Hip Hook vs. Core Nexus: Which Tool Actually Releases Both Hip Flexors?

The Hip Hook reaches the iliacus but not the psoas. Core Nexus is the only tool that addresses both muscles with dedicated tip geometry.

If you're researching psoas and iliacus release tools, two names come up constantly: the Hip Hook by Aletha Health and the Core Nexus by Nexus Health Tools.

Both address the same thing — tight hip flexors that drive lower-back tightness, hip stiffness, and the pelvis getting pulled forward. Both are legitimate tools designed by people who understand the anatomy.

But there's a fundamental structural difference between them that most comparisons don't address: the Hip Hook can only effectively release the iliacus. It wasn't designed to reach the psoas — and here's why that matters.

Two Muscles, Two Problems, Two Different Shapes

The psoas and iliacus are two distinct muscles in two different locations. They work together as the iliopsoas complex, but releasing them requires completely different pressure:

This is why a single-tip design faces a fundamental tradeoff. A tip narrow enough to fit inside the hip bone and reach the iliacus is too small to effectively access the psoas deep in the abdomen. The pressure concentrates into too small an area and can't penetrate broadly enough through the abdominal wall to reach the psoas against the spine.

The psoas runs along the lumbar spine (T12–L5). The iliacus lines the inside of the hip bone. Each requires a different tip shape to reach effectively.

Hip Hook: Effective for the Iliacus, Not the Psoas

The Hip Hook was designed by Christine Koth, a physical therapist. It has a single narrow tip designed to reach the iliacus inside the hip bone — and it does this well. The narrow, angled design follows the curve of the pelvic wall and applies targeted pressure where the iliacus lives.

But that same narrow tip is structurally unable to provide the broad, deep pressure the psoas requires. The psoas sits behind layers of abdominal muscle, fascia, and organs. Reaching it requires a wider contact surface that distributes pressure across the abdomen to press through to the depth of the lumbar spine. A narrow tip simply doesn't cover enough area — the pressure is too concentrated to penetrate effectively, and it's uncomfortable without being therapeutic.

Bottom line: The Hip Hook is an iliacus tool. If the iliacus is the primary issue, it works. But if the psoas is also locked up — which it almost always is for people with long-term sitting-related lower-back tightness — it addresses only half the problem.

Core Nexus: Two Muscles, Two Tips

Core Nexus was designed with this exact limitation in mind. It has two distinct, muscle-specific tips:

• Wider tip — shaped and angled for the psoas. The broader contact surface distributes pressure across the abdomen, allowing it to penetrate through to the depth of the lumbar spine where the psoas lives. This mimics how a physical therapist uses a broad palm and forearm to access the psoas manually.
• Contoured tip — shaped to follow the curve of the hip bone and reach the iliacus inside the pelvic wall. Narrower and angled differently than the psoas tip, because it's accessing a different muscle in a different location.

Core Nexus features two distinct tips — a broader surface for the psoas and a contoured tip for the iliacus — both rotating independently on the base.

Both tips rotate independently on the base, adjusting to the body's unique anatomy as you breathe and shift during a release. This is a meaningful difference from static tools — instead of repositioning the entire body to change the pressure angle, the tips follow the user. When the leg rotates outward to deepen the release (the same technique a PT uses), the tips rotate with the movement and maintain contact at the optimal angle.

The tool works with the body instead of making the body work around the tool.

Why Releasing Both Matters

This isn't a theoretical distinction. It's the mechanical reason people get temporary relief that doesn't last.

The psoas attaches to the spine. The iliacus attaches to the pelvis. When both are tight, they create a dual pull — the psoas yanks the lumbar vertebrae forward while the iliacus tilts the pelvis. This combination produces the classic tightness pattern: a loaded lower back, anterior pelvic tilt, under-active glutes, deep hip tightness, and stiffness after sitting.

• A tight psoas pulls the lumbar spine forward into excessive lordosis
• A tight iliacus tilts the pelvis forward (anterior pelvic tilt)
• Together, they create a dual pull that loads the lower back, leaves the glutes under-active, and drives the cascading tightness pattern most people feel

Release both, and the system has a better chance to reset. The spine can return toward neutral. The pelvis can level. The glutes can re-engage. That's when people often feel the difference.

The Two-Tool Problem

Here's the reality that no single-muscle tool company will mention:

If you own a Hip Hook (iliacus only), you also need something like a Pso-Rite (psoas only) to address the complete problem. And if you own a Pso-Rite, you also need something for the iliacus.

A Hip Hook for the iliacus plus a separate psoas tool means two purchases, two learning curves, and twice the time per session — to cover what one properly designed tool handles on its own.

Core Nexus replaces both. One tool. Both muscles. The correct geometry for each.

Head-to-Head Comparison

Who Each Tool Is Best For

Hip Hook May Be Right If:

• The primary issue is iliacus tightness specifically
• A separate tool or method for psoas release is already available
• A physical therapist supplements the psoas release manually

Core Nexus Is Built For:

• Anyone who needs both the psoas AND iliacus worked on (most people with recurring lower-back or hip tightness)
• People doing self-release at home without regular PT access
• Those who've tried single-muscle tools and still aren't getting complete front-of-hip release
• Anyone who wants one tool that handles both muscles with the correct geometry for each

The Bottom Line

The Hip Hook isn't a bad tool — it does what it was designed to do, and it does it well. The question is whether what it does is enough.

For most people dealing with recurring lower-back and hip tightness from prolonged sitting, the answer is no. The psoas and iliacus tighten together, compensate for each other, and respond best when worked together. A tool that can only effectively reach one of the two is solving half the problem.

Ready to work on both muscles — not just one?

Core Nexus comes with a 30-day money-back guarantee and a lifetime warranty.

Find Core Nexus on Shop Direct at

Endorsed by Leading Clinicians

Dr. Michelle Goñi MD

Dr. David Sosa DC

Dr. Dan Lang PT, DPT

Dr. Jon McHale DC

Dr. Steph Dorworth PT, DPT — Physical Therapy

Nexus Health Tools Anatomy-Based Mobility Tools

Nexus Health Tools designs precision instruments for targeted myofascial release, built on real anatomy and endorsed by clinicians. Every product is engineered in the USA to address the muscles most tools miss.