Management of congenital and acquired flexural limb deformities

摘要

In foals restriction of a joint in a flexed position or the inability to-extend a joint completely is termed a flexural limb deformity. Flexural limb deformities may be congenital or acquired. In some affected foals, in addition to the superficial and deep digital flexor musculotendon units and their accessory ligaments, the suspensory ligament, joint capsules, and collateral ligaments prevent normal extension of the joints. Malformed bones occasionally occur with congenital flexural deformities and rarely occur with acquired deformities. In utero malposition, genetic predisposition, poor nutrition, and exposure to teratogens have been suggested as causes of congenital flexural limb deformities. Acquired flexural limb deformities may be caused bynutritional imbalances, rapid growth, and trauma. Lameness in the affected limbs may precede some acquired flexural limb deformities, suggesting that pain may predispose foals to develop flexural limb deformities. Congenital flexural limb deformities most commonly involve the carpus, metacarpophalangeal, or metatarsophalangeal (fetlock)joints. Acquired flexural limb deformities usually occur in the distal interphalangeal joint of the forelimbs, or the metacarpophalangeal joints.