A Pictorial Review of Congenital Tarsal Coalition

Transcription

1 A Pictorial Review of Congenital Tarsal Coalition Poster No.: C-2305 Congress: ECR 2011 Type: Educational Exhibit Authors: J. Jethwa, M. Tapp; Torquay/UK Keywords: Musculoskeletal joint, Musculoskeletal system, Paediatric, Conventional radiography, CT, MR, Congenital DOI: /ecr2011/C-2305 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 45

2 Learning objectives To improve knowledge of the different types of tarsal coalition and their imaging findings. To gain an understanding of how these patients present clinically and when to suspect the diagnosis. To have a clearer insight into the imaging management of these patients and the strengths and weaknesses for the various coalitions with different imaging modalities. Page 2 of 45

3 Background Congenital tarsal coalition is an abnormal union between two or more tarsal bones. Coalitions may be osseous, cartilaginous or fibrous. The morphological subclassification of coalitions is really a contiuum begining as cartilaginous, progressing to fibrous and finally ossifying and these subtypes may coexist. Calcaneonavicular and talocalcaneal are the most common types of coalition accounting for 90% of all tarsal coalitions. Other sites such as talonavicular and calcaneocuboid are encountered much less frequently. The overall prevalence is estimated to be 1-2%. An autosomal dominant pattern of inheritance with variable penetrance has been suggested. The condition is bilateral in approximately 50%. Fused, or partially fused, tarsal bones result in abnormal articulations within the mid and hindfoot. The altered biomechanics frequently result in pain, difficulty in walking and early accelerated osteoarthritis. Clinically, there is a variability in both the onset and severity of symptoms. Clinical presentation is more likely with the progressive ossification of a coalition. Calcaneonavicular coalitions are more likely to present sooner than talocalcaneal as they ossify earlier. Overall, presentation is usually in late childhood or early adolescence, although a proportion of patients will remain asymptomatic throughout their adult lives. Patients often present with pain or stiffness in the mid or hindfoot. Alternatively, they may present with recurrent sprains with plain radiographic imaging available from the 'Emergency Room'. The condition is associated with pes planus. Page 3 of 45

4 Imaging findings OR Procedure details In the next section the imaging managemnt of these pateints is reviewed together with many examples of the various types of coalitions using multiple image modalities. Fig.: TABLE 1 Page 4 of 45

5 Fig.: TABLE 2 Page 5 of 45

6 Fig.: TABLE 3 Page 6 of 45

7 Fig.: TABLE 4 Page 7 of 45

8 Fig.: 1. There are bilateral fibrocartilaginous calcaneonavicular coalitions. Page 8 of 45

9 Fig.: 2. Another example of bilateral fibrocartilaginous calcaneonavicular coalitions. Page 9 of 45

10 Fig.: 3. A calcaneonavicular coalition can be strongly suspected from this lateral radiograph showing an elongated anterior calcaneal process and there is also associated pes planus. Page 10 of 45

11 Fig.: 4. There is a bridging bar between the calcaneum and navicular but this is incomplete suggesting either a non-osseous coalition or one that is still in the process of evolving into an osseous coalition. Page 11 of 45

12 Fig.: 5. Bony bridging bar in osseous calcaneonavicular coalition. Page 12 of 45

13 Fig.: 6. The 'ant eater' sign in calcaneonavicular coalition. Page 13 of 45

14 Fig.: 7. CT showing a non osseous fibrocartilagenous coalition between the calcaneum and navicular with associated accelerated osteoarthritis of both bones. Page 14 of 45

15 Fig.: 8. CT Saggital reformat showing the narrowed joint space between the calcaneum and navicular with cortical irregularity. Further images revealed associated cysts and degenerative changes. This is a non-osseous fibrocartilaginous coalition. Page 15 of 45

16 Fig.: 9. Saggital STIR image showing a low signal connection of fibrous coallition between the calcaneum and the navicular bones. Page 16 of 45

17 Fig.: 10. Coronal T1 weighted image showing reduction in joint space and early degenerative changes in an incomplete fibrocartilaginous calcaneonavicular coallition. Page 17 of 45

18 Fig.: 11. Saggital STIR image of a calcaneonavicular coalition with cartilige crossing it. Also note the increased bone oedema around the coalition as a result of abnormal stress loading. The following three images are from the same patient showing different views of an osseous calcaneonavicular coalition with a fracture through it: Page 18 of 45

19 Fig.: 12. Saggital T1 weighted image showing a calcaneonavicular coallition. The bone marrow signal extends across the gap, indicating that this is a bony coallition. The low signal line crossing the bony bridge is consistent with a fracture. Page 19 of 45

20 Fig.: 13. Saggital STIR image of the same patient showing bone marrow oedema around the fracture through the bony calcaneonavicular coallition. Page 20 of 45

21 Fig.: 14. T1 axial of the same patient showing the fracture through the bony coalition. Page 21 of 45

22 Fig.: TABLE 5 Page 22 of 45

23 Fig.: 15. AP and oblique views suggestive of talocalcaneal coalition. Page 23 of 45

24 Fig.: 16. The 'C' sign and Pes Planus. Fig.: 17. Pes planus and the 'C' sign in talocalcaneal coalition. Note also the superior talar beak. Page 24 of 45

