Common Knee Injuries and How to Treat Them

Your knees are the quiet heroes of your everyday life. They carry you upstairs, out of chairs, through long walks, and even longer grocery lines. But when something goes wrong, you realize just how much you depend on them. If you’ve been sidelined by pain or stiffness, it’s time to take a closer look at your knee health and how to get back to doing the things you love.

As a therapist who’s helped many people through knee surgery recovery, I’ve seen the full spectrum of injuries and outcomes. Let’s walk through how the knee works, common ways it gets hurt, and what treatments can help you get your mobility (and your life) back.

Knee Anatomy and Why It Matters for Knee Health

The knee is one of the largest and most complex joints in your body. It connects your thigh bone (femur) to your shin bone (tibia), with help from the fibula and patella (kneecap). But bones are only part of the story.

What keeps your knees strong and steady?

• Ligaments: These include the ACL, PCL, MCL, and LCL, which provide support and keep everything aligned.
• Cartilage: The meniscus absorbs shock and protects the joint.
• Tendons: These connect muscle to bone, especially around the kneecap.

When even one part of this system breaks down, it can throw off your entire movement pattern. That’s why protecting and improving your knee health is essential—whether you’re healing from an injury or trying to prevent one.

The Most Common Knee Injuries (and What You Can Do About Them)

Now that you’ve got a good grasp of what makes up the knee and why knee health matters, let’s get into the injuries that most often put people on the sidelines. From ligament tears to fractures, these are the most common issues that can knock your knees out of commission—and what you can do to bounce back.

ACL Injuries: The Classic Sports Injury

The anterior cruciate ligament (ACL) is one of the most commonly injured parts of the knee, especially in active adults. Quick pivots, sudden stops, or landing awkwardly from a jump can all tear the ACL.

Symptoms

• A “pop” at the time of injury
• Swelling
• Instability
• Difficulty walking

Treatment

Start with the RICE method (Rest, Ice, Compression, Elevation), then move into physical therapy. Surgery may be necessary for complete tears or instability.

PCL Injuries: The Overlooked Ligament

The posterior cruciate ligament (PCL) doesn’t get injured as often as the ACL, but when it does, it affects your knee health just as much. It’s caused by direct blows to the front of the knee, like during a fall or car accident.

Symptoms

• Swelling
• Pain behind the knee
• Difficulty moving or bending the joint

Treatment

Mild injuries may heal with bracing and physical therapy. Severe injuries sometimes require surgery.

MCL and LCL Injuries: Side-to-Side Trouble

The medial and lateral collateral ligaments keep your knee from bending side to side in ways it shouldn’t. It’s caused by lateral blows or twisting forces, and are common in football, skiing, or awkward landings.

Symptoms

• Pain on the inner (MCL) or outer (LCL) side of the knee
• Swelling
• Instability

Treatment

Bracing and rest are usually enough. Physical therapy strengthens the surrounding muscles. Surgery is less common but may be needed for full tears.

Meniscal Tears: The Cushion That Cracks

Your meniscus is like a spongey shock absorber in the knee joint. Once it tears, your knee health can decline quickly without treatment. Meniscal tears are usually caused by sudden twisting or pivoting while bearing weight—think getting up from a squat or turning sharply.

Symptoms

• Clicking, locking, or catching
• Swelling
• Stiffness and pain

Treatment

Minor tears may heal with rest and exercise. Persistent symptoms may need arthroscopic surgery.

Patellar Tendonitis and Tears: Overuse Woes

The patellar tendon connects the kneecap to the shin. When inflamed, it’s called jumper’s knee—a common issue in runners, dancers, and athletes. It’s caused by repetitive jumping, running, or lifting, which strains the tendon over time.

Symptoms

• Pain just below the kneecap
• Swelling
• Soreness when kneeling or squatting

Treatment

RICE is the go-to early on. Stretching, strengthening, and modifying your activity can help. In severe cases, tendon repair surgery may be needed.

Fractures Near the Knee: Sudden and Serious

Knee fractures are less common but extremely disruptive to knee health. High-impact trauma, such as falls or sports injuries, can cause knee fractures.

Symptoms

• Sharp, intense pain
• Swelling and bruising
• Inability to move the leg or bear weight

Treatment

Fractures often require surgery followed by a long rehabilitation process.

When Your Knee Is Trying to Tell You Something

You don’t have to be an expert to know when something’s not right. Watch out for these red flags:

• Persistent pain that interferes with daily life
• Swelling that doesn’t improve
• Popping or grinding sounds associated with pain
• A feeling that your knee might "give out"

If these symptoms sound familiar, don’t wait it out. Early intervention makes a huge difference in long-term knee health and function.

How to Protect and Improve Your Knee Health Every Day

Whether you’re healing from an injury or trying to stay ahead of one, these simple habits can go a long way:

• Strengthen your legs: Your quads, hamstrings, and glutes are your knee’s best friends.
• Stretch regularly: Especially your hamstrings, calves, and hip flexors.
• Warm up before activity: A few dynamic moves can prep your joints for movement.
• Wear proper footwear: Supportive shoes help with alignment and reduce stress on the knees.
• Maintain a healthy weight: Less weight on your joints means less wear and tear over time.

Rehab programs that include guided exercises and joint mobilization techniques can play a major role in improving knee health—these programs help make it easier to stay consistent at home. Remember, being kind to your knees doesn’t mean giving up movement—it means moving smarter.

Move Forward with Better Knee Health

If your knees are hurting, it’s not just about getting rid of the pain—it’s about getting your life back. Staying informed, taking action, and seeking support when needed are the most powerful things you can do for your long-term knee health.

The journey might feel long, but you don’t have to walk it alone. And trust me, it’s worth it when you start moving freely again—whether that means hiking up your favorite trail, dancing at your kid’s wedding, playing pickleball with friends or just getting out of the car without wincing.

Good luck on your knee journey!

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