The talus bone, which is the part of the ankle that enables smooth movement, has a dome-shaped top covered in a layer of cartilage. An injury can cause damage to this area and the underlying subchondral bone, resulting in a talar dome injury typically referred to as an osteochondral lesion or defect. While injuries commonly present on the inside or medial aspect of the ankle, the outer ankle can be affected as well.
Causes of Talar Dome Injuries
The cause of a talar dome injury may be due to major traumatic events or repetitive stress injuries such as:
- Direct impact from heel strike
- Severe or recurrent ankle sprains
- Repetitive micro-trauma
Up to 70% of acute injuries like ankle sprains and fractures result in talar dome lesions1 If proper treatment is not received, it may lead to improper healing of the cartilage, an increased risk of deterioration or softening, and further damage to the talus surface over time.
Continuous minor trauma over a prolonged period caused by unaddressed or undetected biomechanical issues can result in injury to the talar dome. These issues include hypermobility or a low-arch foot type (flatfoot), which can eventually lead to osteochondral lesions in both ankles.
Symptoms and Signs of Talar Dome Injury
Symptoms often develop gradually over time and are not immediately perceivable, leading to misdiagnoses in minor cases. These may present as:
- Chronic pain felt deep within the ankle
- Incidents of unprompted swelling, weakness, and locking of the ankle joint
- Formation of subchondral cysts
Symptoms may worsen as the condition progresses and can lead to lifestyle restrictions or impact daily activities for those who are physically active. Insufficient or lack of treatment commonly results in osteoarthritis, changes of the ankle joint, recurrent and chronic pain linked to secondary nerve pain, and limitations in joint range of motion. As such, we recommend that proper treatment is sought promptly to prevent the onset of further debilitating symptoms.
X-rays or an MRI of the ankle are performed to diagnose and determine the size, extent, and stability of the talar dome lesion or injury. The application of non-invasive talar dome lesion treatments depends on several factors:
- Lesion size, extent, and stability
- Activity levels of patient
- Underlying biomechanical variances
Following treatment therapies, patients will benefit from the use of offloading devices such as customised ankle foot orthotics (AFOs). In addition to deterring the recurrence of the prior injury, AFOs offer stabilisation by preventing over-rotation of the injured ankle. Your podiatrist will conduct subsequent follow-up sessions to ensure the injury is healing and that any insecurities have been addressed.
Surgical intervention may be considered if non-invasive methods are ineffective at relieving pain and other related symptoms, or if the lesion is too severe and is unable to be treated. Consult your podiatrist for more information, or to make sure that you are a suitable patient for this procedure.