A Comparative Study of Doppler-Guided Acute Bone Shortening-Lengthening Versus Bone Transport for Infected Tibial...

The management of infected tibial bone defects with soft tissue defects (ITBD-STD) remains challenging. This study aims to establish a Doppler-guided safety threshold for acute shortening (≤ 3 cm), compare the clinical efficacy and safety of shortening-lengthening (S-L) versus bone transport (BT), quantify the complication burden, and clarify the calculation indices.

A retrospective analysis was conducted on the clinical data of 43 patients with ITBD-STD admitted between January 2021 and January 2024. All patients were treated using the Ilizarov circular external fixation technique and were divided into a bone S-L group and a BT group based on the surgical procedure. In the S-L group, acute shortening was performed under real-time Doppler guidance with a predefined safety cap of 3 cm. The wound healing time (WHT), bone healing index (BHI), external fixation index (EFI), and complication rate were compared and analyzed between the two groups. At a mean follow-up of 19.9 months, bone union and lower limb functional recovery were evaluated using the criteria of the Association for the Study and Application of the Ilizarov Method (ASAMI). Statistical analysis was performed using the independent sample t-test or the χ² test.

The WHT in the S-L group was significantly shorter than that in the BT group (68.5 ± 25.2 vs. 85.2 ± 21.5 days, p < 0.05). In the S-L group, acute shortening was successfully performed in all 22 patients under real-time Doppler guidance, with a mean acute shortening distance of 2.8 ± 0.4 cm (capped at 3 cm). No patient experienced Doppler signal loss or required intraoperative termination of shortening due to vascular compromise. The BHI (37.36 ± 10.73 vs. 44.14 ± 11.12 days/cm) and EFI (45.36 ± 11.23 vs. 53.52 ± 12.55 days/cm) in the S-L group were significantly lower than those in the BT group (all p < 0.05). However, there was no statistically significant difference in the overall complication rate between the two groups (45.5% vs. 42.9%, p > 0.05). At the final follow-up, there was also no statistically significant difference in ASAMI scores between the two groups (p > 0.05).

Both S-L and BT are effective for ITBD-STD with comparable safety. Under the strict Doppler-guided protocol (≤ 3 cm), S-L significantly shortens WHT without increasing complications, yet this benefit is design-inherent rather than a biological advantage. Given comparable ASAMI functional outcomes, S-L offers no functional superiority over BT. Nonetheless, the Doppler criteria and selection strategy established herein provide a safe, reproducible framework for technique selection, validating the clinical feasibility of acute shortening without compromising final function or safety.