A delay in establishing the diagnosis of an occult
fracture of the hip that remains unrecognised after plain radiography
can result in more complex treatment such as an arthroplasty being
required. This might be avoided by earlier diagnosis using MRI.
The aim of this study was to investigate the best MR imaging sequence
for diagnosing such fractures. From a consecutive cohort of 771
patients admitted between 2003 and 2011 with a clinically suspected
fracture of the hip, we retrospectively reviewed the MRI scans of
the 35 patients who had no evidence of a fracture on their plain
radiographs. In eight of these patients MR scanning excluded a fracture
but the remaining 27 patients had an abnormal scan: one with a fracture
of the pubic ramus, and in the other 26 a T1-weighted
coronal MRI showed a hip fracture with 100% sensitivity. T2-weighted
imaging was undertaken in 25 patients, in whom the diagnosis could
not be established with this scanning sequence alone, giving a sensitivity
of 84.0% for T2-weighted imaging. If there is a clinical suspicion of a hip fracture with normal
radiographs, T1-weighted coronal MRI is the best sequence
of images for identifying a fracture.
The purpose of this study was to describe the anatomical distribution and incidence of fatigue injuries of the femur in physically-active young adults, based upon MRI studies. During a period of 70 months, 1857 patients with exercise-induced pain in the femur underwent MRI of the pelvis, hips, femora, and/or knees. Of these, 170 patients had a total of 185 fatigue injuries, giving an incidence of 199 per 100 000 person-years. Bilateral injuries occurred in 9% of patients. The three most common sites affected were the femoral neck (50%), the condylar area (24%) and the proximal shaft (18%). A fatigue reaction was seen in 57%, and a fracture line in 22%. There was a statistical correlation between the severity of the fatigue injury and the duration of pain (p = 0.001). The location of the pain was normally at the site of the fatigue injury. Fatigue injuries of the femur appear to be relatively common in physically-active patients.