The effect of distal locking mode on postoperative mechanical complications in intertrochanteric fractures: a retrospective cohort study of five hundred and seven patients.

PURPOSE

The optimal choice of distal locking modes remains a subject due to limited available data, and therefore, this study aims to investigate the relationship between distal locking mode and postoperative mechanical complications in an intertrochanteric fracture (ITF) population who underwent closed reduction and intramedullary fixation with a PFNA-II.

METHODS

Patients aged 65 years or older who underwent surgery with PFNA-II fixation in a university teaching hospital between January 2020 and December 2021 were potentially eligible. Based on the distal locking mode, patients were classified into static, dynamic, and limited dynamic groups, among which the differences were tested using univariate analysis. Multivariate logistic regression was used to examine whether the distal locking mode was independently associated with the risk of postoperative one year mechanical complications, adjusting for covariates and potential confounders. Subgroup analyses were performed to evaluate the robustness of the findings.

RESULT

Among 507 eligible patients, 33 (6.5%) developed postoperative mechanical complications. In the univariate analysis, sex (P = 0.007), fracture type (P = 0.020), LAT Parker ratio (P = 0.023), and lateral femoral (P = 0.003) wall showed that the differences were significant. Compared to the static group, the limited dynamic group and the dynamic group showed higher odds of postoperative mechanical complications (OR = 3.314, 95% CI: 1.215-9.041; and OR = 3.652, 95% CI: 1.451-9.191, respectively). These associations were robust across a series of analyses, including adjusting for confounders and subgroup analyses.

CONCLUSION

Using a distal non-static locking mode significantly increases the risk of postoperative mechanical complications, and static locking could be a preferable option when treating an intertrochanteric fracture.