144 Part I Chapter 5 Suggested diagnostic algorithm As TCs are a congenital condition and presentation is usually in the adolescent age and mostly at age younger than 50 years old, imaging with the least amount of ionizing radiation is preferred. We suggest the diagnostic algorithm showed in Figure 17 for optimal diagnosis in patients with (suspected) TC or unexplained tarsal pain at both primary diagnosis and (post-surgical) follow-up [Figure 17]. Figure 17. Proposed diagnostic algorithm for optimal diagnosis in patients with the (suspected) tarsal coalition or unexplained tarsal pain at both primary diagnosis and (post-surgical) follow-up. Discussion and recommendations Although the non-exhaustive list of indications in the EANM guidelines do not specifically mention tarsal coalitions, bone-SPECT/CT is an adequate imaging modality to accurately depict different types of TCs as an adjunct to plain radiograph imaging. In primary diagnosis it increases diagnostic value in especially TCC, as these can be challenging to be revealed using plain radiography. Bone-SPECT/CT also shows additional (secondary) osteoarthritis and/or other accompanying synchronous pathology in the foot or ankle, and is able to exclude accompanying bone pathology with high readers confidence. Planar blood pool images may aid in the diagnosis of TC with typically depicting focally increased radionuclide uptake.