Unilateral Zygomaticomaxillary Complex Fractures Research Articles

Proactive Surgical Management and Outcomes of Unilateral Zygomaticomaxillary Complex Fractures in Major Trauma Patients: A National Level I Center Experience.

Managing facial trauma in patients with severe polytrauma presents significant challenges due to competing priorities, poor systemic conditions, and delayed surgical timing. At a national level I trauma center, the authors evaluated the feasibility and outcomes of proactive surgical intervention for unilateral zygomaticomaxillary complex (ZMC) fractures in severe trauma patients. This retrospective study included 81 patients with unilateral ZMC fractures treated at a regional level I trauma center between October 2019 and August 2021. Patients were categorized into high and low trauma severity groups based on the injury severity score (ISS). Three-dimensional (3D) computed tomography analyses were performed to evaluate surgical outcomes, including dimensional distances (Dx, Dy, and Dz) and the Asymmetry Index. Of the 81 patients, 52 underwent surgical intervention. No significant differences were observed in 3D distances (Dx, Dy, and Dz) between the high and low ISS groups, both preoperatively and postoperatively. However, postoperative symmetry was superior in the high ISS group (P < 0.010). The average delay from injury to surgery was slightly longer in the high ISS group (8.69 versus 7.35 d, P = 0.248). Complications such as diplopia and paresthesia were more common in the high ISS group, but no significant differences in overall complication rates were observed between the groups. Proactive surgical management of unilateral ZMC fractures in major trauma patients is effective. Despite the systemic challenges in this population, timely intervention resulted in superior postoperative symmetry in the high ISS group and comparable 3D outcomes across trauma severities.

Does More Invasive Surgery Result in Higher Patient Satisfaction? A Long-Term Follow-Up of 136 Zygomaticomaxillary Complex Fractures.

Retrospective with follow-up. To evaluate the long-term satisfaction of surgically treated patients with zygomaticomaxillary complex (ZMC) fractures in relation to the use of internal fixation, number of fixation points, and orbital floor (OF) reconstruction. Secondary objectives were to describe the use of antibiotics and post-operative infections. Patients with unilateral ZMC fractures between 2007-2018 and treatment with either open reduction and internal fixation (ORIF) or closed reduction (CR) were identified from medical records and invited to follow-ups between 2018-2020. Patients were examined, photographed, and completed a questionnaire. A review panel of 3 experienced surgeons evaluated photographs and computed tomography (CT) scans pre- and post-surgery. The study sample consisted of 136 patients (108 ORIF, 28 CR) with a median follow-up time of 76 months. Patient satisfaction of surgical outcome was high (97.8%), with no significant differences in relation to the use of internal fixation, number of fixation points, or OF reconstruction. Dissatisfaction was primarily related to hypoesthesia. On post-operative CT scans, malar asymmetry was more often predicted in patients with 1-point fixations. On questionnaires and photographs, malar asymmetry was more common in patients with 3-point fixations. Prophylactic antibiotics had no effect on the rate of post-operative infections. Patient satisfaction was not influenced by internal fixation, number of fixation points, or OF reconstruction. Selected ZMC fractures can be treated with less invasive approaches. Caution should be observed when predicting long-term malar asymmetry on post-operative CT scans. The findings of this study highlight the importance of a rational and ethical use of surgery.

Modified patient-specific surgical-guide-assisted precise treatment of unilateral comminuted zygomaticomaxillary complex fractures: A 5-year retrospective study

