Surgical procedures
Advancing the entire midface in syndromic midface hypoplasia – with a comparison of external and internal distractors.
The Le Fort III osteotomy with subsequent distraction is the central procedure for correcting midface hypoplasia in syndromic craniosynostoses. The entire midface — cheekbones (zygoma), orbit and nasal bridge — is separated from the skull base and then advanced forward step by step over weeks (distraction osteogenesis).
The indication is primarily functional, not aesthetic:
Main affected syndromes: Crouzon, Apert, Pfeiffer (FGFR mutation). Occasionally Saethre-Chotzen.
Usually in late childhood (6–12 years), when sufficient bone mass is present. With acute functional urgency (severe airway obstruction, threatened corneal damage) the indication may be set earlier.
Stage 1 – surgery: Under general anaesthesia, Le Fort III osteotomies are performed: the entire midface is separated from the skull base along the orbital floors, zygoma and nasal bridge and mobilised. The distraction system is placed at the same time. Duration: approx. 4–6 hours; postoperative intensive care.
Stage 2 – distraction: After a latency phase of 5–7 days, advancement of about 1 mm per day. Over 3–6 weeks the midface is guided into the target position, then retention until bony consolidation and removal of the distractor.
External system (RED device): fixed to the skull with a halo frame and guided in front of the face. Advantage: full three-dimensional vector control throughout distraction — direction, extent and rotation can be adjusted at any time without further surgery. Engel et al. (J Craniomaxillofac Surg 2019) documented in Crouzon patients an SNA improvement from 76° to 86° (p=0.006), a tripling of the posterior airway space and stable long-term results.
Internal system: implanted buried, less burdensome for families in daily life. Disadvantage: the distraction direction is fixed by the implant axis and hardly correctable; an additional transfacial Kirschner wire is often required.
Besides correcting facial form, the improvement of the airway is the most important measurable goal: reduction or resolution of obstructive sleep apnoea, marked enlargement of the posterior airway space, permanent corneal protection. Definitive orthognathic fine correction after growth completion (from about 16–18 years) is often the final step.
Overview · Monobloc distraction · Crouzon · Apert · Adult care
It gradually moves the midface forward to improve breathing, eye protection and the bite. The extent is planned individually.
After surgery, the bone is slowly pulled apart using a distraction device, so that new bone forms. Treatment extends over several weeks and is closely monitored.