In femoral paralysis, paralysis of the quadriceps muscles, which extend the stifle, and partial paralysis of the psoas major muscle, which flexes the hip, are seen.
Femoral nerve paralysis is seen in large, newborn calves (eg, Charolais, Simmental) after the use of mechanical force during an assisted birth. Reduced quadriceps tonicity reduces tension on the patella, with the result that a lateral patellar luxation may develop. Atrophy of the quadriceps soon becomes obvious and, although the patella can be replaced easily, the animal has extreme difficulty walking. The condition may affect one or both limbs. Prognosis is related to the severity of the clinical signs.
Despite a fair or good prognosis, the animal may be unable to suckle unaided. The animal should be maintained in a well-bedded area, and colostrum given as soon as possible after birth. A radiographic study should be done to exclude fractures. The administration of anti-inflammatory drugs may be useful.