Background Sacral insufficiency fractures (SIFs) are often overlooked in elderly patients presenting with low back and pelvic pain following no or minimal trauma. Objective The aim of this review is to raise awareness and outline the clinical presentation, methods of diagnosis and treatment of SIFs. Discussion Insufficiency fractures represent a special category of stress fractures that occur in bones with reduced mineral content and elastic resistance. SIFs, a well-defined subgroup of the latter group, are not uncommon, but lack of clinical suspicion results in many being undiagnosed. SIFs are set to become an important clinical entity of both social and economic significance as the Western population ages. Subtle clinical presentations and signs coupled with radiographic findings that can mimic other unrelated or overlapping conditions, such as sacroiliac joint infection, spinal stenosis and metastatic bone disease, often make SIF diagnosis a challenge. The aim of this review is to increase awareness among clinicians, highlighting SIFs as an important differential diagnosis to be considered when patients present with low back and pelvic pain and subsequently allow prompt management. The paper provides an overview of epidemiology, anatomical considerations, relevant pathophysiology and risk factors, presenting symptoms and signs, investigations and imaging techniques, differential diagnoses and current treatment methods available for the management of SIFs.
Keywords Minimal trauma . Sacral insufficiency fractures . Stress fractures
Epidemiology and cost of care
Osteoporotic fractures of the pelvic ring are not uncommon; however, they have been largely unrecognised, as until recently there was only scarce information in the literature. Data presented from the Finish computer-based population register have shown that the incidence of osteoporotic pelvic fractures requiring admission to hospital in Finnish women 60 years of age and older rose significantly between 1970 and 1997-from 20 to 95 per 100,000 people, respectively [1]. Furthermore, in a follow-up study by the same group of investigators, the number of pelvic fractures occurring following a minor trauma in the highest risk group among women aged 80 years or older also increasedfrom 35,421 in 1970 to 134,727 in 2002 [2]. A gross calculation estimated that the numbers will tripple by the year 2030 [2]. The latter conclusion, however, may be attributed to the current raised awareness of osteoporotic pelvic fractures and advanced radiological methods for their investigation and also to the fact that the mean age of patients increased from 74 years in 1970 to 80 years in 1997.
Sacral insufficiency fractures (SIFs) are a well-defined subgroup of insufficiency fractures. Since their original description by Lourie [3] in1982, several case reports and short case series have been published stressing the subtle clinical and radiological features associated with these fractures (Table 1). The incidence of SIFs remains