Assessment – (Complimentary Taster Module)

Correct answer: A . <br>

Dynamization is the process of making an intramedullary nail less rigid. This allows the fracture fragments to move slightly, which can help to stimulate bone healing. It allows the fracture fragments to compress when the patient weight bears, which can help to promote healing.
It is important to note that dynamization is not always necessary. It is most commonly used in cases of delayed healing or nonunion. If the fracture is healing well, there is no need to dynamize the nail.

Correct answer: B . <br>
Yes, the radius of curvature of a nail is less than the radius of curvature of a femur. This means that a nail is more curved than a femur.

Correct answer: C . <br>

A 6mm solid intramedullary nail has 1/16 the torsional rigidity of a 12mm solid nail of the same material.

This is because torsional rigidity is proportional to the fourth power of the radius of the nail. A 6mm nail has half the radius of a 12mm nail, so it has 1/16 the torsional rigidity.

Torsional rigidity is a measure of how much a nail resists twisting. A nail with higher torsional rigidity is less likely to twist, which is important for preventing rotation of the fracture fragments.

Correct answer: B . <br>
An Ilizarov external fixator (also known as an Ilizarov frame) is a device used to treat fractures, lengthen bones, and correct deformities. It consists of metal rings that are attached to the bone with screws or wires. The rings are connected by rods, which allow the bones to be gradually moved into the desired position.

Correct answer: D. <br>

The following techniques can increase the strength and stability of an external fixation construct:

Use more pins: The more pins that are used to secure the fixator to the bone, the stronger and more stable the construct will be.
Use larger pins: Larger pins are stronger and more resistant to bending than smaller pins.
Place the pins closer together: The closer the pins are to each other, the more rigid the construct will be.
Place the pins in different planes: Placing the pins in different planes (such as one pin on the front of the bone and one pin on the back of the bone) will help to prevent the bone from rotating.
Use connecting rods of a larger diameter: Larger diameter rods are stronger and more resistant to bending than smaller diameter rods.
Use a hybrid fixator: A hybrid fixator is a type of external fixator that uses a combination of rings and bars. Hybrid fixators are generally stronger and more stable than traditional external fixators.

Correct answer: C . <br>
The components of an external fixator include:

Pins or wires: Pins or wires are inserted into the bone to anchor the fixator.
Rings or bars: Rings or bars are attached to the pins or wires to provide support and stability to the bone.
Connectors: Connectors connect the rings or bars to each other.
Clamps: Clamps tighten the rings or bars around the pins or wires to secure the fixator in place.
Some external fixators also have additional components, such as:

Hinges: Hinges allow the fixator to be adjusted to move the bone into the desired position.
Distraction rods: Distraction rods are used to lengthen bones.
Compression rods: Compression rods are used to compress bones.

Best Answer C<br>
For achieving the maximum axial stiffness, the ‘near-near’ and the ‘far-far’ screws should be inserted in each fragment.
If only 2 screws are to be used in each fragment, the nearest screw to the fracture i.e. 1 and the farthest screw from the fracture i.e. 3 are to be inserted.

Plate Span Ratio: Total Plate Length / Fracture Length:
2‐3 times in large comminuted fractures, screws close to fracture
&gt; 8‐10 times in short fractures, screws NOT too close to fracture but 1-3 empty holes in plate are usually efficient
A plate span ratio of 2-3 for comminuted fractures and 8- 10 for simple fractures should serve as a guide for plate selection
In other words, when bridging a simple fracture, the use of a relatively longer plate and increased screw spread of the innermost screws will result in a lower implant strain

Best Answer .C. <br>
For achieving the axial compression, screw no 3 should be inserted first, which is inserted in the neutral mode. The aim of this maneuver is to create an “axilla” into which the other fragment can be compressed and locked either with a compression screw or using a push-pull technique.