Comparative Study between Conchal Cartilage Grafts and Split Rib Grafts in the Reconstruction of Orbital Floor Fractures

INTRODUCTION
Orbital floor fractures are of the commonest
maxillofacial injuries nowadays due to increased
incidence of interpersonal violence and road traffic
accidents. As denoted by Chang and Manolidis,
Mackenzie was the first to describe orbital floor
fractures in 1844 [1]. Since then, various studies
have discussed the indications and most advantageous
time in which surgery should be considered
273
as well as the most considerable surgical modality
to be used for orbital blowout fractures.
Over a hundred years later, specifically in the
year 1957, Smith and Regan identified inferior
rectus muscle entrapment which resulted in diminished
ocular motility during orbital fractures and
named them “blow-out fractures” [2]. Since then,
multiple studies have researched the indications
and most appropriate timing for surgical intervention
in addition to the most favorable surgical
modality [3].
In order to use autografts, autologous patient
tissue must be available for harvest from a donor
site. It should be further shaped to perfectly match
the dimensions of the defect in order to provide
with structurally intact support for the underlying
tissues and structures. It is usually easier to harvest
cartilage and shape it, hence further contributes to
long-term support without resorption [4,5].
Autologous reconstruction of orbital floor by
cartilage grafts was used in different studies as
presented by Castellani et al., [6] and Ozayzgan et
al., [7].
However other previous studies have considered
bone grafts for the orbital floor as the recommended
management for orbital fracture. This approach is
based on the availability of adequate amount of
autologous bone obtained from a donor site. It has
to be further shaped and inserted in order to give
firm structural support in reestablishing the defect.
Being biocompatible, craniofacial surgeons have
favored bone grafts in management of such fractures.
Among the donor sites are the split calvarial
Bone Graft, rib, and iliac crest [8-10]. Grafts could
be either located as onlay Grafts [11], fixated with
a plate and screw [12], fixated with a lag screw or
fixated in conjunction with an alloplastic material,
such as titanium mesh or porous polyethylene
sheets [13-15]. There is no definite approval about
the suitable material for reconstruction.
The aim of this study is to compare the results
of using autologous cartilage graft with those of
split rib graft in small posttraumatic orbital floor
defects reconstruction.
PATIENTS AND METHODS
A randomized controlled comparative study
was conducted in the Plastic and Maxillofacial
Surgery Department at Ain shams University Hospitals.
The present study included 30 patients, 22
males and 8 females, with age ranging from 23-
49 years, average 36 years. They presented to the
outpatient and emergency room of the hospital
with orbital floor fractures along with floor defects
either isolated or with other maxillofacial fractures
from November 2014 to December 2016.
Patients were subdivided into two groups, 15
cases were managed using autologous cartilage
grafts for reconstruction of the orbital floor defects
either unilateral or sutured biconchal cartilage
grafts according to the size of the defect (Group
1) and 15 cases were managed using onlay split
rib graft (Group 2). The patients were selected
randomly irrespective of age and sex.
The following inclusion criteria were fulfilled:
(1) Clinical diagnosis of orbital floor defects; (2)
Computed Tomography (CT) showing orbital floor
defects; (3) Intraoperative finding of small orbital
floor defects £2cm2. Exclusion criteria include (1)
orbital floor fracture without bone defect or (2)
large defects >2cm2 or patients who had prior
surgery were excluded from the study.
History was recorded & full clinical examination
was performed including local & general
examinations. Local examination was done paying
special attention to the following: Restrained ocular
movement, ocular dystopia, enophthalos, diplopia
specifically on upward gaze, paresthesia in the
infraorbital nerve distribution and step deformity.
All patients were ophthalmologically examined on
admission, preoperatively, postoperatively after
the swelling had ceased, and during follow-up.
Any other injuries were recorded and assessed and
confirmed by related different specialties.
