Trapdoor Fracture of the Orbit in a Pediatric Population

Abstract

Orbital-floor blowout fractures of the trapdoor variety, first described by Soll and Poley, have also appeared in the French and Japanese literature. The trapdoor fracture is described as a pure orbital-floor fracture, linear in form and hinged medially, which allows herniation of orbital contents through the fracture and then entraps these herniated contents. A review of the orbital-floor fracture literature reveals a high incidence of persistent diplopia associated with ocular-muscle entrapment, which may later necessitate corrective surgery of extraocular muscles. Recent publications in the ophthalmologic literature have stressed the importance of early surgical intervention. This article reports a retrospective series of 19 pediatric patients (age range, 5 to 16 years) who presented to two institutions. All patients had radiographic confirmation of a trapdoor fracture. Physical examination demonstrated a high association between these fractures and restricted ocular motility (17 of the 19 patients). In the cases with trapdoor fracture and restricted ocular movement, early intervention was associated with better postoperative function. It is thus recommended that the symptomatic trapdoor orbit fracture be considered an urgent indication for surgical intervention. Practitioners therefore must have a high index of suspicion for these injuries. Prompt diagnosis is critical to maximize clinical outcome.

Isolated orbital floor fractures in the paediatric patient: case series and review of management

“…Studies regarding the management of orbital floor trauma in the paediatric population remain limited, with only a few pertaining to orbital floor fractures involving operative managment. 6,[12][13][14] In a review of the literature, 15 significant differences were noted between paediatric and adult patients, which included the mode of clinical presentation, differing fracture patterns, and the need for earlier intervention in the symptomatic group, as well as the expectation of a slower and poorer outcome in paediatric orbital floor fractures. 6,16 It was generally recorded that surgical intervention rates increase with the age of the patient.…”

“…5,[12][13][14] It has been suggested that the timing of paediatric orbital surgery can be classified as immediate (0-48 h), early (3-14 days), and late (15 days or more), with a greater urgency for trapdoor fracture, 18 yet other authors have suggested that early surgery in the paediatric population may include up to several days post-injury. 21 While early treatment of a 'white-eye' orbital floor fracture may not be indicated from the clinical presentation alone, the radiological diagnosis of the trapdoor fracture with entrapped soft tissue/muscle contents may represent a surgical emergency requiring prompt management to avoid a poorer outcome if delayed beyond 48 h. 13,22 The unique nature of 'trapdoor' fractures 4 and the resulting entrapment of adjacent extraocular muscles is also thought to result in a degree of muscle compartment pressure and subsequently ischaemia, as has been described in orthopaedic injuries. 16 Without prompt intervention, muscle ischaemia and/or scarring of the adjacent tissues may lead to impaired ocular mobility with consequent diplopia.…”

“…6 Whatever the mechanism of soft tissue injury, early intervention is associated with a superior outcome in trapdoor fractures, 5,14,21 and surgery is therefore recommended within 2 days in this population. 13 It is possible that due to the rapid bone turnover in young patients, early callus formation may make surgical reduction more challenging and contribute to poorer outcomes. 24 A trans-conjunctival approach is the preferred access to the orbital floor, because the absence of any skin creases in young patients means alternative skin incisions for access are less desirable.…”

An Analysis of 733 Surgically Treated Blowout Fractures

“…Numerous studies have been performed on orbital fractures so far [1,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17]. However, much of the literature is either out of date or based on small groups of patients.…”

Orbital fractures in children: 10 years’ experience from a tertiary centre

“…The term "trapdoor" is used to describe this type of fracture. 23,24 In contrast, adults are more likely to have comminuted fractures, and orbital contents -if extruded -are less likely to be trapped. Entrapment of muscle associated with orbital fractures is rare, and we saw only one patient with entrapment of the inferior rectus muscle.…”