Our study aimed to evaluate modified patient-specific surgical-guide-assisted precise treatment of unilateral comminuted zygomaticomaxillary complex (ZMC) fractures.The retrospective non-randomized study was conducted in a single hospital in China. All patients diagnosed with unilateral comminuted ZMC fractures between January 1, 2018 and December 31, 2022 were retrospectively reviewed. All patients underwent preoperative spiral computed tomography (CT). CT data were processed using software to DICOM format and transferred to Proplan CMF3.0 for preoperative virtual surgical planning and postoperative evaluation. All data were extracted from standardized electronic medical records. All statistical analyses were performed using SPSS version 20.0. The chi-square test and t-test were used for statistical analyses.The 54 included patients were divided into two comparable, equal cohorts of 27 patients, and followed up for at least 6 months. Fracture reduction was assisted using the modified patient-specific surgical guides in the guide group (23 males, four females; mean age 37.74 ± 12.07 years) and without the modified patient-specific surgical guides in the control group (20 males, seven females; mean age 37.44 ± 13.58 years).In the guide group, the mean eminence deviation between the affected and unaffected sides was 1.01 ± 0.92 mm, and the mean width deviation between the affected and unaffected sides was 1.29 ± 1.32 mm. In the control group, the mean eminence deviation between the affected and unaffected sides was 1.99 ± 1.69 mm, and the mean width deviation between the affected and unaffected sides was 2.68 ± 2.01 mm. The differences in facial protrusion (p = 0.001) and width (p = 0.003) symmetry between the affected and healthy sides of the two groups were statistically significant (p < 0.05).In conclusion, applying the modified patient-specific surgical guides to unilateral comminuted zygomaticomaxillary complex fracture reduction has the advantages of greater predictability and effectiveness, and improved bilateral ZMC symmetry. It should be noted that this approach would be especially beneficial for less-experienced surgeons.

Differences Between Patient and Surgeon Perspectives: A Long-Term Follow-Up of 180 Patients With Zygomaticomaxillary Complex Fractures Following Either Conservative or Surgical Treatment.

Retrospective with follow-up. This study described the long-term outcomes of patients who received either conservative or surgical treatment for zygomaticomaxillary complex (ZMC) fractures. It accounted for the perspectives of both patients and surgeons, and explored factors associated with patient satisfaction. Patients with unilateral ZMC fractures 2007-2018 were invited to follow-up clinical examinations and photographic documentation. Patient experiences were recorded using a questionnaire. A review panel assessed computed tomography (CT) scans and photographs. Patient and surgeon perspectives of detecting functional sequelae were assessed, and a correlation matrix was used to evaluate different perspectives of perceiving malar asymmetry. The study sample consisted of 180 patients, of which conservative treatment was given to 43 patients and surgical treatment to 137 patients. Median follow-up time was 72.5months after trauma. Overall satisfaction was 92.8%, with no significant difference between treatment groups. Patients and surgeons showed marked differences in detecting functional sequelae. Predicted malar asymmetry on CT scans did not correlate to findings on photographs or reports by patients. A predicted sunken cheek on CT imaging does not necessarily lead to long-term visible asymmetry of the malar region. Surgeons should acknowledge different perspectives when predicting and assessing long-term sequelae of ZMC fractures, and seek consensus on when to perform surgical reconstructions.

Maxillary sinus volume and facial asymmetry after unilateral zygomaticomaxillary complex fracture reduction with 2, 3, and 4 fixation points: CBCT-based investigation

PurposeThis study aimed to assess the maxillary sinus volume (MSV), Chronic Sinusitis incidence, and asymmetry of the zygomaticomaxillary complex (ZMC) following ZMC fracture surgery with various numbers of fixation points. Materials and methodsIn a prospective non-randomized cohort, 50 adults with unilateral ZMC fractures who treated by open reduction and internal fixation (ORIF) between November 2019 and October 2021 were assigned to accomplish this study. They distributed into three groups as per fixation points (2, 3, or 4 Points). Preoperative (T1), Immediate postoperative (T2), and follow-up (T3) cone beam computed topography were analyzed using the Mimics software. The main measures were MSV and asymmetry indexes (ASI) of six paired bilateral anatomical landmarks (Orbital, Suprajugal, Jugale, Zygon, Maxillozygion 1, and Maxillozygion 2). ResultsMSV decreased significantly on the affected sides postoperatively in 2P and 3P groups, both in T2 and T3. Further, the T2-T3 comparisons showed a significant MSV change (p = 0.001). ASI reduced considerably to clinically tolerated levels (<3 mm) on landmarks near the fixation sites postoperatively. The ASI on the Zygon and Maxillozygion 1 landmarks showed significant changes among the three groups in both T2 and T3. Interestingly, only five cases had reported postoperative sinusitis symptoms. ConclusionsAlthough the MSV was changed among the different fixation point groups, the incidence of chronic sinusitis was uncommon. Bilateral asymmetry affected by number and position of the fixation points, fixation with 4 points provide more symmetry.

Evaluation of Infraorbital Nerve Recovery and its Effect on Quality of Life following Open Reduction and Internal Fixation of Zygomaticomaxillary Complex Fractures - An Evaluative Study.

