A Study Protocol for a Randomised Controlled Trial Evaluating the Effects of Intraoperative Computed Tomography on the Outcomes of Zygomatic Fractures

Abstract

Background Zygomaticomaxillary complex (ZMC) and zygomatic arch (ZA) fractures are common injuries resulting from facial trauma and frequently require surgical management.1 A substantial number of post-operative functional and cosmetic complications can arise from the surgical management of these fractures. These include scarring, inadequate facial profile restoration, facial asymmetries and diplopia.2-4 Intuitively, most of these aforementioned complications arise as a result of inadequate fracture reduction, however current standard practice is to assess reduction post-operatively through plain radiographs or computed tomography (CT) scans. The role of intra-operative computed tomography (CT) scanning to assess the reduction of ZMC/ZA fractures and the potential impact on complications, has thus far not been established. Methods This is a prospective randomised controlled trial currently being undertaken at the Royal Brisbane and Women’s Hospital. All patients who require operative management of their ZMC or ZA fractures are offered enrollment in the trial. The patients are randomised into two groups: interventional (intra-operative CT) and control (no intra-operative CT). All patients from both groups will have post-operative radiographs taken. From these radiographs, the reduction of the ZMC and/or ZA fracture is graded by a blinded assessor. Patients will be reviewed in clinic at one and six weeks post-surgery. During these consultations, all patients will be assessed for scarring, diplopia, facial profile restoration and need for revision surgery. Discussion Many complications associated with surgical management of ZMC and ZA fractures involve poor aesthetic results as a direct consequence of inadequate fracture reduction. Inadequate fracture reduction is predictable given that small incisions are used and only limited visualisation of the fractures is possible during the procedure. This is due to a desire to limit scarring and reduce the risk of damage to vital structures in an aesthetically sensitive region of the body. It follows that an intraoperative adjunctive tool such as a CT scan, which can assist in visualisation of the fractures and the subsequent reduction, could potentially improve reduction and reduce complications.

Tratamento cirúrgico de fratura do complexo zigomático orbitário: Relato de caso

“…A intervenção em fraturas do CZO requer a análise do nível de deslocamento da fratura e os prováveis fragmentos da mesma, pois são condições relevantes para decidir se o tratamento será aberto ou fechado. Normalmente, é necessária a redução e fixação interna no tratamento aberto, sendo esta redução tempo-dependente e as vezes complicada de se conseguir devido a sua alta capacidade de produção de tecido cicatricial osteóide, especialmente nas fraturas cominutivas, por conta da complexidade do CZO, e se a cirurgia não for executada corretamente, a assimetria facial ficará evidente (Bao et al, 2019;Higgins et al, 2019). Fraturas que acometem o complexo zigomático e orbita, é possível uma apropriada redução e fixação em até 21 dias depois do trauma.…”

Use of ultrasonography in reduction of isolated zygomatic arch fracture

“…Inadequate reduction, if occur, is only visible in post-operative X-rays one day later thus requiring re operation for correcting inadequate treatment. Various methods like Intraoperative radiographs, 5 C arm 2 devices are used to confirm the adequate reduction but these procedure has radiation hazards. Portable Ultrasound (USG) machine are easily available and can be used intraoperatively without any radiological hazard to operator and to patient.…”

On the treatment of zygomaticomaxillary complex fractures

“…No time-delay between patient presentation and treatment is needed for computer-assisted surgical planning and the total extra timeinvestment is smaller. Intraoperative CBCT imaging in other specialties Intraoperative CBCT imaging is also used in fractures of the extremities [38][39][40][41][42][43][44] . Reported rates of direct revisions after intraoperative imaging vary between the different studies.…”

“…A systematic review on the use of intraoperative 3D imaging in fractures of the upper and lower extremities reports an 11-40% revision rate 44 . Especially in intra-articular fractures 3D imaging can prevent the occurrence of irregularities or steps on the articular surface 38,45 . The reported extra operating time spent for performing the CBCT-scan and evaluation of the images ranges from 5.3 to 10.2 minutes 41,42,46…”

“…In my view this is a study-power issue that could possibly be resolved by studies with more patients. A randomised controlled trial on intraoperative imaging in ZMC fractures has been announced in New-Zealand 38 . Unfortunately no objective measurement of ZMC fracture reduction is intended by the investigators, but it will be interesting to see their results on clinical parameters such as facial profile restauration and need for revision surgery.…”