Factors Influencing Elbow Function after Internal Fixation of Complex Distal Humeral Fractures in Adults

Source

·        Wu JY, et al. Sci Rep. 2025 Aug 4;15(1):28437
[doi: 10.1038/s41598-025-13200-2]

 

Background

•       Distal fracture of the humerus is challenging due to numerous intricate structures including its relation to radius and ulna that need to be considered for anatomical reduction and internal fixation in cases of articular fractures.

•       These fractures are often high-energy trauma with significant fragmentation and soft tissue injury.

•       Fractures involving the capitellum, trochlea, medial and lateral condyles are more likely to have intraarticular extension.

•       Anatomical reduction, early elbow mobility, should maximize postoperative recovery and help prevent complications such as postoperative stiffness, and post-traumatic arthritis and instability.

•       In contrast to traditional ORIF approach, “arch support” where condylar restoration is prioritized provides theoretically better biomechanical function restoration when it comes to management of distal humerus fractures.

•       Biomechanical restoration here aims to maximize post-operative joint mobility and load bearing function.

 

Discussion

•       Post-ORIF recovery promoters:

•       Arch support principles + adequate amount of distal screws (generally > 3, but excessive amount, especially in osteoporotic patients, has poorer outcome, including implant failure, and iatrogenic fractures).

•       Range of motion, and joint fragments stability.

•       Save for some particular fractures of distal humerus, parallel plating (medial & lateral) is biomechanically superior to orthogonal plating (postero- lateral/medial + lateral/medial).

•       Greater axial stiffness, load to failure, and torsional stiffness.

•       Higher stiffness during cyclic various loading, and less screw lossening.

•       “Arch Support” principles aim to restore the medial and lateral humeral column together with the articular surface as one load-bearing arch:

•       Has higher MEPS score (biomechanical stability) vs otherwise.

•       Distributes load better evenly, more resistant to multidirectional stresses as opposed to simple anatomical reduction.

•       This may also be the reason why > 3 distal screws vs ≤ 2 distal screws yield better biomechanical stability and outcome, preventing micromotion-induced complications such as stiffness, arthritis or nonunion.

•       Post-ORIF recovery inhibitors:

•       Prolonged hospitalization compromises recovery.

•       Limited joint mobility.

•       Older age.

•       Poorer biomechanical stability increases risk of postoperative complications including synovial fibrosis, cartilage degeneration, PTOA, nonunion, heterotopic ossification.