The zygomaticomaxillary complex (ZMC) fractures are the second most common fractures affecting the midfacial skeleton. Neurosensory disturbances of the infraorbital nerve are one of the most common signs of ZMC fractures. The aim of the study was to evaluate the neurosensory recovery of the infraorbital nerve and its effect on the quality of life (QoL) following open reduction and internal fixation of ZMC fractures. Thirteen patients clinically and radiologically diagnosed with unilateral ZMC fractures with neurosensory deficits of the infraorbital nerve were enrolled for this study. All patients were assessed presurgically for neurosensory deficits of the infraorbital nerve using the various neurosensory tests, followed by open reduction with two-point fixation under general anaesthesia. The patients were followed up at one, three and six months postoperatively to evaluate the recovery of neurosensory deficits. Recovery of tactile and pain sensation was relatively complete in 84.62% and 76.92% of patients respectively by the end of six months postoperatively. The spatial mechanoreception of the affected side improved significantly. 61.54% of patients led an excellent QoL six months postoperatively. The majority of the patients with ZMC fractures and neurosensory deficits of the infraorbital nerve, when treated with open reduction and internal fixation, have complete recovery of the neurosensory deficits by the end of six months postoperatively. However, some patients may continue to experience some long-term residual deficits, which can affect the patient's QoL.

Automated 3D Analysis of Zygomaticomaxillary Fracture Rotation and Displacement.

Background:The zygomaticomaxillary complex (ZMC) can experience a multitude of deforming forces. There is limited understanding on which deformities alter patient outcomes. This study utilized an automated, three-dimensional analysis to elucidate which fracture patterns and rotational deformities are most prevalent and associated with postoperative complications.Methods:This study was a 7-year retrospective review of patients with unilateral ZMC fractures who underwent surgical intervention. Patient demographics, injury mechanisms, presenting symptoms, and postoperative outcomes were collected. Segmentation was completed using Mimics software. The lateral-medial, superior-inferior, and anterior-posterior axes were manually identified on the zygoma and then displacement, rotational direction, and rotational degrees were automatically calculated using Geomagic software. Total displacement score was generated by summation of individual displacement scores at each of the five sutures.Results:Eighty-one patients satisfied inclusion criteria. The most prevalent rotational pattern of the zygoma was medially-superiorly-posteriorly (P < 0.001). When comparing rotation along the three axes, the zygoma had the greatest rotation along the lateral-medial axis compared with the superior-inferior (P = 0.003) and anterior-posterior (P < 0.001) axes. Within each axis, the zygoma was more likely to rotate medially than laterally (P = 0.003) and posteriorly than anteriorly (P = 0.01). Multivariate analysis identified total displacement scores and degrees rotated along the lateral-medial axis as significant predictors of facial complications and reoperation.Conclusions:This study suggests that patients with unilateral ZMC fractures who undergo surgical intervention are at an increased risk for adverse outcomes with greater rotation along the lateral-medial axis and higher total displacement scores. Additionally, the automated analysis method described can provide objective data to better characterize ZMC fractures.

Incidence, Aetiology, and Associated Fracture Patterns of Infraorbital Nerve Injuries Following Zygomaticomaxillary Complex Fractures: A Retrospective Analysis of 272 Patients.

Retrospective study. Zygomaticomaxillary complex (ZMC) fractures are common facial injuries with heterogeneity regarding aetiologies, fracture types, infraorbital nerve (ION) involvement, and treatment methods. The aim of this study was to identify associations between aetiologies, fracture types, and neurological complications. Additionally, treatment methods and recovery time were investigated. Medical files of 272 patients with unilateral and bilateral ZMC fractures were reviewed, whose cases were managed from January 2014 to January 2019 at the Department of Oral and Maxillofacial Surgery, University hospitals Leuven, Belgium. History of ION sensory dysfunction and facial nerve motoric dysfunction were noted during follow-up. ION hypoaesthesia incidence was 37.3%, with the main causes being fall accidents, road traffic accidents, and interpersonal violence. Significant predictors of ION hypoaesthesia were Zingg type B fractures (P = 0.003), fracture line course through the infraorbital canal (P < .001), orbital floor fracture (P < 0.001), and ZMC dislocation or mobility (P = 0.001). Of all ZMC fractures, 37.3% exhibited ION hypoaesthesia. Only ZMC Zingg type B fractures (74.0%) were significantly more associated with ION hypoaesthesia. ION hypoesthesia was more likely (OR = 2.707) when the fracture line course ran through the infraorbital canal, and was less dependent on the degree of displacement. Neuropathic pain symptoms developed after ZMC fractures in 2.2% patients, posing a treatment challenge. Neuropathic pain symptoms were slightly more common among women, and were associated only with type B or C fractures. No other parameters were found to predict the outcome of this post-traumatic neuropathic pain condition.

