Mandibular distraction osteogenesis: at what age to proceed

Craniofacial Distraction Osteogenesis

Distraction osteogenesis (DO) of the craniofacial skeleton has become an effective technique for the treatment of both nonsyndromic and syndromic conditions. The advent of craniofacial DO has allowed for earlier intervention in pediatric patients with less complication risk and morbidity compared to traditional techniques. In this review, we will discuss current application and technique for craniofacial DO by anatomical region and explore future applications in craniofacial surgery.

Complications of Mandibular Distraction Osteogenesis in Infants with Isolated Robin Sequence

Mandibular Distraction Osteogenesis (MDO) is now the preferred procedure to alleviate airway obstruction in infants with severe Robin Sequence (RS). However, there have been very few studies investigating complications related to MDO surgery performed on patients affected by isolated RS. In this study, age at distraction, weight at distraction, preoperative intubation, repeat MDO and complications associated with MDO were included as variables. Minor, moderate and major problems were evaluated and recorded as surgical site infections (SSI), injuries to the facial nerve, self-extinction hypertrophic scars, temporomandibular joint ankylosis, device failures, early ossification and fibrous non-union. One hundred and fifty one patients with isolated RS were included. At distraction, the mean age was 72 days (12-540 days) and the mean weight was 4.05 kg (2.4-12.2 kg). Only one patient needed tracheostomy after MDO, and none required further distraction. Ultimately, the complication rate was 15.23%, and there was a total of 7.95% minor, 9.27% moderate and 0% major complications. Minor incidents included surgical site infection (SSI) managed with antibiotics taken orally (n = 8), neuropraxia in the VII cranial nerve (CN) (n = 1), and hypertrophic scarring (n = 3). Incidents reported as moderate were SSIs managed with intravenous antibiotics (n = 9), incision and drainage (n = 3) and self-extubation (n = 2). There was no case of TMJ ankylosis. There were no cases of early or premature ossification, fibrous non-union and device fracture. In conclusion, MDO is an effective and appropriate management technique for infants with isolated RS and severe airway obstruction. Infections at the surgery site accounted for the vast majority of the complications. Further investigations may be needed to determine the long-term consequences of MDO.

Non-Surgical Respiratory Management in Relation to Feeding and Growth in Patients with Robin Sequence; a Prospective Longitudinal Study

OBJECTIVE

To reflect upon our non-surgical respiratory management by evaluating clinical outcomes regarding airway, feeding, and growth during the first year of life in patients with Robin Sequence.

DESIGN

Prospective study.

SETTING

Sophia Children's Hospital, Rotterdam, the Netherlands.

PATIENTS/ PARTICIPANTS

36 patients with Robin Sequence who were treated between 2011 and 2021.

INTERVENTIONS

Positional therapy and respiratory support.

MAIN OUTCOME MEASURE(S)

Data on respiratory outcomes included polysomnography characteristics and capillary blood gas values. Feeding outcomes were based on the requirement of additional tube feeding. Outcomes on growth were expressed as standard-deviation-scores (SDS) for weight-for-age (WFA) and height-for-age (HFA).

RESULTS

Twenty patients were treated with positional therapy (PT), whilst the other 16 patients required respiratory support. Twenty-two patients presented with non-isolated Robin Sequence (RS). During the first year of life, obstructive apnea hypopnea index decreased, oxygen levels enhanced, and capillary blood gas values improved. Eighty-six percent (31/36) experienced feeding difficulties, which completely resolved in 71% (22/31) during their first year of life. From start treatment, to stop treatment, to the age of 1 year, the SDS WFA worsened from -0.40 to -0.33 to -1.03, respectively.

CONCLUSIONS

Non-surgical respiratory treatment resulted in an improvement of respiratory outcomes to near normal during the first year of life in patients with RS. These patients often experience feeding difficulties and endure impaired weight gain up to 1 year of age, despite near normalization of breathing. The high prevalence of feeding difficulties and impaired weight for age indicate the urgency for early recognition and adequate treatment to support optimal growth.

Mandibular distraction to correct severe non-isolated mandibular hypoplasia: The role of drug-induced sleep endoscopy (DISE) in decision making

OBJECTIVES

In patients with mandibular hypoplasia, mandibular distraction osteogenesis (MDO) aims to relieve tongue-based airway obstruction. Drug-induced sleep endoscopy (DISE) provides a dynamic assessment of the upper airway and visualizes anatomical site and cause of airway obstruction. The aim of this study was to evaluate the effect of MDO on tongue-based airway obstruction found by DISE within a non-isolated patient population with severe upper airway obstruction (UAO). Furthermore, we aimed to assess the additional value of DISE in clinical decision making by correlating DISE findings to functional airway outcomes after MDO.

