ICL#12 –Ankle Repair: How to indicate the Appropriate Treatment Diagnosis and Decision-Making for Treatment

Yoshiharu Shimozono, MD NYU Langone Health, NYU Langone Orthopedic Hospital Department of Foot and Ankle

The diagnosis of cartilage injuries of the ankle are often delayed, potentially because of a low index of suspicion after an ankle sprain or fracture, as well as unclear visualization on standard radiographs. In fact, up to 50% of osteochondral lesions of the talus (OLT) are not visualized on standard radiographs alone, in which case the patient history, physical examination, and more advanced imaging modalities become paramount to achieving an accurate and prompt diagnosis.

Presentation of patients with OLT varies and dependes on many factors. The most common symptoms associated with OLTs, including pain, swelling, and stiffness, are quite nonspecific. These symptoms are often exacerbated by weightbearing. Clinicians must maintain a high degree of suspicion for these lesions as initial evaluation will often yield broad differential diagnoses. These include but are not limited to occult fractures, hindfoot coalitions or deformity, syndesmotic injury, lateral ankle instability, peroneal tendonopathy, impingement, and ankle or subtalar arthritis. When there is concern for an OLT, the patient should be questioned about a history of trauma to the ankle. Physical examination may reveal an effusion, tenderness to palpation over the lesion, decreased range of motion, and pain. Radiographic examination with weightbearing anteroposterior, lateral, and mortise ankle views of the ankle should be performed. Advanced imaging with MRI or CT scan is necessary to visualize lesions not seen on radiographs or to further characterize lesions. MRI provides excellent visualization of the articular surface and soft tissues, which is very helpful for characterizing OLTs. However, with its demonstration of edema in the and cartilage, it may overestimate the size of OLTs or make it difficult to assess the true status of the bone and the exact dimensions of the osteochondral lesion. In contrast, CT scans allow for better visualization of the state of the subchondral bone and the dimensions and locations of subchondral cysts. The treatment of an OLT depends on the grade of the lesion, its chronicity, and the associated symptoms. Asymptomatic lesions are generally followed with serial imagings to monitor for progression. Treatment is reserved for lesions that are symptomatic at presentation or become symptomatic. However, OLT often requires surgical treatment. Many operative techniques have been described to treat OLTs. They can be broadly categorized into cartilage repair, cartilage regeneration, and cartilage replacement techniques. Cartilage repair techniques include microfracture and retrograde drilling. Cartilage regeneraion techniques include autologous chondrocyte implantation (ACI), matrix-induced autologous chondrocyte implantation (MACI), autologous matrix-induced chondrogenesis (AMIC), and derived cells transplantation (BMDCT). Replacement techniques includes osteochondral autograft/allograft transfer, and particulated juvenile cartilage allograft transplantation. Typically, repair techniques are utilized for lesions smaller than 10 mm or 100 mm2. Replacement techniques are indicated for patients whose lesions size greater than 10 mm or 100 mm2, patients who had failed previous microfracture surgery, uncontained lesion and large cystic lesion. Regeneration techniques are often employed after unsuccessful microfracture treatment or to treate larger lesions that are considered less amenable to microfracture. ACI and MACI are 2-stage procedure, however AMIC and BMDCT are 1-step procedure. The treatment algorithm for OLT will be demonstrated in this lecture. These techniques should be augmented with biologics, such platelet-rich plasma (PRP) or concentrated bone marrow aspirate (CBMA). As shown, there are a variety of operative techniques available to treat OLT. Research shows promise with many of these techniques in reducing symptoms associated with the lesions. Given the lack of comparative outcomes research in the field, there are no specific criteria to direct orthopedic surgeons to the optimal option, and treatment must be tailored to each individual patient. More research is necessary to elucidate which treatment options are superior and for which types of patients and lesions they should be directed. Detailed information of operative treatment will be presented in the following lectures.