1 Principles topenlarge
Definition: T-type fracture
T-fractures, though relatively uncommon, present unique surgical challenges.
This pattern combines a transverse component with a stem which exits either through the obturator ring or – in unusual cases – at various levels through the ischium.
Fractures in this group may also include a posterior wall component.
In contrast to the pure transverse fracture, the posterior and anterior column fractures frequently do not share a common orientation.
Choice of surgical approach
Factors which must be considered when making the approach choice are:
Level of anterior and posterior column fractures, i.e. transtectal, juxtatectal, or infratectal
Relative column displacement
Presence and configuration of posterior wall involvement
Associated marginal impaction
The majority of fracture patterns have predominant posterior column displacement and therefore can be operated through a Kocher-Langenbeck approach.
In cases where there is significant displacement of both columns the decision must be made whether to use a sequential ilioinguinal / Kocher-Langenbeck, or an extended iliofemoral approach.
An alternative to the extended iliofemoral approach for complex patterns in older patients would be the Kocher-Langenbeck with digastric trochanteric osteotomy (trochanteric flip extension). This approach can be used with or without true surgical dislocation. However, this alternative should not be considered in any way less demanding than the extended iliofemoral.
2 Cleaning of the fracture site top
Increase the displacement
Fracture sites are prepared by preliminarily increasing the displacement and then removing early callus and granulation tissue.
A Schanz screw placed in the ischium is one of the key manipulation aids for these maneuvres.
Joint distraction is extremely useful to facilitate this debridement.
Loose bodies and marginal impaction
Loose body removal is usually possible with joint distraction alone, particularly when combined with hip flexion on a fracture table. Rarely when a fragment is incarcerated in the anterior aspect of the joint it may be necessary to dislocate the femoral head to gain access for removal.
Large osteochondral loose bodies are placed in a saline bath until a decision can be made whether they can be replaced as part of the reconstruction.
Areas of marginal impaction are usually addressed after the columns have been reduced unless they impede the reduction.
3 Posterior column: Reduction topenlarge
Place a Schanz screw in the ischium
In the majority of T-type fractures, the posterior column is addressed first.
Control of the posterior column is facilitated by placement of a joystick in the ischium. This allows gross control of rotation around the stem of the T-fracture.
Assessment of reduction requires both visual assessment of the joint surface and digital palpation of the reduction, medially, on the quadrilateral surface.
Final assessment of reduction is also augmented by intraoperative fluoroscopy.
Specific reduction tools
Pointed reduction forceps
Pointed reduction forceps are applied on the posterior column across the fracture line. Drill holes in the bone may increase clamp security.
Quad clamp or Weber clamp
The distal end of a pointed reduction or a Quad clamp can be applied onto the quadrilateral surface through the greater sciatic notch. This also compresses the posterior column fracture, and may help close a medial gap.
A Farabeuf clamp, applied to screws in proximal and distal fragments, is shown reducing the posterior column fracture.
A small Jungbluth clamp, applied to screws in proximal and distal posterior column fragments, can also be used.
Plate reduction techniques
A small or mini fragment reconstruction plate which spans the posterior column adjacent to the greater sciatic notch is fixed distally with a single screw.
This acts as a reduction aid analogous to a clamp placed through the greater sciatic notch.
When the screw attaching the plate to the distal fragment is tightened, pressure of the plate on the proximal fragment reduces the anteriorly displaced distal fragment.
Note: Protect the sciatic nerve
It is frequently necessary to combine reduction techniques to achieve optimum reduction.
Protection of the sciatic nerve while working in the greater sciatic notch is critical. Hip extension and knee flexion decrease sciatic nerve tension and thus improve its mobility.
4 Posterior column: Fixation topenlarge
Preliminary fixation with screws
When the posterior column orientation permits, preliminary fixation is achieved with lag or position screws.
In some cases these screws can be placed through the primary surgical exposure. In others, a percutaneous route is required.
Virtually all acetabular fractures can be addressed with 3.5 mm screws and plate fixation. The inserted materials/implants should be 3.16 stainless steel in the pelvic reduction and fixation procedure.
Preliminary plate fixation
When screw fixation is impossible, then preliminary fixation is achieved with a small reconstruction plate along the greater sciatic notch.
Definitive plate fixation
Fixation of the posterior column is completed using a pelvic reconstruction plate which spans from the ischium to the supra-acetabular area. The contouring of this plate is critical since it must exert some compression on the anterior aspect of the posterior column fracture.
Patterns involving the posterior wall require definitive reduction of the wall fragments before application of this plate. Techniques for management of posterior wall fractures are discussed here.
Reduction and fixation of the posterior wall is generally the last component of the reconstruction.
Posterior column fixation implants must be placed in locations that do not prevent anterior column reduction.
5 Anterior column: Reduction topenlarge
In cases where the anterior column displacement is infratectal and there is no danger of secondary joint impingement it may be unnecessary to address the anterior column at all.
Anterior column fractures with important articular involvement but minimal displacement can usually be managed by lag screw fixation in situ alone. These screws must often be placed percutaneously to obtain access to the optimal insertion site.
This judgement is generally made preoperatively on the basis of imaging studies since access to the anterior column through the Kocher-Langenbeck without surgical dislocation is very limited.
When anterior column displacement is large, particularly when the fracture line significantly involves the weight-bearing dome, or if surgery is delayed, the extended iliofemoral approach may be required for reduction. It may simplify anterior column fixation as well. However, the additional dissection and slow rehabilitation are the clinical costs of this approach.
Additional posterior clamp placement
Should the anterior fracture gape on the quadrilateral surface, an additional clamp placed from posterior may correct this displacement. This image shows a quadrangular -or asymmetric pelvic reduction- clamp.
Accuracy of reduction must be verified by direct articular visualization.
This picture shows a Weber clamp, applied from posteriorly, as another supplementary option for anterior column reduction.
6 Anterior column: Fixation topenlarge
Fixation of the anterior column
Anterior column fixation consists of position or lag screws in all cases except for those managed with sequential posterior/anterior or anterior/posterior approaches.
The starting point for these screws is in an area of the innominate bone 2-3 cm cranial to the joint margin along the posterior margin of the gluteus medius pillar. Care must be taken to insure that lag screws are inserted perpendicular to the anterior column primary fracture plane. Secondary displacement will occur with screw tightening when this is not achieved.
In some cases placement of a position screw, after reduction and clamp compression, is a more prudent choice.
Alternative: anterior column fixation through ilioinguinal approach
A first-stage ilioinguinal approach might be considered for sequential
reduction and fixation, with the posterior portion of the fracture addressed
through a second-stage Kocher-Langenbeck incision.
When the ilioinguinal approach is performed first, care must be taken that plate fixation screws do not prevent subsequent posterior column or posterior wall reduction.