Cable versus cerclage wire in weber tension band fixation for transverse olecranon fractures: a biomechanical study in a synthetic ulna model.

Stable fixation of displaced simple transverse olecranon fractures is required to maintain reduction under triceps traction and enable early elbow motion. Although Weber tension band fixation is widely used, the biomechanical influence of tension band material (cable vs cerclage wire) across different pin/anchorage designs remains unclear. This study compared resistance to fracture-line separation among six Weber-based constructs in a standardized synthetic ulna model. Sixty commercially available synthetic ulnae were osteotomized to create a transverse olecranon fracture model (Mayo type IIA) and randomly assigned to six groups (n = 10/group): bicortical pins, eyelet pins, and AA crimp constructs, each combined with either cable or cerclage wire in a figure-of-eight configuration. Specimens underwent monotonic tensile loading simulating triceps traction. Forces corresponding to 2 mm and 3 mm fracture-line separation were recorded. Between-group comparisons were performed within cable and cerclage subgroups, and cable-versus-cerclage comparisons were conducted within matched constructs (α = 0.05). At 2-mm separation, mean forces (N) were 316.1 ± 98.1 (bicortical cable), 277.0 ± 101.7 (eyelet cable), and 249.1 ± 104.2 (AA crimp cable), versus 273.1 ± 34.4 (bicortical cerclage), 283.6 ± 38.4 (eyelet cerclage), and 282.2 ± 36.9 (AA crimp cerclage). At 3-mm separation, mean forces were 340.5 ± 129.6, 336.5 ± 111.0, and 319.4 ± 78.8 for the cable constructs, and 332.9 ± 48.3, 354.7 ± 42.4, and 349.0 ± 37.2 for the cerclage constructs (bicortical, eyelet, and AA crimp, respectively). No significant differences were observed among pin/anchorage designs within the cable or cerclage subgroups at either threshold (all p > 0.05). Similarly, cable versus cerclage comparisons within matched constructs showed no significant differences at 2 mm or 3 mm (all p > 0.05). Under the specific conditions of this synthetic ulna model and monotonic tensile loading protocol, no statistically significant differences were detected between cable- and cerclage wire-based Weber tension-band constructs at either the 2-mm or 3-mm separation threshold. Bicortical, eyelet, and AA-crimp-based configurations also showed no significant differences in early gapping resistance. These findings should be interpreted as controlled monotonic early-separation data and not as evidence of clinical equivalence or fatigue durability.