Ankle
Osteochondral Lesion of the Talus
About Your Condition
The talus is the ankle bone that forms the lower surface of the ankle joint. Its upper surface is covered with a smooth layer of cartilage that allows painless, frictionless movement. An osteochondral lesion (OLT) is an area of damage to this cartilage and the underlying bone — typically caused by an ankle sprain or injury, though sometimes arising without a clear precipitating event. Lateral ankle sprains are the most common cause, and chronic instability can cause repeated micro-trauma to the same area.
The result is a localised area of softened, detached, or absent cartilage, causing pain within the ankle joint during weight-bearing, occasional swelling, catching, or a feeling of instability. An OLT is a focal cartilage defect rather than diffuse arthritis, though if left untreated a significant lesion can eventually lead to generalised ankle arthritis.
Non-Operative Management
Management depends on whether the lesion is a recent, acute injury or a longer-standing chronic issue.
Acute Presentation
- Relative rest and reducing impact activity allows inflammation within the lesion to settle and gives the bone an opportunity to stabilise. Low-impact alternatives such as swimming or cycling let you maintain fitness while keeping load off the ankle.
- A period in a walking boot (moon boot) may be recommended to offload the ankle and reduce mechanical stress on the damaged area. Smaller lesions in younger patients can show partial healing with this protected activity, though larger or symptomatic lesions — particularly those with detached fragments — are less likely to resolve without surgical intervention.
Chronic Symptomatic
- A rocker-soled shoe reduces ankle joint motion and load through the lesion during walking.
- Strengthening of the peroneal and other secondary stabilising muscles of the ankle improves dynamic stability and reduces load through the lesion.
- Proprioception training is particularly important if the lesion arose in the context of ankle instability.
- If chronic ankle instability contributed to the lesion, addressing the instability through physiotherapy or ligament reconstruction is an important part of management.
When to Consider Surgery
Surgery is considered when symptoms significantly limit your daily activities despite an adequate trial of non-operative treatment, or when the lesion is large, a fragment is detached, or the quality of overlying cartilage is poor on imaging. Lesion size is one of the most important factors in deciding between surgical approaches and predicting outcomes.
Two surgical approaches are used depending on lesion size: Arthroscopic debridement and microfracture, a minor procedure for smaller lesions, and OATS (Osteochondral Autograft Transfer), a more major procedure for larger or previously treated lesions.