orthognathic complications
TRANSCRIPT
CONTENTS
• Presurgical• Intraoperative• Vascular• Neural• Unwanted fragmentation
• Post operative• Loss of vascularity : aseptic necrosis• Nose• Lip• Infection• Nonunion/delayed union• Occlusal disturbances• TMJ dysfunction• Relapse• Rare complications
“Unintended consequence of the surgery that causes harm to the patient, occurring either intra-operatively or early and late post-operatively.”
• A complication is so named because it complicates the situation.
• “No matter what measures are taken, doctors will sometimes falter, and it isn't reasonable to ask that we achieve perfection. What is reasonable is to ask that we never cease to aim for it.”
•― Atul Gawande, Complications: A Surgeon's Notes on an Imperfect Science
N = 1000 patients (1983-2002)
INTRA AND PERIOPERATIVE COMPLICATIONS OF THE LEFORT I INTRA AND PERIOPERATIVE COMPLICATIONS OF THE LEFORT I OSTEOTOMY: A PROSPECTIVE EVALUATION OF 1000 PATIENTSOSTEOTOMY: A PROSPECTIVE EVALUATION OF 1000 PATIENTS
Kramer; J CrFac Surg Vol 15,6 Nov’04
Incidence of complications and problems related to orthognathic surgery Incidence of complications and problems related to orthognathic surgery Su-Gwan Kim, Sun-Sik Park ; JOMS 65;2438-2444,2007
N = 301 (1998-2005)Neurosensory deficit - IAN - Commonest complication 73.3% - BSSO.Bleeding in Lefort I – most serious complication – Maxillary a.Inappropriate fragmentation - 5% - BSSO
SUMMARYSUMMARY
• Total range of Incidence of complications – 6.4-9.7%
• Complication rates: more - craniofacial deformities
• Commonest : paresthesia with IAN 36%- 91%
• Most serious – bleeding (immediate/delayed)
• Avg. infection rates :1.1%-4%
• Ischemic necrosis rare: more with multiple segmentation
CLASSIFICATIONCLASSIFICATION
Pre-surgical
Intra - operative
Post – operative
Dimitroulis 1998 J Adult Orthod Orthognath Surg
PRESURGICAL
Lack of pre treatment objectives
Laboratory errors
Orthodontics
Pre-surgical
Lack of pre-treatment objectives
• Failure to recognize underlying skeletal abnormality
• Unexpected adverse growth
• Lack of patient co-operation
• Gross skeletal deformity correction:
mainly orthodontics & minimal surgery
Inability to perform the ideal procedure
Undesired esthetic and occlusal results
Creation of new problems and revision procedures
Presurgical : Lack of pre treatment objectives
Unsatisfactory bite registration
Discrepancy in mounting the cast
Improper model surgery
Warpage of splints
Presurgical : Laboratory errors
• Insufficient decompensation
• Inadequate transverse coordination
• Uncorrected tooth size problems
• Inadequate preoperative root divergence in segmental surgery
• Active orthodontic wires at surgery
• Orthodontic appliances
Presurgical : Orthodontics
Presurgical
Intraoperative
Post operative.
Vascular - Hemorrhage
Neural
Fragmentation
Maxillary descending palatine
• Incidence : 1-1.1%
Causes:
- Supra-periosteal reflection
- Posterior wall osteotomy cut directed superiorly
- Forced downfracture and mobilization of maxilla
- Elevation of nasal mucosa from nasal floor
Intraoperative: Hemorrhage in Maxilla
Pterygomaxillary dysjunction (commonest cause)
Intraoperative: Hemorrhage in Maxilla
Management :
- Visualization of problem area
- Rapid completion of osteotomy: down fracture maxilla
- Packing and direct pressure, vascular clips, electrocautery
Turvey TA, Fonseca RJ: J Oral Surg 38:92, 1980
Intraoperative: Hemorrhage in Maxilla
Thomas Teltzrow Journal of Cranio-Maxillofacial Surgery (2005) 33, 307–313
Vessels at risk :
-Inferior alveolar A.
- Internal carotid A.
