Surgical factors associated with symptomatic implant removal after patella fracture

To determine whether certain types of fixation and other factors associated with the fixation could be identified that predict an increased risk of symptomatic implant removal.

We conducted a retrospective cohort study at our urban academic level 1 trauma center. Patients aged ≥18 years who underwent operative fixation for patella fracture were included. The primary outcome was symptomatic implant removal after operative fixation.

Of the 186 study patients (mean age, 44 [SD 17] years, 65% male), 53 patients (28.5%) underwent symptomatic implant removal. Modifiable risk factors for symptomatic implant removal included the use of Kirschner (k)-wires (OR: 4.93; 95% CI, 1.89-14.10; p < 0.001), and a trend towards significance for implant prominence >5 mm (OR: 2.57; 95% CI, 0.93-7.93; p = 0.07). Symptomatic implant removal was also less likely in patients >45 years of age (OR: 0.14; 95% CI, 0.06-0.34; p < 0.01), of a racial minority (OR: 0.40; 95% CI, 0.17-0.88; p = 0.03), and a body mass index >25 kg/m² (OR: 0.39; 95% CI, 0.18-0.84; p = 0.02). The final model demonstrated excellent prognostic performance, with an AUC of 0.83 (0.76-0.90).

We identified both modifiable and non-modifiable factors associated with symptomatic implant removal in patients with patella fractures. Surgeons should be aware that the use of k-wires and any implant prominence exceeding 5 mm might be associated with increased odds of symptomatic implant removal in patients with patella fractures.