The bones measure differently
The femur, tibia, or both are truly shorter or longer. Causes can include congenital development, growth disturbance, fracture, infection, bone loss, or prior surgery.
Assessment pathway
A measured difference is not the whole diagnosis
The useful sequence is to define the type of difference, measure it in a reproducible way, identify its cause and alignment effects, and only then discuss treatment.
The legs may measure similarly
Pelvic position, spinal curvature, hip or knee contracture, foot and ankle position, or another movement problem can create an apparent difference.
History and symptoms
Onset, prior injury or surgery, pain, fatigue, gait change, footwear and functional goals.
Standing and gait exam
Pelvis, spine, joints, foot position, range of motion and compensation are examined together.
Block test
Measured blocks under the shorter side estimate the correction that levels the pelvis while standing.
Targeted imaging
A calibrated full-length standing radiograph can measure anatomic length and weight-bearing alignment.
Shared decision
Symptoms, cause, alignment, health, goals and treatment burden matter alongside the number.
Educational reference only. Not medical advice. Home measurements cannot distinguish structural from functional causes or select treatment.