In a 3-part proximal humerus fracture model, the study aimed to compare an external fixation system’s primary stability and displacement tendencies in two distinct configurations to locking plate fixation. The stripped proximal humerus specimens from 21 fresh-frozen human cadaveric proximal humerus specimens were sorted into three groups of seven. The proximal humerus was set in an unstable three-part fracture. Construct A was made up of the Galaxy Fixation Shoulder System, which Researchers used according to the manufacturer’s instructions (3 pairs of threaded wires). According to Gumina et al.’s advice, Construct B was fixed by investigators with an additional pair of threaded wires (4 pairs of threaded wires). A looking plate was used to fix the remaining 7 specimens. During a cyclic loading process, relative motion at the fracture site and failure load were measured using an optical motion capture device.
Plate osteosynthesis (895± 239 N; range, 597 – 1135 N) had the highest cyclic load to failure, followed by construct B (692± 121 N; range, 432 – 788 N) and construct A (350± 190 N; range, 139 – 615 N). Between plating and construct A (P<.001), plating and construct B (P=.031), and construct B, the study group discovered a (P=.013), statistically significant differences. Relative motion at the fracture site, as measured by changes in the distance during cyclic loading, was lowest in construct B (1.73± 1.98 mm; range 0.53 – 5.96 mm) and highest in construct A (8.46± 10.67 mm; range 2.26 – 20.79 mm) at the peak load of 395 N after 11 steps (1.73± 1.98 mm; range 0.53 – 5.96 mm). After 11 steps, the angular shift recorded at the peak load was lowest in construct B (1.19± 0.36°; range 0.59± 1.7°) and highest in construct A (2.44± 1.63°; range 0.77 – 4.04°). At various stages of cyclic loading, statistically significant differences between construct A and B and build A and plates were discovered by them. Locking plate osteosynthesis revealed the highest feasible load application in this biomechanical evaluation of unstable 3-part proximal humerus fractures. When compared to locking plates, external fixator application with 8 threaded wires (construct B) demonstrated the slightest relative motion at the fracture site with no statistically significant difference. As a result, it represents yet another viable therapy option for primary stability. Adopting this technique with six threaded wires (construct A) resulted in the least stable structure and the fastest displacement rates.
Reference:www.jshoulderelbow.org/article/S1058-2746(22)00262-2/fulltext
