Variabilidad en la medición del índice acetabular / Variability in measurement of acetabular index

Introducción: La Displasia del desarrollo de la cadera (DDC) es un espectro de enfermedades que abarca desde la luxación franca de la cadera hasta la displasia acetabular leve. El screening de detección de DDC se realiza de rutina en nuestro país, mediante una radiografía de pelvis a los 3 meses. El índice acetabular medido en estas radiografías se utiliza para evaluar la cadera displásica, tanto en la presentación inicial como durante el seguimiento posterior. Objetivo: Evaluar la variabilidad tanto intra como inter observador en la medición del índice acetabular, entre profesionales médicos. Material y Métodos: Cuatro evaluadores (un cirujano-ortopédico infantil, un médico general, un pediatra y un radiólogo) realizaron la medición del índice acetabular en 100 radiografías de screening (200 caderas), en tres ocasiones, separadas por un mes cada una (600 mediciones totales). Un observador independiente evaluó la reproductibilidad en la medición. Se utilizó el coeficiente de correlación intraclase para determinar diferencias significativas. Resultados: La variabilidad intra observador fue menor que la interobservador. La variabilidad intra observador fue similar para los diferentes evaluadores, +/- 1,5°. La variabilidad inter observador fue de +/- 3,4°. Conclusiones: Demostramos una alta concordancia entre las mediciones, determinando una alta reproductibilidad del índice acetabular. El índice acetabular es un método seguro para el diagnóstico y seguimiento de displasia acetabular.

Developmental dysplasia of the hip (DDH) is a spectrum of diseases ranging from frank dislocation of the hip to mild acetabular dysplasia. DDH screening for detection is performed routinely in our country using pelvic x-ray at 3 months of age. The radiographic measured acetabular index is used to evaluate the dysplastic hip, at initial presentation and during follow-up. Objective: Evaluation of the intra- and inter-observer variability, among medical professionals, when measuring acetabular index. Methods: Four reviewers (a children orthopedic surgeon, a general practitioner, a pediatrician and a radiologist) performed acetabular index measurement in 100 radiographs (200 hips), on three occasions, separated each by one month (600 total measurements). An independent observer evaluated the measurement reproducibility. The intra-class correlation coefficient to determine significant differences was used. Results: The intra-observer variability was less than the inter-observer variability. The intra-observer variability was similar among the different assessors, +/- 1.5 degrees. The inter-observer variability was +/- 3.4 degrees. Conclusions: A high concordance among measurements was reported, evidencing a high reproducibility of the acetabular index; this index is a reliable method for the diagnosis and follow-up of acetabular dysplasia.

Acetabular Development after Operative Treatment of Developmental Dislocation of the Hip / 대한정형외과학회잡지

PURPOSE: To examine the acetabular development after the surgical treatment of a developmental dislocation of the hip (DDH). MATERIALS AND METHODS: The serial radiographs of 27 hips were evaluated. The measurement included: acetabular index, CE angle, Smith's h/b, c/b ratio, medial joint space, and center-head distance discrepancy (CHDD). All the patients were followed up until they were at least 10 years old. The overall results were evaluated using the modified Severins classification (group I & II, satisfactory; group III & IV, unsatisfactory). RESULTS: In the satisfactory group, the average acetabular index at 1 and 3 years after the pelvic osteotomy was 6% were in the unsatisfactory group. CONCLUSION: The most reliable factors for predicting normal acetabular development after surgery were an acetabular index <25 degrees and a CHDD <6%. If the hips do not meet the criterion of a CHDD <6% after the osteotomy of one component (either the pelvic or femur) then the other component must be osteotomized.

"Diagnosis of Childhood Acetabular Dysplasia using Lateral Margin of the " Sourcil " / 대한정형외과학회잡지

In the treatment of DDH, generally we have used the acetabular index (AI) and the center-edge (CE) angle as diagnostic factors for hip dysplasia. However, it is sometimes difficult to mark the exact lateral edge of the acetabulum to measure these factors due to indistinct bony shadows on the image of the dysplastic hip. The purpose of this study was to evaluate the lateral edge of the acetabulum to determine the location of the most accurate marking point on the plain radiograph. Using plain radiograph, we studied 53 patients with DDH which were treated with closed reduction. 26 patients were studied using plain radiograph and another method: 16 patients with 3- DCT, 4 patients with MRI, and 6 patients with arthrograph. According to this study, the most lateral bony margin of the acetabular roof on the plain radiograph indicates the antero-lateral portion of the acetabulum. The lateral edge of the sourcil indicates the lateral margin of the centro-lateral (mid-superior) portion of the acetabulum. The marking point on the lateral end of the sourcil reflects a dysplastic condition of the acetabulum, especially in the mid-superior portion of the acetabulum.

Normal Acetabular Index in Korean Infant and Children / 대한정형외과학회잡지

The acetabular angles were measured in 2 groups of selected 100 infants and children each, of whom one group aged 14 months and younger and the other group aged 15 months of 5 yrs. and who were proved to be normal by all the physical examination and whose acetabular angles were below 40 according to Coleman's diagnostic criteria. The measurements were broken down into right and left, and male and female because of the known difference in the incidence of CDH in 2 members of each of these paired categories and analysed statistically. The following statistic significances resulted: l. All the measured normal acetabular angles vary between 10 and 31 degrees. 2. The acetabular angles decrease after weight bearing by the statistical significant difference between 0-14 mo. group and 15 mo-5yr. group. The angles are 22,61±3,47 (M±S,D) and 18.68±3.64 (M±S.D) respectively. 3. The acetabular angles of female of 15mo.-5yr. group are higher than male by the statistical significant difference. The angles are 17.77±3.54 (M±S.D) and 20.18±3.29 (M±S.D) respectively. 4. Statistical significant differences were absent between right and left.