Signs and Symptoms
Evaluation of knee pain should begin with general questions regarding duration and rapidity of symptom onset and the mechanism of injury or aggravating symptoms. Overuse or degenerative problems can occur with stress or compression from sports, hobbies, or occupation.
A history of trauma, previous orthopedic problems with, or surgery to, the affected knee should also be specifically queried. Symptoms of infection (fever, recent bacterial infections, risk factors for sexually transmitted infections [such as gonorrhea] or other bacterial infections [such as staphylococcal infection]) should always be elicited.
Common symptom complaints include the following:
1. Presence of grinding, clicking, or popping with bending, may be indicative of osteoarthritis or the patella femoral syndrome.
2. “Locking” or “catching” when walking suggests an internal derangement, such as meniscal injury or a loose body in the knee.
3. Intra-articular swelling of the knee or an effusion indicates an internal derangement or a synovial pathology. Large swelling may cause a popliteal (Baker) cyst. Acute swelling within minutes to hours suggests a hemarthrosis, most likely due to an ACL injury, fracture or patellar dislocation, especially if trauma is involved.
4. Lateral “snapping” with flexion and extension of the knee may indicate inflammation of the iliotibial band.
5. Pain that is worsened with bending and walking downstairs suggests issues with the patellofemoral joint, usually degenerative such as chondromalacia of the patella or osteoarthritis.
6. Pain that occurs when rising after prolonged sitting suggests a problem with tracking of the patella.
Location of common causes of knee pain.
Medial knee pain
• Medial compartment osteoarthritis
• Medial collateral ligament strain
• Medial meniscal injury
• Anserine bursitis (pain over the proximal medial tibial plateau)
Anterior knee pain
• Patellofemoral syndrome (often bilateral)
• Prepatellar bursitis (associated with swelling anterior to the patella)
• “Jumper’s knee” (pain at the inferior pole of the patella)
• Septic arthritis
• Gout or other inflammatory disorder
Lateral knee pain
• Lateral meniscal injury
• Iliotibial band syndrome (pain superficially along the distal
• iliotibial band near lateral femoral condyle or lateral tibial insertion)
• Lateral collateral ligament sprain (rare)
Posterior knee pain
• Popliteal (Baker) cyst
• Meniscal tears
• Hamstring or calf tendinopathy