Leg length difference

from Wikipedia, the free encyclopedia
Classification according to ICD-10
Q72.9 Leg length difference, congenital
M21.7 Leg length difference, acquired
ICD-10 online (WHO version 2019)

In medicine, the leg length difference is the possible length difference between the legs , i.e. the lower extremity from hip to foot. Minor differences do not require treatment, as most people show slight asymptomatic leg length differences. Therapy should only be considered from a difference of 6–7 mm. Leg length discrepancies in children should be monitored and treated as necessary. However, these often disappear in the course of further growth.

Basically, a distinction can be made between an anatomical and a functional leg length difference.

Anatomical difference in leg length

Real leg length difference due to side differences in length of the thigh and / or lower leg: Possible causes:

Functional difference in leg length

Without anatomical difference in length due to:


The examination with the question of a leg length difference is carried out routinely as part of the physical examination by assessing the iliac crest . Since asymmetries of the pelvic skeleton can play a role in this, a direct clinical determination of the length between the anterior inferior iliac spine via the knee joint gap to the outer ankle can also be carried out.

For the clinical definition of whether a leg length difference affects the upper or lower leg, both legs in the knee are bent by about 120 ° so that the shins are almost vertical. In the side view you can see an excess length of the thigh and in the front view an excess length of the shin. However, especially with idiopathic leg length differences, there are often differences in both the lower leg and the thigh.

Radiologically, the exact length can be determined on whole-leg still images with an integrated or attached scale.

Health consequences

Since the legs represent the basis of our statics , a large difference in leg length can cause changes in posture or in the spine , but it can also result in a secondary equinus foot. The oblique position of the pelvis leads to a more or less severe scoliosis , i.e. a sideways curvature of the spine. Although the human body has compensation options, if the leg length differences are too great, painful changes are usually the result. The compensation can be done in two ways:

  • Tip-Toeing: Walking on the tiptoe of the short leg reduces the impact. Some women even practice this gait with pumps.
  • Shoe raisers


Length differences and therapy methods:

  • <three centimeters by means of orthopedic shoe adjustments (heel raised with sole compensation and shoe insoles )
  • 3–12 centimeters using orthopedic custom-made shoes or custom-made shoes with inner shoes or foot bed orthoses
  • > 12 centimeters using floor shoes or orthopedic leg orthoses or in extreme cases and with appropriate medical indication, also surgically .

Older patients often have arthritic hip joints, so that in the course of the arthritic joint changes, the patients first show a functional leg length difference (by avoiding the pain) and after a hip replacement surgery (TEP = total endoprosthesis = femoral head replacement) often an anatomical leg length difference compensation via orthopedic shoe soles is possible.

Individual evidence

  1. HP Nowak: Compendium of X-ray adjustment technology and X-ray anatomy. Orthopedics. Traumatology. Pediatrics. 2nd Edition. ixray, 2011, ISBN 978-3-9522980-7-7 .
  2. ↑ Leg length difference. Treatment and therapy. accessed on January 29, 2014.