior cruciate ligament. In addition, titanium cable fixation is also a banding fixation, which may cause tissue cutting. All banding fixations require drilling more than 2 bone tunnels in the tibia, which increases trauma

Images