Ultrasound Arthroscopy of Hip in Treatment of Osteochondritis Dissecans  Antti Joukainen, M.D., Ph.D., Tuomas Virén, Ph.D., Pekko Penttilä, M.D., Jukka Liukkonen, Ph.D., Pia Henriikka Puhakka, Ph.D., Heikki Kröger, M.D., Ph.D., Juha Töyräs, Ph.D.  Arthroscopy Techniques  Volume 6, Issue 4, Pages e1063-e1068 (August 2017) DOI: 10.1016/j.eats.2017.03.022 Copyright © 2017 Arthroscopy Association of North America Terms and Conditions

Fig 1 (A) Plain radiographic image of right proximal femur (posterior-anterior direction). (B) Magnetic resonance image of right proximal femur (proton density, coronal plane) with site of osteochondritis dissecans (OCD) lesion magnified. (C) Anterior and anterolateral arthroscopic portals used to conduct ultrasound arthroscopy. (D) Representative ultrasound image of OCD lesion in coronal plane (ultrasound [US] catheter in anterior portal). (E) Arthroscopic view of OCD lesion (arthroscope in anterolateral portal). Ultrasound (US) imaging provided highly detailed information on the OCD lesion. The real-time evaluation of the extent of the lesion, as well as the assessment of the cartilage inner structures and subchondral bone, was possible. Arthroscopy Techniques 2017 6, e1063-e1068DOI: (10.1016/j.eats.2017.03.022) Copyright © 2017 Arthroscopy Association of North America Terms and Conditions

Fig 2 Arthroscopic and ultrasound images of intact cartilage in acetabulum (ultrasound catheter in anterolateral portal) and osteochondritis dissecans (OCD) lesion in femoral caput (ultrasound catheter in anterior portal). The ultrasound catheter and arthroscope were inserted into the hip by use of the anterior and anterolateral portals. Measurement of OCD lesion depth, as well as evaluation of the integrity of the cartilage inner structures and subchondral bone, was possible with the arthroscopic ultrasound technique. Furthermore, the calculation of quantitative parameters reflecting the status of the cartilage layer was possible. The quantitative ultrasound parameters are shown above the ultrasound images. (AIB, apparent integrated backscattering; R, reflection coefficient; URI, ultrasound roughness index.) Arthroscopy Techniques 2017 6, e1063-e1068DOI: (10.1016/j.eats.2017.03.022) Copyright © 2017 Arthroscopy Association of North America Terms and Conditions

Fig 3 Retrograde drilling of a right hip osteochondritis dissecans (OCD) lesion was possible under arthroscopic ultrasound guidance. (A) Arthroscopic view of OCD lesion from anterolateral portal. (B) Ultrasound image of OCD lesion in coronal plane, showing drill underneath cartilage surface (dashed red box). The ultrasound (US) catheter was inserted into the joint from the anterior portal. (C) Fluoroscopic image of hip (posterior-anterior direction) showing ultrasound (US) catheter, arthroscope, and drill. Arthroscopy Techniques 2017 6, e1063-e1068DOI: (10.1016/j.eats.2017.03.022) Copyright © 2017 Arthroscopy Association of North America Terms and Conditions