Clinical Evaluation of Neurosensory Changes in the Infraorbital Nerve Following Surgical Management of Zygomatico-Maxillary Complex Fractures

Abstract

Introduction: Zygomatico-orbital fractures are the second most common facial injuries. Trauma to mid-facial region can lead to an alteration or loss of sensation in the facial region which sometimes requires early surgical intervention to aid in an early recovery.

Aim: To evaluate the different neurosensory changes in the infraorbital nerve function following common treatment modalities used in the management of zygomatico-maxillary complex fractures.

Materials and methods: Thirteen patients selected for the study had unilateral zygomatic complex fracture with altered sensation in the region of distribution of the infraorbital nerve. The fractures were managed either by reduction followed by internal fixation with mini-plates (Group A), reduction alone (Group B) or conservatively (Group C). Infraorbital nerve function tests were done by mechanical, heat and pain threshold detection. Evaluation was done on 1(st), 3(rd), 7(th) day, one month, three months and six months interval in a manner similar to that done at the beginning of the study (Day0).

Results: A male predominance with male:female ratio of 5.5:1 and an age range of 21 to 50 years was found with the right side mostly affected. Road traffic accident was the most common aetiology. Most common clinical presentations were sub-conjunctival haemorrhage (84.61%), flattening of the malar prominence (69.23%) with deficit in neurosensory function of infra orbital nerve. Recovery in the infraorbital nerve function was relatively complete in 76.92% cases with partial recovery in 23.07% of the patients.

Conclusion: Marked improvement in the neurosensory function of the infraorbital nerve was found when some form of treatment either in the form of Open Reduction and Internal Fixation (ORIF) or approach through Gillie's temporal or Keen's intraoral approach were applied as compared to when conservative treatment was provided. In zygomatic complex fractures, any form of treatment employed brought about decompression of the infraorbital nerve which aided in the recovery of the nerve within a span of 1-6 months, except when no treatment was applied.

Keywords: Gillie’s approach; Henderson’s classification; Hypoesthesia; Infra-orbital nerve; Paresthesia.

[Table/Fig-1]:

Sub-conjunctival haemorrhage

[Table/Fig-2]:

Depressed malar arch

[Table/Fig-3]:

Step at the fronto-zygomatic suture

[Table/Fig-4]:

Surgical exposure of the zygomatic buttress

[Table/Fig-5]:

Surgical exposure of the infraorbital rim

[Table/Fig-6]:

Open reduction with internal fixation

[Table/Fig-7]:

Mechanical threshold detection by 7-0 nylon monofilament

[Table/Fig-8]:

Thermal threshold detection

[Table/Fig-9]:

Pain threshold detection by acupuncture needle

[Table/Fig-10]:

Exploring the infra-orbital nerve

[Table/Fig-11]:

Incision with exposure of temporo-parietal fascia

[Table/Fig-12]:

Zygoma elevation

[Table/Fig-13]:

1 month post-operative view

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3 months post-operative view

[Table/Fig-15]:

6 months post-operative view