Learning Curve of Third-generation Minimally Invasive Chevron-Akin Osteotomy for Hallux Valgus Correction in Asian Population: A Retrospective Cohort Study
Ramesh Radhakrishnan, Adriel YW Tay, Kae Sian Tay, Nicholas EM Yeo
Citation Information :
Radhakrishnan R, Tay AY, Tay KS, Yeo NE. Learning Curve of Third-generation Minimally Invasive Chevron-Akin Osteotomy for Hallux Valgus Correction in Asian Population: A Retrospective Cohort Study. J Foot Ankle Surg Asia-Pacific 2025; 12 (2):77-83.
Background: Minimally invasive Chevron-Akin (MICA) osteotomy has gained popularity for hallux valgus (HV) correction due to its soft tissue preservation and early weight-bearing benefits. However, the learning curve for mastering this technique, particularly in an Asian population, remains unclear.
Objective: This study aims to evaluate the learning curve of third-generation MICA osteotomy for HV correction in an Asian population and to determine the number of cases required to achieve surgical expertise.
Methods: A retrospective cohort study was conducted on 49 patients who underwent MICA by a single surgeon at a tertiary institution between January 2018 and April 2020. Patients were stratified into sequential groups based on the surgeon's experience. Variables studied include perioperative parameters such as operative time, duration of exposure to image intensifier, length of hospital stay, incidence of complications, and radiologic and clinical outcomes.
Results: The learning curve demonstrated a statistically significant reduction (21%) in operative time after approximately 24 cases (95% CI, 10–37), indicating the threshold for achieving proficiency. A significant reduction in postoperative complications, including persistent metatarsal head or screw prominence, was observed in the late group (n = 1) compared to the early group (n = 6) (p = 0.049). Significant improvements in hallux valgus angle (HVA) and intermetatarsal angle (IMA) were observed postoperatively across all groups, with no significant differences in final clinical outcomes between early and late cohorts.
Conclusion: The learning curve for third-generation MICA osteotomy is well-defined, with surgical proficiency attained after approximately 24 cases. As surgeons gain experience with an adequate number of cases, patients have been shown to benefit from lower complication rates and greater postoperative pain relief. These insights are crucial for optimizing surgical training and integrating MICA into clinical practice.
Level of evidence: Level III, retrospective cohort study.
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