What is the diagnosis and treatment for a patient with pain in the right knee when climbing stairs and running, tenderness in the inferolateral patella region, and a normal Magnetic Resonance Imaging (MRI) scan?

Patellofemoral Pain Syndrome (PFPS)

This is patellofemoral pain syndrome, and treatment should begin immediately with knee-targeted exercise therapy combined with hip strengthening exercises, patient education about the benign nature of the condition, and consideration of prefabricated foot orthoses—surgery is not indicated. 1

Diagnosis

The clinical presentation of inferolateral patellar tenderness with pain during stair climbing and running in a patient with normal MRI is diagnostic of PFPS. 2 This is the most common cause of knee pain in the outpatient setting, accounting for 11-17% of all knee pain presentations in primary care. 2

Key Diagnostic Features Supporting PFPS:

• Pain location and pattern: Retropatellar or peripatellar pain that worsens with activities requiring knee flexion under load (stairs, running, squatting, prolonged sitting with flexed knees) is pathognomonic for PFPS. 1, 2
• Normal MRI: The absence of structural abnormalities on MRI effectively rules out meniscal tears, ligamentous injuries, osteochondral lesions, and significant cartilage pathology. 3
• Age consideration: In patients aged 45-55 years with normal radiographs, elevated T2 mapping values on 3T MRI may indicate early cartilage changes, but this still presents clinically as PFPS and is managed identically. 4, 2

Differential Considerations Already Excluded by Normal MRI:

The normal MRI has effectively ruled out patellar tendinopathy, fat pad impingement syndromes, Hoffa's disease, deep infrapatellar bursitis, iliotibial band syndrome, adhesive capsulitis, medial plicae, discoid meniscus, tumors, ganglion cysts, pigmented villonodular synovitis, and osteonecrosis. 3

Treatment Protocol

First-Line Treatment (Initiate Immediately):

Exercise Therapy Foundation 1:

• Knee-targeted exercises: Progressive resistance straight leg raises, terminal knee extension exercises, and quadriceps strengthening in pain-free ranges
• Hip strengthening: Hip abductor exercises including side-lying leg raises and clamshells, as hip weakness is a common contributing factor 1
• Stretching program: Iliotibial band stretching, hamstring stretching, and gastrocnemius stretching performed twice daily until symptoms resolve, then three times weekly for maintenance 5
• Frequency: Exercises should be performed twice daily during the acute phase 5

Patient Education 1:

• Explain that pain does not correlate with tissue damage—the normal MRI confirms no structural injury
• Clarify that PFPS is caused by imbalances in forces controlling patellar tracking, not progressive joint destruction 6
• Set realistic expectations: 60-80% of patients respond favorably to conservative treatment, but persistence with exercise is critical 5
• Address that over 50% of patients report persistent pain beyond 5 years when they fail to persist with exercise therapy or over-rely on passive treatments 1

Adjunctive Treatments (Add Based on Symptom Severity):

Prefabricated Foot Orthoses 1:

• Prescribe when patients respond favorably to treatment direction tests
• Most beneficial in the short term
• Should be customized for comfort

Patellar Taping 1:

• Use as an adjunct to facilitate exercise therapy
• Particularly helpful when rehabilitation is hindered by high symptom severity, irritability, or fear of movement

Manual Therapy 1:

• Soft tissue mobilization of lateral retinacular structures and iliotibial band 1
• Use to facilitate exercise delivery, not as standalone treatment

What NOT to Do:

NSAIDs: There is little evidence to support routine use of nonsteroidal anti-inflammatory drugs for PFPS. 6

Knee Braces: There is little evidence to support routine use of knee braces. 6

Surgery: Should be considered only after failure of a comprehensive rehabilitation program, which is rarely indicated for PFPS. 6 The normal MRI confirms there is no structural pathology requiring surgical intervention.

Reassessment Timeline

If no improvement after 6-8 weeks of consistent therapy 1:

• Reassess the diagnosis
• Consider radiographs if not already obtained (to rule out osteoarthritis, osteophytes, loose bodies) 2
• Evaluate hip and lumbar spine clinically, as hip pathology commonly refers pain to the knee 2
• Assess for knee effusion, as presence guides treatment approach 2

Common Pitfalls to Avoid

Focusing only on knee exercises without addressing hip strength is a frequent error that leads to treatment failure. 1

Over-reliance on passive treatments (taping, manual therapy, orthoses) without emphasizing active exercise therapy leads to poor long-term outcomes. 1

Inadequate patient education about the benign nature of the condition and the importance of exercise persistence contributes to the high rate of chronic symptoms. 1

Ordering excessive imaging: The normal MRI has already provided sufficient information—further imaging is not indicated unless symptoms fail to improve with appropriate conservative management or new symptoms develop. 3, 1