12.5  Craniofrontal Fractures (CCF)

•Orbito-cranial injuries with

––Involvement of the orbital roof

––Orbito-frontal perforations

––Extensive lateral orbital roof fractures and cerebral or dural injuries

•Isolated, dislocated orbital roof fractures (no fractures of the skull bone)

•Traumatic optical nerve injuries or compression of the optic nerve due to fractures of the sphenoid bone (decompression!) (Fig. 12.25–12.30)

Reconstructive sequence (Samii and Draf 1989; Weerda 1995)

•Transfrontal exposure of the orbito-temporo- cranial region using the coronal approach with pre-auricular extension possibly in combination with transfacial incisions

•Subperiosteal exposure of the zygomatico-orbital and temporal complex by intrafascial preparation with possible lateralization of the temporal muscle

•Fragment elevation and selective osteoplastic temporal craniotomy and treatment of cerebraldural and orbital injuries

•Reduction and osteosynthesis of the zygomatic arch and the zygomatico-orbital complex; reconstruction of the orbital roof and supraorbital margin as well as the periorbital osseous frame

•Reduction and osteosynthesis of accompanying maxillary/naso-ethmoidal fractures

•Reconstruction of the orbital walls with autogenous bone grafts or resorbable membranes; refixation of the medial/lateral canthal ligaments

12.5  Craniofrontal Fractures (CCF)

In this fracture class, the following fracture subtypes are listed according to the extent of the fracture (Donald 1986, 1998a, b; Duvall et al. 1987; Wolfe and Johnson 1988; Stanley 1989):

•Frontal sinus fractures (isolated)

•Frontal sinus-ethmoidal fractures

•Frontal sinus-orbital-ethmoidal fractures

•Combined fractures

Fractures of the craniofrontal region comprise about 5% of all fractures in the facial region and 2–12% of all cranial fractures (Ioannides et al. 1993).

There may either be isolated or combined fractures of the anterior and posterior walls of the frontal sinus.

As the bone lamellae of the posterior wall are considerably thinner than those of the anterior wall, frontal impact vectors may result in isolated fracture of the posterior wall caused by lateral tension during skull deformation (Hybels 1977).

12.5.1  Concept of Reconstruction

The reconstructive concept is orientated according to fracture extent of the ventral and dorsal frontal sinus walls (types I–III/Godbersen and Kügelgen 1998) as well as the condition and involvement of the ethmoidal infundibulum and the skull base (Levine et al. 1986; Luce 1987; Stanley 1989; Godbersen and Kügelgen 1998; Mathog 1992; Baker et al. 2003).

•Type-I fractures (ventral sinus wall fractures): no concomitant fractures exist. In such cases, no ethmoidal cell debridement is necessary.

•Type-II fractures (ventral and dorsal sinus wall fractures): the dorsal wall of the frontal sinus and the ethmoid region must always be examined to exclude dural injuries. In case of doubt, liquormarking with fluorescein should be undertaken.

•Type-III fractures are easily recognized, either by rhinoliquorrhea or cerebral prolapse with evidence of dural injury. The more extended the fractures (orbit and midface fractures), the higher the probability of dural injury (Godbersen and Kügelgen 1998).

The principle aim is to reconstruct the frontal sinus (Ehrenfeld et al. 1996; Ernst et al. 2004). Cranialization of the frontal sinus is indicated in comminuted fractures of the posterior sinus wall.

Reconstructive sequence (Baker et al. 2003)

•Transfrontal or transfacial exposure of the frontal region

•Fragment elevation and treatment of cerebral and dural injuries (cranialization of the frontal sinus, if necessary)

•Reconstruction of the anterior wall of the frontal sinus using local bone or autogenous bone grafts (Donald 1986; Ellis 1993). Reconstruction of the anterior wall of the frontal sinus with titanium mesh in case of multiple fractures

Fig. 12.27  Cranio-orbito-zygomatic-fracture (COF/cranio-orb- ito-facial fracture). (a) Preoperative CT-scan demonstrating severe displacement of the orbital walls and NOE complex. (b)

Intraoperative view demonstrating comminution of the left lateral orbit. (c) Intraoperative view after craniotomy, dural repair and reconstruction of the zygomatico-orbital complex

Fig. 12.28  Zygomatico-orbito-cranial fracture with dorsal sinus wall fracture and prolapse of brain tissue (COF). (a) Osteoplastic craniotomy, base exposure and removal of the dorsal sinus wall, intracavital brain tissue prolapse (arrow). (b)

Reintegration of the bone flap following treatment of the cerebral and dural injuries and reconstruction of the frontofacial and zygomatico-temporal region

Fig. 12.29  Depressed cranio-orbital fracture with orbital roof fracture (COF). (a) Status following osteoplastic, unilateral craniotomy and exposure of the fractured orbital roof (arrow). (b)

Status following orbital roof reconstruction and supraorbital contour restauration. (c) Reintegration of the pre-fixed osteoplastic bone fragments and filling the craniotomy holes with bone dust

A transfrontal approach is indicated in the following central fronto-cranial injuries:

•Dislocated fractures of anterior and posterior walls of the frontal sinus, limited injuries to the cribriform plate and the medial orbital roof with and without evidence of liquorrhea

•Dislocated fractures of the fronto-orbital complex with contour irregularity, globe displacement and disturbances of eye motility

•Fractures of the fronto-orbital complex with traumatic bone loss of the supraorbital frontal region and the orbital roof

The surgical approach depends on the extent of anterior wall fracture as well as the degree of dislocation. Either a transfacial or coronal approach is used (Bowles and Anand 1998).

