What is the osteochondral lesion of the talus (OLTs)?

The OLT is a condition related to local damage to the cartilage and adjacent bone at the dome of the talus in the ankle joint. Although some may be related to growth and development, most of the OLTs are related to an acute or repetitive injury. Common examples are athletes with multiple ankle injuries that have persistent pain deep inside the ankle joint. This limited damage to the joint, unfortunately, does not heal naturally as it is interfered with by joint fluid.

What are the imaging studies needed for the diagnosis and treatment of OLTs?

Patients usually have weight-bearing x-rays of the ankle joint as the initial study. X-rays may not detect every small cartilage lesion but are good basic investigations to evaluate bone spurs, loose bodies, and arthritis. MRI or CT scans are the gold standards to visualize the size, shape, and location of the OLTs.

What are the treatments of OLTs?

Some OLTs such as those acute injuries in adolescents can heal using conservative methods such as casting. Recent studies have demonstrated the use of artificial joint fluid to control symptoms related to OLTs. Most of the effective treatments are surgical, ranging from minimally invasive methods to large reconstructive surgeries.

Treatment options are listed below.

1. Arthroscopic debridement and marrow stimulation

2. Arthroscopic debridement with biologic adjuvants (PRP, Bone marrow aspirate, Cartilage graft, ACI, AMIC, MACI, etc.)

3. Osteochondral autograft transplantation

4. Osteochondral allograft transplantation

What are the benefits of minimally invasive treatments for OLT?

Minimally invasive treatments for OLTs are listed in #1 and #2 above. They require only arthroscopic portals or mini-incision without the need for large exposure or taking down of the normal ankle bones. Damaged cartilage and bone are meticulously removed using arthroscopic tools. Cartilage repair is stimulated by creating small holes in the bone at the base of the cartilage lesion. Associated conditions such as bone spurs and loose bodies can be treated at the same time.

Biologic treatments can be added to the arthroscopic procedures if indicated in the same setting.

What is the postoperative care after minimally invasive treatments for OLT?

Patients can usually do full weight-bearing in a boot right away. Ankle motion is encouraged to prevent scar formation. Crutches can be used to assist with walking and fall prevention.

What can I do if arthroscopic surgery didn’t work?

When the cartilage damage is larger than 1-1.5 cm, the risk of failure from arthroscopic procedures increases. In addition, arthroscopic procedures require a steep learning curve and an incomplete treatment from previous surgery is possible. If the lesion is limited in size, a revision arthroscopic treatment is recommended with or without biologic adjuvants. If the lesion is larger than 1.5-2 cm, the patient may benefit from osteochondral autograft transplantation with the donor site at the ipsilateral knee. If the lesion is larger than 2.5 cm, the use of allograft is indicated.

Author: Phinit Phisitkul, MD