Fijación interna Flashcards
Fijaciones internas
- Clavos intramedulares y agujas
- Clavos cerrojados
- Alambre ortopédico
- Bandas de tensión
- Placas y tornillos
Clavos intramedurales y agujas
Para fracturas de diafisis
Contraindicada en RADIUS
- Resistance to applied bending loads
- Poor resistance to axial (compressive) or rotacional loads. => add ceclaje wire and external fixator o plate)
> 2,5 mm = clavo
< 2,5 mm = aguja
Steinmann pins or Kirschner wires
Para fracturas de metafisis y epifisis
Clavos intramedulares y agujas
Key concepts in applying intramedullary pins
Retrograde o normograde ?
- Select a pin sized 60-70% of the medullary canal width to pair with cerclage wire
- Pin 50-60% of the medullary canal to pair with external fixator
- 40-50% if paired with a plate
- Span the length of the bone
- Always use additional fixation to control rotation and axial loading
Humerus/femur = retro/normograde | tibia = normograde!
Clavos cerrajados
- Interlocking nails are inserted in the medullary canal and locked in place with screws
- Use for middiaphyseal humeral, femoral o tibial fractures
- contraindicada en radius!!
- 2 screw on each side minimum, at 2 cm at least from the fracture line
Clavos cerrajados
Key concepts in applying interlocking Nails
- Use the largest nail that fits in the bone
- Span the length of the bone with the nail
- Ream the medullary canal with a Steinmann pin or use the reamers
- Insert the nail in a normograde fashion
- Position the nail so the holes are 2cm away from the fracture
- Secure the nail with four screws or fixation bolts for optimal fixation
Alambre ortopédico
- In combination with orther orthopedic implants to supplement, axial, rotational, bending support
- Cerclage wire -> around the bone
- Hemicerclage -> throught predrilled holes
- Most commonly used and misuded
Stabilizer need sufficient compression
* lenght of the fracture x2-3 the diameter of the marrow cavity
* max 3 fragments (2 ideal)
* anatomically reduced
Alambre ortopédico
Key concepts
- 2/3 wires / fracture lines
- perpendicular
- 0,5-1 bone diameter apart
- Support cerclage wires with an IM pin, interlocking nail, external fixator or plate
Bandas de tension
- Tension is the predominant force when avulsion fractures occur at a point where groups of muscles originate or insert in the bone
- Trochanter mayor, olecrano, and supraglenoid tuberosity of scapulae
- Two kirschner wires parallel to each other and perpendicular to the fracture
- Hole below the fracture as the same distance as head of the wires. Alambre entre los dos
Tornillos y placas
Generalidades
- Often used for fracture of the axial skeleton and are imperative for fractures involving joint surfaces.
- Tornillo : reconstruct aricular fractures without plate support in some cases
- Susceptible to repeated bending stresses : Implant fatigue failure occurs when the opposite cortex is not reconstructed.
- Locking screw plate systems»_space;>conventional plase system
Tornillo de tracción o compresión
Key concept in applying
- Reduce and secure the fracture before placing the lag screw
- For optimal compression, place the screw perpendicular to the fracture
- Drill the near cortex with a bit equal to the screw core diameter
- Dril the far cortex with a bit equal to the screw core diameter
- When using partially treaded screw, be sure the treads do not cross the fracture
tornillo cortical pas de vis petit et peu profond par rapport tornillo de medulla
Tornillo de posición
Placas de compresión dinamica, DCP / LC-DCP
Lock LCP / Unilock
LCP menos traumatica que DCP
