Knee Disorders and Diseases

1. Degenerative Diseases

These occur due to wear and tear, often associated with aging.

a) Osteoarthritis (OA)

Cause: Degeneration of cartilage in the knee
Symptoms: Pain, stiffness, swelling, reduced range of motion, creaking sound (crepitus)
Risk Factors: Age, obesity, previous injury

b) Post-Traumatic Arthritis

Cause: Develops after an injury to the knee, such as fractures or ligament tears
Symptoms: Similar to OA; may develop years after the injury

2. Inflammatory Diseases

These involve inflammation of the knee joint.

a) Rheumatoid Arthritis (RA)

Cause: Autoimmune disease attacking the joint lining
Symptoms: Swelling, pain, warmth, stiffness (especially in the morning); often affects both knees symmetrically

b) Gout

Cause: Uric acid crystal deposition in the joint
Symptoms: Sudden severe pain, redness, swelling, usually in one knee at a time

3. Traumatic / Acute Injuries

Injuries can involve bones, ligaments, tendons, or cartilage.

a) Ligament Injuries (ACL, PCL, MCL, LCL Tears)

Symptoms: Instability, pain, swelling, “popping” sound at injury

b) Meniscus Tears

Cause: Twisting injury or degeneration
Symptoms: Pain, swelling, locking, or catching sensation in the knee

c) Fractures

Cause: Direct trauma
Symptoms: Severe pain, inability to bear weight, swelling, deformity

4. Infectious Diseases

a) Septic Arthritis

Cause: Bacterial infection in the joint
Symptoms: Sudden pain, swelling, redness, fever, inability to move the joint
Emergency: Requires prompt treatment to prevent joint damage

5. Soft Tissue Disorders

a) Bursitis

Cause: Inflammation of the bursa (fluid‑filled sac) in the knee
Symptoms: Swelling, tenderness, sometimes warmth over the joint

b) Tendinitis (Patellar or Quadriceps Tendinitis)

Cause: Overuse, repetitive stress
Symptoms: Pain at tendon attachment, swelling, aggravated by activity

c) Iliotibial Band Syndrome

Cause: Overuse, especially in runners
Symptoms: Pain on the outer side of the knee

6. Congenital or Structural Problems

a) Patellofemoral Pain Syndrome (“Runner’s Knee”)

Cause: Misalignment of patella, overuse
Symptoms: Pain around or behind the kneecap, worse with climbing stairs or sitting

b) Knee Dislocation or Subluxation

Cause: Trauma or ligament laxity
Symptoms: Deformity, pain, swelling, instability

General Symptoms of Knee Disease

Pain or tenderness
Swelling or inflammation
Stiffness or reduced range of motion
Locking, clicking, or popping sounds
Instability or “giving way”
Redness or warmth (in inflammatory or infectious conditions)

Management

Conservative: Rest, ice, compression, elevation (RICE), physiotherapy, anti‑inflammatory medications, lifestyle modification (weight management, exercise).

Degenerative disease