Trauma plating and fixation

Question 1

What are the general treatment goals of facial

reconstruction following trauma?

Answer 1

Restoration of form (facial height, facial width, and facial

projection) and function (airway, occlusion, mastication)

Question 2

What must fracture fixation accomplish to allow for direct (primary) bone healing?

Answer 2

Fixation must overcome natural forces acting across the
fracture site that would lead to mechanical instability and
poor apposition of the fractured segments.

Question 3

Name the two major types of plating materials.

Answer 3

● Metal

● Resorbable

Question 4

What material is most commonly used in metal

plating systems?

Answer 4

Titanium alloy

Question 5

How do the various trauma plate types differ?

Answer 5

● Alloy composition
● Plate hole size
● Screw head type

Question 6

What is the importance of bone fragment contact

in fracture healing?

Answer 6

Bone contact allows direct (primary) bone healing to occur
at a fracture site. Direct bone healing is a combination of
“contact healing” and “gap healing” in which there is no
formation of an intervening callus during repair. Indirect
(secondary) bone healing results from mechanical instability
and lack of close apposition of bone segments at a fracture
site. Secondary healing requires callus formation for bone
healing to occur.

Question 7

The term miniplate refers to what plate characteristic?

Answer 7

Plate thickness of 1.3 mm or less

Question 8

What characteristic does a locking plate possess?

Answer 8

As the screws are tightened into the plate, the screw heads
“lock” to the plate, thus stabilizing the segments without
the need to compress the bone to the plate and does not
require perfect contour with the underlying bone.

Question 9

What is the purpose of a compression plate?

Answer 9

It enhances interfragmentary compression by drawing bone fragments together by using eccentric drill/screw placement. It should be noted that trends in fracture management are moving away from using dynamic compression plates because of the higher complication rates secondary to greater technique sensitivity.

Question 10

What is the primary disadvantage of conventional

trauma plates

Answer 10

They require precise contouring of the plate to the underlying bone. If there are gaps between the plate and bone segments, tightening the screws will pull the bone
segments toward the plate, which can alter reduction.

Question 11

What is the potential disadvantage of bicortical

screw placement?

Answer 11

Damage of deeper structures including tooth roots and

underlying neurovascular structures

Question 12

What are the two basic types of fracture fixation?

Answer 12

● Load-bearing: Fixation that provides sufficient strength to
bear the entire physiologic load applied to the bone
during function
● Load-sharing: Fixation that relies on inherent bony
buttressing on either side of the fracture line to share
some of the load during physiologic function

Question 13

When is load-bearing fixation necessary?

Answer 13

Fractures with missing fragments, comminuted fractures, and fractures with inadequate bone buttressing to allow for
a load-sharing construct to be used (i.e., atrophic mandibular fractures)

Question 14

When is load-sharing fixation used?

Answer 14

In simple linear fracture repair where two opposing bone fragments provide sufficient bony buttressing to allow for adequate sharing of the physiologic forces across the fracture site without leading to fracture dislocation

Question 15

When applying a compression plate, what type of screw placement is required?

Answer 15

Eccentric drilling with the pilot hole away from the fracture site so that when the screws are tightened there is a vector that draws the bone fragments together

Question 16

What are the two basic types of screws?

Answer 16

● Self-drilling: Possess a sharp tip and do not require a pilot hole. These screws require more force for initial placement, so they are less ideal for comminuted or very
dense bone.
● Self-tapping: Possess a blunt tip that requires an initial pilot hole. They do not require as much force for insertion as self-drilling screws.

Question 17

What is an emergency screw?

Answer 17

An emergency screw is used when a standard screw strips
(continues to turn and will not tighten). The shaft is
fractions of a millimeter wider, increasing the chance of
bone purchase in a hole that has previously stripped.

Question 18

In general, what is the minimum number of screws that should be used on either side of a fracture fragment for load-sharing fixation?

Answer 18

At least two screws need to be used; however, three screws

are desirable, particularly when using a single plate.

Question 19

Define rigid fixation.

Answer 19

Any form of fixation that is strong enough to prevent
interfragmentary motion across the fracture site when actively using the skeletal structure With true rigid fixation, direct (primary) bone healing occurs (i.e., without callus formation).

Question 20

What are the goals of open reduction and internal rigid fixation?

Answer 20

● Accurate anatomical reduction
● Atraumatic operative technique preserving the viability of
bone and soft tissue
● Rigid internal fixation that produces a mechanically stable
skeletal unit allowing for early, active, and pain-free mobilization of the skeletal unit

Question 21

Define nonrigid fixation.

Answer 21

Any form of fixation that permits interfragmentary movement Healing occurs from indirect (secondary) bone healing, which occurs via formation of a subperiosteal callus.