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Does Distraction Lower Risk of VPI Compared to Conventional Maxillary Advancement? A Retrospective Cohort Study of Adolescents with Cleft Palate.

OBJECTIVE
To determine whether method of maxillary advancement in adolescents with cleft palate with or without cleft lip (CP ± L) influences post-operative velopharyngeal function.


DESIGN
Retrospective cohort.


SETTING
Pediatric Tertiary Care Hospital.


PARTICIPANTS
One hundred and ninety-nine patients with CP ± L after LeFort I osteotomy for maxillary advancement at our institution between January 2007 and June 2019.


INTERVENTIONS
LeFort I osteotomy via distraction osteogenesis (DO) or conventional osteotomy (CO).


MAIN OUTCOME MEASURES
Patients who underwent DO or CO were compared for the presence of new velopharyngeal insufficiency (VPI), as measured by perceptual rating by a craniofacial speech-language pathologist.
Of the 199 patients who underwent maxillary advancement, 126 were available for analysis. The DO group was younger, male, and had more severe maxillary hypoplasia. Following surgery, 17/41 (41.5%) of the DO group had new VPI, compared to just 23/85 (27.1%) of the CO group. After adjusting for cleft type and predicted maxillary advancement, however, there was not sufficient evidence to reject the null hypothesis of no difference in risk of post-operative VPI between the two surgical groups (prevalence ratio [PR] 1.40, 95% CI 0.68-2.90). Increased prevalence of VPI after DO versus CO was primarily observed among patients with a pre-operative velopharyngeal need ratio < 0.8 (PR = 2.01, 95% CI 0.79-5.10) and patients with normal velopharyngeal function pre-operatively (PR = 2.86, 95% CI 0.96-8.50).
Our results suggest an increased rather than decreased risk of VPI following DO relative to CO. This association is primarily seen among those with a smaller velopharyngeal ratio or perceptually normal velopharyngeal function pre-operatively.