The increasing prevalence of proximal humerus fractures in the elderly population, particularly osteoporotic fractures, necessitates a biomechanical evaluation of Kirschner wire (K-wire) configurations used in percutaneous fixation. This study investigates the stability of different K-wire configurations and examines the effect of wire size and type (smooth vs. threaded). Using 27 synthetic humeri models, we compare three configurations as follows: four parallel ascending K-wires (box-type), two ascending and two descending K-wires, and a combination of both. Results show that adding descending K-wires significantly enhances stability, particularly against torsional forces. This study highlights the importance of wire type and configuration in stabilizing proximal humerus fractures. Multiplanar constructs with descending K-wires, especially threaded ones, offer better stability. These insights help improve surgical techniques for elderly and osteoporotic patients, but further research using cadaver models is needed for clinical validation.
Read full abstract