8 Common Knee Injuries from Falling: Diagnosis and Treatment

Falling is a fast, chaotic physics experiment you definitely didn’t sign up for. One second you’re walking like a responsible adult, the next you’re doing an unplanned interpretive dance with gravityand your knee is the one paying the cover charge.

The tricky part: a fall can cause anything from a harmless bruise to a fracture or ligament injury that needs urgent care. This guide breaks down 8 common knee injuries from falling, what doctors look for during knee injury diagnosis, and the usual treatment pathsso you can spend less time doom-googling and more time healing.

Important: This is general educational info, not personal medical advice. If you’re worried, get checkedknees don’t come with a “restart” button.

When a Knee Injury After a Fall Is an ER/Urgent Care Situation

Seek urgent evaluation if you notice any of the following after a fall:

• You can’t bear weight or you feel like the knee will collapse.
• Visible deformity (kneecap looks “out of place”) or the knee looks misshapen.
• Rapid, major swelling within hours, or swelling that keeps getting worse.
• Locked knee (you can’t fully bend or straighten it).
• Numbness, cold foot, or color change in the lower leg/foot.
• Severe pain that doesn’t improve with rest/ice.

How Doctors Diagnose Knee Injuries After a Fall

Most knee evaluations start with a detective story: what happened, where it hurts, and what you can’t do now that you could do before the fall. Then comes a physical exam to check:

• Range of motion (can you bend/straighten?)
• Stability (do ligaments feel loose?)
• Tenderness points (bone vs. soft tissue clues)
• Swelling patterns (slow swelling can differ from sudden swelling)

Do you need an X-ray or MRI?

Not alwaysbut sometimes absolutely. Clinicians often use decision tools (like the Ottawa Knee Rule) to decide when an X-ray is needed to check for fracture. If a fracture is suspected, X-rays are typically first. An MRI is usually reserved for suspected ligament, meniscus, cartilage, or bone bruise problemsespecially if X-rays are normal but symptoms persist.

First-aid basics while you’re figuring it out

For many minor injuries, early care is the classic RICE approachrest, ice, compression, and elevationplus sensible activity modification. If you’re limping, consider using a cane/crutch temporarily rather than powering through like it’s a reality show.

1) Knee Contusion (Bruise) or Bone Bruise (Bone Contusion)

What it is: A knee contusion is bruising of skin/muscle from impact. A bone bruise is a deeper injury to the bone beneath the cartilageoften painful, sometimes stubborn.

Common fall scenario

You land directly on the front or side of your knee (tile floors: undefeated champions of impact).

Symptoms

• Localized pain and tenderness
• Visible bruising and swelling
• Pain with kneeling, squatting, or stairs
• Bone bruises can ache longer than you’d expect

Diagnosis

Most simple bruises are diagnosed clinically. If pain is intense, swelling is large, or weight-bearing is difficult, clinicians may order imaging. Bone bruises are best seen on MRI.

Treatment

• RICE for the first 24–72 hours
• Gradual return to motion (stiffness is not your friend)
• Physical therapy if pain/limping lingers
• If symptoms worsen or don’t improve, re-check for hidden injuries

2) Meniscus Tear

What it is: The meniscus is cartilage that cushions your knee joint. A tear can happen when the knee twists under loadeven during a fall where your foot sticks and your body rotates.

Common fall scenario

You slip, your foot stays planted, and your knee twists. The fall itself may feel “meh” until the knee starts complaining later.

Symptoms

• Pain along the joint line (often inner or outer side)
• Swelling and stiffness that may increase over a day or two
• Catching, clicking, or locking
• Feeling like the knee might “give way”

Diagnosis

Physical exam maneuvers plus your story are key. X-rays may be used to rule out fracture or arthritis; MRI can confirm a tear.

Treatment

• Conservative: rest, activity modification, anti-inflammatory options (when appropriate), and physical therapy
• Procedures: some tears may be treated with arthroscopy (repair vs. trimming depends on tear type/location)
• Goal: restore motion, strength, and stable mechanicsso your knee stops acting like it’s auditioning for drama.

3) Medial Collateral Ligament (MCL) Sprain

What it is: The MCL supports the inner side of the knee. A sprain happens when the ligament is stretched or tornoften from a sideways force.

