Fibula Hemimelia

Fibula hemimelia is a congenital condition where part or all of the fibula bone is missing. The fibula is the smaller, outer bone of the lower leg. In this condition, the leg is also thinner and shorter. Most of the time, fibula hemimelia affects only one leg, but it may affect both sides. There are several other physical defects that may be associated with fibula hemimelia, including:

  • Partial or complete absence of the anterior cruciate ligament (ACL) in the knee
  • Congenital femoral deficiency (CFD)
  • Tarsal coalition, which means the talus and calcaneus bones are "stuck together" in an abnormal position
  • Complete or partial absence of some of the outer toes
  • Dimpling of skin and crookedness of the tibia bone


Symptoms of this condition are typically noticeable at birth, as the lower portion of the leg is visibly smaller and thinner compared to the other side. The foot may rest in an abnormal position (often pointing down and out), and some of the toes may be missing. We may use X-rays to confirm the diagnosis.


The ultimate goal of treatment, as with other congenital limb deficiencies, is to have a leg that functions well and is nearly equal in length to the opposite limb by the time your child is fully grown. Many children with fibula hemimelia are candidates for limb lengthening surgery. Prior to the first lengthening surgery, the foot is usually corrected so it sits in line with the rest of the leg. Lengthening is done with either an external fixator or with an internal lengthening device. Internal lengthening devices cannot be used until your child is a teenager. This is due to size limitations of the nail, and the fact that one of the growth plates of the leg is affected by the way the nail is inserted.

Not every child with fibula hemimelia will benefit from a limb lengthening surgery. Your child’s doctor will help guide you on which treatment method is best for your child.

Fibula hemimelia before and after

Learn more about limb lengthening