Published online Feb 18, 2022. doi: 10.5312/wjo.v13.i2.178
Peer-review started: July 30, 2021
First decision: November 11, 2021
Revised: November 18, 2021
Accepted: January 6, 2022
Article in press: January 6, 2022
Published online: February 18, 2022
Osteochondral lesions of the Talus (OLT) are pathologic lesions of the talar cartilage and the subchondral bone. These lesions can occur in up to 50% of acute ankle fractures and sprains. For OLTs of larger size (i.e., above 10 or 15 mm in diameter) and of non-fragmentous morphology, the ‘standard’ operative treatment options such as autologous chondrocyte implantation, osteochondral autograft transfer systems, and a Talar OsteoPeriostic grafting from the Iliac Crest procedure may result in satisfactory clinical outcomes. However, in some patients, there are multiple secondary lesions present of large and cystic nature. For these lesions, it is not always possible to harvest an osteo(chondral) autograft that is large enough to replace all the diseased osteochondral tissue of the talus without damaging the donor site or compromising the congruency of the ankle joint. Allograft treatment could be considered for the treatment of these type of lesions. However, these contain the disadvantages of loss of viability and stability in one-third of the grafts, and possibly clinically fail due to immunological reactions. However, when there are multiple secondary (i.e., failed prior surgery) lesions present on the talar articular surface in combination with a large and cystic nature, the above-described operative interventions are to be expected to result in relatively inferior outcomes.
Currently, it is difficult to treat patients with osteochondral lesions of the ankle that are of multiple, cystic and secondary nature. This is because the lesions are considered relatively large and difficult to treat. For this indication, it was usually performed to fuse the ankle joint. However, in the past 2 to 5 years, novel innovative surgical options have been developed, such as the Ankle Spacer, in order to overcome an ankle fusion or ankle prosthesis.
To describe the operative technique and the clinical efficacy of the Ankle Spacer for the treatment of multiple, cystic OLTs in patients with failed prior operative treatment.
In a prospective study including patients with multiple, cystic or large osteochondral lesions of the talus were included who failed previous surgical treatment. We looked at the numeric rating scale (NRS) for pain during walking at 2 years after implantation of the Ankle Spacer and we also assessed the NRS in rest and during stair-climbing, the American Orthopaedic Foot and Ankle Outcome Score, the Foot and Ankle Outcome Score, the Short-Form 36 and the range of motion of the ankles both pre-operatively as well as post-operatively. Radiographic evaluations were conducted to evaluate prosthetic loosening and subsidence. Revision rates and complications were also assessed.
In this prospective study, two patients underwent the implantation of an Ankle Spacer for osteochondral damage on the talar dome. We found that there were clinically relevant pain reductions during walking as well as important improvements in clinical outcomes as assessed with the patient-reported outcome measures. Furthermore, it was found that there were no complications nor re-operations.
The Ankle Spacer showed good clinical outcomes and clinically relevant pain reduction during walking, improvement in clinical outcomes as assessed with PROMs, and no complications or re-operations. This treatment option may therefore evolve as a joint-sparing alternative to an ankle arthrodesis, a total talar implant or a total ankle arthroplasty/resurfacing.
Future research should be focused at the development of a prospective, self-learning algorithm taking into account the individual patient factors influencing outcomes after conservative and surgical treatment so that we can assess which patients would benefit most from which treatment options.