Diseases of the Horse's Foot by Harry Caulton Reeks
page 33 of 513 (06%)
page 33 of 513 (06%)
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behind by the glenoid fibro-cartilage. At this point it is prolonged
upwards as a pouch behind the lower extremity of the first phalanx. THE ARTICULATION OF THE SECOND PHALANX WITH THE THIRD, THE PEDAL, OR THE COFFIN JOINT.--This also is an imperfect hinge-joint, permitting only of flexion and extension, which movements are more restricted than in the previous articulation. Three bones enter into its formation: the second phalanx, the third phalanx, and the navicular bone. The lower articulatory surface is formed by the third phalanx and the navicular bone combined. To effect this the navicular is closely and firmly attached to the third phalanx by an interosseous ligament. The two bones, as one, are then connected to the second phalanx by four lateral ligaments, an anterior and a posterior on each side. _The Interosseous Ligament_ consists of extremely short fibres running from the extensively grooved portion of the anterior surface of the navicular bone to become attached to the os pedis immediately behind its articular surface. _The Antero-lateral Ligaments_ are attached by their superior extremities to the lateral surfaces of the second phalanx, and by their inferior extremities into the depressions on either side of the pyramidal process of the os pedis. _The Postero-lateral Ligaments_.--As mentioned when describing the first interphalangeal articulation, these are in reality continuations of the lateral ligaments of that joint. Running obliquely downwards and backwards from their point of attachment to the first phalanx they curve round the lower part of the side of the second phalanx and end on the extremities and posterior surface of the navicular bone. Having reached that position, they |
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