Clinical Criteria for Selective Exploration of Orbital Floor in Zygomaticomaxillary Complex Fractures.

Exposing the orbital floor requires a surgical procedure that has its own challenges. Despite the meticulous clinical examination followed by sophisticated imaging modalities, orbital floor defects associated with zygomaticomaxillary complex (ZMC) fractures may evade diagnosis and appropriate management. If surgeons can decide about the need for orbital floor exploration in patients with ZMC fracture, the chance of a postoperative eyelid deformity can be prevented. The aim of this article is to assess whether an association exists between the pattern of fracture line and the need for exploration of the orbital floor in ZMC fracture. A retrospective study of 94 patients with isolated, unilateral ZMC fractures who were treated at our unit by open reduction of the ZMC complex with internal orbital exploration from January 2016 to January 2018. The records of all patients were reviewed and specific data related to fracture pattern and orbital floor defect were registered and assessed. Of the 94 cases with isolated, unilateral ZMC fractures, in 80 cases the fracture line propagated to the orbital floor, which required exploration but did not required any reconstruction and only the infraorbital rim was addressed; 14 of them required orbital floor reconstruction. Among the cases which required orbital floor reconstruction, the majority of the cases where those with fracture involving medial side of infraorbital foramen (n = 10) followed by lateral side (n = 3) and through the foramen (n = 0) and lastly bilateral side of the foramen (n = 1). The present study highlights the pattern of fracture line at the level of infraorbital rim can predict the need for orbital floor exploration while treating ZMC fractures for purpose of orbital floor reconstruction. Based on the results and a review of the records, authors strongly recommend the need for exploration of orbital floor when the fracture line passes medial to the infraorbital foramen.

Assessment of Infraorbital Nerve Parasthesia after ZMC Fracture and Its Surgical Repair

Background: Infraorbital nerve parasthesia is a very common finding after maxillofacial trauma involving zygomaticomaxillary complex (ZMC) region. The use of computer assisted surgical protocols for managing these fractures could improve the surgical outcome and maximize the functional and esthetic reconstruction of traumatized bones with possible effect on infraorbital nerve recovery. Objective: The aim of the present study was to assess infraorbital nerve parasthesia after ZMC fracture and its surgical repair. Patients and Methods: A total of 10 patients with unilateral ZMC fractures were selected from those having maxillofacial injuries at the Emergency Room of Sayed Galal University Hospital, Al-Azhar University, Cairo. Patients were divided randomly into two groups (five patients each); Group I: patients were treated with mirror imaging technique and fabrication of a steriolithographic (STL) model. Group II: patients were treated through the traditional technique without fabrication of an STL model. Results: Infraorbital nerve affection occurred in 7 patients (70%), 4 in group I and 3 in group II. Recovery of the nerve occurred at 3 months postoperatively except for only one patient from group II. Statistically, no significant difference was found between both groups. Conclusion: Although computer assisted surgery is impressive and has a remarkable role in facilitating the precise contouring and adaptation of the titanium plates / mesh needed for fracture repair, it has no evident advantages over the traditional techniques regarding infraorbital nerve recovery.

Assessment of Infraorbital Nerve Parasthesia after ZMC Fracture and Its Surgical Repair

Background: Infraorbital nerve parasthesia is a very common finding after maxillofacial trauma involving zygomaticomaxillary complex (ZMC) region. The use of computer assisted surgical protocols for managing these fractures could improve the surgical outcome and maximize the functional and esthetic reconstruction of traumatized bones with possible effect on infraorbital nerve recovery. Objective: The aim of the present study was to assess infraorbital nerve parasthesia after ZMC fracture and its surgical repair. Patients and Methods: A total of 10 patients with unilateral ZMC fractures were selected from those having maxillofacial injuries at the Emergency Room of Sayed Galal University Hospital, Al-Azhar University, Cairo. Patients were divided randomly into two groups (five patients each); Group I: patients were treated with mirror imaging technique and fabrication of a steriolithographic (STL) model. Group II: patients were treated through the traditional technique without fabrication of an STL model. Results: Infraorbital nerve affection occurred in 7 patients (70%), 4 in group I and 3 in group II. Recovery of the nerve occurred at 3 months postoperatively except for only one patient from group II. Statistically, no significant difference was found between both groups. Conclusion: Although computer assisted surgery is impressive and has a remarkable role in facilitating the precise contouring and adaptation of the titanium plates / mesh needed for fracture repair, it has no evident advantages over the traditional techniques regarding infraorbital nerve recovery.