- Massetric A.
- Retromandibular
vein
- Facial vein
BSSO medial aspect : Inf alv artery lower margin: facial a. damage
IVRO sigmoid notch: Massetric artery ramus Inferior: Inf Alv artery
Intraoperative: Hemorrhage in Mandible
Intraoperative
Vascular
Neural
Unwanted fragmentation
• Neuropraxia
• Axonotemesis
• Neurotemesis
Intraoperative: Nerve injuries
Causes for Inf Alv Nerve damage: Dissection
Splitting Movements Stabilization: comp- injury
Canal - natural pathway for direct nerve regeneration.
Intraoperative: Nerve injuries - Mandible
Predisposing factors?
Low mandibular body height
Inferior position of nerve
Inferior alveolar n. injury
Prevention:Management
Tension-free suturing
of nerve
Osteotomy design
Protection
Chisel placement
Decompression of lateral fragment
Steroids
Intraoperative: Nerve injuries - Mandible
Causes:
• Retraction medially behind ramus
• Extension of distal segment beyond prox. segment
• Haematoma
• Genioplasty : direct trauma to marginal branch
• Sagittal split : direct trauma to trunk
Intraoperative: Nerve injuries –Facial N.
Lingual nerve injuries - uncommon
Causes:
• Variable course of nerve on medial aspect of mandible
• No protection to nerve while stripping on medial aspect
• Bicortical screws for BSSO : overpenetration
Intraoperative: Nerve injuries –Lingual N
• Not studied as thoroughly as mandible
• Terminal branches of infra-orbital nerve
• Clean incision Gentle dissection retraction
• Usually temporary
• Recovery 2-8 weeks.
Intraoperative: Nerve injuries –Maxilla
Intraoperative
Vascular
Neural
Unwanted fragmentation
“Deviation from osteotomy line during osteotomy procedure, resulting in osteotomy in area unrelated to surgery”
Maxilla Mandible
Intraoperative: Fragmentation
Factors:
• Bone architecture
• Bone density
• Unanticipated fractures
• Difficult fixation
• Impacted third molar
Intraoperative: Fragmentation
Sequalae :
• Infection
• Sequestration of the fragments
• Delayed bone healing
• Pseudoarthrosis
• Post operative instability & Relapse
• TMJ
Intraoperative: Fragmentation
Presurgical
Intraoperative
Post operative
POSTOPERATIVE
Loss of vascularity : aseptic necrosis
Anatomic variations: Nose, Lips
Nonunion/delayed union
Infection
Occlusal disturbances
TMJ dysfunction
Relapse
Aseptic necrosis:
• Anterior maxillary osteotomy
• Transversal maxillary segmentations
• Transection/kinking of vascular pedicle
• Major anatomical irregularities
• Poor flap design, Tearing of flaps
Postoperative: loss of vascularity - maxilla
Consequences :
-Loss of entire maxilla or segment,
-Flattening of papilla, Non vital teeth
Prevention
-Tease out descending palatine vessels during intrusion/retrusion
-Fewer Segmentation: avoid small segments
-Avoid damage to pedicle
Postoperative: loss of vascularity - maxilla
• Dr Hall HD -1978.
• 15 years - medically fit female - Le Fort I osteotomy with maxillary rib graft augmentation + BSSO + genioplasty
• 3 stage surgical plan - hyperbaric oxygen + prosthodontics involvement
• Initially 30 treatments of hyperbaric oxygen at 2.4 kPa.
• At the first operation- remaining maxillary teeth were removed + maxillary sinus and necrotic alveolar bone debrided + alveolus reconstruction with an iliac crest graft secured with miniscrews and cancellous bone,
• Interruption in Inf Alv artery:
- mandibular br of sublingual artery
- mental artery
• Complete stripping of mucoperiosteum:
- compromise periosteal blood supply
- medullary supply is already compromised
Osteotomized segment : like free autogenous graft
necrosis
Postoperative: loss of vascularity - mandible
• Risk in IVRO > BSSO
• Maintain buccal& lingual pedicles in extensive genioplasty
• Excess advancement: stretches nutrient vessel
• Ischemic tissue: intraoral free graft.
