Pain Below the Knee: Causes, Symptoms, and Management

Why there is pain below my knee?

Pain below the knee often stems from issues with tendons, ligaments, bones, or muscles in the lower leg, frequently caused by overuse, trauma, or biomechanical imbalances impacting the knee joint and surrounding structures.

Understanding the Anatomy Below the Knee

The region directly below the knee is a complex intersection of bone, muscle, tendon, and ligamentous structures, all working in concert to facilitate movement, absorb shock, and provide stability. Understanding these components is crucial for identifying potential sources of pain. Key structures include:

• Bones: The tibia (shin bone) forms the primary weight-bearing bone extending from the knee down to the ankle. The fibula is a smaller, parallel bone on the outer side of the lower leg, primarily serving as an attachment point for muscles and ligaments.
• Tendons: Strong fibrous cords that connect muscle to bone. Notable tendons below the knee include the patellar tendon (connecting the kneecap to the tibial tuberosity on the front of the tibia), and the tendons of the hamstring muscles (semimembranosus, semitendinosus, biceps femoris) which attach around the knee, particularly the pes anserine group on the inner side.
• Muscles: Major muscle groups in the lower leg, such as the quadriceps (via the patellar tendon), hamstrings, gastrocnemius and soleus (calf muscles), tibialis anterior (front of shin), and peroneals (outer lower leg), all play a role in knee and ankle movement and can be sources of referred pain.
• Bursae: Small, fluid-filled sacs that reduce friction between bones, tendons, and muscles. The pes anserine bursa on the inner side of the knee is a common site of inflammation.
• Nerves and Blood Vessels: Nerves like the common peroneal nerve and various blood vessels supply the lower leg, and their impingement or injury can cause pain.

Common Causes of Pain Below the Knee

Pain below the knee is frequently due to overuse injuries, direct trauma, or biomechanical issues.

• Patellar Tendinopathy (Jumper's Knee):

  • Description: Inflammation or degeneration of the patellar tendon, typically at its attachment point on the tibial tuberosity (the bony bump below the kneecap).
  • Cause: Repetitive stress from activities involving jumping, running, or deep knee bends, leading to micro-tears in the tendon.
  • Symptoms: Localized pain directly below the kneecap, often worse with activity, kneeling, or stair climbing.

• Osgood-Schlatter Disease:

  • Description: A common cause of knee pain in growing adolescents, characterized by inflammation of the patellar tendon at its insertion onto the tibial tuberosity.
  • Cause: Repetitive traction from the quadriceps muscle pulling on the patellar tendon during periods of rapid growth and high activity.
  • Symptoms: Pain, swelling, and tenderness at the tibial tuberosity, often with a noticeable bump. Worsens with activity.

• Shin Splints (Medial Tibial Stress Syndrome - MTSS):

  • Description: Diffuse pain along the inner lower leg, often along the tibia.
  • Cause: Overuse, sudden increase in running mileage or intensity, inadequate footwear, poor biomechanics (e.g., overpronation).
  • Symptoms: Aching or throbbing pain along the inner aspect of the shin, worse during or after exercise.

• Stress Fractures (Tibia or Fibula):

  • Description: Tiny cracks in the bone, most commonly the tibia, due to repetitive stress.
  • Cause: Gradual increase in impact activities (running, marching), insufficient recovery, poor nutrition, or underlying bone density issues.
  • Symptoms: Localized, sharp pain that worsens with activity and often improves with rest. Pinpoint tenderness over the affected bone.

• Pes Anserine Bursitis/Tendinopathy:

  • Description: Inflammation of the bursa or tendons where the sartorius, gracilis, and semitendinosus muscles attach to the inner side of the tibia, a few inches below the knee joint.
  • Cause: Overuse, tight hamstrings, obesity, osteoarthritis of the knee, or a valgus (knock-kneed) alignment.
  • Symptoms: Pain and tenderness on the inner, lower side of the knee, often worse with climbing stairs or getting up from a chair.

• Calf Muscle Strain/Tear:

  • Description: Damage to the gastrocnemius or soleus muscles in the calf.
  • Cause: Sudden forceful contraction, overstretching, or inadequate warm-up.
  • Symptoms: Sharp pain in the calf, which can sometimes be felt radiating towards the knee, swelling, bruising, and difficulty with ankle movements.

• Fibular Head Pain/Peroneal Tendinopathy:

  • Description: Pain around the fibular head (the bony prominence on the outer side of the knee) or along the peroneal tendons.
  • Cause: Direct trauma, repetitive ankle instability, or overuse of the peroneal muscles (which evert the foot).
  • Symptoms: Pain, tenderness, and sometimes swelling on the outer aspect of the knee or lower leg.

Less Common or More Serious Causes

While less frequent, certain conditions causing pain below the knee require prompt medical attention.

