2. Principle
Based on the principle ‘’that growing bone
changes its form and volume according to
external stimuli’’ (Wolff’s law), Ilizarov
subjected bone to continual external
tension in any direction, which can
lengthen the bone or correct deformities.
3. His biological principles can be
summarized as:
• Minimal disturbance of bone and
• soft tissues
• Delay before distraction
• Rate and rhythm of distraction
• Site of lengthening
• Stable fixator of external fixator
• Functional use of limb and
• Intense physiotherapy
5. Assembly of circular fixator
• Major considerations-
– Stability of fixation of the frame to the bone.
– The prevention of gross bone fragment motion.
– Ability to manipulate bone and to perform necessary
fragment movement such as straightening, bending,
distraction, compression, rotation and combination of these
movement.
• Construction of frame can be done in advance or during surgery.
• Important aspect of frame assembly-
– Ring positioning
– Ring inclination
– Ring orientation
– Ring level
– Spacing between skin and ring
18. Prior to passing wire each muscle should
be stretched maximally to its functional
length to prevent contracture.
Wire is drilled through both the cortex,
passing through bony canal and bone
marrow trans medullary.
19. For stability 2 wire cross crossing at
an angle as close to 90* are required
20. Wire is close to ring connector, it bear small axial load
and when it is away from ring connector it bears
greater axial load
21. Adequate tension is paramount importance. Inadequate
tensioning adversely effect development.
• Range of wire tensioning- 50- 130kg.
• Tensioning strength of wire on half ring- 50-70kg.
• Tensioning strength of offsite wire- 50-80 kg.
• Tensioning strength of single wire on ring-100kg.
• Tensioning strength of 2-3 wires on ring in young patient – 110 kg each ring.
• Tensioning strength of 2-3 wires on ring in adult patient – 120-130 kg each ring
• Tensioning strength of wire with olive stopper- 100-110 kg.
22. Position of wire in relation to hole and
type of fixation part appropriate to
each situation.
23. Corticotomy
• It is low energy osteotomy of cortex preserving local
blood
• supply to both periosteum and medullary canal.
• Types- monofocal & bifocal
• Ideal corticotomy-
– Long oblique
– Metaphyseal in situation
– No comminution
– No disruption of endosteal & periosteal blood supply
– Fixed in anatomical position with gap <2mm
24. Complications
Early complication
• Vascular complications
• Neurological complications
• Comminuted fracture of osteotomized
bone
• Local skin tightness
• Psychologic incompatibility
Late complication
• Pin site infection
• Pain at corticotomy site and during
lengthening
• Soft tissue contractures and joint stiffness
• Osteoporosis
• Reflex sympathetic dystrophy
• Progression of angular deformity or creation
of new one after fixator removal.
• Limb swelling
• Nonunion or premature consolidation at
lengthening site
• Compartment syndrome
• Joint subluxation
26. Pin-site care
• Proper pin/wire insertion
• To prevent postoperative complications, pin/wire-insertion
technique is more important than any pin/wire-care protocol:
– Correct placement of pins/wires (see safe zones) avoiding
ligaments and tendons, eg tibia anterior
– Correct insertion of pins/wires (eg trajectory, depth)
avoiding heat necrosis
– Extending skin incisions to release soft-tissue tension
around the pin/wire insertion (see inspection and
treatment of skin incisions)
28. You can be taller even after 18 yrs with Ilizarov
Editor's Notes
Principles
As the ring fixator is an external fixator, it gives relative stability.
As pins are inserted across different planes in a multiplanar fixation, the construct provides great stability.
The stiffness of the construction can vary depending on the configuration of the fixation, the number of rings used, and usage of different types of pins such as K-wires or Schanz screws.
Depending on the assembly, the fracture can be distracted, or compressed, and deformities can be corrected.
A common use for the ring fixator is distraction osteogenesis to correct bone loss, shortening and deformity.
Indications
In fresh fractures, there are several indications for using a ring fixator:
Severe soft-tissue compromise
Multifragmentary fractures
Fractures of the proximal or distal diaphysis, possibly with extension into the metaphysis
Bone loss
Delayed presentation of the fracture (>3 weeks)
The peroneal nerve runs posteriorly at the level of the fibular head and curves anteriorly as it goes caudal.
