title: Angle and Base of Gait Long Leg Axial and Intraoperative Simulated Weightbearing Long Leg Axial Imaging to Capture True Frontal Plane Tibia to Calcaneus Alignment in Valgus and Varus Deformities of the Rearfoot and Ankle.
abstract: The long leg axial view is primarily used to evaluate the frontal plane alignment of the calcaneus in relation to the long axis of the tibia when standing. This view allows both angular measurement and assessment for the apex of varus and valgus deformity of the rearfoot and ankle with clinical utility in the preoperative, intraoperative, and postoperative settings. The frontal plane alignment of the calcaneus to the long axis of the tibia is rarely fixed in the varus or valgus position because of the inherent flexibility of the foot and ankle, which makes patient positioning critical to obtain accurate and reproducible images. Inconsistent patient positioning and imaging techniques are commonly encountered with the long leg axial view for a variety of reasons, including the lack of a standardized or validated protocol. This angle and base of gait imaging protocol involves positioning the patient to align the tibia with the long axis of the foot, which is represented by the second metatarsal. Non-weightbearing long leg axial imaging is commonly performed intraoperatively, which requires a modified patient positioning technique to capture simulated weightbearing long leg axial images. A case series is presented to demonstrate our angle and base of gait long leg axial and intraoperative simulated weightbearing long leg axial imaging protocols that can be applied throughout all phases of patient care for various foot and ankle conditions.
authors.affiliation: Director, Foot and Ankle Surgical Residency Program, Regions Hospital/HealthPartners Institute for Education and Research, St. Paul, MN.
authors.forename: Troy J
authors.initials: TJ
authors.lastname: Boffeli
authors.affiliation: Foot and Ankle Surgery Resident, Regions Hospital/HealthPartners Institute for Education and Research, St. Paul, MN. Electronic address: brett.j.waverly@healthpartners.com.
authors.forename: Brett J
authors.initials: BJ
authors.lastname: Waverly
mesh_terms: D000328:Adult; D000368:Aged; D017760:Bone Malalignment / Q000000981:diagnostic imaging / Q000601:surgery; D002111:Calcaneus / Q000000981:diagnostic imaging / Q000601:surgery; D003198:Computer Simulation; D005260:Female; D005531:Foot Deformities, Acquired / Q000000981:diagnostic imaging* / Q000601:surgery*; D006801:Humans; D007430:Intraoperative Care / Q000379:methods; D008297:Male; D008875:Middle Aged; D019637:Orthopedic Procedures / Q000379:methods*; D010027:Osteotomy / Q000379:methods; D056888:Patient Positioning; D011859:Radiography / Q000379:methods; D020127:Recovery of Function; D012494:Sampling Studies; D013709:Tendon Transfer / Q000379:methods; D013977:Tibia / Q000000981:diagnostic imaging / Q000601:surgery; D016896:Treatment Outcome; D016474:Weight-Bearing / Q000502:physiology*
keywords: arthrodesis; frontal plane alignment; long leg axial; osteotomy; radiograph; rearfoot; trauma; valgus deformity; varus deformity