Box osteotomy

• Used for patients with hypertelorism and normal midface width.
  
• Through a coronal approach, osteotomies are made around each orbit.
  
• Nasal bones and ethmoid sinus are removed, and the orbits moved medially towards each other.
  
  
  
  • Alternatively, two paramedian segments are resected, which preserves the nasofrontal junction and cribriform plate.
  
  
• Rigid fixation is achieved with plates and screws.

Facial bipartition

• This procedure is well-suited to treat an inverted V deformity of maxillary occlusion.
  
• Orbital osteotomies leave the floor in continuity with the maxilla.
  
• Osteotomy through the midincisor line allows medial rotation/transposition.
  
• An occlusal splint ensures proper positioning of the maxilla.
  
• Rigid fixation, augmented with bone graft, holds the reduction.

Medial canthopexy

• Osteotomies usually result in detachment of the medial canthal ligament.
  
• If not reattached, canthal drift gives the appearance of recurrence of the hypertelorism.

Apert’s syndrome

• Occurs once in 160,000 live births.
  
• Most cases are sporadic but can be autosomal dominant.
  
• Clinical features:
  
  
  
  • Bicoronal synostosis
    
  • Exorbitism with hypertelorism
    
  • Downslanting palpebral fissures
    
  • Midface hypoplasia
    
  • Small, beaked nose
    
  • Class III malocclusion
    
  • CP in 20% of cases
    
  • Complex syndactyly of both hands and feet.
  
  
• The hand deformity is classified as:
  
  
  
  • Type I: little finger and thumb are separate.
    
  • Type II: only the thumb is separate.
    
  • Type III: all fingers are fused and share a common nail.
  
  
• There may be nonprogressive ventriculomegaly, but hydrocephalus is uncommon.
  
• Some have delayed mental development, but many develop normal intelligence.
  
• Conductive hearing loss is common.
  
• Cardiac and genitourinary abnormalities found in up to 10% of cases.

Crouzon’s syndrome

• Affects one in 25,000 live births.
  
• Most are autosomal dominant but can occur sporadically.
  
• Clinical features:
  
  
  
  • Bicoronal synostosis, although other sutures may be involved
    
  • Midface hypoplasia with significant exorbitism
    
  • Normal hands
    
  • High palatal arch; occasional CP
    
  • Class III malocclusion
    
  • Conductive hearing loss.
  
  
• Progressive hydrocephalus, often associated with chronic tonsillar herniation.
  
• In the absence of raised ICP, developmental delay is rare.

Saethre–Chotzen syndrome

• Estimated to affect one in 50,000 live births.
  
• Caused by mutations in the TWIST gene (autosomal dominant).
  
• Clinical features:
  
  
  
  • Bicoronal synostosis
    
  • Low-set hair line
    
  • Eyelid ptosis
    
  • Small, posteriorly displaced ears with prominent crura
    
  • Partial syndactyly of the second and third digits is often seen.
  
  
• Intelligence is usually normal, but some have mild impairment.

Pfeiffer’s syndrome

• Rare; inherited as an autosomal dominant trait.
  
• Craniofacial appearance is similar to that of Apert’s.
  
• A severe form of Pfeiffer’s is characterised by Kleeblattschädel deformity and profound CNS abnormalities.
  
• Otherwise, intelligence is usually normal.
  
• Hallmark feature is broad great toes and thumbs.

Muenke’s syndrome

• Discovered in 1996; also known as FGFR3-associated coronal synostosis.
  
• Differs from other syndromic synostoses because it is defined by a genetic test (Pro250Arg mutation) rather than a constellation of symptoms and signs.
  
• Affects one in 30,000 and inherited as an autosomal dominant trait.
  
• Coronal sutures are specifically involved; appearances are otherwise largely normal.
  
• Hearing loss (30%) and learning difficulties (10%) may occur.
  
• Reoperation is required more often than with other syndromic synostoses.

Carpenter’s syndrome

• Very rare autosomal recessive condition.
  
• Various sutures may be involved, commonly sagittal and coronal.
  
• Intelligence is usually impaired.
  
• Congenital cardiac abnormalities seen in ⅓ of cases.
  
• Obesity is typical.
  
• Clinical features:
  
  
  
  • Partial syndactyly of the fingers.
    
  • Preaxial polydactyly of the feet.

Sagittal strip craniectomy

• A longitudinal strip of bone over the suture is excised.