Does Zygomatic Complex Symmetry Differ Between Healthy Individuals and Surgically Treated Patients Using Intraoperative 3-Dimensional Cone Beam Computed Tomographic Imaging?

Reconstruction of symmetry after zygomaticomaxillary complex (ZMC) fractures is essential for esthetic appearance as well as function. Therefore, this study aimed to analyze whether bony facial symmetry in patients surgically treated for unilateral ZMC fractures via intraoperative imaging differs from that of healthy individuals. Retrospective and cross-sectional radiographic measurements of patients treated for unilateral ZMC fractures via intraoperative cone beam computed tomography (CBCT) were performed to evaluate the postoperative ZMC symmetry. The same number of healthy individuals without any history of midfacial trauma matched for age and gender served as the control group. Asymmetry of the ZMC was determined by measuring bilateral differences in the malar eminence position on CBCT. In addition, demographic statistics, etiology, and fracture type were analyzed. Analysis of 57 surgically treated patients and 57 healthy individuals with a mean age of 29years was performed. No significant difference in the symmetry of the malar eminence position was observed between healthy individuals and patients treated for a unilateral ZMC fracture (P=.890). In one third of patients, corrections were needed after intraoperative CBCT control. The results of this study indicate that, on average, a ZMC asymmetry of 1.6mm is observed in healthy individuals. Furthermore, the use of intraoperative CBCT for the treatment of dislocated ZMC fractures helps to achieve precise anatomic, symmetrical repositioning and is suggested to improve the quality of care.

A Consistent, Reliable Landmark to Assist in Placement of Orbital Floor Reconstruction Plates After Blowout Fractures.

To define a reliable and consistent landmark, the superior posterior wall of the maxillary sinus, and to describe how this landmark can be used when repairing orbital floor fractures. Retrospective chart review. Patients >18 years old diagnosed with unilateral orbital floor and/or zygomaticomaxillary complex fractures. The distance from the inferior orbital rim to the superior posterior wall of the maxillary sinus (landmark distance), and the distance from the landmark to the entrance of the optic canal were reported. Eighty patients were included in the study. Each had unilateral isolated orbital floor fractures (n = 46) or unilateral zygomaticomaxillary complex fractures with an orbital floor component (n = 34). The contralateral eye in all patients was uninjured, and was used as an internal control. In orbital floor fractures, the mean landmark distance was 38.8 ± 1.4 mm, with a mean distance on the normal side of 38.8 ± 1.6 mm (P = 0.49). Distance to the optic canal on the injured side in isolated orbital floor fracture patients was 9.0 ± 0.8 mm with the same measurement on the normal side being 8.8 ± 0.7 (P = 0.21). In the setting of zygomaticomaxillary complex fracture, the orbital floor length was 38.2 ± 1.3 mm with a mean normal floor length of 37.8 ± 1.1 mm (P = 0.18). The mean distance from the superior posterior wall to optic canal in zygomaticomaxillary complex fractured orbits was 9.2 ± 1.1 mm with a normal side mean length of 9.5 ± 1.0 mm (P = 0.23). No significant difference was found between the measured distances in the fractured orbit and its normal counterpart for both fracture groups. The superior posterior wall of the maxillary sinus is a reliable landmark that can be used to assist in placement of an orbital floor reconstructive plate. The landmark is unchanged despite the presence of an orbital floor or zygomaticomaxillary sinus fracture.

Enophthalmos and Orbital Volume Changes in Zygomaticomaxillary Complex Fractures: Is There a Correlation Between Them?

