Sangoh Lee1,2, Ines Oliveira3, Ian Pressney4, Matthew Welck5, Asif Saifuddin6,7. 1. Department of Clinical Imaging, Imperial College Healthcare NHS Trust, Praed Street, London, W2 1NY, UK. sangoh.lee@nhs.net. 2. Royal National Orthopaedic Hospital NHS Trust, Brockley Hill Stanmore, HA7 4LP, UK. sangoh.lee@nhs.net. 3. Royal National Orthopaedic Hospital NHS Trust, Brockley Hill Stanmore, HA7 4LP, UK. ines.oliveira1@nhs.net. 4. Royal National Orthopaedic Hospital NHS Trust, Brockley Hill Stanmore, HA7 4LP, UK. 5. Royal National Orthopaedic Hospital NHS Trust, Brockley Hill Stanmore, HA7 4LP, UK. matthewwelck@nhs.net. 6. Royal National Orthopaedic Hospital NHS Trust, Brockley Hill Stanmore, HA7 4LP, UK. asif.saifuddin@nhs.net. 7. Everlight Radiology, Level 6, West, 350 Euston Rd, London, UK. asif.saifuddin@nhs.net.
Abstract
OBJECTIVE: Hindfoot valgus malalignment has been assessed on coronal MRI by the measurement of the tibio-calcaneal (TC) angle and apparent moment arm (AMA). This study aimed to determine if the calcaneofibular ligament (CFL) angle could be used as a further marker of hindfoot valgus malalignment on routine non-weight-bearing ankle MRI. MATERIAL AND METHODS: One hundred ninety-five consecutive 3-T ankle MRI studies were identified from the hospital PACS system. The TC and CFL angles could be measured in 155 cases (78%), and the AMA on 153 cases. RESULTS: The study group comprised 56 males and 72 females with a mean age of 46 years (range 4-89 years). In 27 patients, both ankles had been imaged. The Pearson correlation between the TC and CFL angles was -0.43, with a corresponding p value of 0.001 indicating a strong negative correlation between the TC and CFL angles. The CFL angle was significantly lower in those with hindfoot valgus (113 ± 14) compared with those without (123° ± 15°) (p = 0.001). The optimal cut-off point of the CFL angle for hindfoot valgus was ≤119°, with a sensitivity and specificity of 66% and 63% respectively. The Pearson correlation between the CFL angle and AMA was -0.10, with a corresponding p value of 0.21 indicating a weak negative correlation that did not reach statistical significance. CONCLUSION: Hindfoot valgus as estimated by the increased TC angle on coronal non-weight-bearing ankle MRI is associated with a reduced CFL angle on sagittal MR images, but is not associated with AMA. Therefore, a horizontal orientation of the CFL on sagittal MR images may be a further useful sign of hindfoot valgus.
OBJECTIVE: Hindfoot valgus malalignment has been assessed on coronal MRI by the measurement of the tibio-calcaneal (TC) angle and apparent moment arm (AMA). This study aimed to determine if the calcaneofibular ligament (CFL) angle could be used as a further marker of hindfoot valgus malalignment on routine non-weight-bearing ankle MRI. MATERIAL AND METHODS: One hundred ninety-five consecutive 3-T ankle MRI studies were identified from the hospital PACS system. The TC and CFL angles could be measured in 155 cases (78%), and the AMA on 153 cases. RESULTS: The study group comprised 56 males and 72 females with a mean age of 46 years (range 4-89 years). In 27 patients, both ankles had been imaged. The Pearson correlation between the TC and CFL angles was -0.43, with a corresponding p value of 0.001 indicating a strong negative correlation between the TC and CFL angles. The CFL angle was significantly lower in those with hindfoot valgus (113 ± 14) compared with those without (123° ± 15°) (p = 0.001). The optimal cut-off point of the CFL angle for hindfoot valgus was ≤119°, with a sensitivity and specificity of 66% and 63% respectively. The Pearson correlation between the CFL angle and AMA was -0.10, with a corresponding p value of 0.21 indicating a weak negative correlation that did not reach statistical significance. CONCLUSION: Hindfoot valgus as estimated by the increased TC angle on coronal non-weight-bearing ankle MRI is associated with a reduced CFL angle on sagittal MR images, but is not associated with AMA. Therefore, a horizontal orientation of the CFL on sagittal MR images may be a further useful sign of hindfoot valgus.
Entities:
Keywords:
Hindfoot; Lower limb; MRI; Tibio-calcaneal angle; Valgus
Authors: Anna Hirschmann; Christian W A Pfirrmann; Georg Klammer; Norman Espinosa; Florian M Buck Journal: Eur Radiol Date: 2013-09-26 Impact factor: 5.315
Authors: Alexej Barg; Richard L Amendola; Heath B Henninger; Ashley L Kapron; Charles L Saltzman; Andrew E Anderson Journal: Foot Ankle Int Date: 2015-06-26 Impact factor: 2.827