Early Signs You Might Have an ACL Injury (and When to See a Doctor)

October 16, 2025

The Anterior Cruciate Ligament (ACL) is one of the key stabilizing ligaments in your knee. It connects your femur (thigh bone) to your tibia (shin bone), and helps prevent excessive forward movement and rotation of the tibia relative to the femur. An injury to the ACL, whether a tear or stretch, can lead to pain, instability, and long-term joint problems if not managed properly.

Because ACL injuries are common in athletes and active people, recognizing the early warning signs is crucial. Catching it early can make a significant difference in treatment and recovery. Below is a detailed look at the telltale signs and when you should see a specialist—such as Dr. Deepak Mishra, a well-known orthopedic surgeon in Faridabad.

What Happens in an ACL Injury?

An ACL injury often occurs from sudden twisting, pivoting, or a direct blow to the knee. It may be a:

Partial tear — some fibers are damaged but the ligament is not completely severed
Complete tear/rupture — the ligament is fully torn or torn in multiple places
Stretch (sprain) — the ligament is overstretched but intact

Many ACL injuries are accompanied by damage to other structures, like the meniscus, articular cartilage, or other knee ligaments.

Early Signs & Symptoms to Watch For

Here are some common early warning signs that might suggest an ACL injury:

Sign / Symptom	What You Might Experience	Why It Happens
A “pop” or a snapping sound	Right at the moment of injury, you might hear or feel a pop in the knee.	The ligament fibers give way or rupture.
Sudden pain, sometimes severe	The pain might be intense enough to force you to stop moving or bear weight.	Inflammation, micro-tears, or bleeding in the joint contribute to pain.
Rapid swelling / joint effusion	Within a few hours, the knee might swell significantly (accumulation of fluid or blood).	Bleeding inside the joint (hemarthrosis) or inflammation.
Reduced range of motion / stiffness	You may find it difficult to fully bend or straighten your knee.	Swelling and pain restrict motion.
Instability / feeling of “giving way”	The knee may feel unstable, weak, or like it will buckle when you step or twist.	The torn or compromised ACL can’t control tibial motion well.
Difficulty continuing activity / inability to bear weight	You may not be able to walk normally or continue your sport or movement.	Pain, instability, and swelling together make load-bearing unsafe.
Other secondary signs	Bruising around the knee, other ligament or meniscus symptoms (locking, catching)	ACL injuries often accompany other knee injuries.

Some injuries may present more subtly—milder pain, occasional instability, or minimal swelling. But don’t ignore even mild signs if they follow trauma or awkward knee movement.

Why Early Detection Matters

Prevents further damage: An unstable knee can cause damage to cartilage, menisci, or other ligaments.
Better healing options: Partial tears caught early might be addressed more conservatively or with less invasive surgery.
Faster recovery: Early diagnosis and initiation of proper therapy often lead to better outcomes.
Reduced risk of long-term problems: Untreated ACL injuries may contribute to early osteoarthritis or chronic knee issues.

How Is It Diagnosed?

When you see a doctor, here’s typically what happens:

History & Physical Exam
The clinician will ask how the injury happened, your symptoms, and then perform special tests like the Lachman test, anterior drawer test, and pivot shift test to assess laxity and instability.
Imaging
- X-ray: to rule out fractures or bone involvement
- MRI: the gold standard to visualize ligament damage and associated injuries (meniscus, cartilage)
Arthroscopic evaluation (in some cases)
A small scope may be used to look inside the joint, confirm damage, and sometimes perform repair.

Treatment Basics

Treatment depends on the severity, your activity level, age, and associated injuries:

Conservative / Non-surgical
In milder cases or lower-demand patients, physical therapy, bracing, and activity modification may suffice.
Surgical reconstruction
For complete tears or active patients, ACL reconstruction (using tendon grafts) is common.
Rehabilitation
Post-treatment, intensive physiotherapy is essential to restore strength, flexibility, balance, and function.

When Should You See a Doctor (Or an Orthopedic Specialist)?

You should seek medical attention immediately if:

You heard a pop, followed by pain or swelling.
You can’t bear weight on the knee.
The knee feels unstable or is “giving out.”
Swelling develops rapidly (within hours).
You notice restricted movement or inability to fully bend/straighten the knee.
Symptoms persist beyond a few days with no improvement.

Delaying evaluation may allow further damage to the knee structures, making repair more complicated.

Why Dr. Deepak Mishra Is a Name to Consider in Faridabad

If you’re in or near Faridabad and suspect an ACL injury, one name frequently mentioned is Dr. Deepak Mishra. Here’s why:

He has over 26 years of experience in orthopedic surgery, specializing in knee and hip replacements, arthroscopy, and joint reconstruction.
He holds credentials such as MBBS and MS (Orthopaedics) from JIPMER, Pondicherry, and has had advanced training including in the UK.
Dr. Mishra is the Director & Head of Orthopaedics, Unit I at Asian Institute of Medical Sciences, Faridabad.
His practice covers arthroscopic surgery, ligament reconstruction (including ACL), joint replacement, and trauma surgery.
He is widely regarded in local listings and medical directories as a top orthopaedic expert in Faridabad and the Delhi NCR region.

Because ACL injuries involve delicate knee structures, selecting a surgeon with strong experience in knee and ligament reconstruction is vital — and Dr. Mishra fits that description for many in the Faridabad area.