Distal locking of intramedullary nails with reduced radiation exposure and operating time using standard equipment

Abstract

Aim: Distal locking during intramedullary nailing remains a technically demanding step. The aim of this study was two-fold: first, to evaluate whether the proposed locking technique reduces radiation exposure and operative duration compared with the conventional free-hand technique across surgeons with different levels of experience; second, to compare its performance with previously published alternative distal locking methods.

Methods: A retrospective observational study was conducted across three trauma centers in Belgium. A total of 432 patients undergoing intramedullary nailing for long-bone fractures were included. Thirty surgeons (10 junior residents, 10 senior residents, 10 board-certified surgeons) performed distal locking using both the conventional free-hand technique and the proposed method. Radiation exposure and procedure duration were recorded and compared. Results were also compared with published data on alternative distal locking techniques.

Results: The proposed technique significantly reduced radiation exposure, fluoroscopy time, and procedure duration across all experience levels. Mean radiation dose decreased from 35.47 ± 8.9 to 4.43 ± 1.1 cGy/cm² (p < 0.0001). Fluoroscopy time decreased from 19.33 ± 6.2 to 11.5 ± 2.0 seconds (p = 0.003). Procedure duration decreased from 9.53 ± 3.1 to 4.23 ± 1.2 minutes (p < 0.0001). The greatest improvement was observed among less experienced surgeons. Compared with published techniques, the method demonstrated non-inferior or superior results in terms of radiation exposure and procedure duration.

Conclusions: This simple and reproducible technique significantly reduces radiation exposure and operative time compared with the free-hand method. By eliminating the need to obtain a nearly perfectly round fluoroscopic image of the locking hole, the technique relies on hand-eye coordination and cognitive alignment rather than fixed geometric positioning. It requires fewer adjustments and repositioning of the C-arm. Its performance is comparable or superior to alternative techniques. It requires no additional equipment, making it practical for routine trauma practice.

Keywords

intramedullary nailing / femoral fracture / tibial fracture / distal locking / long bone fractures / radiation reduction / surgical technique

References

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