Retrospective Study over 15-years Period on Zygomathic arch Fractures: A Single Center Experience

Abstract

The purpose of this study was to do a retrospective analysis about patients with zygomatic arch who were treated at the department of Maxillofacial Surgery, Regional University Hospital of Ancona, Italy, between 2007 and 2021. Patients were evaluated based on various parameters including age, sex, aetiology, symptoms, comorbidity, clinical findings, zygomatic arch fracture type, other facial fractures, treatment, waiting time before the operation, complications and sequelae. In the period described we recorded 103 zygomatic arch fractures. Of the patients, 64 were male (65,92%) and 39 were female (34,08%). The average age of the patients was 47,02 years (ranging from 8 to 93 years). The leading cause of these fractures was sports-related injury (n = 24; 23,30%), and isolated zygomatic arch fractures were the most frequent (63,1%). The most common clinical signs and symptoms were, pain, depression of the facial profile, difficulty in chewing, limitation of the buccal opening, difficulty in protrusion movements and mandibular lateralization. 93% of patients underwent surgery under local anesthesia, almost exclusively patients undergoing an open approach to internal fixation. The successful and effective management of zygomatic arch fractures requires a solid understanding of its anatomy, pathophysiology and related biomechanical structures and forces. The continuous research in epidemiology, aetiology, materials and techniques will further refine our treatments which are nowadays more and more customized according to the type of trauma.

Introduction

One of the most common facial skeleton fractures is the zygomatic arch fracture. They can occur in single or multiple portions of the zygomatic arch. Furthermore, they can occur alone or in association with other fractures of the face. The zygoma and in particular the arch represent a bone structure particularly exposed to trauma, especially in falls, since it has a remarkable lateral projection.

The frequency of this type of fracture is slowly increasing due to the increasing number of traffic accidents, work accidents, sport-related injuries, physical assaults and accidental falls. These types of fractures can cause significant functional and cosmetic consequences such as lateral depression of the patient’s face, pain, limitation of the buccal opening, injury to vascular and nervous structures.

Zygomatic arch fractures can be evaluated through various types of classification based on: the site of the fracture, the type of fracture gap, the presence of impediments to the buccal opening [1].

The aim of the present study was to evaluate the clinical and epidemiological results of zygomatic arch fractures treated at our centre, focusing on the association between surgical timing and drawing conclusions on the different types of surgical approaches and the related results at medium and long term.

Materials and Methods

We retrospectively reviewed the clinical history of 103 patients evaluated for zygomatic arch fractures between 2007 and 2021 at the department of Maxillofacial Surgery of the Ospedali Riuniti of Ancona (Italy).

Patients who had previously been treated for such fractures were excluded. Various parameters have been considered: age, sex, etiology, symptoms, comorbidities, clinical findings, zygomatic arch fracture type, other facial fractures, treatment, waiting time before the operation, complications and sequelae.

Computer tomography (CT) was performed before surgery to classify the zygomatic arch fractures and to choose the most suitable method of reduction and stabilization and after surgery to evaluate the results.

Results

Among patients, 64 were male (65,92%) and 39 were female (34,08%). The average age of the patients was 47,02 years (ranging from 8 to 93 years).

Patients were divided into 8 groups according to age (10 years intervals) with a separate group to include pediatric patients (0–14 years): 9 patients (8,73%) were younger than 14 years. 11 patients (10,67%) were between 15 and 24 years of age, 12 (11,65%) between 25 and 34 years, 18 (17,47%) between 35 and 44 years, 17 (16,50%) between 45 and 54 years, 13 (12,60%) between 55 and 64 years, 12 (11,65%) between 65 and 74 years, and 11 patients (10,67%) were older than 75 years (Fig. 1).

Fig. 1.

Age distribution of patients

As regards the type of fracture, we mainly witnessed simple, moderately displaced and closed fractures with a total number of 53 cases out of a total of 103. Green stick fractures were mainly found in children (n = 6). However, pluricomminute, complicated, open fractures were less frequent. Multiple fractures at the zygoma level have been reported in 38 cases (36,89%) mainly involving the zygomatic body and ach together.

The principal etiology of zygomatic arch fractures was sports-related injury (n = 24; 23,30%), followed by violent assault (n = 22; 21,35%), falling down (n = 18; 17,47%), domestic accidents (n = 14; 13,59%), traffic accidents (n = 13; 12,62%), and accidents at work (n = 10; 9,70%) (Fig. 2).

Fig. 2.

Percentage of etiology

We reported 2 patients (1,94%) with unknown causes as undeclared or due to errors in medical history.

Violent assault was the leading cause of zygomatic arch fractures among male patients; traffic accidents were most common in female; accidental falling was the most frequent cause in older patients (> 75 years) and sport-related injuries were the most common cause in male patients aged between 0 and 35 years.

Systemic traumatic involvement was reported in 8 patients (7,76%): 2 patients had polytrauma, 5 had cerebral trauma, and 3 had fractures of other skeletal elements.

