Hybrid Fixator—Proximal Tibia Frame
Synthes
Hybrid Fixator—Proximal Tibia Frame Technique Guide
When to use
The hybrid frame is used for the stabilization of complex
proximal tibial fractures, particularly those involving the joint.
Wire positioning
Proper wire positioning follows these basic guidelines:
– Use a minimum of two wires with a separating angle of
at least 60°.
1
Ideally, the wires should intersect at the
center of the bone.
– Wires may be positioned at different levels using the
Adjustable Wire/Pin Clamp.
– An adequate incision should be made at wire and Schanz
screw insertion points to avoid skin tenting and soft tissue
irritation. Wires should be straight for the same reason.
– An additional Schanz screw or third wire is placed in the
proximal fragment for stability. If a Schanz screw is used,
it should be placed below the ring and angled proximally
to maximize thread purchase in the bone.
– Position wires within the zone for safe pin placement
(note the location of the peroneal nerve).
– Place wires distal to the capsular attachment of the knee
joint. The capsular attachment is approximately 14 mm
below the plateau surface.
2,3
– When wires are placed near the proximal tibiofibular joint,
the safe distance from the knee joint must be carefully
evaluated because a torn septum may render this area
intra-articular.
4
This is of special concern when a wire is
placed through the fibular head, as in Figure 3 which
illustrates alternative wire placement.
– Generally, wires should be placed distal to cannulated
screws.
A
C
B
Figure 1
Typical wire positions with insertion sequence,
as noted on diagram:
A. Posterolateral to anteromedial tibia
B. Posteromedial to anterolateral tibia
C. Optional third wire, lateral to medial
1. F.J. Kummer. “Biomechanics of the Ilizarov External Fixator.”
Clinical Orthopaedics and Related Research
. 1992;280. 11–14.
2. T.A. DeCoster, M.K. Crawford and M.A. Steven Kraut. “Safe Extracapsular
Placement of Proximal Tibia Transfixion Pins.”
Journal of Orthopaedic Trauma.
1999;13;4. 236–240.
3. J.S. Reid, M.A. Vanslyke, M.J.R. Moulton, and T.A. Mann. “Safe Placement
of Proximal Tibial Transfixation Wires with Respect to Intracapsular Penetration.”
Journal of Orthopaedic Trauma.
2001;15;1. 10–17.
4. Ibid.
5. J. Geller, P. Tornetta III, D. Tiburzi, F. Kummer, and K. Koval. “Tension Wire
Position for Hybrid External Fixation of the Proximal Tibia.”
Journal of
Orthopaedic Trauma.
2000;14;7. 502–504.
A
C
B
14 mm
Most proximal
level of wire
Level of cross
section in
Figures 1 and 3
Figure 3
Alternative wire position, recommended for smaller fragments: Both
wires A and B can be inserted from a more posterior point, with A
traversing the fibular head. Insertion of wire C remains in the coronal
plane. Wires A and B exit more anteriorly than in typical configuration
(Figure 1) and all three wires create a triangle about the geographic
center of the proximal tibia. This configuration increases bending stiff-
ness in the AP plane and thus better resists displacement forces.
5
Most proximal
level of wire
Level of cross section
in Figures 1 and 3
14 mm
Figure 2