Fronto-orbital advancement and anterior cranial vault reconstruction

• The fronto-orbital bar is advanced and held with miniplates.
  
  
  
  • This increases the AP dimension of the skull.
    
  • Also deepens the upper orbits, improving exorbitism.
  
  
• The remaining frontal bone is sectioned and replaced in the desired shape.

Posterior cranial vault reconstruction

• Distraction osteogenesis is being used more frequently, given the higher incidence of severe bleeding with posterior vault remodelling.

Le Fort III osteotomy

• Performed to correct midface retrusion encountered in syndromal synostosis.
  
• May be performed early, aiming to become independent of tracheostomy or ameliorate severe obstructive sleep apnoea.

Monobloc advancement

• Advances the fronto-orbital and Le Fort III segments as one block.
  
• Associated with higher infection rates and greater blood loss, likely due to communication between cranial and nasal cavities.

Le Fort I osteotomy

• Addresses class III malocclusion and anterior open bite, commonly seen with midface hypoplasia.
  
• Planned to coincide with completion of orthodontic treatment, at the time of skeletal maturity.

Skeletal distraction

• Many skeletal manipulations are now done by distraction, including:
  
  
  
  • Le Fort I
    
  • Posterior cranial vault
    
  • Le Fort III
    
  • Monobloc
    
  • Mandible.
  
  
• Osteotomies are made as usual.
  
• A distraction device is fitted either internally or externally.
  
• As the bone is distracted, the soft tissues are gradually stretched over several weeks.
  
  
  
  • Greater advancement can be achieved with distraction than by single-stage advancement.
  
  
• Once the desired advancement is achieved, further surgery may be required to stabilise the bones with plates and screws.
  
  
  
  • If not, a prolonged period of consolidation is required with the distractor in place.

Classification

• The following classifications of hemifacial microsomia have been described:
  
• OMENS classification
  
  
  
  • This classifies deformities of the Orbits, Mandible, Ear, Facial Nerve and Soft tissue.
  
  
• Pruzansky classification of the mandible:
  
  
  
  • Type I: mild ramus hypoplasia, the body is minimally affected.
    
  • Type IIa: ramus and condyle hypoplasia, but the glenoid–condyle relationship is maintained.
    
  • Type IIb: as for type IIa but with a nonarticulating temporomandibular joint (TMJ).
    
  • Type III: the ramus is very thin or absent with no evidence of a TMJ.
    
    
    
    • Mulliken and Kaban subdivided Pruzansky type II as shown.
  
  
• Meurman classification of the ear:
  
  
  
  • Grade I: small, malformed auricle, but all components present.
    
  • Grade II: vertical remnant of cartilage and skin; atresia of the external meatus.
    
  • Grade III: total or near-total absence of the auricle.
  
  
• SAT classification
  
  
  
  • Proposed by David, it is analogous to the TNM system used in cancer staging.
    
  • It grades the Skeletal, Auricular and soft Tissue anomalies and suggests a treatment plan.

Treatment

• Should be individualised to the patient.
  
• Abnormalities in other organ systems should be sought.
  
• The following is a general guide:

Before 2 years

• Remove any auricular appendages.
  
• Correct macrostomia with a commissuroplasty.
  
• Fit hearing aids.
  
• Occasional involvement of the fronto-orbital region may require fronto-orbital advancement.

Between 2 and 6 years

• Distraction of the mandibular ramus.
  
• Pruzansky III deformities may require formal reconstruction of the mandibular ramus.
  
  
  
  • This is usually performed with a costochondral rib graft.

Between 6 and 14 years

• Orthodontic treatment.
  
• Ear reconstruction.
  
• Soft tissue augmentation:
  
  
  
  • Free tissue transfer
    
  • Fat grafting.

After 14 years

• Augmentation of deficient areas of the facial skeleton.
  
  
  
  • Can be done using bone grafts or alloplastic implants, e.g. Medpor^®.
  
  
• Orthognathic surgery (OGS).

Clinical features

• Bilateral symmetrical abnormalities of the first and second branchial arches.
  
• Characteristic convex facial profile.
  
  
  
  • Prominent nasal dorsum and retrusive lower jaw and chin.
  
  
• Average or above-average intelligence is the norm.
  
• Typically, abnormalities are present in the following sites:

Eyes

• Part of the lateral canthus and lower eyelid may be absent (coloboma).
  