• Meticulous irrigation – supportive therapy
• HBO therapy promotes neovascularization
• Reconstruction
Management
Postoperative: loss of vascularity - mandible
POSTOPERATIVE
Alteration in Nasal form - Septum - Alar Base
Loss of vascularity : aseptic necrosis
Nose
Lip
Nonunion/delayed union
Infection
Open bite and lateral shift
TMJ dysfunction
Relapse
Nasal Septum deviation:
- Maxillary impaction : encroachment on Presurgical dimension of nasal septum
- Maxillary advancement buckling
Failure to reposition :
- Septal deviation – obstruction
- Abnormal position of columella/nasal tip
Postoperative: Nose
Intraop- Resection of inferior aspect of septum- Trim septal spurs if present- Trim bone from nasal crest of maxilla- Groove in superior aspect of maxilla
Septal deviation - How to avoid?
Management-Reoperation- Delayed septoplasty
Postoperative: Nose
Alteration in alar base and perioral structures
• Alar base widening
• Prominent alar groove
• Upturning of nasal tip – obtuse nasolabial angle
• Flattening and thinning of upper lip
• Downturning of labial commisures
Postoperative: Nose
Alar cinch suture
Pyriformplasty
Alteration in alar base and perioral structures
Postoperative: Nose
POSTOPERATIVE
Loss of vascularity : aseptic necrosis
Nose
Lip
Nonunion/delayed union
Infection
Occlusal disturbances
TMJ dysfunction
Relapse
Rare Complications
Postoperative: Lip
V-Y closure of the lip is done to prevent the shortening of the lip.
POSTOPERATIVE
Loss of vascularity : aseptic necrosis
Nose
Lip
Infection
Nonunion/delayed union
Occlusal disturbances
TMJ dysfunction
Relapse
Rare complications
PREVELANCE OF POSTOPERATIVE COMPLICATIONS AFTER ORTHOGNATHIC SURGERY: A 15-YEAR REVIEW
LOP KEUNG CHOW, BALDEV SINGH, NABIL SAMMAN. JOMS 65:984-992,2007
• N = 1294 patients ; 2910 procedures-1070 -bimax; 224-single jaw
• Total complication rate – 9.7% (out of this – 7.4% - infection)
• Higher infection rate (17.3%) in single pre-op dose of antibiotics than
patients on postop antibiotics
POSTOPERATIVE
Loss of vascularity : aseptic necrosis
Nose
Lip
Infection
Nonunion/delayed union
Occlusal disturbances
TMJ dysfunction
Relapse
Blindness
Causes
Local compromised blood supply
scarring , large advancement
large bite force - habits
postero-superior positioning
Systemic co-morbities- smoking
Prevention : principles of fixation techniques graft Bone gaps > 5mm auxillary forms of stabilization
Postoperative: Nonunion/delayed union - maxilla
Causes :
• Instability of fixation devices
• Avascular necrosis
• Large advancements with less bony contact (>7mm)
• Post op trauma
• Parafunctional habits
IVRO > BSSO
Postoperative: Nonunion/delayed union - mandible
POSTOPERATIVE
Loss of vascularity : aseptic ncecrosis
Nose
Lip
Nonunion/delayed union
Infection
Occlusal disturbances
TMJ dysfunction
Relapse
Rare Complications
POSTOPERATIVE - OCCLUSAL DISTURBANCES
- Posterior interference: maxilla when patient in IMF
- Maxilla fixed with condyles out of glenoid fossa
- Hardware Failure - screws and plates
- Fragmentation
- Edema in joints
- Condylar torque, condylar sag, incorrect placement of fragments
- BSSO- failure of rigid fixation at the osteotomy site, occlusal shifts during fixation, and finally condylar sag
Open Bites
Management :
- minor discrepancies aggressive orthodontics
- Posterior open bite < 3mm vertical elastics
- Severe discrepancies surgery
POSTOPERATIVE - OCCLUSAL DISTURBANCES
POSTOPERATIVE - OCCLUSAL DISTURBANCES
Lateral shift
Causes:
–Inadequate advancement of one side
–Equal advancement with midline shift
–Torqueing of the proximal segment
Management:
–Elastic traction
Postoperative
Loss of vascularity : aseptic ncecrosis
