4.1 Access

The choice of operative approach for delayed reconstruction largely depends on the specific fracture patterns involved. Anterior column and wall fractures may be stabilized through the ilioinguinal approach even after significant delays. Similarly, the Kocher-Langenbeck approach for isolated posterior column or wall fractures may also provide sufficient exposure, even with prolonged delays in treatment. Use of these incisions for more complex associated fracture patterns may compromise the ability to completely mobilize and reduce all fracture lines. The extended iliofemoral approach of Letournel is often necessary to achieve fracture reduction after significant delay in treatment. Double exposures (ie, the Kocher-Langenbeck and ilioinguinal approaches) are infrequently used and generally have been abandoned after experience showed that the extended iliofemoral approach offered better access, a higher prevalence of anatomical reduction, and stable fixation of the acetabulum. The extended iliofemoral approach was not described until 1974 by Letournel and Judet [10] and since then it has been used more often in delayed surgical reconstruction, especially in both-column fractures [5, 6]. Both anterior and posterior components of the acetabular fracture can often be controlled using this approach and both the external and internal aspects of the iliac wing are exposed. The digastric trochanteric flip osteotomy of Ganz may offer a different approach to delayed fracture management. This approach exposes the central roof acetabular articular cartilage and impacted roof injuries, as well as T-type, high-transverse and lateral roof fractures [12, 13]. Surgical dislocation is also possible with this approach, and allows increased visualization of intraarticular pathology.

4.2 Instruments and implants

Pelvic instruments and implants from specialized instruments sets constitute most of the equipment needed to perform this surgery. Specialized pelvic forceps and tongs with ball-tipped spikes with washers are a necessity. These forceps are in various shapes and sizes with asymmetrical clamp jaws and variable lengths to allow placement specifically around corners and under soft-tissue barriers to facilitate fragment reduction. An oscillating saw with a choice of blades, chisels of different widths, variable action fracture distractors, and an array of osteotomes offer additional reduction aids for difficult reduction of displaced fragments. Spinal rongeurs may also be helpful for removal of callus around neurovascular structures.

4.3 Reduction

Reduction techniques for delayed acetabular fracture surgery require extensive surgical experience and knowledge of approaches, familiarity with reduction techniques, and ability to apply appropriate stable fixation. Simple fracture patterns (ie, anterior wall, anterior column, posterior wall, posterior column, and some transverse fractures) generally are managed through a direct exposure, using either the ilioinguinal or Kocher-Langenbeck approaches. If fracture lines are visible and no significant callus formation has occurred, the techniques of fragment debridement and reduction and compression of major fracture lines with appropriate internal fixation are no different from surgery performed within 3 weeks of injury. The fragment surfaces are debrided of scar and new callus formation to facilitate anatomical reduction. Every effort should be made to preserve as much soft tissue and blood supply to these fragments. Capsulotomy to visualize the articular surface is helpful in assessing the reduction. The fracture surfaces are more irregular and difficult to position anatomically but once the appropriate reduction is achieved, a standard osteosynthesis is performed. In patients with fracture nonunion or malunion, the fibrous tissue is excised or the fragment osteotomized to allow reconstruction. Fractures lines will still be present in the articular cartilage, even though they are indistinguishable on the cortical bone surface. An osteotomy through the articular surface, followed by resection of the intervening wedge of bone may be necessary to correctly reposition the fracture fragments. Transverse fractures may develop malunion at the anterior fracture line and nonunion at the posterior fragment surface. A combination of resection of the posterior scar tissue and osteotomy of the anterior malunion is required in this situation. Multiple trial reductions may be required to align the fragments into anatomical position. Intraoperative x-rays may be necessary to evaluate reduction before completion of the osteosynthesis.

Femoral head dislocation or subluxation associated with posterior wall fragments may be especially difficult to mobilize. Isolated posterior wall fracture dislocation may also present difficulty in determining what is malunion bone and where the wall fragment cortical margin begins. These wall fragments must be separated from new callus formation, free of associated fibrous tissue, and an attempt must be made to preserve capsular soft-tissue attachments to maintain viability of the wall fragments. Difficulty arises with small or multiple wall fragments, in which case stabilization with lag screw fixation is not an option. Stabilization of small wall fragments with multiple lag screws is associated with a high prevalence of intraarticular screw penetration. These fragments may need to be stabilized with “spring plates” reinforced with conventional reconstruction plates 3.5 [14]. Anterior release of contracted capsule or muscle attachments may also be necessary to maintain a concentric reduction and reduce both the tendency for redislocation and the abnormal stress concentration to the femoral head from the posterior wall reconstruction. Anatomical reduction of fracture lines is the goal but may be difficult to achieve due to erosion or reabsorption of fracture lines and loss of recognizable reduction markers.