Chondromalacia: AI-Powered MRI Analysis

What your report says: chondromalacia patellae grade 1 to 4

Chondromalacia patellae means the cartilage on the back of the kneecap is softened or damaged. Reports grade it from 1 to 4: grade 1 is softening or swelling, grades 2 and 3 are fissures or defects of increasing size or depth, and grade 4 means the cartilage has worn through to the bone underneath.

Report wording you may see

• “Grade 2 chondromalacia patellae at the median ridge”
• “Chondral fissuring of the lateral patellar facet”
• “Patellar chondrosis” or “high-grade patellofemoral chondral loss”
• “Full-thickness cartilage defect with subchondral edema”

How the grading works

• The original Outerbridge scale was described at surgery. It separates grades 2 and 3 by the size of the damaged area, and grade 4 is erosion down to bone.
• The ICRS scale grades by depth instead: grade 2 involves less than half of the cartilage thickness and grade 3 more than half.
• Cartilage-sensitive MRI sequences detect most kneecap cartilage lesions; in a cadaver study an optimized sequence found 96% of them.
• Location words point to the spot: the medial and lateral facets and the median ridge are areas of the kneecap's underside, and the trochlea is the groove it glides in.

When it tends to matter

A grade alone does not decide treatment; your doctor weighs it with your symptoms, kneecap tracking and examination. Deep or full-thickness defects are the findings most often discussed in detail with an orthopaedic specialist.

Questions for your doctor

• Which grading scale does my report use, and is my grade based on depth or area?
• Which part of the kneecap or the trochlea is affected?
• Is the bone under the cartilage involved?
• Which exercises or activity changes make sense for this grade?

Chondromalacia patella refers to softening, fissuring, and erosion of the cartilage on the undersurface of the patella (kneecap). It is a common cause of anterior knee pain, particularly in young adults and athletes. MRI with cartilage-sensitive sequences can evaluate the extent and grade of cartilage damage. AI can help explain Outerbridge grades (I through IV) and the areas of cartilage described in a report. A clinician must confirm the findings and discuss care with you.

Our guide on how to read a knee MRI shows where the kneecap cartilage appears on axial images.