PhD Defence: Krisztián Balázs Kovács (Biomechanics of Acromioclavicular Joint Reconstruction)

Acromioclavicular (AC) joint injuries are among the most frequent shoulder girdle injuries—and despite the existence of 150+ surgical techniques, there is still no universally accepted gold standard for reconstruction. In this PhD defence, Krisztián Balázs Kovács, orthopaedic surgeon at Semmelweis University and PhD candidate at the Centre for Translational Medicine, presents translational research aimed at improving the biomechanical precision and clinical reliability of musculoskeletal interventions.

His thesis connects two key research directions:

1) Bone elasticity and implant-related precision
Finite element (FE) modelling and implant design require accurate Young’s modulus (elasticity) values, yet the literature reports major discrepancies depending on test method, specimen preparation, and bone microstructure. Through a comprehensive systematic review and meta-analysis, this project maps the key variables that drive variation in elasticity results—highlighting the impact of factors such as microstructure, test method, bone region, anisotropy, age, sex, condition, and sample size. The work emphasizes why standardization is essential if FE models are to be clinically valid and reproducible.

2) LockDown technique in AC joint reconstruction
The second project evaluates the LockDown synthetic ligament technique for AC joint reconstruction—an approach with limited reporting in Hungarian literature. Combining a systematic review with a prospective multicentre cohort study (Semmelweis University, Manninger Jenő Hospital, Hungarian Defence Forces Hospital), the thesis examines functional outcomes, subgroup differences (acute vs chronic; primary vs revision), and complications. The results suggest improved outcomes in acute and primary cases, while also documenting real-world complication patterns and the challenge of heterogeneous reporting in the field.

Overall, this defence highlights how biomechanics, surgical outcome research, and translational methodology can be integrated to move toward more reliable, individualized orthopaedic care, with future directions including CT-linked experimental validation and modelling of fracture risk (e.g., coracoid-related complications).