The orbital cavity can be affected in zygomaticomaxillary complex (ZMC) fractures. The aim of this study was to assess the relation between orbital volume changes and enophthalmos in patients with ZMC fractures. A descriptive study of consecutive adult patients with recent isolated unilateral ZMC fractures who were otherwise healthy was performed from 2016 through 2017. Multislice computed tomographic (CT) scans were taken of all patients and enophthalmos was measured clinically using a Hertel exophthalmometer. In the axial plane, enophthalmos was measured on CT scan using Mimics software. Three-dimensional reconstruction and volume measurement of the orbital cavity also were performed using Mimics software. The correlation between clinical and radiographic amounts of enophthalmos was measured by Pearson correlation coefficient analysis. The association among radiographic enophthalmos, clinical enophthalmos, and volume changes of the orbital cavity was assessed by linear regression. The P value was set at .01. Ninety-six patients (77 men, 19 women; mean age, 28.48±8.29yr) were assessed. Mean volumes of control and fractured bony orbits measured on CT scan were 29.02±1.71 and 32.05±2.22cm3, respectively (P<.001). There was a strong positive correlation between clinically and radiographically measured amounts of enophthalmos (correlation coefficient=0.97; P<.001). Based on the linear regression model, for each 1-cm3 orbital volume change, clinical and radiographic enophthalmos amounts changed by 0.68 and 0.71mm, respectively (P<.0001). ZMC fractures commonly increase orbital volume and the degree of change is strongly correlated with enophthalmos.

The clinical course of diplopia associated with zygomaticomaxillary complex fractures before and after surgery

ObjectiveDiplopia is a common complaint following zygomaticomaxillary complex (ZMC) fractures. The present study was conducted to evaluate the prevalence of post-traumatic as well as port-operative diplopia, and the improvement of diplopia over time before and after surgery. MethodsA retrospective case series of diplopia associated with ZMC fractures was conducted to address the research purpose. Only subjects with isolated unilateral ZMC fractures were included. Demographic variables included age and gender of the patients. The primary outcome variable of this study was the presence of diplopia during different periods before and after surgery. Descriptive statistics were conducted for all variables studied. Analytical statistics were performed to measure the significance of change in the outcome variable during different stages of treatment. ResultsIn total, 231 patients were included, with a mean age of 23.78 (±5.11) years. Post-traumatic diplopia was diagnosed in 59% of patients. Only 13% of cases had pre-operative diplopia. Post-surgical diplopia was reported in 37% of cases. Post-operative follow-up diplopia showed a significant improvement over time with only 1 patient having residual diplopia 6 months after surgery. ConclusionsTraumatic diplopia in unilateral ZMC fractures is common. However, a significant resolution of diplopia over time should be expected. Residual diplopia is an unlikely outcome.

Single incision technique for two-point fixation of zygomaticomaxillary complex fractures

ObjectiveThe aim of this study is to discuss the Y modification of transconjunctival approach in the management of zygomaticomaxillary complex (ZMC) fractures. Study design10 patients with unilateral ZMC fractures were included in this study. All patients were treated by two-point fixation through single incision by the Y modification of transconjunctival approach. The average follow up period was 6 months. The adequacy of exposure, cosmetic outcomes, intraoperative, and postoperative complications were evaluated. ResultsThe exposure was excellent in all patients with good cosmetic outcomes. None of the patient had any intraoperative complications; postoperatively, one patient had mild displacement of lateral canthus and other had mild hyperpigmentation of scar. ConclusionThe transconjunctival Y modification is a relatively new technique and provides excellent exposure and good esthetics. Yet, studies on large cohort needed to use this approach in the routine management of ZMC fractures.

Functional Evaluation of the Behavior of Masticatory Muscles in Zygomaticomaxillary Complex Fracture: A Prospective Study.

The purpose of this study is to functionally evaluate the behavior of the masticatory muscles (masseter and temporalis) following zygomaticomaxillary complex (ZMC) fractures by assessing bite force, electromyography (EMG), and mandibular movements. Group I consisted of 20 patients with unilateral ZMC fractures who were treated surgically with one-, two-, or three-point fixations at the frontozygomatic, infraorbital, or zygomaticomaxillary buttress region as per clinical and radiological assessments. Group II control group included 20 normal patients. The muscle activity was functionally evaluated before and after the surgery for a period of 6 months. The evaluation consisted of bite force measurement, EMG analysis of masseter and temporalis muscles, and measurements of mandibular movements. There was an increase in bite force and EMG activity throughout the evaluated postoperative period, but at the end of 6 months, the values were still below the control levels for majority of the patients. Maximum mouth opening increased considerably after the surgery. According to bite force and EMG, the masticatory musculature returned to near normal levels by the 3rd month after the surgery. Management of fractures of the zygoma by open reduction and fixation raises the question of the location of fixation points owing to the action of masseter and temporalis on the ZMC. This study supports the current clinical concept of minimized fixation in treating ZMC fractures.

