The Iliopsoas complex is made up of two back-pain-inducing hip flexor muscles - the Psoas and Iliacus. These muscles are often referred to together as a unit because they tend to function and tighten as one.
Key takeaways from Iliopsoas trigger points and tightnesses:
- Iliopsoas trigger point symptoms (more than low back pain)
- Referred pain to the low back & front of the upper thigh
- How constipation can worsen Iliopsoas induced pain
The Iliopsoas Complex 
1. If you have Iliopsoas problems, chances are you are in a world of hurt. Chances are also high you spend too much time sitting.
Iliopsoas trigger points shorten the hip flexor muscles in the front of the hip. With this issue sitting can feel comfortable, but standing up from sitting can be difficult and painful. Standing up with shortened Iliopsoas muscles (hip flexors) puts a lot of pressure on the low back, and can prevent one from standing completely upright. If you stay hunched over after standing up to prevent back and hip pain, the Iliopsoas muscles should be examined for trigger points.
2. Iliopsoas trigger points are known to refer pain to the low back and the front of the upper thigh. As shown in the left figure below, Iliopsoas trigger points can cause nasty low back pain in the lumbar spine region .
Pain is commonly felt on both sides of the low back (pictured is pain from just one side Iliopsoas comples, but both sides are generally tight together causing pain on both sides of the low back).
Iliopsoas Referred Pain Patterns . Referred pain patterns above are shown for single-sided Iliopsoas trigger points and tightness.
3. Yep, you read that right. Travell & Simons left no stone unturned in their myofascial pain analysis.
It turns out that a full bowel can place additional pressure on the Psoas portion of the Iliopsoas complex. This quote below says it all:
"Patients with constipation who also have psoas TrPs (trigger points) may experience referred pain evoked by the passage of a bolus of hard feces that presses against the TrPs. A hypertrophied psoas muscle can compress the neighboring large bowel"  p. 1202.
If you suspect Psoas trigger points contribute to your pain, make sure to pass frequent movements or your pain could worsen.
How do you release the Iliopsoas trigger points? A great way to release Psoas and Iliacus trigger points is using the QL Claw device. The QL Claw was designed to optimally massage the 5 muscles that contribute to low back pain, including the Psoas and Iliacus hip flexor muscles. Own your Iliopsoas trigger points today!
 Donnelly, Joseph M. Travell, Simons & Simons Myofascial Pain and Dysfunction: the Trigger Point Manual. 3rd ed., Wolters Kluwer Health, 2019.