14 patients presented concomitant facial wounds and 28 patients were affected by other facial fractures (8 lower jaw fractures, 10 nasal bone fractures, 1 frontal sinus fractures and 9 Le Fort type I fractures).

The most frequent clinical signs and symptoms were: lateral depression of the patient’s face, pain, limitation of the buccal opening, injury to vascular and nervous structures.

Post-operative clinical follow-up was performed after 7 days, 3 weeks, 3 months and 6 months post-treatment.

The mean ± standard deviation of time interval between trauma and surgery was 2 ± 3 days. Closed reduction surgery for the zygomatic arch fracture was performed in most cases. In the remaining cases open reduction with internal fixation was performed. The surgical approach was mainly percutaneous with Ginestet hook placed underneath the deepest depression of the fracture of the zygomatic arch. Titanium plates and screws (1.7 system for mid-facial fracture) were mainly used for reduction and internal fixation.

Postoperative complications occurred in 3 patients (2,91%). Immediately after surgery 45 patients had pain in the zygoma area, 7 patients had persistent difficulty opening the mouth, 9 patients had suboptimal healing and 2 patients had persistence of lateral depression of the face. Among 103 patients, only 8 had persistent sequelae after 6 months: 5 with mild depression of the lateral region of the face and 3 patients still report hypoesthesia in the infraorbital region.

93% of patients underwent surgery under local anesthesia, almost exclusively patients undergoing a closed approach without internal fixation. The remaining 7% are patients undergoing surgery under general anesthesia to reduce and stabilize more complex fractures involving not only the zygomatic arch but also, for example, the zygomatic body. Patients undergoing closed reduction of fractures underwent local anesthesia without antibiotic prophylaxis.

In patients undergoing surgery with the open technique, antibiotic prophylaxis was performed as per company protocol (Cefazolin + Metronidazole, modified according to any intolerances and allergies). Reoperation was performed successfully in 3 patients (2,91%) mainly because of residual face depression in the immediate postoperative period, imperfect reduction of the fracture shown by the control CT, infection of the early fixation devices.

In the remaining 100 cases an optimal reduction and stabilization of the fractures of the zygomatic arch was obtained with an adequate lateral projection of the face and above all a good level of satisfaction on the part of the patients.

Discussion

Zygomatic bone fractures are one of the most common facial skeletal injuries in fact is the third most commonly fractured area in the face [2]. In literature, most of zygomatic arch fractures occur in men 30 to 40 years of age, as a result of traffic accidents. However, other studies have reported assault to be the most common mechanism. Isolated zygomatic arch fractures occur in 5% of all patients with facial fractures and in 10% of patients with any zygomatic-maxillary complex fracture.

Zygomatic arch fractures often occur as part of a tripod fracture of the zygoma [3]. This type of fracture may produce a visible depression of the lateral part of the face leading to cosmetic asymmetry and trismus if the arch impinges upon the coronoid process.

If the zygomatic arch fracture is not properly treated, serious functional consequences including impaired mouth opening, temporomandibular joint ankylosis, and rarely facial nerve palsy may occur.

Asymptomatic zygomatic fractures, and fractures with no or minimal displacement, are often treated with observation. However, displaced fractures with functional or cosmetic impairments must undergo surgical treatment.

Several techniques have been described to reduce zygomatic arch fractures; at our centre a percutaneous reduction is performed using a Ginestet hook positioned below the fractured zygomatic arch under local anaesthesia [4].

For the most part, surgical repair results in favourable outcomes. Patient reported functional, aesthetic, and overall satisfaction after zygomatic arch repair.

After reduction of the zygomatic arch, more than 90% of the fractures are stable enough to not require a fixation procedure. This is in part due to the splinting effect provided by the masseter muscle and the temporalis fascia.

In literature there are heterogeneous studies regarding epidemiology, demographic and clinical characteristics of patients, type of surgical approach, materials, and timing to perform surgery.

The purpose of this retrospective study on patients who came to our department for zygomatic arch fracture is to evaluate, over the observed 15-year period, the main causes of trauma, the main fracture patterns of the zygomatic arch and which types of treatment were most applied.

In our department, we reviewed 103 patients with zygomatic arch fractures, excluding patients who had already undergone surgery. The patients in the present study were evaluated by age, sex, aetiology, symptoms, comorbidities, fracture type, treatment, time to surgery after trauma, complications, and sequelae.

It is important to consider that the total population of the Marche region amounts to about 1 million and 400 thousand inhabitants and that our department represents the reference centre for cervical-facial pathology.

In most studies, males are more often affected compared to females; this might be due to greater outdoor participation and higher levels of physical activity in males. Furthermore, males are more likely to be involved in traffic accidents.

In our report, 64 were male (65,92%) and 39 were female (34,08%) and the male/female ratio was about 2:1. The sex ratio observed in other studies was 3:1, 4:1.

In our study the largest number of patients we got was in the 35- to 44-year age group (17,47%) and the 45- to 54-year-old group (16,50%).

