condylar injury

Mental foramen for V3 sensory branch Coronoid process of mandible Mandibular notch neck condyle Mandibular fossa Articular emminence

Categories of condylar injuries: 1- Contusion: Injuries to the soft tissues around the joint or an effusion within the joint. 2- Dislocation: Mean displacement of the condylar head from glenoid fossa but still within the capsule. 3- Fracture: Intracapsular( head or neck) and extra capsular (neck or subcondylar)

Classification of condylar fracture 1-unilateral or bilateral fracture. 2- intra capsular or extra capsular. 3- Lindahls classification: 1- Level of condylar fracture into : a- Condylar head fracture ( intra capsular) . They are further classified into vertical fracture, compression fracture, and comminuted fracture. b- Condylar neck fracture : Which is the thin constricted area located immediately below the condylar head .

c- Sub condylar fracture : the region below the neck . 2- relationship of the condylar segment to the mandible into : a- un displaced ( hair line fracture). b- deviated . c- displaced with medial or lateral overlap. d- displaced with anterior or posterior overlap. e- no contact between the fracture segments.

Signs and symptoms of condylar fracture. 1 -Signs of trauma like wounds over the chin or ecchymosis or hematoma over the TMJ. 2- Swelling over the TMJ due to hematoma, edema, or dislocated condyle which is visible and palpable. 3- Bleeding from the external auditory canal (superior dislocation).

4- Battles sign which is ecchymosis of the skin below the mastoid process . This also occur with fracture of the base of the skull.

5- Deviation of the mandible towards the fractured side on opening the mouth. 6 - When there is medial dislocation of the joint, there will be a characteristic hollow is seen in the preauricular region.

7- Gagging of the occlusion( posterior pre mature contact) in the ipsilateral side with ipsilateral midline shift. 8- Pain and tenderness over the TMJ region . 9- Pain during lateral excursion to the opposite side and during protrusion. 10- Facial asymmetry. 11- Crepitation over the TMJ. 12- In bilateral fracture there is anterior open bite.

Investigations: OPG transcranial view of the TMJ revers Townes view. CT scan. MRI.

Treatment of condylar fracture It may be conservative or surgical : 1- Conservative treatment : It may simple observation and soft diet or may include IMF for a short period of time. 2- Surgical treatment or open reduction: the joint space is surgically exposed and the condyle fixed in its original position by wire or plate.

Conservative 1- Minimal displacement: No active treatment . A normal occlusion is maintained which allows bony union to occur. In fracture-dislocation a functional psuedoarthrosis may be produced. 2- Persistent malocclusion or severe pain indicated for a short period of IMF(7-10 days).until edema and muscle spasm disappear. 3- Bilateral fracture: a longer period of IMF (3-4) weeks with posterior distraction block. Elastic traction may be necessary to close anterior open bite.

Indications for open reduction of condylar fracture Absolute indication 1-Fracture dislocation of the condyle to the middle cranial fossa. 2- Lateral fracture dislocation of the condyle. 3- Impossibility to achieve adequate occlusion by closed reduction . 4- Invasion by foreign bodies.(compound fracture as in gun shoot)

Relative indications: 1- Patient in whom IMF is not recommended like mentally retarded patient , epileptic patient, or those having severe respiratory disorders. 2- Bilateral fracture condyle with comminuted midface fracture. 3- Bilateral fracture condyle of edentulous patient with atrophic ridges in whom splinting is not recommended.

Surgical approach to the TMJ 1- Pre auricular approach. 2- Sub mandibular approach . 3- Intra oral approach. 4- Bicoronal flap in bilateral condylar fracture. Methods of surgical treatment include; 1- bone plating 2- transosseous wiring 3-K wire 4- external pin fixation.

Complications of condylar injuries 1- TMJ pain /dysfunction syndrome. 2- Disturbance of mandibular growth. 3- TMJ ankylosis.

Condylar fractures Intraoral approach Ramus incision Extraoral approach Preauricular approach Retromandibular approach