Classic tenets of facial fracture management were challenged by the severe craniofacial blast trauma patient. In traditional management of acute facial fractures , there are two well established windows for open reduction internal fixation (ORIF). Upon initial presentation, without undo swelling or other injuries/issues which are contraindicating, the patient may be taken to the operating room before swelling sets in (within 48 h). A second timeframe, which is the most commonly used is to wait approximately one week after injury (swelling has largely dissipated). It became evident fairly quickly after the start of the Iraq/Afghanistan conflicts that the traditional time frames used for facial fracture ORIF could not be utilized due to tremendous edema within the craniofacial skeleton and the presence of multiple concomitant injuries. In reviewing our acute fracture cohort who had blast trauma, the average time to ORIF was approximately 21 days after injury. This finding was also corroborated in the extremity experience from blast casualties [5]. By this time point some of the swelling had diminished, but there was still persistent inflammation within the tissues that made accurate ORIF more challenging.

In addition to timing, the nature of fracture patterns, and accompanying soft tissue loss complicated the management of acute facial fractures . Given the high prevalence of blast injury and use of high caliber weaponry, many service members suffered complex fractures well beyond the traditional patterns seen in low caliber penetrating or blunt trauma. Bone was frequently devascularized, and rendered unusable in standard reduction/fixation techniques. Often, primary bone grafting was necessary to achieve a stable craniofacial skeleton. Attempts to use alloplastic materials in the maxillofacial skeleton were fraught with failure, most likely due to contact with sinus cavities and nasal flora. Moreover, these areas of complex fracture were compound in nature. With a composite tissue loss, free flap reconstruction brought vascularized tissue to protect and assist in healing of bone grafted regions.

Primary bone grafting and free flap reconstruction provided the foundation for treatment of acute maxillofacial fractures up to and including the orbital bandeau. Above the level of the bandeau, primary cranial reconstruction involved ORIF of fractures, soft tissue coverage with local or free flaps, and cranialization of the frontal sinus. Without stable soft tissue coverage and definitive separation of the nasal and brain cavities, successful secondary reconstruction of the cranium was plagued with failure.

Any reconstruction occurring outside of the acute/subacute window (>2 months) was defined as secondary reconstruction. Secondary facial reconstruction consisted of facial osteotomy and repositioning, bone grafting techniques, and free tissue transfer. Cranial reconstruction was typically performed in the secondary time frame; as swelling, limited soft tissue coverage, and frontal sinus injury prohibited definitive primary reconstruction.

Requirements for definitive cranial reconstruction included: cranialization of the frontal sinus (if primarily injured), good soft tissue coverage, and a 3-month infection-free healing period off antibiotics. (Table 27.1) For most patients this would fall around 6 months after initial trauma. Cranialization of the frontal sinus involved removal of the nasofrontal ducts, primary bone grafting (corticocancellous), with a pericranial flap. Many patients were so severely injured that this traditional method of cranialization was not feasible. With large defects free tissue transfer into the anterior cranial fossa was utilized to achieve craniofacial separation, with or without primary bone grafting. With regard to soft tissue coverage, many service members could be healed with wound care, others required local (rare) or free flap coverage to achieve a stable soft tissue envelope. In some cases tissue expansion of the scalp provided sufficient coverage for patients undergoing cranial reconstruction, which would overcome tight scarring and contracture. As mentioned earlier, contamination of penetrating wounds was a significant problem, especially with A. Baumanii. A protocol of 3 months of infection healing off antibiotics was developed to ward off long-term colonization/infection of alloplastic reconstructive materials.

While no ideal cranial implant material for large-scale reconstructions currently exists, there are several desirable characteristics. A custom shape is necessary which mirrors the missing segment of cranium. The material needs to be bone-like in its quality. It should have long-term sustainability, i.e., present for long-term brain protection and contour. Even with advanced imaging technology and software which produces a 3D patient-specific prefabricated design, there can be small discrepancies at the time of implantation, such as bone differences or scarring which prevent a native implant from fitting perfectly. In this scenario, implant contouring is required to allow proper fit. Biocompatibility and biointegration is desirable, to reduce long-term risk of infection and/or exposure.