Reimer or migration index
The migration percentage (MP) as described by Reimers is the gold standard method for assessing radiographs especially in children with hip dysplasia which quatitively shows how much femoral head has been dislocated from the ossified acetabular roof.The Reimer index is calculated as the ratio (alb) x100% where a is the distance measured the lateral border of the femoral head to the Ombredanne-Perkins line and b is the width of the femoral head parallel to Hilgenreiner's line. After the age of 5 years old when the cartilages in hip - especially the triradiate cartilage- are fused, the Reimer index in everyday clinical practise is usually described as the Femoral Extrusion Index.
The values are expressed in percentage % of the femoral head that is not covered by the acetabulum and the normal values vary according to the age of the patient. The advantage of this index is its independence of pelvic or thigh rotation and provides a good quantitative estimate of the degree of uncoverage of the femoral head. This cannot be estimated by a decrease in the CE angle of Wiberg.
The Reimer or migration index is to show how much femoral head has been dislocated from the ossified acetabular roof. After the age of 5 when the cartilages especially the triradiate are fused the Reimer index change his name and in everyday clinical practise and is usually described as the Femoral Extrusion Index. The values are expressed in percentage % of the femoral head that is not covered by the acetabulum and the normal values vary according to the age of the patient .
The Reimer index is calculated as the ratio (alb) x100% where a is the distance measured the lateral border of the femoral head to the Ombredanne-Perkins line and b is the width of the femoral head parallel to Hilgenreiner's line. The Reimer or migration index is to show how much femoral head has been dislocated from the ossified acetabular roof. After the age of 5 when the cartilages especially the triradiate are fused the Reimer index change his name and in everyday clinical practise
Various radiologic indexes have been used to detect hip displacement in children. The migration percentage (MP) as described by Reimers is the gold standard method for assessing radiographs especially in children with cerebral palsy in order to evaluate the risk of hip displacement and associated therapeutic interventions. The Reimer index is calculated as the ratio (alb) x100% where a is the distance measured the lateral border of the femoral head to the Ombredanne-Perkins line and b is t
The Reimer or migration index is to show how much femoral head has been dislocated from the ossified acetabular roof. After the age of 5 when the cartilages especially the triradiate are fused the Reimer index change his name and in everyday clinical practise and is usually described as the Femoral Extrusion Index. The values are expressed in percentage % of the femoral head that is not covered by the acetabulum and the normal values vary according to the age of the patient .
In a busy everyday practice measuring angles in X-rays in clinical settings it is time consuming and cumbersome. Accessory instruments like protractors, goniometers, well sharped pencils, rulers or even transparent papers must be available. Also after measurement you have to compare the data that you measure with the normal reference values according to patient age, and decide what could be considered normal or pathologic.
The Reimer Index app is medical software aimed for orthopaedic surgeons, providing tools that allow doctors to: -Securely import medical images directly from the camera or stored photos.
-Offers a very convenient way to determine the most accurate possibly way of measuring the percentage of femoral head which is not covered. By the aid of a circular transparent template which help to mark accurately the points of interest and the dynamic graphics who has been especially developed ,by clicking only two points the percentage is calculated. By inputting the age of the patient in the App, the measured values in percentage are compared with values from normal reference database accordingly. In cases the percentage of uncovered femoral head of the hip is beyond the normal range for the relevant age, the hips are categorised as borderline dysplastic or dysplastic ready to subluxate or subluxated ,dysplastic luxated or dislocated .
-Save the planned images, for later review or consultation. The software is a class II medical device in the FDA. All information received from the software output must be clinically reviewed regarding its plausibility before patient treatment! Reimer Index app is indicated for assisting healthcare professionals. Clinical judgment and experience are required to properly use the software. The software is not for primary image interpretation.
