Musculoskeletal trauma in paediatric practice: the experience from Marseille

Abstract

Imaging technology has progressed dramatically in the last 30 years. Flat panel high-resolution imaging, ultra-thin computed tomography (CT) sections with twoand threedimensional reformatting, and high-contrast and -resolution magnetic resonance imaging (MRI) with dedicated coils have changed our confidence in the exploration of bone trauma. CT and MRI have definitively increased our diagnostic abilities, particularly in children following polytrauma. However, polytrauma only accounts for a minority of trauma cases admitted to an emergency department. This presentation will instead focus on the daily reality. In a previous study performed over a 24-week period, we performed radiography in 3,128 anatomical locations in children admitted following trauma. Only 22% of the radiographic examinations were considered abnormal. In descending order, the hand and fingers, ankle, wrist, knee, elbow, foot and toes, and forearm were the most frequently examined locations. The rate of abnormal findings was 25.7% for the hand and fingers, 9.0% for the ankle, 42.5% for the wrist, 9.5% for the knee, 33.3% for the elbow, 18.3% for the foot and 43.2% for the forearm. When only the direct observation of a fracture was taken into account, these rates decreased for the ankle and knee to 2.6% and 1.9%, respectively. Over the past ten years, these two joints in particular have been the focus of our attention. Despite convincing data on the validity of the Ottawa Ankle Rules, referrals for ankle radiographs remain numerous. Our main explanation for this is the rotation in the emergency department of trainee doctors with various professional experiences and the fear of medicolegal proceedings. We have tried unsuccessfully in several projects to curtail these referrals. We have also investigated the underlying abnormality in swollen ankles when there was suspicion of sprain. Interestingly, in a series of 102 post-trauma MRI scans of ankles without radiographic fractures, we found only two ruptures of the lateral ligament in children with an open physis. Even more interesting, none of these had a classical Salter-Harris type I fracture of the distal fibula, which we believe is overdiagnosed. Two osteochondral avulsion fractures of the distal fibula, and microfractures of the foot were missed on radiographs. MRI has also been reported to be of high interest to modify the Salter-Harris classification of ankle fractures diagnosed on radiographs. However, our experience does not suggest this. In a series of 29 fractures, one patient was misclassified as Salter-Harris type III. MRI modified this classification to a Salter-Harris type III/Ogden type VI, but none of our patients had their therapeutic management changed following MRI. The point is that MRI of the ankle may show numerous abnormalities that are without clinical relevance. A delayed clinical examination, after three to four days’ immobilisation, may also obviate numerous unnecessary imaging procedures. Ultrasounds may have a place in imaging after this period of short immobilization to detect the rare case of rupture of the talofibular and calcaneofibular ligaments. However, expectancy is not suggested in knee trauma, where radiographs underestimate the severity of injury. CT or, even better, MRI must be performed as soon as a SalterHarris fracture is seen radiographically, or when there is Disclaimer Dr. Philippe Petit has no financial interests, investigational or off-label uses to disclose.