ACL Knee Injuries- do you actually need surgery?

Can a Torn ACL Really Heal?

Introducing the Cross Bracing Protocol

Introducing the Cross Bracing Protocol

For years, a torn anterior cruciate ligament (ACL) was seen as a one-way ticket to surgery—especially for active people.

The thinking used to be simple: a torn ACL couldn’t heal—like two ends of a snapped rope flapping around in the knee, with no way to reconnect. But that belief is now being challenged.

In a series of blogs we’ve shared, we have highlighted two very different ACL recovery journeys—one surgical, one non-surgical—and hinted at something that’s really turning heads in sports medicine: the idea that a torn ACL might actually heal on its own.

As physios, this is hugely exciting (geeky, we know).

Our clinic is one of the few in New Zealand trialling the rehab-first Cross Bracing Protocol (CBP). In conjunction with Axis Sports Medicine, we’re currently supporting Patient Number 7 in the Auckland trial—which makes it all feel very real.

Overall, this represents a massive shift in how we can support and offer options to patients facing one of the biggest and most feared sporting injuries we see.

What Does the Research Say?

Emerging studies—particularly from Europe and Australia—are showing that in some cases, a torn ACL can heal with structured rehabilitation, no surgery required. This was unthinkable not that long ago.

• Filbay et al. (2022): Over half of participants with complete ACL ruptures showed signs of healing within 6–12 months, confirmed by MRI. These patients followed a progressive, structured rehab plan with regular check-ins, imaging, and assessments. Importantly, many reported excellent knee function and stability at two-year follow-up—without surgery.

• Rehab-only studies: About 1 in 3 patients managed with physiotherapy alone achieved MRI-confirmed healing, often reporting better function than those who had surgery.

Takeaway: Non-surgical recovery is possible—but it requires early, structured intervention and ongoing support.

What Do the Surgeons Think?

Orthopaedic thinking is shifting too. Some surgeons remain understandably cautious, but more are open to a “wait and see” approach in the right cases—particularly when someone:

• isn’t experiencing instability (knee giving way or buckling)

• isn’t aiming to return to top-level pivoting sports

• is willing to commit to a structured rehab programme and follow-up

Surgery still has an important role. But informed choice is key—and surgery may not be essential for everyone.

What Is the Cross Bracing Protocol (CBP)?

CBP is a structured, non-surgical pathway designed to give a torn ACL the best possible chance to heal naturally.

How it works:

• Initial bracing: The knee is locked in a brace at 90° and kept non-weight-bearing with crutches for at least 4 weeks.

• Progressive stages: Weight-bearing is gradually reintroduced, and the brace is adjusted to allow safe increases in movement.

• Physiotherapy: Strength, stability, and mobility exercises are guided by our physios to support recovery.

• Follow-up MRI: Progress is monitored to confirm healing and help decide if surgery is still needed.

CBP isn’t for everyone—but for the right candidate, the results can be impressive.

Evidence at a Glance:

Studies & their Key Findings

CBP Cohort (Europe/Australia)~90% showed MRI healing at 3 months; better knee function; re-injury ~14%

Rehab-first RCT (KANON)~30% MRI healing at 2 years without special bracing; healed patients reported better function and stability

Ongoing RCTCBP vs early ACL reconstruction — results pending

Patient Story: #7

If you’ve been following our blogs, you’ll know Patient #7 has been on CBP for a torn ACL.

Update: He’s out of the brace, and the 3-month MRI shows signs of natural healing.

Seeing the research work in real time is exciting — for Patient #7, it’s a huge milestone; for us, a glimpse of what the future of ACL rehab might look like.

Follow the full journey in our blog series.