Browsing by Author "Lam, Peter"

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    A Novel Simulation Model and Training Program for Minimally Invasive Surgery of Hallux Valgus
    (Lippincott Williams & Wilkins, 2024) Morales Díaz, Sergio Luis; Lam, Peter; Cerrato, Rebecca; Mococain, Pablo; Ruz Laurent, Cristian Andrés; Filippi Nussbaum, Jorge Luis; Villa Massiff, Andrés Alberto; Varas Cohen, Julian Emanuel
    Background: Minimally invasive surgery (MIS) for hallux valgus (HV) has gained popularity. However, adopting this technique faces the challenges of a pronounced learning curve. This study aimed to address these challenges by developing and validating an innovative simulation model and training program, targeting enhanced proficiency in HV MIS.Methods:A training program and a high-fidelity simulation model for HV MIS were designed based on experts' recommendations. Four foot and ankle surgeons without experience in MIS formed the novice group and took the program that encompassed six-session instructional lessons, hands-on practice on simulated models, and immediate feedback. The program concluded with a cadaveric surgery. Four foot and ankle experienced MIS surgeons formed the expert group and underwent the same procedure with one simulated model. Participants underwent blind assessment, including Objective Structured Assessment of Technical Skills (OSATS), surgical time, and radiograph usage.Results:Expert evaluation of the simulation model indicated high satisfaction with anatomical representation, handling properties, and utility as a training tool. The expert group consistently outperformed novices at the initial assessment across all outcomes, demonstrating OSATS scores of 24 points (range, 23 to 25) versus 15.5 (range, 12 to 17), median surgical time of 22.75 minutes (range, 12 to 27) versus 48.75 minutes (range, 38 to 60), and median radiograph usage of 70 (range, 53 to 102) versus 232.5 (range, 112 to 280).Discussion:Novices exhibited a significant improvement in OSATS scores from the fifth session onward (P = 0.01), reaching the desired performance of 20 points. Performance at the final training with the simulated model did not differ from cadaveric surgery outcomes for all parameters.Conclusion:This study validated a simulation model and training program, allowing nonexperienced HV MIS foot and ankle surgeons to enhance their surgical proficiency and effectively complete a substantial portion of the learning curve at the fifth session, and this performance was successfully transferred to a cadaver model.
  • Thumbnail Image
    Item
    Preliminary Radiographic Classification of First Metatarsal Osteotomy Healing Following Minimally Invasive Hallux Valgus Surgery
    (2025) Lewis, Thomas L.; Mehrotra, Sanjana; Kaplan, Jonathan; González, Tyler; Morales, Sergio; Goff, Thomas J.; Vikramman, Vignaraja; Newton, Ayla Claire; Ray, Robbie; Lam, Peter
    Background: Minimally invasive or percutaneous surgery (MIS) for hallux valgus correction has seen increased adoption because of a growing evidence base of positive clinical and radiographic outcomes following surgery. However, no standardized or validated radiographic classification exists to evaluate the first metatarsal osteotomy healing following MIS hallux valgus surgery. The aim was to develop a new radiographic classification system for assessing bone healing following MIS distal transverse osteotomy for hallux valgus. Methods: A 4-domain radiographic classification system based on callus formation, anteroposterior (AP) osteotomy line, lateral osteotomy line, and remodeling for MIS osteotomy healing was developed and tested on a cohort of 27 feet that underwent percutaneous transverse osteotomy for hallux valgus correction. Patients had simultaneous postoperative weightbearing computed tomography (WBCT) and standard radiographs following surgery. Five surgeons reviewed anonymized radiographs to evaluate interobserver reliability. WBCT was used to confirm union status and classification interpretation. Results: The classification system demonstrated substantial interobserver reliability for lateral osteotomy line (Fleiss kappa = 0.671, 95% CI 0.505-0.814) and AP osteotomy line assessment (Fleiss kappa = 0.664, 95% CI 0.459-0.811), with moderate agreement for callus formation (κ = 0.465) and remodeling (κ = 0.439). The classification showed strong correlation with WBCT findings, with an optimal threshold of 8 points identified to differentiate union from nonunion, achieving an overall classification accuracy of 85.2%. This finding was supported by the area under the receiver operating characteristic (ROC) curve of 0.832. At the optimal threshold, the classification demonstrated 90.0% sensitivity and 71.4% specificity for detecting union. Conclusion: This preliminary classification provides a reliable tool for assessing first metatarsal bone healing following MIS hallux valgus osteotomies, with substantial interobserver reliability. It offers a standardized approach for radiographic evaluation, which may enhance comparability across studies and serve as a radiographic research tool pending further validation. Its clinical applicability remains to be determined.Level of Evidence: Level III, diagnostic study.