Vol.:(0123456789) 1 3 Archives of Orthopaedic and Trauma Surgery https://doi.org/10.1007/s00402-019-03112-y ARTHROSCOPY AND SPORTS MEDICINE The Extension–Thickness–Damage (ETD) score: a pre-operative hip MR arthrography-based classifcation to predict type of labrum surgery Alberto Aliprandi 1  · Marco Brioschi 2  · Sandro Magnani 3  · Silvana Sdao 4  · Domenico Albano 5  · Luca Maria Sconfenza 5,6  · Filippo Randelli 7 Received: 16 April 2018 © Springer-Verlag GmbH Germany, part of Springer Nature 2019 Abstract Introduction Hip magnetic resonance arthrography (MRA) is the pre-operative imaging modality of choice in patients with labral damage, with several classifcations of labral tears having been reported based on MRA fndings. Nevertheless, none of the available classifcation systems allows the surgeon to predict before surgery how a labral tear could be treated. Our purpose was to develop a new MRA-based scoring system of labral tears to predict before surgery the treatment option more suitable for labral tears. Materials and methods Forty-seven patients (29 males and 18 females; mean age: 35.9 ± 12.4) performed hip MRA for suspicious of femoroacetabular impingement and were afterwards subjected to arthroscopic treatment. Two musculoskel- etal radiologists reviewed all pre-operative examinations and provided the Extension–Thickness–Damage score for each patient, based on Extension of tear, Thickness of labrum, and type of Damage. Chondral lesions grading was based on the arthroscopic fndings according to Konan classifcation. For statistical purposes, patients were divided into two groups, depending on the type of treatment: labral repair or debridement. Mann–Whitney U, Chi-square, receiver operator curves, and Cohen kappa statistics were used. Results 35/47 underwent repair, while 12/47 were debrided. In both groups, the median chondral damage was grade III, with no signifcant diferences (p = 0.439). The median Extension–Thickness–Damage score in the repair group (6) was signif- cantly lower (p < 0.001) than that in the debridement group (8). The highest diagnostic performance (area under the curve) of Extension–Thickness–Damage was 0.819. The inter-observer agreement was substantial in the evaluation of Extension (k = 0.626) and Thickness (k = 0.771), and almost perfect for Damage (k = 0.827). Higher scores of Extension and Thickness were more frequently associated with debridement (p < 0.001; p = 0.0016, respectively), with no signifcant diferences on the basis of Damage parameter (p = 0.284). Conclusions The MRA-based Extension–Thickness–Damage score could represent a helpful pre-operative tool, expressing the extent of the damage and its reparability before arthroscopy. Keywords Magnetic resonance arthrography · Hip · Labrum · Tear · Arthroscopy * Domenico Albano albanodomenico@me.com 1 Radiology Unit, Istituti Clinici Zucchi, Via Bartolomeo Zucchi, 24, 20052 Monza, Italy 2 Postgraduate School in Orthopedic Surgery, Università degli Studi di Milano, Via Pascal 36, 20135 Milan, Italy 3 Postgraduate School in Radiodiagnostics, Università degli Studi di Milano, Via Festa del Perdono 7, 20122 Milan, Italy 4 Department of Radiology, Ospedale Alessandro Manzoni, Via dell’Eremo 9, 23900 Lecco, Italy 5 Unit of Diagnostic and Interventional Radiology, IRCCS Istituto Ortopedico Galeazzi, Via Riccardo Galeazzi 4, 20161 Milan, Italy 6 Department of Biomedical Sciences for Health, Università degli Studi di Milano, Via Pascal 36, 20135 Milan, Italy 7 Hip Department, Orthopedics and Trauma, IRCCS Policlinico San Donato, Via Morandi 30, San Donato Milanese 20097, Italy