METHODS

Findings on DISE in children who underwent MDO were retrospectively gathered and evaluated. According to DISE findings, severity of tongue-based obstruction was scored using a 4-step classification similar to the one that is used by Bravo et al.. Intubation conditions were scored according to the Cormack Lehane score (CLS). Pre-and postoperative DISE findings were compared and correlated with functional airway outcomes following MDO.

RESULTS

In 19 out of 28 MDO procedures, both a pre-and postoperative DISE was available. Tongue-based obstruction scores improved in 13 procedures, which correlated to a functional improvement in seven. Postoperative tongue-based obstruction differed significantly between patients with successful MDO and patients treated unsuccessfully (2.00 ((Interquartile range (IQR) 1.00-2.00) vs. 3.00 (IQR 2.00-4.00), p = 0.028), whereas this difference was not significant for the CLS (1.00 (IQR 1.00-1.50) vs. 2.00 (IQR 1.00-4.00), p = 0.066). If no improvement of tongue-based obstruction was seen, MDO is very unlikely to be successful on the functional airway.

CONCLUSIONS

DISE provides information on the site and nature of airway obstruction and can visualize the effect of MDO on the severity of tongue-based airway obstruction. Therefore, it can be of additional value in understanding the differences in functional airway outcomes after MDO and aids in deciding appropriate and targeted treatment. Hence, standardized use of DISE, in addition to the clinical assessment of mandibular position and a polysomnography, during MDO management is highly recommended.

Decannulation and Airway Outcomes With Maxillomandibular Distraction in Treacher Collins and Nager Syndrome

BACKGROUND

Treacher Collins syndrome is a rare disorder (1/50,000 live births) with features that include hypoplastic orbitozygomatic complex with downward slanting eyes, and maxillary/mandibular retrusion. Obstructive sleep apnea and tracheostomy-dependence are common. This study presents the outcomes of skeletal distraction on avoidance of tracheostomy and decannulation in this patient population.

METHODS

The authors reviewed charts of all patients with Treacher Collins syndrome who underwent craniofacial reconstruction from 2003 to 2016. Primary outcome measures included decannulation of tracheostomy dependent patients and avoidance of tracheostomy. Secondary outcome measures included cephalometric parameters, polysomnography scores, and airway exposure scores on direct laryngoscopy.

RESULTS

Twenty-five patients underwent mandibular and maxillary advancement to resolve upper airway obstruction. Mandibular distraction was performed in 24 of 25 patients, and maxillary distraction in 14 of 25 patients. Maxillary distraction was combined with mandibular distraction in 13 of 17 to accomplish greater advancement and counter-clockwise rotation of the entire maxillary-mandibular complex. Six of 7 patients, 85.7%, avoided a tracheostomy and 39% (7 of 18) were decannulated. Cephalometric changes in sella-nasion-A point, sella-nasion-B , occlusal plane angle, and posterior airway space were equivalent between the groups who were able to clear their obstruction and those who were not.

CONCLUSIONS

Treacher Collins is a very challenging disease in which to resolve airway obstruction. Thus, thorough evaluation of the entire airway for all levels of obstruction is critical to successful outcomes. Future collaborative efforts between multiple institutions can help to increase our understanding and effective management of this rare disease.

The role of curvilinear distraction system in pediatric obstructive sleep apnea: A case report

OBJECTIVE

The authors present a case of obstructive sleep apnea associated with severe mandibular micrognathia treated by mandibular bone distraction with curvilinear system planned under computer assistance.

CLINICAL PRESENTATION

A 15-year-old child with limited compliance to continuous positive airway therapy was referred to the authors' department. Observation revealed severe mandibular micrognathia as the major cause for obstructive sleep apnea syndrome. The first polysomnography study revealed 14 obstructive apneas, 16 obstructive hypopneas, and 4.6/h apnea-hypopnea index.

CONCLUSION

Mandibular distraction osteogenesis can be a successful technique in alleviating upper airway obstruction secondary to micrognathia, while also improving the patient's appearance. Surgical planning under computer assistance is a useful tool to predict bone movements, and curvilinear distraction could be considered valuable in mandibular distraction.

