Restoring Hip Flexion with Functional FAI

Restoring Hip Flexion with Functional FAI

Functional Acetabular Impingement (FAI) is something we see frequently at @bodybyboyle/@movementasmedicine.

Athletes with FAI will typically report pinching and discomfort in the anterior hip/groin during flexion (especially above 90 degrees) as well as general tightness/soreness in the groin/hip flexor region.

Before going any further it’s important to discern between Structural FAI and Functional FAI. I find the majority of athletes that we work with have a Functional FAI meaning that that their impingement is a result of tight posterior structures in the hip combined with lack of motor control over the femur and pelvis. This is something therapy and good coaching can fix. However, it is not uncommon to also find cases of structural FAI where the athletes have a congenital or acquired bony growth on the head of the femur or rim of the acetabulum that causes the impingement. While improvements in hip mobility and motor control can help improve symptoms with structural FAI the outcomes maybe mixed since the impingement is a result of structural abnormality. For this reason it is important to differentiate between the two varieties by making use of imaging and orthopedic testing.

The approach below has been very helpful for us in resolving Functional FAI issues with our athletes.


Functional FAI will almost always be the result of a loss of pelvic control. When the Ilium anteriorly rotates relative to the femur it changes the relationship of the acetabulum to the femoral head, limiting the space available for hip flexion. This is the fundamental cause of anterior hip impingement. Restoring the relative position of the pelvis l will often open up significant space for hip flexion and restore the length tension relationships in the musculature surrounding the hip.

🔹Posterior Hip Soft Tissue Work (if manual therapy is not available)🔹

If possible have a clinician with manual skills work on the athlete to improve tissue quality in the posterior hip. A good manual therapist can make a world of difference in managing FAI with your athletes so I suggest that if you do not have those skills that you find someone you can refer to. However in training or at home you can provide the athlete with some self treatment that can reduce some of the resting tone in the hip. Rolling on the posterior structures of the hip with a roller/soft ball can help create a window of opportunity of better joint position to intervene with mobility/motor control drills.

🔹Posterior Hip Active Mobility🔹

When you find impingement on the closing angle of a joint it will often be valuable to spend time mobilizing the tissues on the opposite side of that joint. In the this case a lack of tissue extensibility in the posterior structures of the hip causes the femoral head to glide superiorly/anteriorly causing impingement. I personally prefer using 90/90 PAILS/RAILS to begin restoring the tissue quality in the hip. Be sure that they do not experience an anterior pinch in their hip in the 90/90 position while practicing this drill.

🔹Hip Flexion Motor Control🔹

Once the athlete has progressed through the breathing/mobility drills and has demonstrated that they have pain free passive hip flexion I begin progressing them through active hip flexion motor control drills.

1). Prone Hip Flexion

I like to begin with this prone progression to help the athlete establish core control. It’s vital that you can teach the athlete to flex their hip without compensating through their pelvis and lumbar spine. They should be able to maintain a straight line between their head, thoracic spine and sacrum throughout the drill. Cue them to actively breathe throughout the drill, while going slow and pausing briefly at the top of the flexed position.

2). Half Kneeling End Range Lift Off with Irradiation

Once the athlete shows me they can manage hip flexion in the prone position I’ll progress them upwards to half kneeling. The half kneeling position challenges the athlete to stabilize a vertical spine in multiple planes and allows us to begin developing end range hip flexion above 90 degrees. This end range position will often be very weak on those with FAI as this is the exact range that will often be uncomfortable on intake. (Do not progress to the drill if they are experiencing pain in this position) Using dowel rods will allow the athlete create irradiation by squeezing them tightly and driving them forcefully into the ground. Be sure that the athlete keeps the torso still and only moves through the hip during the drill.

🔹Squat Progression/Goblet Squat Tension🔹

After the athlete has established hip flexion motor control I will begin reintegrating them back into the movements that originally caused them discomfort. Often that would be a Squat or Split Squat progression. I start by having them practice an assisted pattern and progress forward as they show mastery/pain free movement. I’ve outlined the squat progression on this page as well as the @certifiedFSC previously for reference. Additionally, I like to use Goblet Squat tensioning help the athlete develop strength in the end range hip flexion position. When in the bottom of the squat position I cue them to create isometric tension between their elbows and knees while focusing on breathing and bracing through their abdomen. I’ll often have them hold for 30 seconds.