A practical treatise on fractures and dislocations . , it is probable that in most persons it advances rather in frontof the centre of the eminence; so that in order to become actuallydislocated it only needs that the capsule shall be somewhat relaxed, orthat it shall actually give way in front, when the condyles slide for- 1 Gilbert, Thesis on Dislocation of the Inf. Max. University of Buffalo, 1858. DOUBLE OR BILATERAL DISLOCATION. 535 wards and occupy a position directly in front instead of behind thiseminence. It is easy to comprehend how the combined action of the two externalpte
A practical treatise on fractures and dislocations . , it is probable that in most persons it advances rather in frontof the centre of the eminence; so that in order to become actuallydislocated it only needs that the capsule shall be somewhat relaxed, orthat it shall actually give way in front, when the condyles slide for- 1 Gilbert, Thesis on Dislocation of the Inf. Max. University of Buffalo, 1858. DOUBLE OR BILATERAL DISLOCATION. 535 wards and occupy a position directly in front instead of behind thiseminence. It is easy to comprehend how the combined action of the two externalpterygoid muscles, with a portion of the fibres of the masseter, mayalone produce the dislocation when the mouth is wide open, and espe-cially when, in consequence of a slight blow upon the chin, the anteriorportion of the capsule becomeslacerated; for it must be noticedthat the ascending ramus, withits prolonged condyloid process,constitutes a lever of the firstkind, in which the temporalmuscle, attached to the coronoidprocess, the masseter, and even. Double dislocation of the inferior maxilla. the mastoid process, constitutethe fulcrum, the anterior portionof the capsule, the weight, andthe force acting against the frontof the chin, the power. In this position of the condyle,drawn upwards and forwards bythe action of the pterygoid andtemporal muscles, the chin descends toward the neck, and the coronoidprocess rests against the back of the superior maxilla, or against themalar bone at the point of its junction with the upper maxillary. Thetemporal, masseter, and internal pterygoid muscles are very much uponthe stretch, if not more or less lacerated. Symptoms.—The mouth is widely open and the jaw nearly immov-able. It has been noticed generally that, by pressure, the chin maybe slightly depressed, but that, owing probably to the pressure of thecoronoid process against the body of the upper maxilla, or against themalar bone, it is generally impossible to elevate the jaw in any de
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectfractur, bookyear1875
