In Part 1 I introduced some of the issues that come into play when someone has a leg length difference. Here is my evaluation protocol when I assess postural asymmetry.
Health History
Some people are aware they have postural asymmetry. I’ve worked with father/son and mother/daugthters where the child has the same postural alignment as the parent. I’ve also been in social settings having observed four generations of the same family, from great grandchild child to great grandmother – they all have the same postural asymmetry. People treated by chiropractors will report having their pelvis adjusted to make their legs the same length. SI joint, spine and sacrum manipulation can “correct” pelvis and leg asymmetry if there is joint hyper mobility/fixation and muscle spasms. Manipulation cannot “fix” anatomical variations. Some folks need to have pants hemmed at different lengths. Often they are aware of one foot being smaller/larger.
Postural Analysis
I observing how someone stands, sits, walks and moves. Asymmetry in alignment or muscle tone is a red flag that needs closer evaluation. I can learn a lot about the health of the hips and legs from observing the feet. While they are standing I palpate body landmarks such as the top of the pelvis and scapulae checking alignment, I chart findings.
Gait & Movement Assessment
Balance tests, squats, lunges and jumping demonstrates how well someone organizes their body during dynamic movement while under load. Gait analysis is a whole body movement screen that also provides info about specific joint control. I take video/movies in my office or clients send me video of them running/biking. Video analysis is a great tool.
Range of Motion and Manual Strength Testing
Checking range of motion assesses soft tissue quality, muscle tone and joint integrity. For instance if one hip has significant more/less mobility or strength it will show up in posture and movement.
Orthopedic tests
Back muscle spasms and SIJ dysfunction can disrupt the alignment of the pelvis and create the appearance of leg length difference. The Long Sit Test is probably the most useful test to assess if there is a bony discrepancy or muscular tightness. While lying down I check the position of the ankles/heel, then the client sits up, I recheck alignment then have them lie down again. If the ankles are not even throughout this movement sequence there is good probability the asymmetry is skeletal and not muscular. If the leg length flip flops during this sequence then I am more concerned about SIJ ligament injury. If a SIJ mobilization realigns the feet, this then confirms possible SIJ dysfunction (more on SIJ injuries in another post).
Shims
I position the client in front of a large mirror in my office, we both observe their alignment. I then place plywood shims of various thickness (1/8″, 1/4″, 1/2″) under the shorter leg foot. Adjusting the shims allows me to roughly dial in the approximate length difference. I let them stand w/the shim for a few minutes then remove it. Often people experience a sense of equilibrium, they also notice how much their body tilts to the shorter leg side. Placing the shim under the longer leg feels really awkward typically.
What next?
As mentioned in my previous post my assessment process is not a diagnosis. If I suspect a leg length I discuss options with the client. A true diagnosis comes via an orthopedic eval and x-ray, since most folks are not in chronic pain or need surgery an x-ray is usually not needed. One option is to consult with a podiatrist. A custom orthotic can be made to shim the foot, if the discrepancy is more that 3/16″ shoes may need to be modified, it all depends on how big a difference is and how the body has adapted to the asymmetry. Competitive cyclists usually need some modifications made to their shoes or cleats otherwise their pedal stroke, power output R/L and their comfort (they tend to shift side/side) is compromised.
For most clients w/minimal leg differences knowing they are not symmetrical helps them to modify their movement strategies. If they keep their legs and hips strong people tend to do really well w/out orthotics. The tricky part of this is what happens to a person over their life span. I’ve had a few older clients that have arthritic knees, had knee replacements and have scoliosis/arthritic spines. Perhaps if they had known about the leg length difference as a younger person and had an exercise routine that supported better postural alignment would they have had these conditions later in life?