• Eyelashes are often absent medially.
  
• Atrophic tarsal plate.
  
• Medially displaced lateral canthus.
  
• Absent lacrimal apparatus.
  
• Antimongoloid slant of the palpebral fissure.
  
• Hypoplastic lateral orbits.

Nose

• Moderately wide bridge with mid-dorsal hump.
  
• Drooped tip that lacks projection.

Cheek

• The zygoma may be hypoplastic, clefted through the arch or absent.
  
• A depression may run between the corner of the mouth and angle of the mandible, along the line of a Tessier 7 cleft.

Palate

• CP, with or without CL, occurs in 30% of cases.
  
• There may be associated choanal atresia.
  
• If not, the palate is usually high-arched.

Maxilla and mandible

• The ramus of the mandible is often short.
  
• TMJ and muscles of mastication may be hypoplastic or absent.
  
• Class II malocclusion with anterior open bite.

Ear

• May be small (microtia) or buried under the skin (cryptotia).
  
• External meatus may be hypoplastic.
  
• Middle ear deformities include missing ossicles or cavities.

Cranium

• Reduced cranial base angle (basilar kyphosis).
  
• Although synostosis is not a feature, the skull may have abnormally short AP length and bitemporal width.

Treatment

Airway

• Patients often have difficulty maintaining their airway due to maxillary and mandibular hypoplasia.
  
  
  
  • Tracheostomy may be required.
  
  
• Nursing them in a prone position can help improve their oxygen saturation.
  
• Increased risk of airway obstruction following CP repair.

Feeding

• Factors affecting the airway can also affect swallowing and feeding.
  
• Failure to thrive requires supplemental tube feeding.

Zygoma and orbit

• Calvarial bone graft can be used to augment the orbital floor and zygoma.
  
• Lateral canthopexy is done through the same bicoronal incision.
  
• Usually performed when the child is >7 years, when bony development in that region is almost complete.

Mandible

• Mandibular deformity may be corrected with:
  
  
  
  • Rib grafts
    
  • Mandibular advancement
    
  • Bimaxillary procedures
    
  • Le Fort I osteotomy and orthodontic treatment
    
  • Distraction
    
  • Genioplasty
    
  • TMJ reconstruction with costochondral graft (Pruzansky III).
  
  
• Usually performed at early skeletal maturity, between 13 and 16 years.

Ear

• Reconstruction of the external ear may be required.
  
• Middle ear surgery is postponed until after auricular reconstruction, to preserve soft tissues.
  
• Hearing deficits can be improved with hearing aids.

Nose

• Rhinoplasty involves:
  
  
  
  • Open approach
    
  • Osteotomies
    
  • Dorsal hump reduction
    
  • Cephalic trim of the lower lateral cartilages
    
  • Columella strut to improve tip projection.
  
  
• This is done following any OGS.

Treatment

• Immediate life-saving airway management involves turning the newborn prone to relieve glossoptosis.
  
• If unsuccessful, a nasopharyngeal airway (NPA) can be inserted to bypass the obstruction caused by the tongue.
  
• PRS has been classified by severity by the Cleft service at Birmingham Children’s Hospital, UK.
  
• This classification is also used to guide treatment:
  
  
  
  • Grade 1: Nursed side-to-side only.
    
  • Grade 2: Requires nasogastric (NG) feeding and nursed side-to-side.
    
  • Grade 3: Requires NPA, NG feeding and nursed side-to-side.
  
  
• Once stabilised and gaining weight, all PRS babies are discharged with an oxygen saturation monitor.
  
• A cleft specialist nurse closely monitors weight gain.
  
• Parents and other carers are trained to manage NG feeds and the NPA.
  
  
  
  • Also trained in Paediatric Basic Life Support prior to discharge.
  
  
• Birmingham Children’s Hospital successfully treats all PRS babies this way.
  
• Other more invasive treatments include:
  
  
  
  • Glossopexy (tongue–lip adhesion)
    
  • Tracheostomy
    
  • Subperiosteal release of the floor of the mouth
    
  • Distraction osteogenesis of the mandible
    
    
    
    • Distraction osteogenesis carries a low but quantifiable mortality rate.
  
  
• Some surgeons maintain that a proportion of severely affected PRS babies require surgical intervention, but that view is controversial.
  
• PRS may present with other syndromes and anomalies.
  
