Can you live a normal life without an ACL?

What happens to the knee without an ACL?

The anterior cruciate ligament does not heal on its own after a complete tear in most cases. Without it, the knee can be less stable during sudden twisting, stopping and cutting movements. Some people experience episodes of giving way, while others adapt well, particularly with strong thigh and hip muscles and good neuromuscular control.

Everyday activities such as walking, cycling, swimming, running in straight lines and many gym exercises are possible for most people without an ACL after rehabilitation.

Does early surgery give better results than rehabilitation?

A randomised trial in Sweden included 121 young, active adults with an acute ACL tear 1. All received structured rehabilitation. One group had early ACL reconstruction, and the other had rehabilitation with the option of delayed reconstruction if needed. At two years, the improvement in knee scores was 39.2 points with early reconstruction and 39.4 points with optional delayed reconstruction, with no significant difference 1.

At five years, the improvement was 42.9 and 44.9 points respectively, again with no significant difference 2. In the optional group, 30 people, or 51 per cent, had delayed reconstruction by five years, meaning the other half managed without surgery 2. There were no differences in osteoarthritis on X-ray or meniscus surgery between groups 2.

Who is more likely to need reconstruction?

Reconstruction is more often recommended for people who want to return to sports involving jumping, pivoting and cutting, such as football, basketball or skiing, for people whose knee continues to give way despite good rehabilitation, and when the ACL tear is combined with other injuries, such as a repairable meniscus tear.

Some people prefer early reconstruction for career or sporting reasons. The decision is personal and should be made after discussing the evidence, goals and risks with a knee specialist.

What does rehabilitation without surgery involve?

Rehabilitation without surgery follows many of the same principles as rehabilitation after reconstruction: restoring full knee movement, reducing swelling, rebuilding quadriceps and hamstring strength, and training balance, landing and change-of-direction control.

Programmes usually last several months. Progress is monitored with strength and hop tests and by whether the knee gives way. If instability persists, reconstruction can still be considered later.

Can living without an ACL lead to arthritis?

ACL injuries increase the long-term risk of knee osteoarthritis whether or not the ligament is reconstructed. Associated injuries to the meniscus and cartilage at the time of injury contribute to this risk.

In the Swedish trial, radiographic osteoarthritis at five years did not differ between people who had early reconstruction and those offered rehabilitation with optional delayed reconstruction 2. Maintaining strength, a healthy weight and avoiding repeated giving-way episodes help protect the knee.

How are strength and hop tests used?

Before returning to demanding activities, clinicians often compare the injured and uninjured legs using strength tests for the thigh muscles and a series of hop tests, such as hopping for distance or hopping several times in a row. Movement quality during landing and changing direction is also observed.

These tests help identify remaining deficits and guide training. Passing tests does not remove all risk, but large differences between legs suggest that more rehabilitation is needed before returning to pivoting sport.

Which symptoms suggest the knee needs review?

Repeated episodes of the knee giving way, new swelling after activity, locking or catching, or persistent pain should be reviewed, as they may indicate instability or a new meniscus injury.

Each giving-way episode can damage the meniscus and cartilage, so recurrent instability is an important reason to reconsider the treatment plan.

Frequently asked questions