Nose
Lip
Nonunion/delayed union
Infection
Open bite and lateral shift
TMJ dysfunction
Relapse
Rare Complications
Intraoperative position of condyle influenced by:
• Incorrect vector during condylar positioning
• Incomplete or green-stick split prevents condylar seating
• Muscular, ligamentous or periosteal interference
• Intra-articular hemorrhage or edema
• Flexion in proximal segment while placing rigid fixation
POSTOPERATIVE – TMJ DYSFUNCTION
• TMDs 20-25% in normal population
• Karabouta & Martis – 40.8% TMDs post BSSO
• White – 49.3%
Condylar Sag
Immediate / late change in position of condyle in the glenoid fossa after surgical establishment of a preplanned occlusion and rigid fixation of the bone fragments, leading to a change in the occlusion
Reyneke ; BJOMS (2002) 40, 285–292
POSTOPERATIVE – TMJ DYSFUNCTION
Postoperative – TMJ dysfunctionCondylar sag
Central Peripheral I & II
• The condyle is seated with the condylar seating tool + light digital pressure at the angle
• resultant vector is anterosuperior
Change in shape of the condyle from normal to finger shaped with loss of height and later decrease in posterior facial height.
Van Damme JCMS 1994 ; 22, 53-58
Incidence : 2.3% and 7.7% of BSSO advancement
Postoperative – TMJ dysfunctionCondylar Resorption
POSTOPERATIVE
Loss of vascularity : aseptic ncecrosis
Nose
Lip
Nonunion/delayed union
Infection
Open bite and lateral shift
TMJ dysfunction
Relapse
Rare Complications
Stability depends on :
- Adequate presurgical orthodontics
- Long-term maxillomandibular fixation (MMF)
- Nonrigid fixation that allow muscular adaptation
- Minimal muscle alteration
- Good bony contact, and control of the proximal segment
POSTOPERATIVE - RELAPSE
Factors :
• Magnitude of mandibular advancement or setback,
• Stretch of surrounding soft tissue,
• Positioning of mandibular condyles
• Method of fixation
• Growth of mandible
• skeletal behavior among hyper/hypodivergent skeletal patterns
POSTOPERATIVE – RELAPSEMANDIBLE
• Obligate relapse after mandibular advancements >7mm
• Mandibular setback >12 mm - less skeletal relapse
• Closure of anterior open bite with only mandibular osteotomies
POSTOPERATIVE – RELAPSEMANDIBLE
How to reduce/avoid :
• Counterclockwise rotation of the mandible be avoided
• Mandibular advancement limited to < 7mm
• Bimaxillary surgery
Depends on :
• Degree of surgical advancement
• Degree of inferior repositioning of anterior maxilla
• Use of bone grafts in large advancements
POSTOPERATIVE – RELAPSEMAXILLA
Other Causes :
- Increased soft tissue stretching results in drift of the
screws during bone healing
- Reduced area of bone contact at the lateral aspects of the
maxilla - compromised union
- Preoperative scarring - Cleft maxilla
Postoperative – RelapseMaxilla
• Postoperative relapse was not considerable after total maxillary setback surgery.
• Although the amount of maxillary setback was greater, postoperative relapse did not increase significantly.
• Significant osseous regeneration at the pterygomaxillary region occurred in the early phase of recovery.
• On average, 18% of the horizontal maxillary repositioning was lost.
• Most of the change (89%) occurred during the first 6 months postoperatively.
• Relapse increased significantly with degree of surgical advancement and degree of inferior repositioning of anterior maxilla.
Remedy for prevention:
• Advance the maxilla at least 2mm more than the ideal overjet
to compensate for relapse
• Provision of a period of MMF (3—4 weeks) in addition to rigid
fixation in large advancements –
Postoperative – RelapseMaxilla - Management
Van Sickels BJOMS 1996;34:279—85.
