Do you have a structural leg length discrepancy?
An actual length difference between the right and left femur or tibia.

Or a functional leg length discrepancy?
This is alot more common and caused by postural distortion.
Determining the cause of a functional leg length discrepancy is the key.
Compensation for a weakness or tightening of one area, a muscular imbalance in another location typically results.
If one hip is higher causing that leg to look shorter you have a tight QL.
The QL Is NOT a Bone…Even in THE Matt Chan
Episode 233: The Ball and Your Back + Space Mountain MWod Part 1
Thursday November 3, 2016 High Glutes & QL
Wednesday January 4, 2017 Tspine & QL