Type III Popliteal Artery Branching Variants: Morphometric Characterization, Preoperative CTA Assessment, and Clinical Implications for Lower-Leg Flap Surgery: A Cohort Study and Meta-Analysis
Year: 2026
Type: preprint
Abstract: Background. This study aimed to systematically characterize the prevalence and morphometric features of Type III popliteal artery branching variants in a computed tomography angiography (CTA) cohort of Chinese patients, and to derive global prevalence estimates and identify sources of heterogeneity via meta-analysis. Methods. This retrospective cohort comprised 235 consecutive patients (470 lower extremities) who underwent bilateral lower-extremity CTA between April 2020 and December 2024. Branching patterns were classified according to the Kim-Lippert system. CTA images were reviewed for popliteal artery branching and anatomical variations. Morphometric assessment included proximal diameters at the tibiofibular neck, terminal diameters of compensatory vessels, hypoplasia/aplasia classification, termination-point localization, and target-artery-to-peroneal-artery (PA) diameter ratios. Four databases were searched for the meta-analysis. Pooled prevalence was estimated using a random-effects model with Freeman-Tukey double arcsine transformation. Results. Type III variants were identified in 24 patients (10.21%) and 32 limbs (6.81%), comprising Type IIIA (3.19% limbs), IIIB (2.55% limbs), IIIC (0.21% limbs), and IIID (0.85% limbs). Two atypical peri-ankle collateral-dominant patterns were observed in 5 limbs (1.06%). Target-artery reductions were pronounced, with proximal diameter reductions of 31.9–33.3% accompanied by reciprocal PA enlargement of 15.3–16.9% proximally and 23.6–25.6% terminally. The target-artery-to-PA ratio reversed from 1.25 in normal limbs to 0.73 in IIIA and 0.65 in IIIB. Across 30 studies (10,351 limbs), pooled prevalences were 90.93% for Type I, 3.30% for IIIA, 1.46% for IIIB, 0.56% for IIIC, and 0.13% for IIID, with moderate to substantial heterogeneity (I² = 46.1–87.1%). Meta-regression showed that CT-based detection was associated with lower Type IIIC prevalence, and larger sample size as predictive of lower IIID prevalence. Conclusions. Type III popliteal artery variants were relatively common in this cohort of Chinese patients. In IIIA and IIIB, tibial deficiency was accompanied by peroneal artery enlargement, whereas IIID showed peroneal deficiency with preserved tibial runoff; IIIC was too rare for morphometric inference. Recognition of these patterns on preoperative CTA, including atypical peri-ankle collateral variants, is therefore prudent to ensure safe performance of lower-extremity microsurgical and orthopedic procedures. Trial registration: Not applicable.
Source: Research Square
Language: English
Subfield: Surgery
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W7225787274
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