Work

Jumping Dot Sign: A New Radiological Sign Predicting Inferior Clinical Outcome and Higher Cyst Recurrence Following Bone Marrow Stimulation for Cystic Osteochondral Lesions of the Talus

Year: 2025

Type: article

Abstract: Background: Bone marrow stimulation (BMS) is the most commonly performed surgery for osteochondral lesion of the talus (OLT), but there is a risk of poor outcome when cysts recur. The indications of BMS in the presence of cystic OLT remain controversial. Purpose: To investigate whether a new "jumping dot (JD) sign," manifesting as speckle-like areas of elevated signals surrounding the subchondral bone cyst (SBC) on preoperative magnetic resonance imaging (MRI) against the background of bone marrow edema (BME), could be a predictor of clinical outcome and recurrence of SBCs following BMS and to further propose a more precise indication regarding BMS surgery for cystic OLT. Study Design: Cohort study; Level of evidence, 3. Methods: ) who received BMS between November 2016 and January 2021 were retrospectively studied. Visual analog scale for pain and American Orthopaedic Foot & Ankle Society (AOFAS) scores were assessed preoperatively and at follow-up. The normal bone marrow, BME, and SBCs (including size) were quantified, and the JD sign was evaluated on the preoperative MRI. Notably, the maximal vertical diameter of the cyst was rigorously defined as the greatest distance measured from the superior to the inferior margins of the cyst in this study. The MOCART (magnetic resonance observation of cartilage repair tissue) score and the cyst recurrence were evaluated, and multivariate analysis was performed to evaluate the association of the JD sign with outcomes at the final follow-up. Results: = .008). When the maximal vertical diameter of the cyst was >5.4 mm, the JD sign showed excellent effectiveness in predicting the postoperative cyst recurrence (sensitivity, 81.4%; specificity, 68.9%; positive predictive value, 61.34%; and negative predictive value, 86.44%). Conclusion: The JD sign might be significantly associated with inferior clinical outcomes and higher SBC recurrence following BMS for cystic OLT. For those patients with the maximal vertical diameter of the cyst >5.4 mm and with JD signs, BMS may not be an appropriate option.

Source: Orthopaedic Journal of Sports Medicine

DOI: 10.1177/23259671251358377