Yu-Ching Lin MD, Presenter: Nothing to Disclose

Jennifer Nimhuircheartaigh MBBCh, Abstract Co-Author: Nothing to Disclose

Joshua Lamb, Abstract Co-Author: Nothing to Disclose

Justin Wen-Jseng Kung MD, Abstract Co-Author: Nothing to Disclose

Corrie Marlene Yablon MD, Abstract Co-Author: Nothing to Disclose

Jim Sweg-Hong Wu MD, Abstract Co-Author: Research Grant, Kaneka Corporation

The purpose of this study is to determine if radiographic foot measurements can predict injury of the posterior tibial tendon (PTT) and the supporting structures of the medial longitudinal arch as diagnosed on MRI.

Following institutional review board approval, 100 consecutive patients with radiographic and MRI exams performed within a 2 month time period were enrolled. Thirty-one patients had PTT dysfunction clinically and 69 patients had other causes of ankle pain. Talonavicular uncoverage angle, incongruency angle, calcaneal pitch angle, Meary’s angle, cuneiform-to-5th metatarsal height, and talar tilt were calculated on standing foot/ankle radiographs. MRI was used to assess for abnormalities of the PTT (tenosynovitis, tendinopathy, tear) and supporting structures of the medial longitudinal arch (spring ligament, deltoid ligament, sinus tarsi). Statistical analysis was performed using the chi-squared and Fisher’s exact tests for categorical variables; t-test was used for continuous variables.

There was a significant association of PTT tear with abnormal talonavicular uncoverage angle, calcaneal pitch angle, Meary’s angle, and cuneiform-to-5th metatarsal height. PTT tendinopathy and isolated tenosynovitis had a poor association with most radiologic measurements. If both calcaneal pitch and Meary’s angles were normal, no PTT tear was present. An abnormal calcaneal pitch angle had the best association with injury to the supporting medial longitudinal arch structures.

Radiographic measurements, especially calcaneal pitch and Meary’s angles, can be useful in detecting PTT tears. Calcaneal pitch angle provides the best assessment of injury to the supporting structures of the medial longitudinal arch.

Knowledge of this information can help guide the clinician and radiologist to determine which patients may benefit from additional clinical and imaging workup.

Lin, Y, Nimhuircheartaigh, J, Lamb, J, Kung, J, Yablon, C, Wu, J, Imaging of Adult Flatfoot: Correlation of Radiographic Measurements with MRI.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14001206.html