Orbital knockout fracture
Introduction
Introduction to eyelid blown fracture Eyelid smashing fractures are also called sputum bursts. The front part of the eye is hit by a blunt object, and the tissue inside the sac is squeezed toward the tip of the sacrum. The intraocular pressure rises sharply, and the pressure is transmitted to the sacral wall. The fracture of the sacral wall is weak, and the soft tissue inside the iliac crest, such as the fat around the iliac crest, and the inferior rectus muscle. And the inferior oblique muscle is in the maxillary sinus and is incarcerated. Local symptoms of swelling of the eyelids, subcutaneous hemorrhage, subconjunctival hemorrhage, subcutaneous emphysema and intraorbital emphysema. basic knowledge The proportion of illness: 0.15% Susceptible people: no specific population Mode of infection: non-infectious Complications: eyeballs
Cause
Eyelid hit fracture cause
According to Crumley (1977) 324 cases of injury, car accidents accounted for 65%, boxing 16%, blunt injuries 11%, falls 6%, other injuries 2%.
Its mechanism is as follows:
(1) The theory of sudden increase in internal pressure
The front part of the eye is hit by a blunt instrument, and the tissue inside the sac is squeezed toward the tip of the sacrum. The intraocular pressure rises sharply, and the pressure is transmitted to the sacral wall. The fracture of the sacral wall is weak, and the soft tissue such as the fat around the iliac crest and the inferior rectus muscle can be made. And the inferior oblique muscle is in the maxillary sinus and is incarcerated.
Cramer et al (1965) divided the injuries of the sacral fracture into the following five types according to the severity of the trauma:
1. Linear type without fracture piece displacement.
2. The sunroof-type displaced bone piece is often connected at the inner side, and the other end protrudes into the maxillary sinus, which is in the shape of a skylight.
3, the panel type muscle fold becomes the majority of the pieces, causing the bottom to fall like a hammock.
4. The open fracture piece falls into the maxillary sinus.
5. All the bottoms are separated.
(2) The theory of flexion of the wall
In 1974, Fujino proposed this theory through the experiment of the orbital mechanical model. It is believed that the sudden increase of internal pressure of the iliac crest can not cause the fracture of the sacral floor immediately. The external force of the iliac crest first causes the transient deformation and buckling of the entire iliac wall, and then the fracture is caused. Diagnosis and internal wall fracture support this theory, the author believes that this theory is a continuation of the theory of internal pressure surge, which can be combined.
The fundus is inclined downward from the inside to the outside, so the lowest part of the bottom of the sac is located in the 3mm dent of the front outer part, which is the shortest in the anteroposterior diameter of each wall, with an average of 47mm. The bottom of the sac is mostly composed of the maxillary ridge and the iliac crest. The composition of the epiphyseal surface is about half of the inside and outside of the sacral floor. In addition, there is a small part of the humeral condyle.
Between the maxillary fascia and the humeral humerus is the inferior sulcus, which is connected backwards and inferior iliac crest, and forms the infraorbital tube forward. The outer hole is located about 4 mm below the inferior temporal margin, with the infraorbital nerve and The inferior phrenic artery passes through, so the buccal numbness often occurs in the sacral fracture. The iliac crest is the thinnest at the inner side of the infraorbital fissure 1 to 3 mm, which is a common point of fracture.
The rectus muscle is close to the sacral floor, but to the front of the sacral floor is separated by the oblique muscle of the lower eye and the fat of the iliac crest. The nerve supplying the lower rectus muscle enters the upper part of the 1/3 junction of the muscle, so in most of the iliac crest. In the case of a base fracture, the inferior rectus muscle is not easily damaged, but only the inferior oblique and inferior rectus muscles are involved.
The sieline paper sample on the inner wall of the iliac crest is the thinnest, 0.2 to 0.4 mm, so the fracture of the sacral floor is often accompanied by a fracture of the medial wall of the iliac crest.
