Analysis of the sacroiliac joint vacuum phenomenon in paediatric patients

Abstract

Objective: To assess the incidence of the sacroiliac joint vacuum phenomenon (SIJ VP) in paediatric patients and the relationship between the presence of VP and clinical factors such as age, sex and body mass index (BMI). Methods: We retrospectively reviewed clinical data and imaging findings of 60 patients who underwent abdominopelvic CT (AP CT) between January and June 2015. Patients were divided into VP group and non-VP group based on the presence/absence of VP, and the groups were compared. In addition, other degenerative changes in the SIJ were recorded. Results: The SIJ VP was detected in 19 (31.6%) patients. There were no significant differences in sex distribution between VP and non-VP groups (p 5 0.781). The age of the VP group was significantly higher than that of the non-VP group (p , 0.001). After adjusting the BMI for age, there was no significant association between high BMI and the presence of SIJ VP (p 5 0.326). Other degenerative changes were not noted in any of the patients. Conclusion: The SIJ VP is not an uncommon finding in paediatric patients. The prevalence of SIJ VP in paediatric patients is similar to its prevalence in adults. The SIJ VP is related to patient age, but not to sex or BMI in children and young adolescents. Advances in knowledge: AP CT can provide information about the SIJ, if it is required to assess the SIJ in paediatric patients. INTRODUCTIONThe sacroiliac joint vacuum phenomenon (SIJ VP) is not an uncommon finding in adults.1-3 When radiologists face abdominopelvic CT (AP CT), little attention is paid to the SIJ. However, AP CT can provide information about the SIJ, if we attempt to observe the SIJ.1-3 The SIJ VP has been reported in approximately 31-34% of adults. 1,4 In addition, it is observed more frequently in females and in patients older than 60 years.1 Moreover, it is considered an age-related morphological variant, and obesity is believed to affect such degenerative changes in the SIJ. 4 To our knowledge, there has been no report on the SIJ VP among only paediatric patients, and data are lacking on its prevalence and clinical significance in this group. Based on our experience of reviewing AP CT images, we recognized that the SIJ VP is not unusual among paediatric patients as well. We hypothesized that the prevalence of SIJ VP among paediatric patients is similar to that among adults. The present study aimed to investigate the radiological findings of the SIJ using AP CT images and assess the incidence of the SIJ VP among paediatric patients. Furthermore, the

The Air Inside Joint: A Sign of Disease Pathology or a Benign Condition?

“…Although the presence of a vacuum phenomenon did not affect the lumbopelvic parameters in females, there was a significant decrease in pelvic incidence and sacral slope in males with a vacuum phenomenon [15]. A study by You et al concluded that prevalence of vacuum phenomenon in sacroiliac joint in children is the same as that of adults; however, they were not able to determine the association between degenerative changes in the sacroiliac joint and low back pain among children and adolescents [16] In acute open injury, the presence of air indicates communication of joint space to outside, even as an iatrogenic cause as in arthroscopy complicated by tension pneumoarthrosis [2]. The presence of intra-articular air may simulate meniscal and cartilaginous injury in the knee, but Miller et al and Wright et al showed the presence of air was actually associated with meniscal and bony injuries, respectively, in their patients` [12,17].…”

An Omitted Radiological finding in the Pediatric Age Group: Physiological Sacroiliac Joint Vacuum Normal Variant

“…2,3 Physiological forms of VP in the pediatric age group have been presumed to be a rare phenomenon. 4,5 As far as the authors could identify, articles in the English literature have been limited to normal variants of this condition. 5 However, condition may be more clinically important in children since because it can mimic inflammatory and infectious pathologies on magnetic resonance (MRI) and computed tomography (CT) imaging.…”

“…4,5 As far as the authors could identify, articles in the English literature have been limited to normal variants of this condition. 5 However, condition may be more clinically important in children since because it can mimic inflammatory and infectious pathologies on magnetic resonance (MRI) and computed tomography (CT) imaging. 6 In 2016, Takata et al evaluated the relationship between sacroiliac pelvic morphology and VP in all age groups.…”

“…6 In 2016, Takata et al evaluated the relationship between sacroiliac pelvic morphology and VP in all age groups. 7 The only pediatric research in this subject was the study of You et al 5 that compared the SIJ VP and body mass index (BMI) in pediatric patients and their study is based on obesity and degenerative VP relationship. 5 In another article from Lo et al, SIJ VP was classified in patients under 40 years old, 40-60 years old and over 60 years old without specifying pediatric patients.…”

“…7 The only pediatric research in this subject was the study of You et al 5 that compared the SIJ VP and body mass index (BMI) in pediatric patients and their study is based on obesity and degenerative VP relationship. 5 In another article from Lo et al, SIJ VP was classified in patients under 40 years old, 40-60 years old and over 60 years old without specifying pediatric patients. 4 In summary, the published articles have not focused on the physiological pediatric SIJ VP.…”