ACL Injuries: Why the Real Cause May Be Elsewhere (Patrick Mahomes Analysis)
Key insights: 60-second read
- ACL injuries aren't always "bad luck" – many non-contact tears expose hidden mechanical flaws that were already present.
- The ankle is often the overlooked culprit – residual stiffness from past ankle sprains can create a functional "handbrake" that forces the knee to compensate.
- Lower back and hip function matter too – poor core control or weak glutes can cause the knee to cave inward (valgus), a classic ACL strain position.
- Patrick Mahomes' injury history offers clues – public records show multiple foot/ankle issues before his ACL injury, highlighting the potential chain reaction.
- Rehab is an opportunity to optimise the whole leg – ACL recovery is a chance to address hidden dysfunctions and build a more resilient athlete.
When a high-profile athlete like NFL star Patrick Mahomes suffers an ACL tear, it's often put down to the brutal, unpredictable nature of contact sports. But what if these injuries could sometimes be a consequence of hidden, pre-existing limitations elsewhere in the body? As a Physiotherapist, looking beyond the knee itself can reveal crucial factors that might influence injury risk and recovery.
In my recent video, I explore the idea that an ACL injury might not always be a simple knee failure, but potentially a result of subtle dysfunctions in the lower back, hips, or ankles. Using available footage of Patrick Mahomes, I discuss themes I frequently see in clinical practice.
On this page
Shifting Our Perspective on ACL Tears
It's common to view an ACL rupture as a moment of pure bad luck - being in the wrong place at the wrong time. While direct trauma happens, many injuries occur during non-contact movements like landing or cutting. This suggests the moment of injury might expose underlying mechanical flaws that were already present.
A Key Clinical Concept
The instant an ACL tears may be the moment that reveals the quality of pre-existing leg mechanics. The ligament might simply be the structure that couldn't tolerate forces generated by hidden restrictions or weaknesses further up or down the kinetic chain.
This perspective is vital for rehabilitation. The goal isn't just to rebuild the knee, but also to address any hidden dysfunctions that may have contributed to the vulnerability in the first place.
Common Hidden Factors to Consider
When assessing someone for ACL injury risk or during their rehab, I often look at a checklist of areas that could be influencing knee load.
The Potential Contributors
- Lower Back Function: Stiffness, poor core control, or slouched sitting postures can affect the nerve signals controlling leg muscles, potentially altering how the knee is stabilised.
- Hip Mobility & Strength: A lack of hip rotation or weak gluteal muscles can cause the knee to cave inwards (valgus), a position frequently linked to ACL strain.
- Ankle Mobility: This is often the most overlooked factor. Restrictions in ankle dorsiflexion (bringing your toes toward your shin) can force the knee to compensate and move differently during activity.
Why Ankle Mobility Deserves More Attention
In reviewing Patrick Mahomes' case, his past injury history stood out. Public records indicate several foot and ankle issues over recent years. Clinically, a common long-term effect of ankle sprains is a residual loss of ankle dorsiflexion range.
Many people finish rehab once pain and strength return, but never fully restore their end-range ankle mobility. Over time, this creates a functional "handbrake." During dynamic sport, if the ankle can't move freely, the body may find a path of least resistance, potentially putting excessive strain on the knee.
Furthermore, footwear choices may play a role. Consistently wearing shoes with an elevated heel can subtly reduce the time your ankle spends in a stretched, dorsiflexed position, which might contribute to stiffness over time.
Clinical insight: After any ankle sprain, restoring full range of motion should be a key goal - not just reducing pain and swelling. That residual stiffness can travel up the chain and become someone else's problem (often the knee).
Practical Takeaways for Prevention & Recovery
Whether you're an athlete or someone wanting to stay active, this perspective encourages a more holistic approach.
- Think Beyond the Knee: If you've had an ACL injury or want to prevent one, consider asking your physio or trainer to assess your lower back, hip, and ankle function.
- Prioritise Full Ankle Rehab: After any ankle sprain, make restoring full range of motion a key goal, not just reducing pain and swelling.
- Consider Your Footwear: Incorporating time in minimal or flat shoes (gradually) can encourage natural ankle mobility and leg strength.
- Rehab is an Opportunity: ACL recovery is a long process. It can be a valuable time to not only heal the knee but to optimise the entire leg's mechanics for a stronger return.
While not every injury is preventable, understanding and addressing these hidden factors could potentially reduce risk and build more resilient athletes and individuals.
If you found this analysis useful, please consider subscribing to the Your Wellness Nerd YouTube channel for more evidence-based insights on injury prevention and recovery.
– Grant
Frequently Asked Questions
Can poor ankle mobility really cause an ACL injury?
It's not that ankle stiffness "causes" ACL tears directly, but it creates a mechanical constraint. When the ankle can't move through its full range during dynamic movements, the knee may be forced into compensatory positions - like increased valgus or excessive rotation - that load the ACL more than it's designed to handle.
Should I get my ankle checked even if it doesn't hurt?
Yes. Pain isn't always a reliable indicator of functional restriction. Many people have lost range of motion from old ankle sprains without current pain. A simple test - like measuring how far your knee can travel over your toes - can reveal limitations that may be influencing your knee.
What's the best way to restore ankle mobility after an old injury?
Banded ankle mobilisations (as shown in many of my videos), consistent calf stretching (especially with contract‑relax), and gradually incorporating flat or minimal shoes can help. Working with a physio ensures you're targeting the right structures - sometimes the restriction is in the joint itself, not just the muscles.
One profound insight from this post
"The instant an ACL tears may be the moment that reveals the quality of pre-existing leg mechanics. The ligament might simply be the structure that couldn't tolerate forces generated by hidden restrictions further up or down the chain."
Living With Persistent Pain?
If your pain has lasted longer than expected, feels disproportionate to activity, or hasn't responded to standard treatment, you may benefit from a broader approach. Learn more about our knee pain physiotherapy services in Port Macquarie.
Need Personalised Guidance?
If you'd like help trying to uncover the underlying cause of your pain or dysfunction, consider booking an online Telehealth consultation with Grant!