  
  
  • All PRS babies should be screened for Stickler’s syndrome.
    
    
    
    • There is a risk of retinal detachment, preventable by early intervention.

Clinical features

• Characterised by gradual wasting of one side of the face and forehead.
  
• Usually starts between 5 years and late teens.
  
• Female to male ratio is 1.5:1.
  
• Involves skin, soft tissue and bone.
  
• Muscle involvement can also include atrophy of the tongue and palate.
  
• Typically progresses within the dermatome of one or more divisions of the trigeminal nerve.
  
• Wasting continues for a number of years before gradually stopping.
  
• The result is permanent tissue deficiency on one side of the face.
  
• The following may be seen:
  
  
  
  • Localised atrophy of the skin with pigment changes
    
  • Change of hair colour or alopecia
    
  • Change of iris colour and enophthalmos
    
  • A sharp depression on the forehead, occasionally extending into the hairline
    
    
    
    • This early sign is known as ‘coup de sabre’
    
    
  • Atrophy of cheek bone and soft tissue
    
  • Malocclusion.

Treatment

• Generally, no treatment is performed while the condition is active and progressive.
  
• Short-term improvements may be achieved with injectable fillers.
  
• Reconstruction is performed once the condition has been stable for about 12 months.
  
  
  
  • This is judged by serial photographs.
  
  
• Reconstructive options include:
  
  
  
  • Fat and dermofat grafts
    
  • Cartilage grafts
    
  • Le Fort I osteotomy
    
  • Genioplasty
    
  • Alloplastic augmentation
    
  • Temporoparietal fascia and temporalis muscle transfers
    
  • Free tissue transfer.
    
  • Adipofascial flaps are preferred over muscle flaps due to the atrophy of muscle over time.

Classification

1. Monostotic, with single bone involvement.
   
   
   
   • Craniofacially, it usually affects frontal bone, sphenoid or maxilla.
     
   • Can also affect ribs, femur or tibia.
   
   
2. Polyostotic, with multiple bone involvement.
   
   
   
   • Approximately 3% have the triad of McCune–Albright syndrome:
     
     
     
     • Polyostotic fibrous dysplasia
       
     • Precocious puberty
       
     • Café-au-lait macules.

• Hyperthyroidism and tumours of the pituitary gland may also be found.
  
• Cherubism is a rare autosomal dominant condition, also known as familial fibrous dysplasia.
  
  
  
  • Characterised by multiple areas of fibrous dysplasia within the mandible and maxilla.
    
  • Self-limiting and regresses spontaneously, leaving no deformity.

Treatment

• Early intervention is required when function is at risk:
  
  
  
  • Optic nerve compression or other nerve palsies
    
  • Diplopia
    
  • Malocclusion.
  
  
• Surgery involves resection of the abnormal areas.
  
• The resultant defects can be reconstructed with calvarial bone grafts or alloplastic implants.
  
• Free tissue transfer is used to fill postresection dead space.
  
• Some cases have responded to bisphosphonate therapy.

Classification

• Many types have been described; only two forms are commonly encountered:

Neurofibromatosis type 1 (NF1)

• Also known as von Recklinghausen’s disease.
  
• The most common type (90%), affecting one in 3000 births.
  
• The mutated gene is on chromosome 17.
  
• Two of the following clinical features are required for diagnosis:
  
  
  
  • Six or more café-au-lait macules (>0.5 cm in children; >1.5 cm in adults)
    
  • Two or more neurofibromas or one plexiform neurofibroma
    
  • Axillary or inguinal freckling
    
  • Optic glioma
    
  • Two or more Lisch nodules (hamartomas of the iris)
    
  • A distinctive osseous lesion with cortical thinning or dysplasia
    
  • A first-degree relative with NF1.
  
  
• NF1 is associated with orthopaedic complications, including:
  
  
  
  • Scoliosis or kyphosis of the spine
    
  • Congenital bowing and pseudarthrosis of the tibia and forearm.

Neurofibromatosis type 2 (NF2)

• Also known as central neurofibromatosis.
  
• Affects approximately one in 25,000 live births.
  
• The mutated gene is on chromosome 22.
  
• Characterised by bilateral vestibular schwannomas.
  
• Other abnormalities include:
  
  
  
  • Intracranial meningiomas
    
  • Spinal tumours (usually schwannomas or meningiomas)
    
  • Peripheral nerve schwannomas
    
  • Ocular abnormalities (posterior subcapsular lenticular opacities).

