The clinical and radiographic characteristics of avascular necrosis after pediatric femoral neck fracture: a systematic review and retrospective study of 115 patients

Abstract

Background Avascular necrosis (AVN) after pediatric femoral neck fracture (PFNF) showed poor prognosis, but its clinical and radiographic characteristics remained unclear. Methods A systematic review and a retrospective study were performed to evaluate the clinical and radiographic characteristics of patients with AVN after PFNF. Results A total of 686 patients with PFNF and 203 patients with AVN from 21 articles were analyzed. Ratliff’s classification was used in 178 patients, with types I, II, and III AVN accounting for 58.4%, 25.3%, and 16.3%, respectively. Ratliff’s assessment was used in 147 patients, of whom 88.4% had an unsatisfactory prognosis. In retrospective study, 115 patients with a mean age of 13.6 ± 2.0 years were included. The mean interval between AVN and PFNF was 13.7 ± 9.5 months. At the time of diagnosis, 59.1% cases were symptomatic and 65.2% progressed to collapsed stage. Fifty (43.5%), 61 (53.0%), and 4 patients (3.5%) were defined as types I, II, and III , respectively, via Ratliff’s classification. Thirteen (11.3%), 40 (34.8%), and 62 patients (53.9%) showed types A/B, C1, and C2 disease, respectively, via the JIC classification. Multivariate analysis demonstrated a strong relation between collapsed stage and symptomatic cases (OR = 6.25, 95% CI = 2.39–16.36) and JIC classification (OR = 3.41, 95% CI = 1.62–7.17). Conclusion AVN after PFNF showed a tendency toward extensive necrotic lesions, presumably resulting in a rapid progression of femoral head collapse. And the symptoms and the JIC classification are other two risk factors of collapse progression.

Clinical observation and finite element analysis of cannulated screw internal fixation in the treatment of femoral neck fracture based on different reduction quality

“…Moreover, due to the rapid development of social economy, high-energy injuries caused by car accidents and falls from height are increasing, and the incidence of femoral neck fractures in young and middle-aged people is increasing year by year [ 4 ]. Young and middle-aged patients require joint function activities, so it is necessary to maintain the shape and function of the original joint through reduction as much as possible [ 5 , 6 ]. One study showed that the incidence of postoperative femoral head necrosis was 16% [ 7 ].…”

Experimental Study of 3D Printing Technique Combined with Biphasic Calcium Phosphates in the Treatment of Canine Model of Osteonecrosis of the Femoral Head

“…Several studies showed that the collapse rate of the lesion that exceeds 2/3 of the inner side of the weight bearing part is high. When the lesion extends laterally to the edge of the acetabulum, the femoral head collapse is more common [29][30][31] . The experimental group implanted BCP material in a prominent imaging position, with a basically intact structure and a columnar shape; Overall observation showed no collapse in the necrotic area of the femoral head.…”

The Role of Structural Deterioration and Biomechanical Changes of the Necrotic Lesion in Collapse Mechanism of Osteonecrosis of the Femoral Head

“…The necrotic lesion mostly occurs at the superior, medial, and anterior areas of the ischemic femoral head 32 . According to the Japanese Investigation Committee (JIC) classification system (Table 2 ), several studies had indicated that the lesion exceeding the medial 2/3 of the weight‐bearing portion had a higher collapse rate and a faster progression of stage, and femoral head collapse occurred more often when the lesion extended laterally to the acetabular edge 47 , 48 , 49 , 50 , 51 (Table 3 ). One explanation was that the changes of bone structure in weight‐bearing portion reduced the stress transfer efficiency of principal compressive trabeculae after osteonecrosis and caused severe damage to the load‐bearing capacity.…”