(12) Beyond the Airway: Feeding Challenges and Weight Trajectories Following Mandibular Distraction Osteogenesis for Robin Sequence

Abstract:

Background: Mandibular distraction osteogenesis (MDO) effectively treats airway obstruction in patients with Robin Sequence (RS), while promoting structural changes that facilitate more efficient feeding mechanisms and promote growth in infancy. Many children still require supplementation via gastrostomy tubes (G-tubes) and/or parenteral nutrition. Additionally, the temporal pattern of weight gain following MDO is poorly understood, particularly in the context of syndromic RS. The purpose of this study was to evaluate predictors of nutritional supplementation and weight trajectories of patients with syndromic and non-syndromic RS post-MDO.

Methods: A retrospective review was conducted of RS patients who underwent MDO at a major children’s hospital from May 2004 to November 2023. Those with less than 1 year of follow-up were excluded. Demographics, syndromic diagnoses, and feeding routes were collected. Weight-for-length (WFL) percentiles were recorded at birth, at time of MDO, and at 1, 3, 6, and 12 months postoperatively. Observed and expected average daily weight gain (ADWG) were calculated using each patient’s nearest standardized weight-for-length growth curve from their birth percentile. The percent difference between observed and expected ADWG was determined, with a positive value indicating greater weight gain than expected.

Results: A total of 94 patients met inclusion criteria (20 in syndromic RS cohort, 74 in isolated RS cohort). Median corrected gestational age was 1.0 month at time of MDO surgery. Overall, 41.5% received a G-tube within the study period. Full oral intake was achieved at a median of 39 days post-MDO. Patients with syndromic RS required more time to achieve full oral intake than those with isolated RS (55 days vs 37 days, P = .039). Multivariable logistic regression revealed greater odds of G-tube placement in patients with sRS (P = .011) and those born preterm (P = .002). Initial mean WFL percentiles decreased from birth to time of MDO, but increased to above 50th percentile by 12 months post-MDO. At 12 months post-MDO, the syndromic RS cohort had significantly lower mean WFL percentiles (P = .001). Despite this, the ADWG percent differences did not vary between syndromic and isolated RS cohorts from MDO to 12 months postoperatively (P = 0.49).

Conclusions: This study revealed significant improvements in oral intake and weight gain in patients with RS who underwent MDO, with both isolated and syndromic RS patients demonstrating positive growth trajectories. However, patients with syndromic diagnoses and preterm birth had greater G-tube requirements and required more time to achieve full oral intake. While those with syndromic RS exhibited lower WFL percentiles postoperatively, their growth aligned with expected ADWG, suggesting that with appropriate support, favorable outcomes are attainable in this population. Ultimately, tailored postoperative nutrition plans and close monitoring are critical for high-risk patients, particularly those with syndromic RS. These findings provide valuable insights and will aid physicians in counseling families on anticipated feeding and growth trajectories for patients with RS following MDO.
Figure 1. Probability of Achieving Full Oral Intake after MDOFigure 2. Weight Gain in Patients with Syndromic versus Isolated Robin Sequence Over Time