The Gluteus Maximus is the only muscle that exerts a posterior force on the femur, when Glute Max is inhibited the femur moves forward in the hip joint, this is known as Anterior Femoral Glide Syndrome.
With the pelvis anteriorly rotated and the femur gliding forward, the proximal femur doesn’t move during hip flexion. Instead of gliding posterior to provide room for the flexion, it glides anterior, jamming into the anterior hip capsule, and causing pain and limitation of flexion. This will cause the surrounding musculature to weaken through the process of arthrokinetic inhibition.
With inhibited Glutes the hamstrings become the dominant synergists during hip extension, the hamstrings create a bowstring effect, pushing the femoral head forward causing further pain and dysfunction. Knowing this, it makes no sense to stretch Psoas, without first addressing this syndrome, as doing so can cause more pain and irritation of the anterior hip capsule, pain will cause arthrokinetic inhibition further weakening the surrounding musculature and making low back pain worse!!
I’ve previously mentioned that if the hips lose mobility, the lumbar spine compensates for this lack of movement and this results in low back pain.
Anterior Femoral Glide Syndrome can easily be corrected with the oppropraite hip decompressiona and muscel activation protocols