Leg Length Assessment

There are several ways to assess for a leg length discrepancy. Some ways are more accurate then others.

  1. The first way to assess is to have the child standing upright. You can then check the posture as well as the position of PSIS. If one side is slightly higher then the other it is possible but not definitive that the child has a leg length discrepancy.
  2. The second way to assess would be to have the child lie supine with feet stretched out in front of them. The physical therapist stands at the child's feet with one finger just distal to the medial malleolus and the other fingers stabilizing the feet bilaterally like this. The physical therapist can then ask the child to lift his buttocks in the air or bridge and check and see if that changes the alignment at all.  Bridging helps to level out the pelvis. The therapist can then help the child sit up in to long sit and again assess the position of the medial malleolus. A difference in the malleolus at any point throughout this may indicate a leg length discrepancy
  3. A third way to assess is to use a tape measure to measure from the ASIS to the medial malleolus. It is recommended to use centimeters to be more accurate. Do same measurement on the other side. A difference in the measurement from one side to the other may indicate a leg length discrepancy,
  4. A fourth way to assess leg length is to again have the child in supine and have the child bend at the knee. Make sure the feet and ankles are aligned when doing this. If one knee sit more superior then the other it is likely that the tibia of that leg is longer than the other. When viewing from the side, if one knee is more anterior then the other than it is likely that the femur of that leg is longer than the other.

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