Spontaneous Radiographic Improvement of a Large Cystic Osteochondral Lesion of the Talar Shoulder Following Realignment Surgery for Symptomatic Improvement
Authors: Kim Jaeyoung , Yi Young , Lee Woo-Chun 
Published: December 2023

Category:

Sports; Ankle

Introduction/Purpose:

Treating patients with a large cystic osteochondral lesion of the talar shoulder and concurrent radiographic evidence of foot and ankle malalignment is a clinical challenge. Differentiating the origin of pain in such a situation is not always straightforward, and surgical treatment for both conditions at the same time can complicate the surgery. It has been suggested that unaddressed malalignment can lead to an unfavorable result after osteochondral lesion of the talus (OLT) surgery, but the isolated effect of realignment surgery on OLT patients has not been elucidated. Therefore, the purpose of this study was to evaluate the outcomes of realignment surgery for symptomatic relief in patients with a large cystic OLT of the talar shoulder with concurrent malalignment of the foot and ankle.

Methods:

This retrospective study reviewed 27 patients (mean age: 34.4 years) with large cystic OLTs (>10mm in diameter) of the talar shoulder who underwent realignment surgery. Patients were excluded if they had plain radiographs suggestive of degenerative ankle arthritis, or less than 2 years of follow-up. Patients' symptoms prior to surgery were categorized by location and character. The types of realignment procedure were determined by a senior surgeon based on the patients' symptoms and radiographic findings from plain x-rays and weightbearing computed tomography. None of the included patients underwent any type of cartilage repair or replacement procedures during the realignment surgery. Clinical improvement was assessed using the foot function index (FFI) and visual analogue scale (VAS). The location of the OLTs was categorized into 9-Raikin zones, and the size of the OLTs was measured and compared pre- and postoperatively using previously described methods.

Results:

There were 25 patients with a medial lesion (zone 4 [n=19]; zone 7 [n=5]; zone 1 [n=1]) and two with a lateral lesion (zone 6). Despite the location of the OLT, patients' symptoms varied, with 13 experiencing diffuse medial and lateral pain, 13 experiencing lateral pain, and 1 experiencing anteromedial pain as their primary location of pain. Supramalleolar osteotomy (SMO) was performed in 18 patients (medial open-wedge [n=17] and dome-type [n=1]), while hindfoot correction without SMO was done in 9 patients. Postoperatively, both the FFI and VAS scores significantly improved. The mean preoperative size of cystic lesion was 32.9mm3 (range, 12.6-79.6), and there was a significant decrease in size to 16.3mm3 (range, 0-40.1) postoperatively. During the follow-up period, no subsequent surgery for OLT was necessary.

Conclusion:

We found that the main location of pain does not always match with the location of OLT in this selected cohort. Our study results suggest that realignment procedures can improve symptoms and contribute to a decrease in size of the osteochondral lesion in patients who demonstrate a large cystic OLT of the talar shoulder and malalignment of the foot and ankle at the same time. Addressing malalignment primarily in such patients can potentially minimize the risk of morbidities or complications associated with procedures involving replacement surgery for the large cystic OLTs of the talar shoulder.