Seong Jong Yun, Presenter: Nothing to Disclose

Wook Jin, Abstract Co-Author: Nothing to Disclose

Gou Young Kim MD, PhD, Abstract Co-Author: Nothing to Disclose

Jae Hoon Lee MD, Abstract Co-Author: Nothing to Disclose

Woo Jin Yang, Abstract Co-Author: Nothing to Disclose

Kyung Jin Lee MD, Abstract Co-Author: Nothing to Disclose

Ji Su Kim, Abstract Co-Author: Nothing to Disclose

Sohee Yoon MD, Abstract Co-Author: Nothing to Disclose

So Young Park, Abstract Co-Author: Nothing to Disclose

Jung Eun Lee, Abstract Co-Author: Nothing to Disclose

Ji Seon Park MD, PhD, Abstract Co-Author: Nothing to Disclose

Kyung Nam Ryu MD, PhD, Abstract Co-Author: Nothing to Disclose

To retrospectively determine the prevalence and image findings of extra-articular talocalcaneal coalition with os sustentaculi (extra-articular TCC with OS), which is undescribed type of the TCC.

This retrospective two-center study was approved by the Institutional ReviewBoard and written informed consent was waived for adult patients. This study was queried through a database containing the radiology reports of CT or MR imaging that was performed during August 2001 to November 2013. Patients in our study were identified through a keyword search in our database for “TCC,” “tarsal coalition,” “coalition.” or “OS”. All radiologic examinations of patients with reports indicating a coalition in each institution were reviewed, based on the consensus of two musculoskeletal radiologists. Chart review was used to identify demographic information by one independent radiologist who did not involve image evaluation.

At two institutions, coalition was diagnosed in 81 patients. Among them, TCC was diagnosed in 66.7% (54/81) and naviculo-medial cuneiform coalition was diagnosed in 16.0% (13/81). The extra-articular TCC with OS was diagnosed in 13 patients (9 men, 4 women), which represents an incidence of 16.0% (13/81) in all coalitions and 24.1% (13/54) in all TCCs. The mean age of the patients was 27.8 years. Four of 13 patients underwent surgical resection and histology was obtained in 3 patients. Eight of 9 atraumatic patients were symptomatic and all patients with bone marrow edema at coalition sites on MR were symptomatic. Coexistence of extra-articular TCC with OS and other type TCCs was in 11 of 13 patients.

The OS has been diagnosed simply as an accessory ossicle or misdiagnosed as an old fracture. However, the OS may be a component of extra-articular TCCs, and was usually related to the presence of symptoms.

If a patient with OS has symptom in the medial talocalcaneal joint area, a new type of extra-articular TCC with OS should be considered.

Yun, S, Jin, W, Kim, G, Lee, J, Yang, W, Lee, K, Kim, J, Yoon, S, Park, S, Lee, J, Park, J, Ryu, K, New Type of Talocalcaneal Coalition with Os Sustentaculi: The Continued Necessity of Revision of Classification.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14007806.html