Outcome following Surgical Interventions for Micrognathia in Infants with Pierre Robin Sequence: A Systematic Review of the Literature

Background

Tongue-lip adhesion (TLA), mandibular distraction osteogenesis (MDO), and subperiosteal release of the floor of the mouth (SPRFM) are the most commonly performed surgical procedures to treat severe airway obstruction in infants born with Pierre Robin sequence (PRS).

Objectives

To determine the rate of failure of each type of procedure, in terms of mortality and the need for tracheostomy, and to determine what proportion of infants have significant airway obstruction postoperatively as determined by polysomnography (PSG) and compare the data by procedure type.

Method

A comprehensive literature search (1981 through June 2015) was done of the National Library of Medicine database using PubMed. Extracted data included diagnosis, type of surgery, and outcome including mortality, need for postoperative tracheostomy and details of PSG. Persistence of significant airway obstruction was defined as an apnea-hypopnea index > 15 events/h on PSG.

Results

Both mortality rate and need for tracheostomy were low for all procedures. Many studies lacked sufficient detail to identify significant airway obstruction postoperatively. In studies with sufficient data, MDO was associated with the lowest percentage of significant airway obstruction postprocedure (3.6%) compared to 50% for infants who underwent TLA. Insufficient PSG data was available for patients who were treated with SPRFM.

Conclusions

There is a paucity of objective PSG data to definitively assess postoperative airway outcomes for PRS. MDO appears to be the most effective technique based on the available PSG data. Standardized use of PSG may lead to better identification and treatment of patients at risk for suboptimal airway outcomes postoperatively.

Numerical modeling of the traction process in the treatment for Pierre-Robin Sequence

INTRODUCTION

The goal of this numerical study was to identify the results of modulated growth simulation of the mandibular bone during traction in Pierre-Robin Sequence (PRS) treatment.

METHODS

Numerical simulation was conducted in the Ansys 16.2 environment. Two FEM (finite elements method) models of a newborn's mandible (a spatial and a flat model) were developed. The procedure simulated a 20-week traction period. The adopted growth measure was mandibular length increase, defined as the distance between the Co-Pog anatomic points used in cephalometric analysis.

RESULTS

The simulation calculations conducted on the developed models showed that modulation had a significant influence on the pace of bone growth. In each of the analyzed cases, growth modulation resulted in an increase in pace. The largest value of increase was 6.91 mm. The modulated growth with the most beneficial load variant increased the basic value of the growth by as much as 24.6%, and growth with the least beneficial variant increased by 7.4%.

CONCLUSIONS

Traction is a simple, minimally invasive and inexpensive procedure. The proposed algorithm may enable the development of a helpful forecasting tool, which could be of real use to doctors working on Pierre-Robin Sequence and other mandibular deformations in children.

Effectiveness of Tongue-lip Adhesion for Obstructive Sleep Apnea in Infants With Robin Sequence Measured by Polysomnography

OBJECTIVE

Tongue-lip adhesion (TLA) is commonly used to relieve obstructive sleep apnea (OSA) in infants with Robin sequence (RS), but few studies have evaluated its efficacy with objective measures. The purpose of this study was to measure TLA outcomes using polysomnography. Our hypothesis was that TLA relieves OSA in most infants.

METHODS

This is a retrospective study of infants with RS who underwent TLA from 2011 to 2014 and had at least a postoperative polysomnogram. Predictor variables included demographic and birth characteristics, surgeon, syndromic diagnosis, GILLS score, preoperative OSA severity, and clinical course. A successful outcome was defined as minimal OSA (apnea-hypopnea index score < 5) on postoperative polysomnogram and no need for additional airway intervention. Descriptive, bivariate, and regression statistics were computed, and statistical significance was set at P < .05.

RESULTS

Eighteen subjects who had TLA at a mean age of 28 ± 4.7 days were included. Thirteen (72.2%) had a confirmed or suspected syndrome, and the mean GILLS score was 3 ± 0.3. All parameters trended toward improvement from the preoperative to postoperative polysomnograms, and improvement in OSA severity, oxygen saturation nadir, and arousals per hour was statistically significant (P < .02). This effect was significant across categories of surgeon, syndrome, and GILLS score. Nine subjects (50%) met the criteria for a successful outcome. Bivariate and regression analyses did not demonstrate a significant relationship between success and any predictor variable.

