What is the recommended management for a patient presenting with an osteochondral ankle lesion?

Management of Osteochondral Ankle Lesions

MRI without IV contrast is the reference standard for evaluating osteochondral ankle lesions and should be obtained within 2-3 weeks when radiographs demonstrate or suggest this injury, as it has 96% sensitivity for detection and 97% sensitivity for determining lesion stability—critical factors that guide treatment decisions. 1, 2, 3

Initial Diagnostic Approach

Imaging sequence:

• Plain radiographs are the first-line study but miss 41% of osteochondral abnormalities, detecting only 59% of lesions overall 1, 2, 3
• MRI without contrast should follow when radiographs show fracture, potential osteochondral injury, or when clinical suspicion remains high despite negative radiographs 1, 2
• CT can serve as an alternative if MRI is contraindicated, offering 99% specificity but lower sensitivity than MRI 1, 2

Key MRI findings that determine management:

• High signal line deep to the lesion on T2-weighted images indicates instability and typically requires surgical intervention 1, 3
• Subchondral bone edema represents active pathology causing symptoms 3
• Lesion size, containment status, and presence of adjacent cysts guide specific treatment selection 1, 3

Treatment Algorithm Based on Lesion Characteristics

For small, contained lesions (<100 mm² or <10 mm):

• Conservative management initially: rest, NSAIDs, activity modification for 2-3 weeks 4, 5
• If symptoms persist, arthroscopic debridement with microfracture or drilling is indicated 4, 5
• Younger patients (<30 years) have significantly better outcomes with arthroscopic drilling—12 of 13 patients in this age group achieved good results versus only 1 of 5 patients ≥50 years 6

For large lesions (>100 mm² or >10 mm), cystic lesions, or uncontained lesions:

• Osteochondral autograft transplantation (OATS) or allograft transplantation is indicated 2, 5
• These lesions typically fail conservative management and bone marrow stimulation techniques 5

For lesions with evidence of instability on MRI:

• Surgical intervention is warranted regardless of size 3
• Combined open approach and arthroscopy may be needed for specific lesion types like LIFT lesions (lateral inverted fracture of talus) 1

Critical Management Principles

Early intervention is essential, particularly in younger patients (≤50 years):

• The American Academy of Orthopaedic Surgeons emphasizes joint-preserving strategies because osteochondral defects have limited healing capacity and progress to disabling arthritis if untreated 2, 3
• Shorter interval between injury and surgery correlates with better radiographic outcomes—mean 6.3 months for good results versus 11.3 months for fair results 6

Timing considerations:

• Do not delay specialist referral if symptoms persist beyond 2-3 weeks of conservative management 3
• In trauma cases with confirmed osteochondral injury, obtain MRI within 2-3 weeks to assess full extent and plan definitive treatment 2

Common Pitfalls to Avoid

• Never dismiss persistent symptoms as merely "degenerative"—osteochondral lesions can progress to articular collapse with significantly increased morbidity 3
• Do not rely solely on radiographs—they miss nearly half of osteochondral abnormalities 1, 2
• Avoid ordering MRI with contrast—it provides no additional diagnostic information for osteochondral lesions and is not routinely recommended 3
• Do not assume all lesions can be managed conservatively—more than one-third of cases fail conservative treatment and require surgery 4

Surgical Approach Selection

CT has specific utility for surgical planning:

• Identifies cortical and subcortical involvement, intra-articular ossific bodies, and associated fractures 1
• Uncontained lesions with "shoulder" configuration have more complicated clinical outcomes, making precise localization critical 1
• Particularly important for complex anatomy like subtalar, calcaneal, and talar fractures 1

The choice between arthroscopic versus open procedures depends on:

• Lesion accessibility (medial lesions may not require malleolar osteotomy with arthroscopic drilling) 6
• Lesion size and containment status 5
• Presence of cartilage surface disruption versus intact overlying cartilage 6