Lower extremity compartmental anatomy: clinical relevance to radiologists

A thorough understanding of compartmental anatomy is necessary for the radiologist participating in the care of a patient with a lower extremity musculoskeletal malignancy. Localization of tumor to compartment of origin and identification of extracompartmental spread preoperatively are needed to correctly stage a tumor and determine the appropriate surgical management. An understanding of the locations of fascial boundaries, extracompartmental tissues, and neurovascular structures of the thigh and lower leg facilitates this diagnostic process. For the radiologist planning to biopsy a suspicious musculoskeletal lesion, consultation with the referring orthopaedic surgeon is recommended in order to jointly select an appropriate percutaneous biopsy approach. Adequate preprocedural planning ensures selection of an approach which prevents iatrogenic tumor spread beyond the compartment of origin, protects neurovascular structures, and allows complete resection of the biopsy tract and scar at the time of surgical resection without jeopardizing a potential limb-sparing procedure. Cross-sectional anatomic review and case examples demonstrate the importance of a detailed understanding of compartmental anatomy when approaching the patient with a lower extremity musculoskeletal tumor.