All patients had CT imaging with axial, coronal
and sagittal cuts and 3D image construction. Informed
consent was obtained from all patients. All
the patients had their operations under general
anesthesia. We used transconjunctival incision/
subciliary incisions in all cases. Greatest dimensions
274 Vol. 42, No. 2 / Comparative Study between Conchal Cartilage Grafts & Split Rib Grafts
of the defect are measured and according to the
size of the defect In Group 1, defects of orbital
floor were reconstructed by Conchal Cartilage
Grafts either unilateral (defect size up to 1.5cm2)
or sutured biconchal cartilage grafts (defect size
1.5-2cm2).
Conchal cartilage grafts were harvested through
anterior or posterior incision. Special care was in
concern during harvesting the graft to ensure the
integrity of the concha as monoblock aiming for
better occlusion of the floor.
In Group 2, similar defects were reconstructed
using onlay Rib Grafts, where the rib was harvested,
splitted and applied to the defect.
In all cases all the prolapsed orbital contents
(preorbital fat, inferior rectus muscle and inferior
oblique muscle) were freed from the maxillary
sinus and free eye movement was ensured. After
grafting, closure was done according to planes of
access to the orbit with careful closure of periosteum
to avoid extrusion of the applied graft.
Postoperative patient care was done including
medical treatment in the form of intravenous fluids,
analgesics, antibiotics and postoperative followup
CT. Moreover, ophthalmology examination was
a routine. Examination to our patients was done
at our outpatient clinic at 1, 3 and 6 months postoperatively.
Digital photos were taken at the time
of injury, pre-and post-operative and with followup
visits. Complications if any were noted for
further assessment and management.
RESULTS
The most common preoperative complaints
were diplopia in 18 patients (60%) and parathesia
of the ipsilateral infraorbital nerve in 12 patients
(40%). Concerning the etiology of fractures were
recorded MCA was the causative factor in 18 cases
(60%), fights and direct trauma in 12 cases (40%).
Four cases had temporarily scleral show postoperatively
(2 cases in Group 1 and 2 cases in
Group 2) and were managed conservatively. Seven
cases had diplopia (two in Group 1 and five in
Group 2), which improved completely within 6
months postoperatively. By palpation the onlay
Rib Graft was felt (Group 2) in three patients at
the edge of the infraorbital rim. No complications
to the donor site were observed. Commonly occurring
complications such as hemorrhage, infection
and wound disruption were not present in the
outcome of this study. All patients were satisfied
with their postoperative outcome with significant
Egypt, J. Plast. Reconstr. Surg., July 2018 275
improvement in esthetic appearance, and return to
normal life activities within three weeks. Symmetry
was restored among the injured and uninjured
sides.
All results were statistically analyzed using
IBM SPSS22 program (2-paired t-test) where all
collected data showed no statistical significance
concerning age, sex, mode of trauma and the size
of the defect relative to the method of reconstruction.
Whereas concerning complications, there was
a higher statistical significance for reconstruction
by conchal cartilage graft compared to reconstruction
by split rib graft.
Table (1) shows that there is no statistical
significant difference as regards age, sex, mode of
trauma and size of the defect. Whereas there is a
highly significant relation between the rate of
complications and the technique of reconstruction,
the p-value of the conchal cartilage graft “group
1”(p=0.00) is of higher significance than the pvalue
(p=0.02) of the onlay split rib graft “group
2”.
Table (1): Comparing the two methods of Orbital floor reconstruction by conchal cartilage
graft and onlay split rib graft.
Sig.
p-value
0.1
0.1
0.2
0.1
0.00
Mean
(cm)
38.60
0.33
0.53
0.67
3.46
Std.
Deviation
6.30
±0.48
±0.64
±0.22
±1.41
Age
Sex
Mode of trauma
Size of Defect
Complications
35.13
0.37
0.46
0.17
2.06
Mean
(cm)
Std.
