Two-point versus three-point fixation in the management of zygomaticomaxillary complex fractures: A comparative study

Modeling stability post zygomatic fracture reconstruction

Zygomaticomaxillary complex (ZMC) fracture repair is one of the most common surgical procedures performed in craniomaxillofacial trauma management. Miniplates and screws are used to stabilize the fractured bone using small local incisions, however, these procedures are not infrequently associated with hardware-related post-operative complications. The amount of fixation hardware utilized varies depending on the fracture pattern and surgical judgment, with three-point fixation being the conventionally accepted treatment. However, limited experimental testing and clinical studies have suggested that ZMC stabilization may be achieved with less than three-point fixation. In this study, we utilized a previously developed finite element modeling approach that allows for detailed bone and muscle representation to study the mechanical behavior of the fractured craniomaxillofacial skeleton (CMFS) under one, two, or three-point fixation of the ZMC. Results suggest that using a miniplate along the infraorbital rim in three-point fixation increases the amount of strain and load transfer to this region, rather than offloading the bone. Two-point (zygomaticomaxillary and zygomaticofrontal) fixation yielded strain patterns most similar to the intact CMFS. One-point (zygomaticofrontal) fixation resulted in higher tensile and compressive strains in the zygomaticofrontal region and the zygomatic arch, along with a higher tensile strain on the zygomatic body. These modeling results provide biomechanical evidence for the concept of over-engineering in the stabilization of facial fractures. Furthermore, they support previous suggestions that less than three-point fixation of ZMC fractures may be adequate to achieve uneventful healing.

Direct or Indirect Surgical Approach of Zygomatic Complex Fracture: A Comparative Study

Zygoma is considered the main support of the midface. Zygoma is frequently fractured owing to its prominent site on the face. Treatment of zygomaticomaxillary complex fractures can be performed through either conservative or surgical measures (closed or open reduction). The study was a cross-sectional retrospective observational investigation done at 4 hospitals in Ramadi and Baghdad cities, Iraq. This investigation covered a duration of 6 years (2016-2021). We reviewed the medical records of patients with ZCFs. The participants were divided into 2 groups according to the approach used for their management (direct versus indirect approach). Data regarding the demographic and clinical characteristics were recorded for each subject. Of 265 patients with ZCFs, 209 (78.9%) were males. The highest age group affected was 18 to 40 years (51.7%). The majority of the ZCFs were caused by road traffic accidents (31.7%). Most of the cases belong to single fractures (72.1%). Cheek flattening (73.6%) was the commonest sign of the ZCFs. The majority of the fractures were treated by direct approach, 65.4% of the isolated fractures and 62.2% for multiple fractures. Excellent patient satisfaction was seen in the majority of the cases. There were no statistically significant differences between the 2 approaches regarding the abovementioned variables ( P -value > 0.05). The majority of the cases were with excellent patient satisfaction (n = 149) while only 7 patients with poor satisfaction. The age groups below 18 years and 18 to 40 years were associated with excellent patient satisfaction than good and poor satisfaction. All (n = 7) of the cases with poor satisfaction belong to the age group above 40 years. The majority of male (n = 113) and female (n = 36) patients were with excellent satisfaction, while all patients with poor results were males (n = 7). There were statistically significant differences between the results of the patient satisfaction and age group and complications ( P -value < 0.05). The ophthalmic complications were the most complications seen after ZCF surgical treatment (2.56%). Direct and indirect approaches can be used safely in the treatment of ZCFs owing to excellent patient satisfaction in the majority of the cases and a low complication rate. This study aims to evaluate the demographic and clinical characteristics and to compare different surgical procedures to treat patients with zygomaticomaxillary complex fractures in a country overwhelmed by violence.

Is three-point fixation needed to mechanically stabilize zygomaticomaxillary complex fractures?

