The aberrant anterior tibial artery: magnetic resonance appearance, prevalence, and surgical implications.

Background: Injury of a popliteal fossa artery during orthopaedic knee surgery is very rare but has serious consequences. The risk of vascular trauma during orthopaedic procedures may be increased when there is abnormal branching of the popliteal artery with an aberrant anterior tibial artery originating above the popliteus muscle and coursing between the posterior tibial cortex and ventral margin of the popliteus muscle. Preoperative identification of this anatomical variant may help avoid these injuries.
Hypothesis: The aberrant anterior tibial artery is present in a substantial portion of the population and can be visualized by magnetic resonance imaging.
Study Design: Cross-sectional study; Level of evidence, 3.
Methods: Retrospective review of 1116 consecutive knee magnetic resonance imaging studies was performed to evaluate the prevalence of an aberrant anterior tibial artery. Images were reviewed by 3 musculoskeletal radiologists.
Results: The aberrant anterior tibial artery was present in 23 of 1116 extremities for a prevalence of 2.1%. The aberrant artery was most easily identified on axial and sagittal magnetic resonance imaging scans.
Conclusion: The aberrant anterior tibial artery is a relatively common normal variant, and magnetic resonance is an excellent modality for detection of the artery close to the posterior joint capsule and tibial cortex.
Clinical Relevance: The anatomy suggests the aberrant anterior tibial artery may be at greater risk of injury in orthopaedic procedures such as high tibial osteotomy, revision total knee arthroplasty, lateral meniscal repair, posterior cruciate ligament reconstruction, and screw fixation for tibial tubercle osteotomy. Careful inspection of preoperative magnetic resonance imaging studies may alert the surgeon to the presence of this anatomical variant.