Callus Plate

Callus Micro motion locking plate for micro motion at fracture fragment induces earlier callus formation, stronger fracture healing & reduces the chances of non-union.

Callus micromotion small locking plate – Thickness 3 mm. (2.7 mm LHS)

Callus micromotion Narrow locking plate – Thickness 3.5 mm. (3.5 mm LHS)

Callus micromotion Broad locking plate – Thickness 5.5 mm. (5.0 mm LHS)

Plate thickness is the same as a conventional locking plate, but the plate is 2 times stronger compared to a simple locking plate of the same thickness because it is the combination of 2 plates, a flexure plate, and the top support plate, plus “C’ Channel design of the top support plate have improved the strength.

So, the patient can be allowed for immediate full Load bearing and micromotion start immediately.

Callus Micro Motion Plate Design

The need to make a callus Plate is, Fast fracture healing and allow controlled micromotion but the Plate should be stable that should not allow Bending or Plate breakage at a high mechanical load applied on the plate at the early full mobilization of the patient. The Callus plate is made up of 2 combination plates known as the flexure plate and the top support plate.

Flexure plate

The flexure plate has Horizontal spring type flexure and locking hole. The horizontal spring-type flexure is made by many horizontal cuts. These horizontal cuts developed on the plate allow the plate to give spring action when tension or compression is applied to the plate.

When the load is applied to this inbuilt compression spring flexure, it compresses and the gap between the flexure reduces when the load is released gap between the flexures comes in the original state like spring. Inbuilt compression spring-type flexures that allow vertical spring action, in medical terminology we call it controlled micromotion. These compression flexures be seen after the assembly of the flexure plate and the top support plate, the complete assembly of the flexure plate and the top support plate called the callus plate. Compression flexure can have different geometry

Locking holes is threaded holes that receive the threaded conical head of the screw, a screw with a threaded undersurface is used to fasten the plate to the bone. As the screw is tightened in the plate hole. The threads lock and a fixed-angle construct is created. Once secured, the toggle does not occur as the screw is locked in the plate. the strength of the fixation equals the sum of all screw-bone interfaces rather than that of the single screw’s axial stiffness or pullout resistance.

Top support plate

The need for the top support plate is to give support to the flexure plate. Because of horizontal cuts flexure plate is weak and it can easily bend or brake when the load is applied. The top support plate prevents bending or breakage of the flexure region and flexure plate. The top support plate is a box-type plate that has 4 corners that further increase the strength of the top support plate and flexure plate.

The top support plate has different slot geometry like a male slot or female slot or slanted slot. Flexure plate has also reciprocating geometry with a top support plate. If the top support plate has a female slot flexure plate has a matching male slot or groove. If the top support plate has a male slot flexure plate has a matching female slot or groove. If the top support plate has a slanted slot flexure plate has a matching slot or groove. The top support plate is fixed with the Flexure plate by first matching the slot or groove and then sliding up to the flexure region. Finally, single or multiple screws are attached through both plates that prevent sliding of the top support plate on the flexure plate but do not interact with flexure movement.

Controlled micro motion external fixator rod

Allow controlled micro motion at fracture site, rod is stable that does not allow bending or torsional movement or limb shortening.

Design

Micro motion external fixator rod is made up of 2 cylindrical tubes known as proximal tube and distal tube. The 1/3 portion of the distal tube goes into the proximal tube. The top portion of the distal tube is attached to the proximal tube. The distal tube has inbuilt compression spring-type flexures that allow vertical spring action.

Conventional Rod pin fixator is a cantilevered system and does not allow axial controlled vertical Micro motion at the fracture site like a ring fixator. There is a high incidence of delayed union or nonunion unless the fixator is modified or early bone grafting is carried out.