Magnetic resonance imaging of tibial shaft fracture repair

The role of ultrasound in monitoring reconstruction of mandibular continuity defects using osteogenic protein-1 (rhOP-1)

Introducing bone bioengineering concepts in craniofacial surgery demands development of novel imaging strategies, which overcome the shortcomings of radiography such as exposure to ionizing radiation. This study is aimed to investigate the usefulness of ultrasonography (US) in monitoring reconstruction of continuity osteoperiosteal mandibular defects in sheep using rhOP-1. The study was conducted on six adult sheep in which a critical size defect was created at the body of the mandible and was reconstructed using rhOP-1 with type-I collagen as a carrier. Ultrasound images were used to assess onset of bone formation, contour, and surface topography. The results were then compared to corresponding plain radiographs and to post-mortem observations. US showed bone union in all the subjects that concurred with radiographic and post-mortem examinations. US was superior to plain radiography in monitoring early events of ossification. However, it was relatively less efficient in describing the contour of the newly formed bone. It was possible to describe the pattern of bone formation and the dynamic changes in contour and surface topography via US during the follow-up period. In experienced hands, ultrasonography can offer valuable information about bone healing comparable with those obtained by plain radiography. US may replace plain radiography in becoming a routinely used tool for monitoring bone healing in selected sites of the craniofacial skeleton.

Ultrasonographic appearance of external callus in long-bone fractures

High-resolution real-time ultrasound (US) scanning was used to monitor serially 24 patients with an acute long-bone fracture and three patients with humeral non-union, looking at the fracture site over a period of 12 months following the fracture. In both these groups, we found that US gave important information about the soft tissues surrounding the fracture site, and indicated callus formation at an early stage. US was more sensitive than conventional radiography at showing the early phases of organization of the callus, and its progression to bridging new bone formation. US also clearly showed a disorganized echopattern at the fracture site of the patients with non-union.