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Page 10 of 13 Bradley et al. Plast Aesthet Res 2019;6:11 I http://dx.doi.org/10.20517/2347-9264.2019.06

orbital floor exploration was lower in comparison to a study of 72 patients with ZMC fractures, where 30%
of patients underwent orbital floor exploration . Some centres carry out orbital floor exploration in cases
[16]
of primary diplopia or evidence of comminuted ZMC fractures only . Interestingly, as demonstrated in
[17]
a survey involving facial reconstructive surgeons, it was shown that 35% would carry out an orbital floor
exploration routinely . The proportion of patients in our cohort undergoing orbital floor repair was also
[15]
lower when comparing to the literature. In a study of 758 patients with ZMC fractures, where intraoperative
CT imaging was used, 40% of patients underwent orbital floor repair, compared to 7.5% in our cohort,
although intraoperative CT imaging is not used in our centre for ZMC fracture fixation . Overall, these
[18]
comparisons highlight the ongoing lack of consensus regarding the management of orbital floor defects in
association with ZMC fractures.

Anatomically, although ZMC fractures will result in an orbital floor defect to a certain degree, not all cases
warrant surgical exploration or repair of the orbital floor . Orbital floor exploration and/or repair is often
[18]
required in the presences of eye signs (enopthalmus, hypoglobus, diplopia, restricted eye movements) or
a significant defect with or without ocular muscular entrapment seen on CT imaging. At present, aside
from clinical judgment based on examination and imaging, there is no clear consensus or guideline to
determine which cases of ZMC fractures require orbital floor exploration or repair. Further investigation to
compare pre-operative clinical eye signs in ZMC fractures (enopthalmus, hypoglobus, diplopia, restricted
eye movements), pre-operative orbital floor CT imaging, and the frequency of subsequent orbital floor
exploration and repair between different centres would be useful to aid developing such a protocol.

Of the 39 cases that underwent ORIF, one-point fixations were the most popular (54%, n = 21), followed
by two-point fixations (26%, n = 10) and three-point fixations (20%, n = 8). Amongst the cases of one-point
fixation, 90% (n = 19) had fixation at the ZM buttress, 5% (n = 1) at the FZ suture and 5% (n = 1) at the
IOM. Some literature supports the ZM buttress as the first choice for one-point fixations, with it providing
sufficient stability, without the need for fixation at the FZ site, whilst some studies advocate FZ suture as the
first choice, claiming that greater stability and immobilisation can be achieved at the FZ suture [4,11,13,19,20] . Of
note, none of the literature reviewed advocated the IOM as the first choice location for one-point fixation.

Our incidence of one-point fixations was 54%, which was higher compared to the literature, including
Covington et al. , who quoted that 30%-40% of ZMC fractures were adequately stabilised by one-point
[21]
fixations, and Ellis and Kittidumkerng , who quoted 31% [21,22] . A concern of one-point fixation can be
[22]
that the zygoma may not be sufficiently stabilized against the rotational forces from the masseter upon
mastication. In our cohort, there were no significant immediate or late post-operative complications, nor any
long term aesthetic concerns of the malar area. We can therefore deduce that 54% of our cohort underwent
successful ZMC stabilisation by one-point fixation. Of the two-point fixations, the most common sites of
fixation were ZM buttress and FZ suture (70%, n = 7), followed by ZM buttress and IO rim (30%, n = 3). This
was in keeping with a study of 210 surgically-managed ZMC fractures, in which similar anatomical locations
for two-point fixations were used .
[4]
All ZM buttress fixations in our cohort were accessed via an intraoral buccal sulcus incision, which was in
keeping with the literature . Given that this approach is intraoral, it has the advantage of avoiding any
[4,9]
external facial scarring . For FZ access (n = 16), upper blepharoplasty incision (56%, n = 9) was the most
[23]
common, followed by lateral eyebrow (31%, n = 5) and 2 cases through an old scar or current laceration (13%,
n= 2). For IOM access (n = 12), the most common incision was transconjunctival incision (75%, n = 9), followed
by subciliary (17%, n = 2) and subtarsal (8%, n = 1). Some literature suggests that the incisions for infraorbital
or orbital floor access carried the most complications, such as a study conducted on 180 patients showing
complication rates of 1.5% and 14% for entropion in transconjunctival and subciliary incision, respectively,
and a 3.4% incidence of hypertrophic scarring with subtarsal incisions [12,18] . Furthermore, the author of the