Grace C Kunas1, William Probasco1, Amgad M Haleem2, Jayme C Burket3, Emilie R C Williamson1, Scott J Ellis4. 1. Department of Foot and Ankle Surgery, Hospital for Special Surgery, 535 East 70th Street, New York, NY, 10021 USA. 2. Department of Orthopedic Surgery, Oklahoma University Health Sciences Center, 920 Stanton L Young Blvd., Williams Pavilion 1380, Oklahoma City, OK, 73104 USA. 3. Department of Epidemiology and Biostatistics, Hospital for Special Surgery, 535 East 70th Street, New York, NY, 10021 USA. 4. Department of Foot and Ankle Surgery, Hospital for Special Surgery, 535 East 70th Street, New York, NY, 10021 USA. Electronic address: EllisS@hss.edu.
Abstract
BACKGROUND: The aim of this study was to assess the inferior talus-superior talus (inf-tal-sup-tal) angle (previously proven reliable in multiplanar-weight bearing imaging (MP-WB)) on both computed tomography (CT) and MP-WB scans. We sought to compare the angle between the two modalities in both AAFD and control groups, as well as to compare the groups to each other. METHODS: Inf-tal-sup-tal angles were compared between a stage II AAFD group (n=38) with routine MP-WB and CT scans and a control group (n=20) with preoperative CT scans for lisfranc injuries and normal hindfoot alignment after healing. RESULTS: The CT inf-tal-sup-tal angle was significantly greater in AAFD compared to control (AAFD, 12±6; control, 5±4; p<0.001), but was even greater with MP-WB. There was no significant correlation between inf-tal-sup-tal angles on MP-WB and CT (Pearson's=0.29, p=0.08). CONCLUSIONS: MP-WB imaging proved to be correlated more strongly with AAFD than CT by revealing greater hindfoot valgus. This confirmed that CT scans are useful in predicting AAFD, but cannot be used as a surrogate for MP-WB scans.
BACKGROUND: The aim of this study was to assess the inferior talus-superior talus (inf-tal-sup-tal) angle (previously proven reliable in multiplanar-weight bearing imaging (MP-WB)) on both computed tomography (CT) and MP-WB scans. We sought to compare the angle between the two modalities in both AAFD and control groups, as well as to compare the groups to each other. METHODS: Inf-tal-sup-tal angles were compared between a stage II AAFD group (n=38) with routine MP-WB and CT scans and a control group (n=20) with preoperative CT scans for lisfranc injuries and normal hindfoot alignment after healing. RESULTS: The CT inf-tal-sup-tal angle was significantly greater in AAFD compared to control (AAFD, 12±6; control, 5±4; p<0.001), but was even greater with MP-WB. There was no significant correlation between inf-tal-sup-tal angles on MP-WB and CT (Pearson's=0.29, p=0.08). CONCLUSIONS: MP-WB imaging proved to be correlated more strongly with AAFD than CT by revealing greater hindfoot valgus. This confirmed that CT scans are useful in predicting AAFD, but cannot be used as a surrogate for MP-WB scans.
Authors: Nicola Krähenbühl; Amy L Lenz; Rich Lisonbee; Manja Deforth; Lukas Zwicky; Beat Hintermann; Charles L Saltzman; Andrew E Anderson; Alexej Barg Journal: J Orthop Res Date: 2019-02-12 Impact factor: 3.494