CONCLUSIONS

TLA improved airway obstruction in all infants with RS but resolved OSA in only nine patients, and success was unpredictable.

The effectiveness of mandibular distraction in improving airway obstruction in the pediatric population

BACKGROUND

Distraction osteogenesis is an effective technique for elongating the deficient mandible. The authors specifically evaluated its effectiveness in the treatment of airway obstruction in pediatric patients with mandibular hypoplasia.

METHOD

A comprehensive literature review of the National Library of Medicine (PubMed) database was performed. English-language studies involving isolated distraction of the pediatric mandible (younger than 18 years) with descriptive reporting of airway changes were included. Extracted data included demographics, initial diagnosis, distractor type, distraction protocol, predistraction and postdistraction airway status, and complications.

RESULTS

Seventy-four articles met the inclusion criteria, resulting in 711 patients with craniofacial abnormalities who underwent mandibular distraction osteogenesis. Mean age at the time of distraction was 18.1 months. The most common diagnoses were isolated Pierre Robin sequence (52.9 percent), syndromic Pierre Robin sequence (7 percent), and Treacher Collins syndrome (6.8 percent). Mandibular distraction osteogenesis successfully treated airway obstruction in 89.3 percent of cases. Success was defined as either decannulation of tracheostomy, avoidance of tracheostomy or continuous positive airway pressure, or alleviation or significant improvement of obstructive sleep apnea symptoms. One hundred seventy-one (84.2 percent) of the 203 tracheostomy-dependent patients were successfully decannulated. Among the 181 patients with obstructive sleep apnea, mandibular distraction osteogenesis successfully allowed for either complete resolution or significant improvement of symptoms in 95.6 percent. A 23.8 percent overall complication rate was noted. The mean follow-up time was 28.7 months.

CONCLUSION

In addition to its positive effect on facial appearance, mandibular distraction osteogenesis is an effective procedure for the treatment of airway obstruction associated with congenital craniofacial defects involving mandibular hypoplasia in appropriately selected patients.

Neonatal mandibular distraction osteogenesis: converting virtual surgical planning into an operative reality

Mandibular distraction osteogenesis (DO) has become an accepted method to manage severe cases of micrognathia-induced airway obstruction in neonates. Current imaging used to plan these procedures aids in surgical planning, but offers only a rough guide for the operating room. To our knowledge the following report offers the first description of virtual surgery used to guide DO in the mandible of a neonate. The plan provided a valuable link between the simulated procedure and the actual operative steps. Such technology can serve an important role in DO and offers objective guidance in device selection, vector planning and operative guide positioning.

Mandibular distraction osteogenesis in the micrognathic neonate: a review for neonatologists and pediatricians

In the past, severe neonatal upper airway obstruction secondary to micrognathia was managed with a tracheostomy. Although effective, tracheostomy can cause many short-term and long-term complications. More recently, mandibular distraction osteogenesis (MDO) has become a well-accepted surgical option in treating micrognathic newborns. Overall, MDO has been reported to be an effective intervention in alleviating the micrognathia-associated airway compromise. Furthermore, it seems to be well tolerated and has supplanted the need for tracheostomy in many patients. Neonatologists and pediatricians commonly care for these children, and therefore an up-to-date clinical narrative review regarding MDO is presented to increase the awareness of this relatively new surgical option.

The long-term effects of mandibular distraction osteogenesis on developing deciduous molar teeth

Background. Many studies have demonstrated the effectiveness of mandibular distraction osteogenesis (MDO) in alleviating the micrognathia-associated upper airway obstruction but very few studies have focused on long-term dental outcomes. Objective. To report the effect of MDO on developing deciduous molars in the distraction area. Methods. A retrospective chart review was performed to identify patients with Pierre Robin sequence who underwent MDO with documented long-term dental assessments. Results. Ten children (mean age at surgery 69.8 days; 6 boys and 4 girls) were included for analysis. All patients underwent bilateral MDO with an inverted L-shaped osteotomy to avoid injuring tooth buds. The dental developmental stage was primary dentition in all children. Overall, 3 patients developed minor dental problems involving 4 molar teeth (2 root malformations and 2 shape anomalies) but they did not require any interventions. Conclusion. Significant primary molar developmental complications were not seen in our patients. The use of internal distractor device with an inverted L-shaped osteotomy seems to be a safe surgical approach in regards to dental outcomes.