Prevention
Eyelid blown fracture prevention
Strengthen publicity and education, and regularly publicize and educate in the factory to make workers understand the harm of eye injuries and the significance of preventing eye injuries, and understand common sense of prevention. Publicity and education should also be carried out when harvesting, applying pesticides and infrastructure in rural areas. Strict implementation of the security system. First develop safety systems and operating procedures, regularly check implementation and check equipment.
Complication
Eyelid rupture complications Complications
Eyeballs are trapped, eye movement is limited, numbness of the infraorbital nerve distribution area, visual impairment, and the like.
Symptom
Eyelids, blown fractures, common symptoms, visual acuity, eyelid edema, eyeball, inability to move, double vision, comminuted fracture, optic atrophy, bloody eyeball
Clinical manifestations:
1, local symptoms of eyelid swelling, subcutaneous blood stasis, subconjunctival hemorrhage, subcutaneous emphysema and intraorbital emphysema.
2, the complex as the lower rectus muscle incarcerated in the fracture gap, the two eyes appear this phenomenon, often appear after the acute reaction subsided, the downward shift of the eyeball is also one of the causes of diplopia.
3, the eyeball moves down into the soft tissue of the sacral fall into the maxillary sinus, with a line straight horizontally in front of the eye, it can be seen that the injured side of the pupil is lower than the healthy side.
4, the eyeball is trapped early due to edema in the sputum, hemorrhage, only the eyeball is prominent, the eye drops after a few days after the injury, mainly due to the enlargement of the sacral cavity and the fat in the iliac crest into the maxillary sinus. Late lesions such as fat-induced necrosis, post-ball adhesion, and shortening of extraocular muscle scars also have important relationships.
5, eye movement limitation is often limited by the movement of the vertical axis of the eye, the mechanism is still inconclusive, the theory of internal pressure surge is considered to be caused by the inferior rectus muscle in the fracture site, Koonreef (1982) according to anatomical studies, Eye movement disorder is caused by bleeding and swelling of connective tissue around the extraocular muscles, resulting in neurological dysfunction. Hammerschlag (1982) found through CT scan that the movement of the inferior rectus muscle is caused by the dislocation of the contents and the distraction of the muscle. cause.
6. The numbness of the infraorbital nerve distribution area is caused by the infraorbital nerve injury. The numbness is the lower jaw, the cheek, the wing and the upper lip. This disease also occurs in the inferior temporal margin fracture, which is not unique to the sacral fracture. Half of the patients' numbness can resolve within a year.
Examine
Eyelid rupture
1. Check the upward movement of the eyeball. If the affected eyeball cannot rotate upwards, the diagnosis can be confirmed.
2, palpation of the margin, with or without step deformation and displacement.
3, numbness of the infraorbital nerve distribution area, has reference value.
4, inferior rectus traction test conjunctival sac inner surface anesthesia, with ophthalmic toothed forceps from the sclera to the lower rectus muscle tendon, so that the eyeball rotation, if it has been incarcerated, the eye movement is limited, can be compared with the healthy side.
The lower rectus aponeurosis was clamped with forceps, and it was confirmed that the eyeball supination motion was restored.
5, X-ray film has important diagnostic value, the nose position, nasal position and lateral position, the following lesions can be found: 1 abnormal soft tissue shadow on the top of the maxillary sinus, 2 visible sacral tissue into the top of the maxillary sinus, In the case of hanging hammock-like shadows, 3 sometimes visible blood and sacral bone fragments protrude into the maxillary sinus, 4 bones of bone defects.
6. The CT scan of the ankle and the CT scan of the coronal plane can clearly show the fracture state and the extent of the sputum content, and can also display other facial fractures, which can comprehensively evaluate the patient's injury.
Diagnosis
Diagnosis and diagnosis of eyelid blown fracture
Differential diagnosis
1. Bottom fracture: 1 simple humeral fracture, no injury to the gingival margin, 2 complicated sacral fractures, sacral margin and facial fracture.
2. Orbital pleomorphic fractures: 1 linear fracture involving maxillary and humerus, 2 sacral fractures with mid-face fracture, 3 humeral fractures, frontal crease separation, downward displacement of the humerus .
