Analysis of the Changes in the Clinical Outcomes According to Time After Arthroscopic Microfracture of Osteochondral Lesions of the Talus

Background: Arthroscopic microfracture can effectively treat osteochondral lesions of the talus (OLTs). However, very few studies have reported on symptomatic improvement duration and time when symptomatic improvement ceases. This study aimed to investigate the clinical outcome changes after arthroscopic microfracture in patients with OLT. Methods: Among patients who underwent arthroscopic microfracture for OLT, 70 patients were available for follow-up for more than 3 years. Of these, 6 patients who showed worsening or no improvement in the 6 months after surgery were excluded, and a total of 64 patients were included in the analysis. To analyze and compare the clinical outcome changes according to time, the visual analog scale (VAS) and American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot scores were evaluated every 3 months up to 1 year postoperatively and every 1 year thereafter. The clinical outcome differences based on the lesion size, lesion location, lesion containment, presence of cyst and bone marrow edema, age, sex, and obesity were analyzed. Results: The preoperative and final follow-up VAS scores significantly improved from 6.2 ± 1.1 to 1.2 ± 1.1 (P <.05) and the AOFAS score from 63.1 ± 7.3 to 91.0 ± 7.3 (P <.05). The overall success rate for arthroscopic microfracture in this study was 88.6%. The postoperative VAS and AOFAS scores at 3, 6, 9, 12, 24, and 36 months were 3.7 ± 1.4, 2.5 ± 1.3, 2.0 ± 1.1, 1.6 ± 1.2, 1.2 ± 1.2, and 1.3 ± 1.2 and 74.7 ± 10.3, 80.5 ± 8.9, 84.3 ± 7.4, 88.3 ± 7.3, 91.1 ± 7.2, and 90.8 ± 7.5, respectively, showing significant improvements up to 2 years. After 2 years, the symptoms did not improve but were maintained at a certain level up to 3 years. No clinical outcome differences based on the lesion size, lesion containment, presence of cyst and bone marrow edema, age, sex, and obesity were observed. Conclusion: Symptomatic improvement early after arthroscopic microfracture for OLT was observed continuously for up to 2 years postoperatively. Symptom improvement was maintained without worsening for up to 3 years after surgery. Determining the final outcome of microfracture at least after 2 years would be reasonable. Level of Evidence: Level IV, case series.