Knee Pain on Pressure: Understanding Causes and When to Seek Help

Why does my knee hurt when I press on it?

Experiencing knee pain when pressure is applied often indicates irritation or inflammation of the structures directly beneath the skin or within the joint capsule, ranging from soft tissue injuries and overuse syndromes to degenerative conditions or, less commonly, more serious issues.

Understanding Your Knee's Anatomy

To understand why your knee might hurt when pressed, it's essential to briefly recall its complex structure. The knee is a hinge joint, but its function is far more intricate, involving:

• Bones: The femur (thigh bone), tibia (shin bone), and patella (kneecap).
• Cartilage: Smooth articular cartilage covers the ends of the bones, allowing them to glide friction-free. The menisci are C-shaped cartilage pads that act as shock absorbers and improve joint stability.
• Ligaments: Strong, fibrous bands that connect bones and provide stability (e.g., ACL, PCL, MCL, LCL).
• Tendons: Connect muscles to bones (e.g., quadriceps tendon, patellar tendon).
• Bursae: Small, fluid-filled sacs that reduce friction between bones, tendons, and muscles.
• Synovial Membrane: Lines the joint, producing synovial fluid for lubrication.
• Fat Pads: Cushions, such as Hoffa's fat pad located behind the patellar tendon.

Pain on direct pressure (palpation) typically points to a localized issue with one or more of these structures.

Common Causes of Knee Pain on Pressure

Identifying the exact location and nature of the pain is crucial for diagnosis. Here are the most common culprits:

• Bursitis: Inflammation of one of the bursae around the knee.
  • Prepatellar Bursitis ("Housemaid's Knee"): Pain and swelling directly on the front of the kneecap, often from kneeling.
  • Infrapatellar Bursitis ("Clergyman's Knee"): Pain and swelling just below the kneecap, over the patellar tendon insertion.
  • Pes Anserine Bursitis: Pain on the inside of the knee, a few inches below the joint line, where three hamstring tendons attach.
• Patellar Tendinopathy ("Jumper's Knee"): Inflammation or degeneration of the patellar tendon, which connects the kneecap to the shin bone.
  • Pain is typically localized to the bottom of the kneecap or just below it, often tender to touch, especially at its attachment point. Aggravated by jumping, running, or squatting.
• Patellofemoral Pain Syndrome (PFPS) / "Runner's Knee": A common condition causing pain around or behind the kneecap.
  • While often diffuse, direct pressure on the edges of the patella or palpation around the kneecap can elicit pain, particularly if there's irritation of the underlying cartilage or synovial tissue.
• Meniscus Tear: A tear in the C-shaped cartilage pads within the knee joint.
  • Pain is often localized to the joint line (the space between the femur and tibia) and can be tender when pressed directly over the tear. May also present with clicking, locking, or instability.
• Ligament Sprain: Injury to the ligaments that stabilize the knee.
  • While often associated with instability, a sprained ligament (e.g., MCL on the inner side, LCL on the outer side) can be very tender when pressed directly over the injured fibers.
• Osteoarthritis: Degenerative "wear and tear" of the articular cartilage.
  • As cartilage breaks down, the underlying bone can become inflamed, leading to pain that can be exacerbated by direct pressure, especially over the joint lines or patella.
• Fat Pad Impingement (Hoffa's Syndrome): Inflammation or impingement of Hoffa's fat pad, located behind the patellar tendon.
  • Pain is typically deep, just below the kneecap, and can be very tender when pressed, especially if the knee is slightly extended.
• Plica Syndrome: Irritation of the plica, which are folds in the synovial membrane.
  • If inflamed, a plica can become thickened and painful, often tender to palpation along the medial (inner) aspect of the kneecap.
• Osgood-Schlatter Disease (in adolescents): Inflammation of the growth plate at the top of the shin bone where the patellar tendon attaches.
  • Causes a painful bony lump just below the kneecap that is very tender to touch.

Less Common, But Serious Causes

While less frequent, some conditions causing knee pain on pressure warrant immediate medical attention:

• Infection (Septic Arthritis): A bacterial infection within the joint. Presents with severe pain, swelling, redness, warmth, and often fever. The joint will be exquisitely tender to touch.
• Fracture: A break in one of the knee bones (patella, tibia, femur). Localized tenderness is a hallmark symptom, often accompanied by significant pain, swelling, and inability to bear weight. Stress fractures can cause localized tenderness without obvious trauma.
• Tumor: Very rare, but a bone tumor or soft tissue mass around the knee can cause localized pain and tenderness, often progressive and worse at night.

When to Seek Medical Attention

While many causes of knee pain on pressure can resolve with rest and self-care, it's important to consult a healthcare professional if you experience:

• Severe pain that prevents weight-bearing.
• Significant swelling or redness around the knee.
• Deformity of the knee or leg.
• Audible pop or snap at the time of injury.
• Inability to bend or straighten the knee.
• Numbness or tingling in the lower leg or foot.
• Fever, chills, or general malaise accompanying the knee pain.
• Pain that worsens or doesn't improve after a few days of self-care.
• Pain that wakes you at night.

Initial Self-Care and Management

For mild, acute knee pain without red flag symptoms, the R.I.C.E. protocol can be beneficial:

• Rest: Avoid activities that aggravate the pain.
• Ice: Apply ice packs to the affected area for 15-20 minutes, several times a day, to reduce inflammation and pain.
• Compression: Use an elastic bandage or knee sleeve to help reduce swelling.
• Elevation: Keep your knee elevated above your heart to minimize swelling.

Over-the-counter pain relievers (NSAIDs like ibuprofen) can also help manage pain and inflammation.

Prevention Strategies

Reducing the risk of knee pain, especially from overuse, involves:

• Proper Warm-up and Cool-down: Prepare your muscles and joints for activity and aid recovery.
• Gradual Progression: Increase the intensity, duration, or frequency of your workouts slowly.
• Strength Training: Focus on strengthening the muscles surrounding the knee (quadriceps, hamstrings, glutes, calves) to provide better support.
• Flexibility and Mobility: Maintain good range of motion in your hips, knees, and ankles.
• Proper Footwear: Wear supportive shoes appropriate for your activity.
• Listen to Your Body: Don't push through pain. Address minor aches before they become major injuries.

Conclusion

Knee pain when pressed is a common symptom with a wide range of potential causes, primarily involving irritation or inflammation of superficial or intra-articular structures. While many cases are manageable with conservative care, understanding the underlying anatomy and recognizing warning signs are crucial. Consulting a healthcare professional or a physical therapist/kinesiologist for an accurate diagnosis and tailored treatment plan is always recommended for persistent or severe symptoms.