I've had a lateral pelvic tilt to my right side for quite some time, and no matter how much I try to strengthen my left leg to correct it, it never seems to get any better. I was hoping you could suggest some exercises that might help me fix it.
Based on your description of lateral pelvic tilt to the right and wanting to strengthen your left leg, I’m assuming that the left side of your pelvis is high and the right side is low. I like to refer to this as a frontal plane deviation, in that your pelvic positioning has moved outside of efficient biomechanical alignment within the frontal plane.
Although muscle weakness is a potential cause of a lateral pelvic tilt, there are also several other causes. The first thing to rule out is a “true” leg length discrepancy. The term “true” is applied because it describes an actual length difference in the bones on the right and left sides. This can occur in either the femur or the tibia or both. A short leg will cause a pelvic unleveling/lateral pelvic tilt.
Another cause of a leg length discrepancies not created by boney differences is unilateral overpronation at one subtalar joint. The flattening of the arch on this foot will bring the ipsilateral (same) side of the pelvis closer to the floor, causing this leg to appear shorter, thereby causing the pelvis to tilt laterally.
Another possible cause is flexion in the knee on the same side of the “short leg.” This does not have to be an excessive amount of flexion. Any degree of difference from the other knee will cause the leg with greater flexion to be shorter. This can even occur if the flexion in the knee of the shorter leg is normal, but the knee of the longer leg is in recurvatum.
If there is not a leg length difference, than another possible cause is weakness in the hip abductors on the high side of the pelvis. With the feet fixed to the ground, if the axis of the left hip joint shifts to the left because of poor support of the frontal plane stabilizers, the left side of the pelvis will rise and the right side will drop. There will often be an associated tightness in the left hip adductors that are part of this frontal plane deviation.
General strengthening of your left side might actually be compounding your problem. For example, if you do closed chain, unilateral exercises on your left side without addressing the underlying cause of the tilt, your body will continue to use its existing strategy for stabilization that it has developed with a lateral pelvic tilt.
It would make sense to initially correct the lateral pelvic tilt if it is not due to a leg length discrepancy. And even if it were due to a leg length discrepancy, you would want to reduce the secondary compensations created by the leg length discrepancy. It is not uncommon for someone with a 1/8 of an inch leg length discrepancy to have a much greater difference in that lateral pelvic tilt because of the compensations over time.
I am a strong advocate of using corrective exercises to establish new motor learning and biomechanical strategies prior to tri planar, multi joint exercises in cases such as yours. You may want to look at my DVD, Corrective Exercises for Powerful Change, that provides specific exercises for frontal plane deviations.
Best of Luck