Single-end fixed angle locking screws in intramedullary nails for treatment of OTA 42 A-C tibial diaphyseal fractures are associated with increased nonunion risk
摘要
The purpose of this study was to compare fracture nonunion rates in tibial shaft fractures fixed with intramedullary nails using fixed angle locking screws (FALS) that thread into the intramedullary nail versus standard locking screws in a cohort of tibial diaphyseal fractures. Secondarily, this study evaluated whether FALS location was associated with nonunion risk in tibial diaphyseal fractures.
MethodsA retrospective review of surgically treated OTA 42 A-C tibial shaft fractures from 2014 to 2024 at a single academic institution was performed. Inclusion criteria were age > 18, isolated OTA 42 A-C tibia fracture, intramedullary nail fixation, and minimum 6-month follow-up. Patients treated with a FALS were matched to those without a FALS with a 1:1 propensity match based on OTA fracture classification and open fracture status. The Radiographic Union Score for Tibia (RUST) was used to determine healing. Statistical comparisons were performed using Pearson Chi-squared tests, independent t-tests, Mann Whitney-U tests, and multivariate logistic regression as appropriate.
Results78 patients were included (39 in each cohort), with the FALS group being older and having higher age-unadjusted Charlson Comorbidity Indices (CCI). The FALS and CLS groups had comparable rates of open fractures and similar proportions of OTA/AO fractures. FALS configuration per patient was: 16 only distal, 13 only proximal, and 10 both proximal and distal. There were no differences in nonunion rates (25.6% vs. 15.4%, p = 0.262) and healed-by times (6.15 ± 2.95 [months] vs. 6.38 ± 2.73, p = 759), complication rate, or 30/90-day readmission rates (p < 0.05). Multivariate analysis demonstrated that the use of single-end FALS (used only proximally or distally) was independently associated with higher odds of nonunion compared to CLS and FALS used both proximally and distally (OR = 6.027, p = 0.025).
ConclusionThe use of single-end fixed angle locking screws in only the distal or proximal segment in intramedullary nails for the treatment of OTA 42 A-C tibial diaphyseal fractures is associated with higher odds of fracture nonunion. Larger, prospective studies evaluating FALS configuration for intramedullary nail fixation of tibia shaft fractures are warranted.