Transfixation
The medial and the lateral zones at the level of and ventral to the fibular head are the only safe zones for tibial transfixation.
Unilateral fixation
The anterior zone on both sides of the patellar ligament is safe for unilateral fixation.
Distal to the tibial tuberosity only unilateral external fixation is safe.
It is best to insert the pins where soft-tissue coverage is minimal as the risk of pin track infection is lowest.
The neurovascular bundle with the anterior tibial artery and vein together with the deep peroneal nerve are running close to the posterolateral border of the tibia.
They are at risk if the pin is inserted in the way indicated by the red dotted line.
When inserting pins in the distal zone take into account the position of the anterior tibial artery and vein. Percutaneous insertion of pins in this area is dangerous. A minimal incision will allow preparation and safe insertion.
The peroneal bundle is located very close to the posterolateral border of the tibia and therefore at risk if pins are inserted in this direction.
Pins at this level should be inserted as shown in the illustration from anteromedial to posterolateral. A second pin can be inserted from medial to anterolateral, ventral to the fibula.
The proximal ring is placed at the level of the head of the fibula and parallel to the knee joint.
The first wire is inserted from posterolateral to anteromedial going through the fibular head.
A second wire should be inserted as perpendicularly as possible to the first one from anterior to posteromedial.
A third wire is inserted between these two.
Place the ring at the level of the proximal end of the syndesmosis.
The first K-wire is inserted from posterolateral to anteromedial through the fibula.
A second wire should be inserted as perpendicularly as possible to the first one from anterolateral to posteromedial.
A third wire is inserted between these two.
Add a second ring in the proximal fragment of the midshaft, connecting it with 4 rods to the proximal ring.
The distance of this third ring to the fracture will determine the working length. More length means more flexibility while a shorter length will give greater rigidity.
Insert 2 K-wires as perpendicular to each other as possible.
Note:
Using a Schanz screw will make the construct more rigid.
Add a second ring in the distal fragment of the midshaft, connecting it with 4 rods to the distal ring.
Again, the distance of this fourth ring to the fracture will determine the working length. More length means more flexibility while a shorter length will give greater rigidity.
Insert 2 K-wires as perpendicular to each other as possible.
Connect the two intermediate rings with 4 rods without completely tightening the bolts.
Reduce the fracture by manipulating the rings. When reduction has been achieved, tighten the bolts.
mmediate postoperative care
Immediately after surgery, while the patient is still in the hospital, emphasis is given to:
Pain control
Mobilization
Infection and deep veinous thrombosis (DVT) prophylaxis
Early recognition of complications
The patient’s leg should be slightly elevated, with the leg placed on a pillow, 4 cm above the level of the heart.
Advise the patient about foot positioning in order to avoid equinus deformity.
Various aftercare protocols to prevent pin tract infection have been established by experts worldwide. Therefore no standard protocol for pin-site care can be stated here. Nevertheless, the following points are recommended:
The aftercare should follow the same protocol until removal of the external fixator.
The pin/wire-insertion sites should be kept clean. Any crusts or exudates should be removed. The pins/wires may be cleaned with saline and/or disinfectant solution/alcohol. The frequency of cleaning depends on the circumstances and varies from daily to weekly but should be done in moderation.
No ointments or antibiotic solutions are recommended for routine pin-site care.
Dressings are not usually necessary once wound drainage has ceased.
Pin/wire-insertion sites need not be protected for showering or bathing with clean water.
The patient or the carer should learn and apply the cleaning routine.
Pin/wire loosening or pin tract infection
In case of pin/wire loosening or pin tract infection, the following steps need to be taken:
Remove all involved pins/wires and place new pins/wires in a healthy location.
Debride the pin sites in the operating theater, using curettage and irrigation.
Take specimens for a microbiological study to guide appropriate antibiotic treatment if necessary.
Before changing to a definitive internal fixation an infected pin tract needs to heal. Otherwise infection will result.
Partial weight-bearing with crutches should begin as soon as possible.
Depending on the consolidation, weight bearing can be increased after 6-8 weeks with full weight bearing when the fracture has healed.
