MRI risk factors for development of avascular necrosis after closed reduction of developmental dysplasia of the hip: Predictive value of contrast-enhanced MRI

Abstract

Purpose The purpose of this study was to identify imaging risk factors on contrast-enhanced hip MRI after closed reduction of developmental dysplasia of the hip (DDH) that could predict future development of avascular necrosis (AVN) of the femoral head. Materials and methods Fifty-eight infants (F: M = 53: 5, aged 3–18 months) who underwent immediate postoperative contrast-enhanced hip MRI after closed reduction of DDH were included in this study. Quality of reduction (concentric vs eccentric reduction with or without obstacles), abduction angle of the hip, presence of ossific nucleus, and pattern of contrast enhancement of the femoral head were retrospectively evaluated on MRI. Interobserver agreement of contrast enhancement pattern on MRI were evaluated by two radiologists. Development of AVN was determined through radiographic findings at 1 year after reduction. Results AVN of the femoral head developed in 13 (22%) of 58 patients. Excessive abduction of the hip joint (OR 4.65, [95% CI 1.20, 18.06] and global decreased enhancement of the femoral head (OR 71.66, [95% CI 10.54, 487.31]) exhibited statistically significant differences between the AVN and non-AVN groups (P < 0.05). Eccentric reduction (P = 0.320) did not show statistically significant difference between two groups and invisible ossific nucleus (P = 0.05) showed borderline significance. Multi-variable logistic regression indicated that global decreased enhancement of the femoral head was a significant risk factor of AVN (OR 27.92, 95% CI [4.17, 350.18]) (P = 0.0031). Interobserver agreement of contrast enhancement pattern analysis and diagnosis of AVN were good (0.66, 95% CI [0.52, 0.80]). Conclusion Contrast-enhanced hip MRI provides accurate anatomical assessment of the hip after closed reduction of DDH. Global decreased enhancement of the femoral head could be used as a good predictor for future development of AVN after closed reduction of DDH.

Risk factors for postoperative avascular necrosis of the femoral head in children with developmental dysplasia of the hip

“…First, this study was a single-center retrospective study, which had a relatively poor sample representation and limited patient data. Global decreased enhancement of the femoral head, redislocation, and surgical treatment without femoral shaft shortening were found to be risk factors for postoperative ANFH ( 25 – 27 ). Since the retrospective nature of this study, some data cannot be obtained at present, and more factors need to be evaluated in the future.…”

Severity of hip dysplasia as the major factor affecting outcome of closed reduction in children with hip dysplasia

“…Given its less invasive nature, closed reduction is generally preferred to open reduction whenever possible [26]. However, treatment with closed reduction has been associated with adverse outcomes including AVN of the femoral head and insufficient long-term reduction of the hip requiring a second revision procedure [15][16][17][18]. It remains unclear which patients are most at risk of experiencing these complications and which would benefit the most from this treatment.…”

“…Recent studies have reported success rates ranging from 54.5% to 95.7% in patients treated with closed reduction [1,[8][9][10][11][12][13][14]. Despite these high success rates, the procedure has also been associated with complications including avascular necrosis (AVN) and failure of long-term maintenance of reduction requiring secondary reconstructive procedures [15][16][17][18]. Currently, there is variability in the literature that describes the rates of these complications following treatment with closed reduction and factors associated with these complications.…”

Pediatric Hip Disorders

“…또한, 수술 전후 대퇴골두의 동심성 정복을 제한하는 장애물을 평가할 수 있는데, 비대해진 섬유지방 조직(pulvinar) 또는 비구 내로 뒤집힌 관절순(labrum) 등이 대퇴골두와 비구 사이에 끼어 있는지 등을 평가한다( Fig. 4B ) ( 7 ). 고관절 석고 고정(hip spica cast)이 적용된 상태에서는 일반적인 고관절 초음파 검사 방법 대신, 전방 고관절 초음파 검사(van Douveren’s method)를 이용해 대퇴골두의 정복 여부를 평가할 수 있으며, 투과도 확보를 위해 저주파수 볼록 트랜스듀서를 사용할 수 있고 해상도 손실은 불가피하지만 쉽게 검사할 수 있다는 장점이 있다( Fig.…”