There are several types of leg length discrepancy.
1.Structural Leg Length Discrepancy
As the name suggests, it means there is a genuine difference in the length of the two legs. This condition may result from congenital defects caused by incomplete development of the leg bones or inherent diseases. It can also be brought on by trauma or infection. For children in the growth period, trauma or infection in the lower limbs may disrupt the bone growth plates, leading to overgrowth or stunted growth of bones, and ultimately unequal leg lengths
2.Functional Leg Length Discrepancy
It refers to a condition where the bones of both lower limbs are actually equal in length, yet one leg appears shorter due to uneven length of joints, muscles and other soft tissues in the lower extremities. This type is caused by altered bodily biomechanical alignment. Such biomechanical changes lead to abnormal posture and apparent leg length difference. It further triggers compensatory reactions in other joints and body parts, resulting in functional leg length discrepancy indirectly.
How to Check for Leg Length Discrepancy by Yourself
1.Asymmetrical weight-bearing sensation on both sides during squatting, walking, running and jumping.
2.You tend to lean to one side when squatting, marching in place with eyes closed, or walking forward with eyes closed.
3.Lie flat on your back, grip your ankles and pull gently towards your feet; the soles of your feet fail to align.
4.Lie on your back with knees bent at 90 degrees; the two knees are at different heights.
5.Asymmetrical gluteal creases and uneven pelvic height on both sides.
What are the harms of leg length discrepancy?
1.Leg length discrepancy may lead to scoliosis. Pelvic tilt causes the lumbar spine to deviate to one side, which gradually results in scoliosis.
2.Uneven shoulder height. In patients with leg length discrepancy, the pelvis rises and the shoulder drops on the longer leg side, while the pelvis lowers and the shoulder lifts on the shorter leg side.
3.Abnormal or asymmetrical foot development. For those with structural leg length discrepancy, the hindfoot on the longer leg tends to pronate and is prone to flat feet; the hindfoot on the shorter leg tends to supinate and is likely to develop a high-arched foot.
4.Pelvic tilt and leg length discrepancy cause asymmetry in the musculoskeletal system, most notably pelvic tilt.
5.Musculoskeletal pain
Leg length difference disrupts the bilateral biomechanical balance of the body. Excessive load is placed on certain body structures, leading to persistent pain that is hard to relieve.
Surgery is generally not recommended for structural leg length discrepancy.
1.Difference less than 2 cm: Custom 3D-printed orthotic insoles are commonly used for correction.
2.Difference over 2 cm: Height-adjusted 3D-printed orthotic insoles are applied for adjustment and correction.
In short, leg length discrepancy in children is a problem that cannot be ignored. Parents should keep a close eye on their children's growth and development, detect issues early and take timely measures.
With scientific prevention and treatment, we can help children maintain healthy legs and grow up happily.