There was an average age of 47,02 years among the patients (ranging between 8 and 93 years old).

Fractures of the facial skeleton in children account for only 8,73% of all facial fractures in the population, most frequently between the ages of 5 and 13 years. In children the most common maxillofacial fracture sites are the nose and the dentoalveolar complex, followed by the mandible, orbit, and midface.

There have been several publications on the causes of zygomatic arch fractures including assaults, traffic accidents, work-related injuries, falls, sports injuries, pathological fractures and gunshot injuries.

The most frequent cause of zygomatic arch fracture is represented by sports-related injury and violent assault [5]. Young and male subjects are almost universally victims of facial trauma more frequently than women, and in many countries alcohol is often a significant contributor. Sports injuries are more common in young male adults between the ages of 10 and 30. The main sport identified as a cause of injury was football, followed by basketball and rugby. Accidental falls are more frequent in older patients and especially in the age group over 75 years. A higher incidence of left-sided zygomatic arch fractures was found mainly in those patients who are victims of aggression, due to punches received in the face by mostly right-handed aggressors. We reported that single fractures were found in 74 patients (71,84%) and multiple arch fractures were seen in 29 cases (28,15%).

Systemic traumatic involvement was reported in 8 patients (7,76%): 2 patients had polytrauma, 5 had cerebral trauma, and 3 had fractures of other skeletal elements.

14 patients presented concomitant facial wounds and 28 patients were affected by other facial fractures (8 lower jaw fractures, 10 nasal bone fractures, 1 frontal sinus fractures and 9 Le Fort type I fractures).

The most common clinical signs and symptoms were lateral depression of the patient’s face, pain, limitation of the buccal opening, injury to vascular and nervous structures. Fractures should theoretically be treated as soon as possible but this is not always reliable [6].

For all open fractures (for example fractures associated with a tissue laceration, or involvement of the periodontium), it is possible to say with certainty that the risk of infections is directly proportional to the time that elapses between the trauma and surgery infections.

However, in literature the time frame beyond which the risk of complications or suboptimal surgical results significantly increases is not well understood. We recorded that 89% of patients were treated within 2 days from the traumatic event.

The time between injury and surgery depends on factors such as good clinical condition to tolerate a surgical procedure and the patient’s admission time.

Whatever type of treatment is chosen the main goals to be achieved are: anatomical reduction of the fractures, stability and healing, restoration of correct facial symmetry, restoration of pre-injury mandibular opening where there is impact of the zygomatic arch at the level of the mandibular coronoid avoidance of complications such as infections, malunions or nonunions and nerve injuries. Treatments generally vary according to the fracture type, number and location, surgeon preferences and patient characteristics (age, patient compliance, choice of treatment, etc.) [7].

In case of displaced or multi-comminuted fractures obviously one cannot limit oneself to a surgical treatment of percutaneous reduction of the fracture but a more complex surgical intervention of stabilization of the bone stumps using titanium plates and screws is necessary.

In the present study 96 patients underwent closed reduction without internal fixation. Open approach was followed in 7 patients, including the use of miniplates, monocortical screws or titanium mesh where the orbital walls are involved.

Open reduction was performed only in selected cases, taking into account the patient’s age, the extent of any fracture displacement, the medical conditions and the patient preferences [8]. The mini-invasive surgical solution was the most applied in our department for the management of this type of fracture.

The fundamental treatment method for reduction of multiple and displaced zygomatic arch fractures is the open approach. With bi-coronal incisions, the zygomatic arches are wholly visualized, making accurate reduction possible. Although there are many advantages to the open approach for skeletons, many complications should be considered relating to the soft tissue covering the facial bones. With the coronal approach, soft tissue sequelae such as scalp numbness, alopecia, temporal hollowness, and facial nerve injury must be considered [2]. Therefore this type of approach is limited only to selected clinical cases where closed or minimally invasive surgery does not allow the control of fractures and possible sequelae.

Conclusions

The diagnosis and management of isolated zygomatic arch fractures have been rarely reported in the literature. Effective and successful management of zygomatic arch fractures requires a solid understanding of its anatomy, pathophysiology and the significant aesthetic impact this type of fracture can have especially in the young population. Modern fracture repair is based on techniques of anatomical percutaneous reduction without fixation. However, a positive result requires integrity, some experience and dexterity in perceiving any residual bone discrepancies in the closed reduction. External reduction is a simple technique that, when employed in the appropriate clinical context, provides reestablishment of both form and function with minimal required exposure. Continuous research in epidemiology, aetiology, materials and techniques will further refine the treatments of zygomatic arch fractures.

Authors’ Contributions

All authors contributed equally to the manuscript and read and approved the final version of the manuscript.

Funding

The authors report no involvement in the research by the sponsor that could have influenced the outcome of this work.

Declarations

Conflict of interest

The authors certify that there is no conflict of interest with any financial organization regarding the material discussed in the manuscript.

Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors. The treatment of the presented patient was not in any way influenced due to this article.

Informed consent

The patient provided informed consent.