What are the implications of hypertrophic changes in the patellofemoral compartment on a knee X-ray (X-ray)

From the Guidelines

Patellofemoral compartment hypertrophic change on knee X-ray indicates early osteoarthritis affecting the joint between the kneecap (patella) and thigh bone (femur), and initial management should focus on conservative measures including knee-targeted exercise therapy, education, and supportive interventions as required, as recommended by the most recent and highest quality study 1. The goal of treatment is to reduce pain, improve function, and slow disease progression.

• Key components of conservative management include:
  • Knee-targeted exercise therapy to strengthen quadriceps and hamstring muscles, improving patellar tracking and reducing pressure on the joint 1
  • Education to challenge inaccurate beliefs, build confidence and understanding of the diagnosis, and promote autonomy and reduce fear 1
  • Supportive interventions such as prefabricated foot orthoses, movement/running retraining, and taping, as needed and based on individual patient factors 1
• Additional measures that may be considered include:
  • Weight loss if overweight
  • Low-impact exercises like swimming or cycling
  • Over-the-counter pain medications such as acetaminophen or NSAIDs like ibuprofen
  • Ice applied for 15-20 minutes several times daily to reduce inflammation
• If conservative measures fail after 4-6 weeks, further evaluation with MRI and referral to an orthopedic specialist may be warranted to consider more advanced interventions, as suggested by the best practice guide for patellofemoral pain 1. The most recent and highest quality study 1 provides a clinical framework for the application of evidence into practice when treating people with patellofemoral pain, and highlights key evidence gaps to be addressed by future high-quality research. Overall, a comprehensive and individualized approach to management, incorporating the latest evidence and expert clinical reasoning, is essential to optimize outcomes for patients with patellofemoral compartment hypertrophic change on knee X-ray 1.

From the Research

Implications of Hypertrophic Changes in the Patellofemoral Compartment on a Knee X-ray

• Hypertrophic changes in the patellofemoral compartment on a knee X-ray may indicate patellofemoral arthrosis, a common cause of knee pain in middle-aged patients 2
• Patellofemoral arthrosis is often associated with patellofemoral malalignment, and a correct diagnosis is established by history taking and physical and radiographic examinations of the knee 2
• The initial treatment of choice for patellofemoral arthrosis is conservative treatment, which includes anti-inflammatory drugs, use of a knee brace, quadriceps-strengthening exercises, physical therapy, and modification of activity 2
• Surgery is indicated when patients fail to improve after at least 6 months of conservative treatment and are functionally disabled, with options including lateral retinacular release, proximal realignment, and distal realignment by anteromedial transfer of the tibial tubercle 2

Diagnostic and Treatment Options

• Patellofemoral pain is a frequent and often challenging clinical problem, and diagnosis of the specific cause of pain can be difficult, requiring assessment of lower extremity strength, alignment, and range of motion, as well as specific patella alignment, tracking, and mobility 3
• The treatment for patellofemoral pain is usually conservative with anti-inflammatory medications, activity modification, and a specific physical therapy program focusing on strengthening and flexibility 3
• Infrequently, surgical treatment may be indicated after a non-operative program fails, with outcomes of surgical management including debridement, lateral release, and realignment of the extensor mechanism to unload the patellofemoral articulation being favorable 3
• Recent research suggests that patellofemoral pain pathophysiology is a combination of biomechanical, behavioral, and psychological factors, and targeted exercise therapy and other conservative therapy modalities have shown efficacy, especially when used in combination 4

Physical Examination and Patellofemoral Pain Syndrome

• Patellofemoral pain syndrome is multifactorial in origin, and a combination of variables, including abnormal lower limb biomechanics, soft-tissue tightness, muscle weakness, and excessive exercise, may result in increased cartilage and subchondral bone stress, patellofemoral pain, and subtle or more overt patellar maltracking 5
• An extensive search of the literature revealed no single gold-standard test maneuver for patellofemoral pain syndrome, and the reliability of the maneuvers described was generally low or untested 5
• An abnormal Q-angle, generalized ligamentous laxity, hypomobile or hypermobile tenderness of the lateral patellar retinaculum, patellar tilt or mediolateral displacement, decreased flexibility of the iliotibial band and quadriceps, and quadriceps, hip abductor, and external rotator weakness were most often correlated with patellofemoral pain syndrome 5