25 Fig.: 18. Lateral radiograph showing a flattened curve of the talar dome in a ball and socket mortice resultant from a talocalcaneal coalition. Page 25 of 45

26 Fig.: 19. AP radiograph demonstrating the curved talar ball in the the ball and socket mortice related to a talocalcaneal coalition. Page 26 of 45

27 Fig.: 20. A non-osseous coalition of the subtalar joint. Note the cortical irregularity and joint space narrowing of the fibro-cartilaginous coalition. Page 27 of 45

28 Fig.: 21. Note the accelerated degenerative changes around the narrowed subtalar joint and the talar beak in keeping with a non-osseous union between the calcaneum and talus. Page 28 of 45

29 Fig.: 22. Complete osseous talocalcaneal fusion across the left middle and anterior facets as well as cortical irregularity across the right middle facet indicating a nonosseous coalition here. Page 29 of 45

30 Fig.: 23. CT showing osseous talcalcaneal fusion at the left posterior facet. Page 30 of 45

31 Fig.: 24. Coronal reformats showing a complete coalition on the left and a partial or non-osseous coalition on the right. Note the associated accelerated changes of osteoarthritis. The following three images are from the same patient who had an arthrogram following previous inconclusive investigations: Fig.: 25. This patient had a bilateral CT arthrogram when talocalcaneal coalition was suspected from the plain x-xrays. There is evidence of bilateral non-osseous talocalcaneal coalition. Page 31 of 45

32 Fig.: 26. The same patient, with an axial reformat of the left ankle. Page 32 of 45

33 Fig.: 27. Same patient with a sagittal reformat of the CT arthrogram of the left ankle showing subtalar joint space narrowing and cortical irregularity together with secondary changes of osteoarthritis, supporting a diagnosis of non-osseous talocalcaneal coalition. Page 33 of 45

34 Fig.: 28. T1 Saggital image showing irregularity and reduced joint space between the talus and the calcaneum in keeping with a fibrous coalition. Page 34 of 45

35 Fig.: 29. There is irregularity and reduced joint space between the talus and the calcaneum at the medial facet joint seen on this coronal T1 image. Page 35 of 45

36 Fig.: 30. Axial proton density fat saturation image. There is a mixed bony and cartilagenous coalition between the the talus and calcaneum. Page 36 of 45

37 Fig.: 31. T1 coronal image showing irregularity and joint space narrowing with intermediate signal within this space in keeping with a fibrocartilaginous coalition. Also note the decreased signal around the rest of the subtalar joint due to active arthropathy. Page 37 of 45

38 Fig.: 32. Proton density axial image showing a different view of the irregularity at the medial facet joint due to the coalition. Page 38 of 45

39 Fig.: 33. Saggital T2 fat saturation image. Note the extensive oedema around the subtalar joint with an irregular joint surface at the anterior talocalcaneal coalition. Page 39 of 45

40 Fig.: 34. Axial proton density fat saturation image. This shows the coalition of the same patient from a different view. Other combinations of coalitions such as talonavicular or calcaneocuboid are very rare. The following two images are from the same patient which show multiple coalitions coexisting in the same patient: Page 40 of 45

41 Fig.: 35. Plain radiographs showing multiple hindfoot coalitions between the talus, calcaneum, navicular and cuboid bones. The resultant altered biomechanics has caused a pes planus and early arthropathy in the remaining midfoot joints. Page 41 of 45

42 Fig.: 36. Ankle views in the same patient as above with the multiple osseous hindfoot coalitions. Page 42 of 45

43 Conclusion Congenital tarsal coalition is an important cause of foot and ankle pain in young patients. Diagnosis can often be made with conventional radiography, even when the diagnosis is not clinically suspected. The importance of early diagnosis is in guiding definitive imaging, which assists in early management decisions. Where conservative management has failed, surgical intervention is indicated and this may have a more favourable outcome if performed before ossification of the coalition occurs. Page 43 of 45

44 Personal Information Dr. Jalpesh Jethwa, Specialist Registrar in Radiology. Dr. Martin Tapp, Consultant Radiologist. Radiology Department, Torbay Hospital, South Devon Healthcare NHS Trust, Torquay, Devon, TQ2 7AA, England. Page 44 of 45

45 References Joel S. Newman, MD and Arthur H. Newberg, MD Congenital Tarsal Coalition: Multimodality Evaluation with Emphasis on CT and MR Imaging March 2000 RadioGraphics, 20, Julia Crim, Radiologic Clinics of North America Imaging of Tarsal Coalition Volume 46, Issue 6, Pages Pediatric Orthopedic Radiology - (1992) by M. B. Ozonoff pages 391, Wheeless' Textbook of Orthopaedics, With special thanks to Dr Philip White, Consultant Radiologist Torbay Hospital and Dr Richard Seymour, Consultant Radiologist Torbay Hospital for their contribution in providing images for this poster. Page 45 of 45