Investigation of infraorbital nerve injury following zygomaticomaxillary complex fractures

The aim of this study was to investigate the severity of infraorbital nerve injury following zygomaticomaxillary complex fractures and to estimate the treatment methods facilitating its functional recovery. A total of 478 patients with unilateral zygomaticomaxillary complex fractures were treated. Infraorbital nerve sensory disturbances were diagnosed in 64.4% of the patients. Injury of the infraorbital nerve was expressed as asymmetry index, which was calculated as a ratio between the affected side and the intact side electric pain detection thresholds at the innervation zone skin before treatment and 14 days, 1, 3, 6 and 12 months postoperatively. A mean asymmetry index of 0.6 +/- 0.03 and 1.9 +/- 0.5 was registered for 57 (11.9%) patients with hyperalgesia and for 251 (52.5%) patients with hypoalgesia, respectively. As a result of retrospective analysis of infraorbital nerve sensory disturbances and its functional recovery, infraorbital nerve injury severity was classified as mild, moderate and severe. It was found that the dynamics and outcome of the functional infraorbital nerve recovery depend on the severity of the injury and the presence of infraorbital canal damage. Function was completely recovered within 3 months after treatment in cases with mild nerve injury. In moderate cases, complete recovery was seen within 6 months and in 34.6% of the severe cases, within a 12-month period after treatment when infraorbital nerve decompression was performed according to the stated indication. Treatment based on infraorbital nerve injury classification offers a better prognosis for complete recovery of the infraorbital nerve function.

Status of the internal orbit after reduction of zygomaticomaxillary complex fractures

Purpose We sought to determine the status of the internal orbit before and after reduction of zygomaticomaxillary complex (ZMC) fractures when treated without internal orbital reconstruction. Patients and methods We conducted a retrospective study of preoperative and postoperative computed tomography (CT) scans in 65 patients with unilateral ZMC fractures who were treated by reduction of the ZMC complex without internal orbital reconstruction. The size and location of the internal orbital defects, orbital soft tissue displacement, and orbital volume were assessed in the preoperative and postoperative CT scans. Results Reduction in the ZMC fractures was considered ideal in 58 of the 65 patients. Only minor malpositions occurred in the remaining 7 patients. The size of the internal orbital defects increased slightly with ZMC reduction but the internal orbital fractures were realigned, and few had increases in orbital volume or soft tissue sagging into the sinuses. Examination of follow-up CT scans in several patients taken weeks to months later showed that the residual defects became smaller and that none of these patients had an increase in orbital volume or soft tissue sagging. Conclusion The preoperative CT scan can be used to assess the amount of internal orbital disruption for purposes of developing a treatment plan in patients with ZMC fractures. When there is minimal or no soft tissue herniation and minimal disruption of the internal orbit, ZMC reduction is adequate treatment.

Analysis of treatment for isolated zygomaticomaxillary complex fractures

aPurpose The purpose of this study was to evaluate the adequacy of reduction and stability of fixation of isolated zygomaticomaxillary complex (ZMC) fractures treated by various methods over a 5-year period.Patients and Methods Forty-eight patients with isolated, unilateral ZMC fractures that had at least 6 weeks' clinical follow-up were studied. Demographic information and methods of treatment were obtained from the medical records. Quality of reduction was assessed by examination of postoperative images. Stability of the repositioned ZMC was assessed by comparing immediate postoperative images with those obtained at least 5 weeks later. Cosmetic outcomes were assessed by clinical assessment and examination of photographs.Results A variety of surgical approaches and fixation sites were used in the sample. All patients but five had satisfactory reductions performed during surgery. In two of the latter, no noticeable facial deformity was apparent. No patient showed postsurgical change in position of the reduced ZMC. Three patients showed postsurgical enophthalmos at longest follow-up. Approximately 20% of those having lower eyelid incisions had some amount of scleral show at longest follow-up.Conclusions A variety of techniques can be used to produce a satisfactory outcome. Based on the results and a review of the literature, recommendations for treatment are proposed.