•For anterior wall fractures with minimal to modest degree of dislocation without significant injury to the mucous membranes and intact infundibulum, the fronto-orbital (transfacial) approach may be the one of choice (Theissing 1996; Lappert and Lee 1998).

After exposing the fractures, the impressed anterior wall fragments are raised or temporarily removed (Merville

Fig. 12.30  Cranio-orbital fracture (COF). (a–d) Preoperative CT-scan demonstrating depressed comminuted fractures of the fronto-temporal bone and frontal skull base and the orbital roof. (e–f) Intraoperative situation after reconstruction of the frontal skull base, dural repair, cranialization of the frontal sinus,

insertion­ of a pericranial flap and fixation of the frontal bone fragments. g–i Postoperative situation after frontal craniotomy and cranialization of the frontal sinus and reduction and fixation of the cranial fragments with multiple 2.0 mm miniplates

et al. 1983; Mathog 1984; Hoffman and Krause 1991). Small bony fragments, foreign bodies and lacerated portions of the mucous membrane are carefully removed from the frontal sinus. The posterior wall of the frontal sinus is carefully examined (endoscopically) for additional fractures. The patency of the nasofrontal duct is examined using methylene blue. All bony fragments are replaced in the exact anatomical position and fixed with minior microplates (Prein 1998). Even small fragments can be used for reconstruction (Figs. 12.31–12.34).

Residual frontal defects, larger than 1 cm2 should be reconstructed. This can be carried out using autogenous bone grafts (calvarial grafts – tabula externa) or alternatively, in particular in anatomically difficult regions with titanium micromesh (Dempf et al. 1998;

Vesper et al. 1998; Deinsberger et al. 1998; Kuttenberger and Hardt 2001) (Fig. 12.35).

Disadvantages of the fronto-orbital approach are the limited surgical exposure and visible scars. Limited scars in the nasoorbital region can be concealed by the eyebrows and should be placed in natural skin lines.

•For extensive, depressed and comminuted fractures of the anterior wall of the frontal sinus the coronal approach is recommended.

In general, drains have to be placed in all fractures affecting the paranasal sinuses. In fractures involving the frontal sinus, sufficient ventilation and drainage can be achieved by resection of the interfrontal septum

and a high nasal septum. Intranasal drains can also be placed into the sinus through the frontal infundibulum (Richter 1992).

12.5.4  Fractures of the Posterior Frontal

Sinus Wall with Anterior Skull Base

Involvement

Small dural defects caused by fractures of the dorsal wall of the frontal sinus and dural defects at the junction to the ethmoid and cribriform plate can in some cases be directly occluded with sutures. Additional dural repair should be performed with autogenous fascial grafts or alloplastic dural substitutes (e.g., Neuropatch) (Ernst et al. 2004).

More extensive dural defects are closed with dural substitutes (e.g., Neuropatch, pericranial grafts, fascia lata) after the dura has been released from the bony margins.

All dural grafts and membranes are either fixed with sutures or fibrin glue (Stoll 1993; Ernst et al. 2004). After dural closure in selected cases the posterior sinus wall can be reconstructed using the bone fragments available (Hybels 1977; Elies 1982; Stoll 1993). If extensive dural injuries exist beyond the region of the frontal sinus (ethmoid, medial orbital roof) the transfrontal approach has to be used (Donald 1998a).

•In sinus wall fractures with additional frontal skull base injuries, the transfrontal approach with a tran- scranial-extradural or subcranial-subdural exposure is favored due to aesthetic and surgical reasons

Fig. 12.33  Anterior frontal sinus wall fracture with depressed fragments (CFF). (a) Exposure via coronal approach — fragment­ removal. (b) Examination of dorsal sinus wall and nasofrontal

duct. (c) Reconstruction starting from the fracture margin, stabilization with three-dimensional miniplates

Fig. 12.34  Comminuted anterior sinus wall fracture (CFF). (a) Comminuted anterior sinus wall (following transfacial fracture exposure/X-ray). (b) Removal of the bony fragments. (c)

Reduction and osteosynthesis of the anterior sinus wall (clinically/X-ray) with 1.5-mm miniplates. (d) Postoperative result (1 week/3 months postoperatively)