S. Ettinger (Hannover, DE)
Orthopedic Clinic Medical School Hannover at Diakovere Annastift Foot and Ankle SurgeryPresenter Of 1 Presentation
P074 - Validation of Open and Arthroscopic Size Measurement of Osteochondral Lesions of the Ankle in Comparison with Arthrography Imaging
Abstract
Purpose
For the treatment of talar osteochondral lesions (OCLT) the defect size is highly relevant. In addition to intraoperative defect size measurement, preoperative planning by means of magnetic resonance imaging (MRI) or computed tomography (CT) is crucial.
Methods and Materials
Four defects each of different sizes and depth were created on the talus (anteromedial/-lateral, posteromedial/-lateral) in a total of 14 cadaver feet. All defects were evaluated by each of three foot and ankle surgeons arthroscopically and via a mini-arthrotomy. Arthro-MRI and high resolution flat panel CT arthro (FPCT-A) scans were acquired. Two radiologists independently performed size measurement of every OCLT on MRI and data. Length, width and depth were measured for every defect and the defect volume was calculated. To determine the exact defect size and volume, each talar defect was filled with plastic pellets. The defect impressions were scanned in an FPCT, in order to create a 3D multiplane reconstruction data set for measurement of the exact defect size and volume. Finally, the surgically measured values were compared with the radiological values and the exact defect size.
Results
Surgically measured values for defect length, width and depth underestimated the exact defect size, both arthroscopically and open (p<0.05). Arthroscopically determined defect length and width showed the largest deviation compared to the exact size (p<0.05). The measured CT values demonstrated higher correlation with the surgical measurements, both arthroscopically and open, compared to MRI measurements (p<0.05). The defect depth was determined most accurate with an FPCT scan compared to the exact defect size (p<0.05). The calculated surgically determined defect volume overestimated the exact defect volume (p<0.05).
Conclusion
The measured FPCT defect sizes displayed higher correlation with the surgically measured values compared to the MRI. However, the exact defect size is underestimated surgically. FPCT-A scan is best qualified to assess defect depth.
Presenter Of 1 Presentation
P074 - Validation of Open and Arthroscopic Size Measurement of Osteochondral Lesions of the Ankle in Comparison with Arthrography Imaging
Abstract
Purpose
For the treatment of talar osteochondral lesions (OCLT) the defect size is highly relevant. In addition to intraoperative defect size measurement, preoperative planning by means of magnetic resonance imaging (MRI) or computed tomography (CT) is crucial.
Methods and Materials
Four defects each of different sizes and depth were created on the talus (anteromedial/-lateral, posteromedial/-lateral) in a total of 14 cadaver feet. All defects were evaluated by each of three foot and ankle surgeons arthroscopically and via a mini-arthrotomy. Arthro-MRI and high resolution flat panel CT arthro (FPCT-A) scans were acquired. Two radiologists independently performed size measurement of every OCLT on MRI and data. Length, width and depth were measured for every defect and the defect volume was calculated. To determine the exact defect size and volume, each talar defect was filled with plastic pellets. The defect impressions were scanned in an FPCT, in order to create a 3D multiplane reconstruction data set for measurement of the exact defect size and volume. Finally, the surgically measured values were compared with the radiological values and the exact defect size.
Results
Surgically measured values for defect length, width and depth underestimated the exact defect size, both arthroscopically and open (p<0.05). Arthroscopically determined defect length and width showed the largest deviation compared to the exact size (p<0.05). The measured CT values demonstrated higher correlation with the surgical measurements, both arthroscopically and open, compared to MRI measurements (p<0.05). The defect depth was determined most accurate with an FPCT scan compared to the exact defect size (p<0.05). The calculated surgically determined defect volume overestimated the exact defect volume (p<0.05).
Conclusion
The measured FPCT defect sizes displayed higher correlation with the surgically measured values compared to the MRI. However, the exact defect size is underestimated surgically. FPCT-A scan is best qualified to assess defect depth.