Talocalcaneal coalition
Updates to Article Attributes
Body
was changed:
TheTalocalcaneal talocalcaneal coalition is one of the two most common subtypes of the tarsal coalition, the other being the calcaneonavicular coalition. It accounts for 45% of all tarsal coalitions, and although all three facets of the talocalcaneal joint can be involved, the middle facet is most commonly involved.
Pathology
Classification
Talocalcaneal coalitions can be classified according to their location into the following subtypes 2:
- anterior facet type
- middle facet type
- posterior facet type
-
extraarticular
- with or without os sustentaculi
Radiographic features
As with any coalition, it may be bony, cartilaginous or fibrous. Talocalcaneal coalition often requires cross-sectional imaging for accurate diagnosis.
Plain radiograph
Plain film findings include3,4:
-
C-sign
- best assessed on a lateral ankle radiograph
- posterior continuity of the talus and sustentaculum tali
3 - sensitivity: 50%
- specificity: 90%
-
talar beak sign
- best seen on the lateral ankle radiograph
- prominent beak at the anterior aspect of the talus
Secondary radiographic features that suggest the diagnosis include close apposition of the middle facet of the talocalcaneal (subtalar) joint or non-visualisation of the middle articular facet 1,4,5. Sclerosis around the articular margins of the talocalcaneal joint may also occur.
CT
At CT, coronal reformats are usually the best to appreciate the coalition. BonyThe bony coalition is seen as a complete bar of bone between the talus and calcaneus. In a non-osseous coalition, there is usually irregularity of the articular surface, narrowing of the joint space and subchondral sclerosis. CT might also nicely demonstrate the presence of an os sustentaculi.
MRI
MRI is more helpful for the assessment of cartilaginous or fibrous coalitions and also demonstrates bone marrow and soft-tissue oedema.
Nuclear medicine
On bone scan there is Increased radionucleotide uptake at the site of the coalition may occur due to altered biomechanics at the joint although this is a non-specific finding.
History and etymology
The talocalcaneal coalition was first described by the Austrian-Hungarian anatomist Emil Zuckerkandl in 1877 2.
-<p><strong>Talocalcaneal coalition</strong> is one of the two most common subtypes of <a href="/articles/tarsal-coalition">tarsal coalition</a>, the other being <a href="/articles/calcaneonavicular-coalition">calcaneonavicular coalition</a>. It accounts for 45% of all tarsal coalitions, and although all three facets of the <a href="/articles/talocalcaneal-joint">talocalcaneal joint</a> can be involved, the middle facet is most commonly involved. </p><h4>Radiographic features</h4><p>As with any coalition it may be bony, cartilaginous or fibrous. Talocalcaneal coalition often requires cross-sectional imaging for accurate diagnosis.</p><h5>Plain radiograph</h5><p>Plain film findings include:</p><ul>- +<p>The<strong> talocalcaneal coalition</strong> is one of the two most common subtypes of the <a href="/articles/tarsal-coalition">tarsal coalition</a>, the other being the <a href="/articles/calcaneonavicular-coalition">calcaneonavicular coalition</a>. It accounts for 45% of all tarsal coalitions, and although all three facets of the <a href="/articles/talocalcaneal-joint">talocalcaneal joint</a> can be involved, the middle facet is most commonly involved.</p><h4>Pathology</h4><h5>Classification</h5><p>Talocalcaneal coalitions can be classified according to their location into the following subtypes <sup>2</sup>:</p><ul>
- +<li>anterior facet type</li>
- +<li>middle facet type</li>
- +<li>posterior facet type</li>
- +<li>extraarticular<ul><li>with or without <a href="/articles/os-sustentaculi">os sustentaculi</a>
- +</li></ul>
- +</li>
- +</ul><h4>Radiographic features</h4><p>As with any coalition, it may be bony, cartilaginous or fibrous. Talocalcaneal coalition often requires cross-sectional imaging for accurate diagnosis.</p><h5>Plain radiograph</h5><p>Plain film findings include <sup>3,4</sup>:</p><ul>
-<li>posterior continuity of the talus and <a href="/articles/sustentaculum-tali">sustentaculum tali</a> <sup>3</sup>- +<li>posterior continuity of the talus and <a href="/articles/sustentaculum-tali">sustentaculum tali</a>