Malignancy

• Lifetime risk of malignant transformation is <10%.
  
• Malignant peripheral nerve sheath tumours (MPNST) arise from Schwann cells.
  
  
  
  • Usually occur in plexiform neurofibromas.
  
  
• Pain and rapid growth are indicators of malignant degeneration.
  
  
  
  • Positron emission tomography (PET) scanning can help localise the malignancy.
  
  
• Metastases are common.
  
• An aggressive surgical attempt at total excision is undertaken.
  
• 5-year survival following MPNST is approximately 16–52%.

Treatment

• Treatment of plexiform neurofibromas requires a multidisciplinary team (MDT) approach.
  
• Trials are underway looking at imatinib for treatment of plexiform neurofibromas.
  
• However, surgery is currently the mainstay of treatment.
  
• The following should be considered:
  
  
  
  • Timing and extent of surgery
    
  • Strategies to deal with bleeding refractory to conventional electrocautery:
    
    
    
    • Hypotensive anaesthesia, invasive monitoring and cell salvage
      
    • Some advocate packing the wounds open with direct compression.
      
      
      
      • Delayed closure then takes place after 48 hours.
  
  
• There is a balance between an acceptable aesthetic outcome and preserving function.
  
  
  
  • The limits of surgery should be discussed with the patient.
  
  
• Surgery addresses the deformity only; recurrence is usual.
  
• Improvements are temporary because skin involved with neurofibroma lacks elasticity.
  
• Specific craniofacial problems associated with NF1 include:

Orbitopalpebral neurofibromas

• Associated with dysplasia of the sphenoid wing.
  
  
  
  • Allows the temporal lobe to herniate into the orbit.
  
  
• The bony orbit is enlarged, with pulsatile exophthalmos.
  
• If vision is preserved in the affected eye, the neurofibroma is debulked.
  
• The orbit can be approached through:
  
  
  
  • The upper eyelid for mild lesions
    
  • A bicoronal skin incision with osteotomy into the lateral orbit
    
  • A combined craniofacial approach with frontal craniotomy.
  
  
• The sphenoid wing is reconstructed using split rib or calvarial bone graft.
  
• If vision is impaired, orbital exenteration is performed.
  
  
  
  • The eyelid is used for skin cover to allow the orbit to take a prosthesis.

Plexiform neurofibromas of the facial soft tissues

• Cause distortion of the facial soft tissues and skeleton.
  
  
  
  • Deformities can lead to visual loss.
  
  
• Bony defects are tackled first, with correction of the occlusal plane.
  
• Soft tissues are reconstructed with free tissue transfer or dermal-fascial-fat grafts.
  
• Tissue redundancy is addressed through a facelift incision or Weber–Ferguson approach.
  
• Techniques to minimise recurrence of soft tissue ptosis include:
  
  
  
  • Anchoring tissue to bone
    
  • Fascia lata slings.

Nasal dermoid cysts

• Approximately 10% of dermoids are located on the nose.
  
  
  
  • Have a different origin to other dermoids and warrant investigation.

Embryology

• Frontal and nasal bones are separated by a small fontanelle – the fonticulus nasofrontalis.
  
• A prenasal space exists between the skull base and nasal tip.
  
• Dura extends through the fonticulus into the prenasal space, where it contacts skin.
  
• With facial growth, the dura separates from the skin and recedes.
  
  
  
  • At this time, the fonticulus nasofrontalis and foramen cecum fuse, forming the cribriform plate.
  
  
• Nasal dermoids and sinuses are formed when the dura fails to separate from skin.
  
  
  
  • As the dura retracts intracranially, it pulls ectodermal tissue with it.
  
  
• Nasal or midline dermoids should be imaged to rule out intracranial extension.
  
  
  
  • CT may show a bifid crista galli and patent foramen cecum.
    
  • MRI further demonstrates the extent of intracranial involvement.

Treatment

• A combined craniofacial approach with a neurosurgeon.
  
• The entire cyst can sometimes be removed through a frontal craniotomy.
  
• Alternatively, it can be approached by direct incision around the cyst or open rhinoplasty.
  
  
  
  • The stalk is traced superiorly, between the cartilaginous septum and nasal bones.
    
  • If the stalk is not excised, craniotomy is required to ensure complete removal.
    
  • Incomplete excision can lead to infection and osteomyelitis.