Common fall scenario

You fall and your knee collapses inward, or you twist awkwardly while trying to “save” the fall (a heroic move that rarely ends well).

Symptoms

• Pain on the inner side of the knee
• Swelling and tenderness
• Feeling of instability with side-to-side movement

Diagnosis

Physical exam focuses on ligament stability testing. Imaging may be used if fracture or additional injuries are suspected.

Treatment

• Most MCL injuries improve without surgery
• Hinged knee brace + physical therapy is common
• Return to sport/work depends on grade of sprain and function

4) Anterior Cruciate Ligament (ACL) Injury

What it is: The ACL stabilizes the knee, especially with pivoting and sudden direction changes. Although ACL tears are famous in sports, a bad fall with twisting can do it too.

Common fall scenario

A twisting fall where your shin shifts forward under you, especially if you land with the knee bent and rotate.

Symptoms

• A “pop” sensation (not always)
• Swelling, often within hours
• Instability: the knee feels unreliable, especially with turning
• Difficulty returning to pivoting activities

Diagnosis

Exam tests knee stability. X-rays may rule out fracture; MRI helps confirm ACL injury and check for meniscus/cartilage damage.

Treatment

• Rehab first is common: physical therapy to reduce swelling, restore motion, and build strength
• Bracing/crutches may help temporarily
• Surgery may be recommended for ongoing instability or high-demand athletes, followed by structured rehab

5) Patellar Dislocation or Subluxation (Kneecap Slips Out of Place)

What it is: The kneecap (patella) normally glides in a groove. A fall can cause it to partially slip out (subluxation) or fully dislocate.

Common fall scenario

You twist while falling, and the kneecap shiftsoften to the outside. Sometimes it pops back in on its own; sometimes it doesn’t.

Symptoms

• Sudden pain at the front of the knee
• Visible kneecap “out of place” (in dislocation)
• Swelling and difficulty bending/straightening
• Feeling of instability afterward

Diagnosis

Clinicians examine alignment and stability. Imaging can check for fracture or cartilage injury, especially after a dislocation.

Treatment

• Rest, ice, pain control, and short-term immobilization may be used
• Physical therapy focuses on hip/thigh strength and kneecap tracking
• Recurrent instability may need specialist evaluation; some cases require surgery

6) Prepatellar Bursitis (Traumatic “Kneecap Bursitis”)

What it is: A bursa is a fluid-filled cushion. The prepatellar bursa sits in front of the kneecap. Direct impact from a fall can inflame it, causing swelling right over the kneecap.

Common fall scenario

You land directly on the front of your knee. The next day, it looks like you’re smuggling a small water balloon under your skin.

Symptoms

• Swelling over the kneecap
• Tenderness and warmth
• Pain with kneeling

Diagnosis

Often clinical. If there’s redness, fever, or significant warmth, clinicians may consider infection and evaluate further.

Treatment

• Rest, ice, elevation; avoid kneeling
• Compression may help
• If infection is suspected or swelling persists, medical evaluation is important (sometimes aspiration/medications are needed)

7) Patellar Fracture (Broken Kneecap)

What it is: A patellar fracture is a break in the kneecap, commonly from a direct blowlike landing on the knee during a fall.

Common fall scenario

Direct impact: falling forward onto the kneecap, or striking the knee against a hard surface.

Symptoms

• Significant pain and swelling
• Trouble straightening the knee
• Difficulty walking/standing
• Bruising and tenderness over the kneecap

Diagnosis

X-rays are standard. The clinician also checks the “extensor mechanism” (whether you can do a straight-leg raise), because that affects treatment decisions.

Treatment

• Non-surgical (some cases): immobilization in a brace/splint if fracture pieces are stable
• Surgical (many cases): if pieces are displaced or knee extension mechanism is disrupted
• Rehab afterward focuses on safe motion and strength restoration

8) Tibial Plateau / Proximal Tibia Fracture (Top of the Shinbone)

What it is: The tibial plateau is the upper surface of the shinbone where it forms the knee joint. A fracture here can affect the joint surface and is more serious than a simple bruise.

Common fall scenario

A fall from height, a hard landing, or a twisting fall with compressionespecially if you land with weight on a bent knee.