-</ul><p>Secondary radiographic features that suggest the diagnosis include close apposition of the middle facet of the talocalcaneal (subtalar) joint or non-visualisation of the middle articular facet <sup>1,4</sup>. Sclerosis around the articular margins of the talocalcaneal joint may also occur.</p><h5>CT</h5><p>At CT, coronal reformats are usually the best to appreciate the coalition. Bony coalition is seen as a complete bar of bone between the talus and calcaneus. In non-osseous coalition, there is usually irregularity of the articular surface, narrowing of the joint space and subchondral sclerosis.</p><h5>MRI </h5><p>MRI is more helpful for the assessment of cartilaginous or fibrous coalitions and also demonstrates bone marrow and soft-tissue oedema.</p><h5>Nuclear medicine</h5><p>On bone scan there is Increased radionucleotide uptake at the site of the coalition may occur due to altered biomechanics at the joint although this is a non-specific finding.</p>- +</ul><p>Secondary radiographic features that suggest the diagnosis include close apposition of the middle facet of the talocalcaneal (subtalar) joint or non-visualisation of the middle articular facet <sup>1,5</sup>. Sclerosis around the articular margins of the talocalcaneal joint may also occur.</p><h5>CT</h5><p>At CT, coronal reformats are usually the best to appreciate the coalition. The bony coalition is seen as a complete bar of bone between the talus and calcaneus. In a non-osseous coalition, there is usually irregularity of the articular surface, narrowing of the joint space and subchondral sclerosis. CT might also nicely demonstrate the presence of an os sustentaculi.</p><h5>MRI </h5><p>MRI is more helpful for the assessment of cartilaginous or fibrous coalitions and also demonstrates bone marrow and soft-tissue oedema.</p><h5>Nuclear medicine</h5><p>On bone scan there is Increased radionucleotide uptake at the site of the coalition may occur due to altered biomechanics at the joint although this is a non-specific finding.</p><h4>History and etymology</h4><p>The talocalcaneal coalition was first described by the Austrian-Hungarian anatomist Emil Zuckerkandl in 1877 <sup>2</sup>.</p>
References changed:
- 3. Taniguchi A, Tanaka Y, Kadono K, Takakura Y, Kurumatani N. C Sign for Diagnosis of Talocalcaneal Coalition. Radiology. 2003;228(2):501-5. <a href="https://doi.org/10.1148/radiol.2282020445">doi:10.1148/radiol.2282020445</a> - <a href="https://www.ncbi.nlm.nih.gov/pubmed/12819337">Pubmed</a>
- 4. Lateur L, Van Hoe L, Van Ghillewe K, Gryspeerdt S, Baert A, Dereymaeker G. Subtalar Coalition: Diagnosis with the C Sign on Lateral Radiographs of the Ankle. Radiology. 1994;193(3):847-51. <a href="https://doi.org/10.1148/radiology.193.3.7972836">doi:10.1148/radiology.193.3.7972836</a> - <a href="https://www.ncbi.nlm.nih.gov/pubmed/7972836">Pubmed</a>
- 5. Adam Greenspan. Orthopedic Imaging. (2004) ISBN: 9780781750066 - <a href="http://books.google.com/books?vid=ISBN9780781750066">Google Books</a>
- 2. Yun S, Jin W, Kim G et al. A Different Type of Talocalcaneal Coalition With Os Sustentaculum: The Continued Necessity of Revision of Classification. AJR Am J Roentgenol. 2015;205(6):W612-8. <a href="https://doi.org/10.2214/AJR.14.14082">doi:10.2214/AJR.14.14082</a> - <a href="https://www.ncbi.nlm.nih.gov/pubmed/26587950">Pubmed</a>
- 6. Zuckerkandl E. Ueber einen Fall von Synostose zwischen talus und calcaneus. Allg. Wiener Med Zeitung 1877; 22:293–294
- 2. Taniguchi A, Tanaka Y, Kadono K et-al. C sign for diagnosis of talocalcaneal coalition. Radiology. 2003;228 (2): 501-5. <a href="http://dx.doi.org/10.1148/radiol.2282020445">doi:10.1148/radiol.2282020445</a> - <a href="http://www.ncbi.nlm.nih.gov/pubmed/12819337">Pubmed citation</a><div class="ref_v2"></div>
- 3. Lateur LM, Van hoe LR, Van ghillewe KV et-al. Subtalar coalition: diagnosis with the C sign on lateral radiographs of the ankle. Radiology. 1994;193 (3): 847-51. <a href="http://radiology.rsna.org/content/193/3/847.abstract">Radiology (abstract)</a> - <a href="http://www.ncbi.nlm.nih.gov/pubmed/7972836">Pubmed citation</a><div class="ref_v2"></div>
- 4. Greenspan A. Orthopedic imaging, a practical approach. Lippincott Williams & Wilkins. (2004) ISBN:0781750067. <a href="http://books.google.com/books?vid=ISBN0781750067">Read it at Google Books</a> - <a href="http://www.amazon.com/gp/product/0781750067?ie=UTF8&tag=radiopaediaor-20&linkCode=as2&camp=1789&creative=9325&creativeASIN=0781750067">Find it at Amazon</a><div class="ref_v2"></div>
Unable to process the form. Check for errors and try again.