Hypothesis 3: Congenital Deformity

	The fact that the foal is only a few days old strongly supports the hypothesis that 
the problem is congenital.  Equine congenital deformities typically manifest within the 
first few days of life, typically presenting as lameness. The deformities can be due to 
laxity of the periarticular supporting structures. As the foal develops strength of the 
musculotendonous and ligamentous structures, the deformities resolve.  
The deformity could also be caused by incomplete ossification of the tarsal bones. 
In foals with incomplete ossification, the ossification centers of tarsal bones are smaller 
and more spherical than normal.  The stresses of normal weight bearing usually results in 
angular limb deformities. 
 Deformities can also be caused by asymmetric growth of the 
metaphysis/epiphysis.  Trauma in the form of asymmetric pathiologic compressive forces 
on the growth cartilages has been implicated as a major cause of asymmetric growth.