Open reduction in trapdoor-type blowout fractures using absorbable mesh plates

In many cases of trapdoor-type orbital blowout fracture, the bony segment has a stable hinge consisting of a greenstick fracture and the sinus mucoperiosteum that is attached to the intact orbital wall. If the displaced bony segment opposite the hinge will be reduced into its original position and will be fixed onto the unaffected bone, the orbital fracture may be reconstructed via the internal fixation of the bony segment itself rather than requiring substitution with an alloplastic implant or a bone graft.

A retrospective study was conducted from January 2008 to February 2010 in 34 patients with blowout fracture, via retrospective chart review, including detailed preoperative and postoperative evaluations, age, sex, symptoms, and signs, and based on the postoperative complications. The subciliary, transconjunctival, and transcaruncular approaches were used to expose the orbital floor under general anesthesia. The herniated orbital soft tissue was carefully reduced. The displaced bony segment was carefully pulled up and placed in its original anatomic position with a skin hook. A small absorbable mesh plate was inserted between the normal orbital wall and the bony segment, tangential to the edge of the bony defect at the dependent portion.

Postoperative examinations such as the traction and forced duction tests showed no eye movement limitation and surgical complications. During the follow-up period, no complications occurred, and the orbital wall was accurately reconstructed in its original anatomic position, as confirmed by postoperative computed tomography scans.

The advantages of internal fixation include anatomic reconstruction of the orbital wall, preservation of the original orbital bone and the mucoperiosteum of the sinus resulting in rapid wound healing and normal mucus drainage function of the sinus, simplicity of the procedure, and the absence of surgery-related complications. This technique is presented as one of the preferred treatments for trapdoor-type orbital blowout fracture.