Deviation
±5.68
±0.45
±0.74
±0.27
±1.53
Sig.
p-value
0.12
0.2
0.3
0.3
0.02
Group (1) Conchal
CartilageGraft
Group (2)
Onlay Rib Graft
Fig. (1A): The defect after transconjunctival incision. Fig. (1B): Harvesting Conchal Cartilage Graft.
Fig. (1C): Conchal Cartilage Graft. Fig. (1D): Conchal Cartilage Graft application.
DISCUSSION
Treatment of the orbital floor fractures is a
controversial issue concerning the reconstructive
material. Different materials are used either autologous
or alloplastic materials. In our study, the
choice of autologous materials was motivated by
the low cost, low morbidity and their biocompatibility.
In this study, we compared the results of
reconstruction of posttraumatic orbital floor defects
by autologous cartilage grafts and onlay rib grafts.
Due to the easy access for harvest and the
possibility to shape, cartilage has the ability to
support the surrounding tissues without resorption
[4]. There are many sources for autogenous cartilage,
one of which is the auricular concha. It is
readily available for repair of orbital floor defects
[16]. Constaintian in 1982 used conchal cartilage
for repair of orbital defects <2cm2 and vouched
for graft tailoring with ease due to the natural curve
that nicely fits the orbital floor [17].
According to Bayat et al., being an abundant
and accessible autogenous source that can easily
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support the orbital floor with minimal morbidity
renders cartilage perfect as a grafting material. All
this and more makes it questionable to why it is
not regularly utilized as a reconstruction material
[18].
Also Talesh et al., [19] and Ozyazgan et al., [7]
in their studies recommended the use of cartilage
grafts for reconstruction of orbital floor defects,
due to its ideal flexibility, satisfactory resistance
supporting the orbital contents.
In our study, Group 1 had comparable results
to other studies with statistical significance concerning
the rateof complications (p=0.00) Compared
to the other group in our study. Moreover
low morbidity of donor site and no aesthetic deformity
postoperatively matches well with the
results of other studies [10,19].
Onlay Rib Graft, being an autologous bone, it
is characterized by its strength and vascularization
potential. Being an autologous source of living
tissue, common side effects such as foreign body
reactions including infection, formation of capsule,
Fig. (2A): Onlay Rib Graft. Fig. (2B): Using Onlay Rib Graft in the reconstruction of
orbital floor defect.
Fig. (3A): Preoperative (A) of Coronal CT defect of left orbital
floor fracture.
Fig. (3B): Postoperative (B) of Coronal CT defect of left
orbital floor fracture reconstructed by cartilage
graft.
Egypt, J. Plast. Reconstr. Surg., July 2018 277
extrusion and ocular tethering are reduced [9].
Despite all the strengths of using the autologous
bone graft, some unfavorable aspects need to be
taken into consideration.
Mintz et al., in their study stated that bone is
not that easy to yield into the needed shape and if
done without care, it could easily break [20]. Lin
et al., in his study showed that bone graft resorption
could not be predicted or anticipated [12,21,22], the
degree of which could not be priory identified.
In cases of using an autologous bone graft from
a remote donor site, increase in time under general
anesthesia and operating time could occur, in
addition to risks related to the donor site [9]. In
our study, group 2 showed comparable results with
other studies using split rib grafts concerning the
rate of complications and aesthetic outcome.
In this study, the results were assessed statistically
to reach the conclusion that both are good
reconstructive materials; but the conchal cartilage
grafts has less drawbacks regarding donor site
morbidity, moreover the usage of bilateral sutured
conchal cartilages helped in some cases to overcome
the problem of defect size reaching 2Cm2.
Conclusion:
Conchal cartilage graft is one of the most suitable
autogenous graft sources for repair of defective
small orbital floor fractures up to 2cm2. It has the
advantages of readily obtainable, could be adapted
to the orbital floor with minimal morbidity to the
donor site and adequate for reconstruction with
good aesthetic outcome.