• Compartment Syndrome (Acute/Chronic):

  • Description: A serious condition where increased pressure within a muscle compartment restricts blood flow. Acute is a medical emergency; chronic is often exercise-induced.
  • Cause: Trauma (acute), or repetitive exercise causing muscle swelling (chronic).
  • Symptoms: Severe pain disproportionate to the injury, tightness, numbness, tingling, or weakness in the foot.

• Nerve Entrapment (e.g., Common Peroneal Nerve):

  • Description: Compression or irritation of a nerve, such as the common peroneal nerve as it wraps around the fibular head.
  • Cause: Trauma, prolonged pressure, or swelling.
  • Symptoms: Numbness, tingling, burning pain, or weakness in the outer lower leg and foot (foot drop).

• Deep Vein Thrombosis (DVT):

  • Description: A blood clot forms in a deep vein, usually in the lower leg.
  • Cause: Prolonged immobility, surgery, certain medical conditions, or trauma.
  • Symptoms: Swelling, warmth, redness, and pain in the calf/lower leg. This is a medical emergency.

• Referred Pain:

  • Description: Pain originating from another area, such as the knee joint itself (e.g., meniscal tear, osteoarthritis, ligamentous injury) or even the hip or lower back, can be perceived below the knee.
  • Cause: Degenerative changes, injury, or nerve impingement higher up the kinetic chain.

• Infection (Osteomyelitis, Cellulitis):

  • Description: Bacterial or fungal infection of the bone (osteomyelitis) or skin/soft tissue (cellulitis).
  • Cause: Open wounds, surgery, or spread from other infections.
  • Symptoms: Redness, warmth, swelling, severe pain, fever, chills, and general malaise.

When to Seek Medical Attention

While many cases of pain below the knee can be managed with self-care, it's crucial to consult a healthcare professional if you experience:

• Severe pain that prevents weight-bearing or normal activity.
• Sudden swelling, redness, or warmth in the lower leg.
• Numbness, tingling, or weakness in the foot or toes.
• Pain accompanied by a fever or chills.
• Pain that results from a direct, significant trauma and is accompanied by a popping sound or visible deformity.
• Pain that worsens or doesn't improve within a few days of rest and self-care.
• Signs suggestive of DVT (unilateral calf swelling, redness, warmth, pain).

Initial Self-Care and Management Strategies

For mild to moderate pain, initial management can often begin at home.

• R.I.C.E. Principle:
  • Rest: Avoid activities that worsen the pain.
  • Ice: Apply ice packs to the affected area for 15-20 minutes, several times a day.
  • Compression: Use a compression bandage to reduce swelling.
  • Elevation: Elevate the leg above heart level when resting.
• Activity Modification: Reduce the intensity, duration, or frequency of activities that aggravate the pain. Gradually reintroduce activities as pain subsides.
• Appropriate Footwear: Ensure your shoes provide adequate support and cushioning, especially for athletic activities. Replace worn-out shoes.
• Over-the-Counter Pain Relief: Non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or naproxen can help manage pain and inflammation, but should be used cautiously and as directed.
• Gentle Stretching and Strengthening: Once acute pain subsides, focus on gentle stretching for tight muscles (e.g., hamstrings, calves, quadriceps) and strengthening exercises for the surrounding musculature (quads, hamstrings, glutes, core) to improve stability and address imbalances.

Prevention Through Biomechanical Awareness

Preventing pain below the knee often involves smart training practices and addressing biomechanical factors.

• Progressive Overload: Gradually increase the intensity, duration, or volume of your workouts to allow your body to adapt. Avoid sudden spikes in training.
• Proper Warm-up and Cool-down: Always begin workouts with a dynamic warm-up and finish with a static cool-down to prepare muscles and tendons for activity and aid recovery.
• Strength and Flexibility Balance: Incorporate exercises that strengthen both the front and back of your thighs, as well as your glutes and core. Address any muscle imbalances and maintain good flexibility.
• Cross-Training: Vary your exercise routine to avoid repetitive stress on the same structures.
• Listen to Your Body: Pay attention to early warning signs of pain or discomfort. Pushing through pain can lead to more serious injuries.
• Biomechanics Assessment: If you frequently experience pain, consider a professional assessment of your running form or movement patterns by a physical therapist or kinesiologist. They can identify and help correct gait abnormalities, muscle imbalances, or footwear issues.

Conclusion

Pain below the knee is a common complaint with a wide array of potential causes, ranging from benign overuse injuries to more serious medical conditions. While many cases can be managed effectively with rest and self-care, understanding the underlying anatomy and common injury mechanisms is key to effective prevention and treatment. Always prioritize listening to your body, gradually progressing your activity levels, and seeking professional medical advice if pain is severe, persistent, or accompanied by concerning symptoms. A timely and accurate diagnosis is crucial for effective management and a successful return to activity.