POSTOPERATIVE
Loss of vascularity : aseptic ncecrosis
Nose
Lip
Nonunion/delayed union
Infection
Open bite and lateral shift
TMJ dysfunction
Relapse
RARE COMPLICATIONS
RARE COMPICATIONS
BLINDNESS (vasculature damage/hypoxia)
LOSS OF FUNCTION OF LACRIMINAL GLAND
CRANIAL NERVE PALSIES
DAMAGE TO INTERNAL CAROTID ARTERY
• Abnormalities of the pterygoid plates ranging from mild hypoplasia to complete absence.
• Excessive thickness of the posterior maxillary wall, which is normally hypoplastic,
Devastating complication – mechanism not clear
• Immediate swelling eyelids
• 1st post-op unable to open eye
• Manual lift –no light perception
• Intense chemosis, loss of abduction, pupillary dilatation
88
• MRI- NAD
• CT- Complex fractures of the pterygoid plates on both sides greater wing sphenoid, sinus
• Bone fragments in inferior orbital fissure
PTERYGOMAXILLARY DYSJUNCTIONschuchardt 1942
Maxillary tuberosity + Pyramidal process of palatine bone +Pterygoid plates of sphenoid
Disarticulated easily during childood (melsen & ousterhout 1987)Complexity of sutures increases with ageCause: adverse transmission of forces to skull base via sphenoid bonePrecaution during Pterygomaxillary dysjunction
RARE COMPICATIONS
BLINDNESS (vasculature damage/hypoxia)
LOSS OF FUNCTION OF LACRIMINAL GLAND
CRANIAL NERVE PALSIES
DAMAGE TO INTERNAL CAROTID ARTERY
• Color Doppler – left internal carotid flow
POST-OP 1
POST-OP 19
POST-OP 2 MONTHS
CONCLUSION
• Congenital hypoplasia internal carotid
• Statistically significant reduction in intraoperative blood loss
• Statistically significant correlation between the surgeon's perception of the quality of the surgical field and intraoperative blood pressure,
• No statistically significant decrease in operative time when hypotensive anesthesia was used.
• 3rd post-op day - CSF discharge - left nostril,
• confirmed by laboratory analysis- did not resolve
• CT cysternogram was performed.
• A lumbar drain was placed and the CSF leak resolved over several days. There were no long-term sequelae.
• Nuerological condition of unknown orgin
• Anisocoria-inequality of pupils
• Damage to innervation of ciliary muscles / ciliary ganglion
• Complete recovery in 48 hours
Facial Dysmorphophobia
• Distorted perception of one’s self appearance
• Defect may be imagined
• Minor defect excessive concern
• No other mental disorder associated
• ‘Doctor shopping’ and frequent requests for surgery
• History taking – most important
• Psychiatric counselling
Cognitive behavior therapy (CBT) - effective treatment BDD.
A meta-analysis found CBT more effective than medication after 16 weeks of treatment.
CBT may improve connections between the orbitofrontal cortex and the amygdala
CONVERSION DISORDER, 4-DAY BLUES, DEPRESSION
• Arises from the situation that has overwhelmed their usual ability to cope - hysteria
• reassure them of recovery, minimize secondary gain that may prolong recovery, honest disclosure about diagnosis, and reinforce
OTHERS
• Dysphagia- Constricted eosophageal sphincter hypoesthesia due to change in anatomy of the hyoid region- reduced tension in supra-hyoid musculature – reduced dilator effect on sphincter
• Perforation of lateral nasal mucosa by fixation screws
• OAF, Eustachian tube malfunction- damage TVP
WITCH’S CHIN
“A surgeon who has not come to cross paths with complications,
is the one who has not operated enough ”
CONCLUSION
When a true complication occurs, early recognition, rapid response and effective resolution is essential
REFERENCES
Contemporary Oral and Maxillofacial Surgery- Larry J. Peterson
Oral and Maxillofacial Surgery 2nd Edition- Raymond J. Fonseca volume 3
Essentials of Orthognathic Surgery- Johan P. Reyneke
Online resource via Science-direct & Pub-Med.