The relationship between alpha angle and resistive index of the femoral epiphysis in the normal and abnormal infant hip

Perfusion Changes in Acute Septic Arthritis of the Hip Joint During Infancy Using Doppler USG

Objectives

To quantitatively assess vascularity changes of acute septic hips in infants using Doppler ultrasonography. To compare these findings with asymptomatic hips, and establish a correlation for accurate diagnosis between these findings.

Methods

In this prospective case-control study, we included all children under 1 year of age with a diagnosis of acute septic arthritis of the hip in the case group. For the control group, we enrolled apparently healthy, full-term neonates and infants not affected with any hip pathology. Doppler ultrasound of the medial femoral circumflex artery of the hip joint was done using a single Phillips HDI 5000 sonography machine. Following parameters were studied: peak systolic velocity (PSV), resistive index (RI), pulsatility index (PI), and systolic to diastolic ratio (SD ratio).

Results

Doppler signals and spectral waveforms were obtainable in 100% of hips in both groups. A statistically significant difference was found between the cases and controls with respect to their PSVs, RIs, PIs and SD ratios. The most striking difference was found between the PSVs of the two groups, whose mean was 6.18 in the control group and 11.8 in the case group. No significant correlation between age/gender and any of the 4 parameters was found.

Conclusion

Doppler parameters are useful in raising suspicion of onset in the diagnosis of septic arthritis. No correlation was found between age or gender and any parameter in control group. These baseline values can be held valid for all children below the age of 7 months.

Colour Doppler Ultrasound Assessment of the Normal Neonatal Hip

Objective

To determine the morphology and hemodynamic characteristics of the arterial vessels of the proximal femur according to specific anatomic regions in asymptomatic neonates in 2 pediatric-based health care institutions.

Methods

Forty-three neonates (29 female, 14 male; age range, 2 d–3 mo; median age, 3 d) were enrolled in the study. Thirty-two (37%) of 86 hips were classified as Graf type IIA joints (mean alpha angle, 56.0° ± 2.7°), and 54 (63%) were classified as type I joints (mean alpha angle, 65.0° ± 4.6°).

Results

Colour and spectral Doppler imaging identified vessels running along the acetabular labrum, epiphyseal vessels, and femoral neck. We showed 4 different patterns of vascularity of the hips: radial, parallel, mixed radial–parallel, and indeterminate, however, they were not related to the hip maturity ( P = .3, coronal plane; P = .62, transverse plane) or to the amount of colour pixels identified in each region ( P = .35). The mean number of pixels in the ligamentum teres region was significantly higher than that in other regions of interest ( P = .03). Except for the acetabular labrum arteries, Doppler spectrum waveforms of proximal femur arteries presented with low resistivity. There was a tendency towards females' acetabular arteries presenting with lower peak systolic velocities than males' acetabular arteries ( P = .06).

Conclusions

Colour Doppler spectrum waveforms and intensity of vascularity in normal neonatal hips differ according to the anatomic region under evaluation. This observation deserves further investigation on its role on the physiopathogenesis of neonatal hip disorders.

Legg-Calvé-Perthes disease: multipositional power Doppler sonography of the proximal femoral vascularity

BACKGROUND

Selection of the most appropriate sonographic scanning approaches for evaluation of hips can improve the method efficacy and decrease the scanning time.

OBJECTIVE

To determine the sonographic scanning planes that best assess the proximal femoral vascularity in asymptomatic and pathologic hips of children with Legg-Calvé-Perthes disease (LCPD) and evaluate the frequency (number of hips with evidence of perfusion) and intensity (number of color pixels per region) of color pixels representing superficial cartilaginous and deep transphyseal vascularity in different anatomic regions of pathologic and asymptomatic hips using multipositional power Doppler approaches.

MATERIALS AND METHODS

Seven scanning approaches (anterior-sagittal, anterior-transverse, coronal, adduction, perineal, 30 degrees and 70 degrees of abduction) were applied in 26 pathologic hips of 26 children with LCPD (age range 3-11 years) and in 25 contralateral asymptomatic hips. The color Doppler signals seen within the proximal femur were analyzed both qualitatively (overall/regional frequency) and quantitatively (intensity).

RESULTS

The coronal (P=0.009) and 30 degrees abduction (P=0.047) approaches demonstrated a higher frequency of color pixels in pathologic than in asymptomatic hips. The anterior-sagittal, 30 degrees abduction, adduction and anterior-transverse planes performed best of all approaches (P=0.02) to assess deep transphyseal perfusion. The physis demonstrated a greater intensity of color signals representing intraosseous vascularity than other regions in pathologic hips (P=0.027), as noted with the anterior-sagittal approach. There was a tendency (P=0.06) towards a greater intensity of pixels representing cartilaginous vascularity in pathologic hips' physes with the coronal approach.

CONCLUSION

Specific sonographic scanning planes are recommended for assessment of the proximal femoral vascularity of LCPD hips. The physis is the anatomic region that presents with the greatest intensity of color signals in pathologic hips.