Symptoms

• Severe pain and swelling
• Inability to bear weight
• Stiffness, reduced motion
• Sometimes deformity or instability

Diagnosis

X-rays are typical first. CT may help define the fracture pattern; MRI may be used to check associated meniscus/ligament injuries.

Treatment

• Non-surgical for select stable fractures: bracing and strict weight-bearing limits
• Surgical for displaced/unstable fractures: fixation to restore joint alignment
• Physical therapy is crucial but timed carefully to protect healing bone

Rehab: The Part Everyone Wants to Skip (But Shouldn’t)

Whether your injury is “just a sprain” or something bigger, recovery usually hinges on the same boring-but-effective basics:

• Restore motion early (when safe) to avoid stiffness.
• Build strength in quads, hamstrings, hips, and core for better knee control.
• Retrain balance so your body stops repeating the same fall pattern.
• Progress gradually (pain and swelling are feedback, not challenges).

How to Talk to a Clinician So You Get a Better Answer Faster

Bring specifics. “My knee hurts” is true, but it’s also what knees say about literally everything. Instead, try:

• “I fell on December 29 and landed directly on the kneecap.”
• “Swelling started within 2 hours and keeps increasing.”
• “It locks when I try to straighten.”
• “I can/can’t bear weight. Stairs are impossible.”
• “I heard/felt a pop.”

Experiences After a Knee-Fall Injury (What People Commonly Report)

To make this topic feel less like a textbook and more like real life, here are experiences many patients describe after a fall-related knee injury. Not everyone will match these stories, but they highlight patterns clinicians hear every day.

The “I’m fine… wait, I’m not” moment: A lot of people stand up immediately after a fall and walk it offbecause adrenaline is a powerful motivational speaker. Then later (sometimes that evening, sometimes the next day) swelling and stiffness move in like they pay rent. This is especially common with meniscus irritation, ligament sprains, and bone bruises. People often say, “It didn’t hurt that much at firstthen it got worse.” The delayed swell can be confusing, so it’s worth tracking when symptoms start and how they change.

The stairs betrayal: Even mild knee injuries tend to announce themselves on stairs. Folks describe going down steps as the worst (because it loads the knee while it’s bent). With bruises and bursitis, it’s the pressure and impact. With ligament injuries, it’s the sense that the knee doesn’t trust itself. With meniscus issues, stairs can trigger catching or sharp painlike the knee briefly “argues” with your plan to move normally.

The “why does it feel wobbly?” phase: After an MCL or ACL injury, people commonly describe the knee as “loose,” “shifty,” or “not solid.” Sometimes they avoid turning quickly, stepping off curbs, or walking on uneven ground because they don’t trust the joint. This loss of confidence can be as limiting as painand it’s one reason rehab focuses so heavily on strength and balance. When your muscles and nervous system re-learn how to stabilize the knee, the wobble often improves.

The swollen kneecap surprise: After a direct fall onto the front of the knee, some people notice a distinct puffiness right over the kneecap. It can look dramatic and feel tender, especially with kneeling. Many describe it as “squishy” rather than deep joint swelling. That pattern can fit prepatellar bursitis, and the experience often pushes people to seek care because it looks alarmingeven when the underlying issue is treatable with conservative steps.

The long-haul annoyance of bone bruises: Bone bruises can be a patience test. People often report that they can walk, but impact activities (running, jumping, even long walks) trigger a deep ache that lingers. The frustration usually isn’t “I can’t move,” but “Why is this still here?” Rehab and activity pacing matter a lotdoing too much too soon can keep symptoms smoldering.

The turning point: Many people describe a clear “better week” once swelling drops and motion returnsoften after they stop testing the knee with heroic squats and start following a steady plan: gentle mobility, progressive strengthening, and smarter rest. It’s not glamorous, but it’s effective. And yes, the knee often improves right around the time you finally admit that ice and elevation aren’t just suggestions.

Conclusion

A fall can trigger many different knee injuriesfrom bruises and bursitis to ligament tears and fractures. The key is matching the symptom pattern (pain location, swelling timing, instability, locking) with the right evaluation and imaging when needed. Most injuries improve with a thoughtful plan: early protection, guided rehab, and a gradual return to activity. And if your knee is waving red flagscan’t bear weight, looks deformed, locks, or swells rapidlyget checked promptly. Your future self (and your stairs) will thank you.