An osteochondral lesion of the talus (OLT) is a lesion involving the talar articular cartilage
and its subchondral bone. OLT is a known cause of chronic ankle pain after ankle sprains
in the active population. The lesion causes deep ankle pain associated with weight-bearing,
impaired function, limited range of motion, stiffness, catching, locking, and swelling. There
are 2 common patterns of OLTs. Anterolateral talar dome lesions result from inversion and
dorsiflexion injuries of the ankle at the area impacting against the fibula. Posteromedial lesions
result from inversion, plantar flexion, and external rotation injuries of the ankle at the area
impacting against the tibial ceiling of the ankle joint. Early diagnosis of an OLT is particularly
important because the tibiotalar joint is exposed to more compressive load per unit area than
any other joint in the body. Failure of diagnosis can lead to the evolution of a small, stable lesion
into a larger lesion or an unstable fragment, which can result in chronic pain, joint instability,
and premature osteoarthritis.
A 43-year-old man, with a history of ankle sprain one year previously, visited our pain clinic
for continuous right ankle pain after walking or standing for more than 30 minutes. There
was a focal tenderness on the posteromedial area of the right talus. Imaging studies revealed
a posteromedial OLT classified as having a geode form according to the FOG (fractures,
osteonecroses, geodes) radiological classification and categorized as a stage 2a lesion on
magnetic resonance imaging.
The patient was scheduled for aspiration and osteoplasty with hydroxyapatite under arthroscopic
and fluoroscopic guidance. A 26-gauge needle was inserted to infiltrate local anesthetics into
the skin over the cyst and ankle joint. An arthroscope was placed into the joint to approach the
OLT. The arthroscopic view showed that there was no connection between the OLT and the cyst
of the talus body. A 13-gauge bone biopsy needle was inserted into the cyst, and aspiration was
performed. Aspirated fluid from the cyst was originally white and clear; however, it changed to
a blood-tinged, reddish color due to mixing with the incisional blood. After aspiration, contrast
medium was injected, and the shape of the spread was observed. Bone cement comprising
hydroxyapatite was injected to fill the bone defect of the cyst. A 1.5 mL volume of cement was
injected into the talus under vigilant fluoroscopic and arthroscopic monitoring to prevent its
dissemination into the joint. There was no cement leakage into the vessels or articular space.
Postoperative fluoroscopy and computed tomography images showed bone cement filling of
the defect.
In the present case, arthroscopic and fluoroscopic guidance was used for aspiration of an OLT
and for performing percutaneous osteoplasty with hydroxyapatite for one defect; this treatment
decreased pain upon weight bearing and enabled a return to work without any restrictions one
week after the procedure. The purpose of this report was to highlight the presence of OLT in
chronic ankle pain and to review its management strategies.
Key words: Ankle, bone fracture, cartilage fracture, calcium polyacrylate-hydroxyapatite
cement, cementoplasty, endoscopy, osteochondritis dissecans, pain, sprain, talus.