What is the recommended treatment for a chondral/subchondral irregularity on the inferior aspect of the right patella?

Management of Chondral/Subchondral Irregularity of the Inferior Patella

The recommended first-line treatment for chondral/subchondral irregularity of the inferior patella is conservative management including physical therapy focused on quadriceps strengthening, activity modification, and anti-inflammatory medications, progressing to surgical intervention only if conservative measures fail. 1

Conservative Management Approach

Initial Treatment (First 6-8 weeks)

• Activity Modification:

  • Reduce high-impact activities
  • Avoid deep knee bending and prolonged sitting
  • Consider temporary use of assistive devices if pain is severe 1

• Physical Therapy:

  • Quadriceps strengthening exercises
  • Hamstring stretching
  • Core strengthening
  • Proprioceptive training
  • Patellar mobilization techniques 1
  • Eccentric exercise to reduce symptoms, increase strength, and promote healing 2

• Pain Management:

  • NSAIDs for pain and inflammation
  • Topical analgesics
  • Ice application after activity (15-20 minutes, 2-3 times daily) 1
  • Deep transverse friction massage to reduce pain 2

Assessment of Treatment Response

After 8 weeks of conservative management, patients typically can be categorized as responders or non-responders. Research shows that patients with higher subchondral bone metabolism in the patella (as indicated by SPECT-CT imaging) are more likely to be non-responders to conservative therapy, with a positive predictive value of 62-67% for non-response in patients with higher patella uptake 3.

Surgical Management (For Non-Responders)

If conservative management fails after 8 weeks, surgical options should be considered based on lesion size:

• For lesions <2 cm²:

  • Chondroplasty/debridement of unstable cartilage flaps 1, 4
  • Microfracture for contained lesions <4 cm² 1

• For lesions >2 cm²:

  • Osteochondral autologous transfer (OAT) - particularly effective for young patients (<40 years) with high-grade patellar defects 5
  • Advanced cartilage restoration techniques such as autologous chondrocyte implantation (ACI) or matrix-assisted ACI (MACI) 1

Rehabilitation After Surgical Intervention

• Early phase (0-6 weeks):

  • Protected weight-bearing
  • Range of motion exercises
  • Quadriceps activation 1

• Intermediate phase (6-12 weeks):

  • Progressive strengthening
  • Functional exercises
  • Gradual return to activities 1

• Advanced phase (3-6 months):

  • Sport-specific training
  • Return to full activities based on functional testing 1

Clinical Pearls and Pitfalls

• Important caveat: Most patellofemoral chondral defects associated with instability are less than 2 cm² and generally do not require intervention beyond chondroplasty 4.

• Common pitfall: Failing to address underlying patellar instability when present. Any treatment strategy for chondral defects of the patellofemoral joint should first address causes of recurrent instability 4.

• Treatment outcomes: Studies show good results with OAT for patellar chondral defects, with mean Kujala scores of 90.42 and WOMAC scores of 95 at midterm follow-up 5.

• Diagnostic consideration: For persistent cases, SPECT-CT imaging can help predict response to conservative management and correlates well with arthroscopic assessment of patellar chondral lesions 3.