Fixation is critical in zygomaticomaxillary complex (ZMC) fractures to avoid malunion; however, controversy exists as to how much hardware is required to achieve adequate stability. Current fixation regimens may not represent the minimum stabilization needed for uneventful healing. Craniomaxillofacial (CMF) computational models have shown limited load transmission through the infraorbital rim (IOR), and a previous experimental study of ZMC fractures has suggested that IOR plating does not alter CMF bone strain patterns. This study aimed to measure the impact of stabilization on fracture site displacement under muscle loading, testing the hypothesis that three-point fixation is not critical for ZMC fracture stability. Four ZMC complex fractures were simulated on two cadaveric samples and stabilized with three-point plating. Displacements simulating mouth openings of 20 mm and 30 mm were applied to the mandible using a custom apparatus. Fracture gap displacement under load was measured at multiple points along each fracture line, and bone strain was captured using a combination of uniaxial and rosette gauges. Data capture was repeated with the IOR plate removed (two-point fixation) and with the zygomaticomaxillary plate removed (one-point fixation). Fracture displacement under muscle loading was consistent, with gaps of less than 1 mm in 95% of cases (range 0.05-1.44 mm), reflecting clinical stability. Large variabilities were observed in the strain measurements, which may reflect the complexity of CMFS load patterns and the sensitivity of strain values to gauge placement. This study supports the concept of hardware reduction, suggesting that two-point (or even one-point) fixation may provide sufficient stability for a ZMC fracture under applied muscle loading.

Management of zygomatico maxillary complex fractures

Zygomatic bone fractures should be effectively diagnosed and treated because they affect how the face is shaped for both aesthetically and functional reasons. It is possible to compare different surgical techniques and their comorbidities objectively through using outcome quantitative assessments, which call for a treatment programme and long-term follow-up. The purpose of this study was to compare the outcomes of two procedures and the effectiveness of the zygomatic bone following open reduction internal fixation (ORIF) employing two-point fixation and ORIF employing three-point fixation. Two groups of twenty patients each were randomly assigned to. Twenty patients in Group A had ORIF treatment using two-point miniplate fixation technique, and twenty patients in Group B received three-point miniplate fixation treatment. Differences between the two categories were ascertained after they had been evaluated in terms of their advantages and disadvantages. We discovered that the two-point fixation group had the fewest facial complications and neurological side effects. At 1 month follow up, Group B's average radiological evaluation score was 2.47± 0.30, and then at 6 months follow up, it was found out to be 1.87±0.47. A significant statistical distinction between the average radiological evaluations was observed in study participants of Group A at follow up done after one month and six months of procedure. Student's paired t- statistical test was utilized from this statistical analysis. (t = 6.54, P < 0.01). On carrying out follow up after one month of surgery, average neurological assessment score in study participants of group A was found out to be 0.22± 0.42, and then at 6 months follow up, it was 0.61±0.63. The average neurological evaluation score in study participants of Group A on carrying out follow up after one month of surgical procedure and and after six months of surgical procedure months showed a significant statistical distinction when utilizing Student's paired t- statistical test (t = 2.51, P = 0.021).It was determined that the best available rehabilitation for the treatment of zygomaticomaxillary complex fractures is open reduction and internal fixation employing two-point fixation by miniplates.

One-point versus two-point fixation in the management of zygoma complex fractures

Background

The treatment of zygoma complex fractures is of crucial importance in the field of plastic surgery. However, surgical methods to correct zygoma complex fractures, including the number of fixation sites, differ among operators. Although several studies have compared two-point and three-point fixation, no comparative research has yet been conducted on one-point versus two-point fixation using computed tomography scans of surgical results. Therefore, the present study aimed to address this gap in the literature by comparing surgical results between one-point and two-point fixation procedures.

Methods

In this study, we randomly selected patients to undergo surgery using one of two surgical methods. We analyzed patients with unilateral zygoma complex fractures unaccompanied by other fractures according to whether they underwent one-point fixation of the zygomaticomaxillary buttress or two-point fixation of the zygomaticomaxillary buttress and the zygomaticofrontal suture. We then made measurements at three points—the zygomaticofrontal suture, inferior orbital wall, and malar height—using 3-month postoperative computed tomography images and performed statistical analyses to compare the results of the two methods.

Results

All three measurements (zygomaticofrontal suture, inferior orbital wall, and malar height) showed significant differences (p<0.05) between one-point and two-point fixation. Highly significant differences were found for the zygomaticofrontal suture and malar height parameters. The difference in the inferior wall measurements was less meaningful, even though it also reached statistical significance.

Conclusion

Using three parameters in a statistical analysis of imaging findings, this study demonstrated significant differences in treatment outcomes according to the number of fixations. The results indicate that bone alignment and continuity can be achieved to a greater extent by two-point fixation instead of one-point fixation.