Femoral Anteversion

The femurs are directed at an inward rotation during weightbearing activity due to soft tissue contractures or boney abnormality at the level of the hip (left). In manu cases the knee is pointed inward with the femoral guidance but the tibia is directed outward to compensate (right image). This is called knee mal-alignment syndrome and cause structural damage with wear and tear to the knees especially with attempt at increased or hight intensity activities.

FEMORAL ANTEVERSION
By:  Robert H. Sheinberg, D.P.M., D.A.B.F.A.S., F.A.C.F.A.S. 

Femoral anteversion is the most common cause of an intoe gait in children greater than 3.  It is caused by a twisting of the thigh bone.  The thigh bone (femur) has an internal twist when comparing the lower to the upper portion of the bone.  This twist is greatest at birth.  There is a gentle steady untwisting of the bone that takes place until about age 12.  From the ages of 12-16 the change is more subtle as it reaches an adult value. 

CAUSE:

  • An excess is a developmental abnormality.
  • Due to intrauterine position.
  • Genetic predisposition.
  • Tight hip muscles and hip ligaments contribute to the problem.

CLINICAL EXAMINATION:

  • Determining femoral anteversion is usually based on a thorough clinical examination.  An examination of the hip range of motion usually reveals that there is a greater internal than external rotation when measuring motion with the hip extended.
  • In rare cases x-rays and CT scans may be needed, especially if there is asymmetry of motion between the right and left hip.  This may indicate hip dysplasia. 

SIGNS AND SYMPTOMS:

  • Intoe gait, more noticeable when a child begins school.
  • When standing in the patient’s normal posture, the patella (kneecaps) appear to point in or squint towards each other.
  • While observing the patient walk, the knee and patella (kneecap) appear to be turned in.  May worsen at the end of the day when the child fatigues. 
  • Child usually likes to sit in a “w” position (pictured below)
  • Running appears to be awkward.
  • If associated with internal tibial torsion (internal position of the lower leg bone on the upper leg bone) a child may trip and fall when running.
  • If associated with external tibial torsion (lower leg bone excessive rotated outwardly compared to the upper leg bone) may cause significant malalignment syndrome of the knee.
  • More common in girls.
  • Usually symmetrical between the right and left sides.

 photo FemoralAnteversion_AnJs.jpg

TREATMENT:

The angle of the lower to the upper leg bone steadily diminishes until age 12.  The condition usually resolves by that time. 

  • Observation of the change in position of a child’s knee and foot progression may be all that may be necessary.
  • Exercises to stimulate flexibility of the hip towards external rotation.
  • Activities, especially ballet for girls and rollerblading for boys and girls may help to improve hip flexibility towards external rotation.
  • If asymptomatic no treatment is needed.
  • If a condition is excessive (inner rotation greater than 80 degrees and lateral rotation less than 10 degrees) and there is associated tripping or severe cosmetic concern, surgery could be considered after the age of 10.  The delay is necessary because of the possible spontaneous resolution of the problem up until the age of 16. 
  • If associated with external tibial torsion (excessive motion of the lower leg on the upper leg to the outside) and significant knee problems develop, surgery may also be needed to realign the extremity. 

PROGNOSIS:

There is a natural decrease in the intoe gait associated with femoral anteversion that occurs in 99% of the cases.  The patient should be followed and reassurance should be given to the parents that these cases will almost always resolve in time.  It is important to ascertain whether or not the child has internal tibial torsion or external tibial torsion associated with femoral anteversion.  This may change the prognosis.  Femoral anteversion by itself typically does not lead to arthritic changes in the hips or knees and should not be treated surgically unless significant symptoms warrant it. 

Femoral anteversion, with the knee peaking in, which can cause intoe gait