The app is a handy tool for an orthopaedic surgeon, radiologist, medical student or resident who wants objectively monitor and determine the severity of dysplasia of the hip. The build-in comparison feature with the normal reference values according to patient age may help decide what could be considered normal or borderline dysplastic or dysplastic and help also judge which hip is subluxate or at risk and help monitor objectively the treatment in time. The app is not a simple goniometer, is an enhanced product which offers the ability to compare all the input data with medical reference database. This feature it is particular useful especially in clinical settings where you need a quick results without losing time in looking for reference data in textbooks.
Reference
1.Reimers J. The stability of the hip in children. A radiological study of the results of muscle surgery in cerebral palsy. Acta Orthop Scand Suppl 1980; 184: 1-100
2.Li PL, Ganz R.Morphologic features of congenital acetabular dysplasia: one in six is retroverted. Clin Orthop Relat Res. 2003 Nov;(416):245-53
How to measure Reimer’s Index with the App. PLEASE see video below
Various radiologic indexes have been used to detect hip displacement in children. The migration percentage as described by Reimers is the gold standard method for assessing radiographs in children with hip dysplasia due to cerebral palsy or Down’s syndrome which describes the percentage of inadequate coverage of the Femoral head of hip and is useful to monitor and to evaluate the risk of hip displacement and associated therapeutic interventions. The reimer Index App offers an easy way of measuring the migration or extrusion index of femoral head instead of of using protractor and pencils and draw line and measure angles you have to mark few points on you iPad or iPhone screen.
The app , calculates and compares the measured data with known normal reference data and print in screen the values, the normal range and disclose which hip is dysplastic or subluxated or ready to subluxate. First you fill in the age of the patient in the empty boxes, age or months respectively then you have to select between right or left hip by highliting the relevant button - don’t forget in medical imaging by default what is left in the screen is right in reality, except it is otherwise by markings. After you have selected the side, the transparent circular template appears and you aim first to locate the center of the femoral head by moving the template over the femoral head, trying to fit to a best-fit circle to the contour of femoral head circumference. Once you have found the best fit by clicking the point button the center of the femoral head is marked (C1). Next a dynamic circle appears with the C1 center point marked over the screen. The radius of the circle is changed dynamically and by moving the attached finger you try to find the best fit circle to the contour of the femoral head circumference. Once you found the best fit you press the point button and the whole femoral head is marked by the circle. Next with the transparent circular template you try to locate the lateral acetabular border (C2 Point) and marked by pressing the point button.
The app calculates the Reimer’s or migration index or Femoral Extrusion Index. The values are expressed in percentage % of the femoral head that is not covered by the acetabulum and the values printed over the screen after being compared with the reference database according the age of the patient. The hips are cate-gorised as normal, borderline dysplastic, dysplastic ready to subluxate, dysplastic subluxated and dislocated. For the toddlers and children the Reimer’s reference database is included in the app. After the age of 5 years old when the cartilages in hip - especially the triradiate cartilage- are fused, the Reimer index in everyday clinical practise is usually described as the Femoral Extrusion Index. The values are expressed in percentage % of the femoral head that is not covered by the acetabulum and the normal values vary according to the age of the patient. The advantage of this index is its independence of pelvic or thigh rotation and provides a good quantitative estimate of the degree of uncoverage of the femoral head. This cannot be estimated by a decrease in the CE angle of Wiberg.
In a busy everyday practice measuring angles in X-rays in clinical settings it is time consuming and cumbersome. Accessory instruments like protractors, goniometers, well sharped pencils, rulers or even transparent papers must be available. Also after measurement you have to compare the data that you measure with the normal reference values according to patient age, and decide what could be considered normal or pathologic.
. By the aid of a circular transparent template which help to mark accurately the points of interest and the dynamic graphics who has been especially developed ,by clicking only two points the percentage is calculated. By inputting the age of the patient in the App, the measured values in percentage are compared with values from normal reference database accordingly. In cases the percentage of uncovered femoral head of the hip is beyond the normal range for the relevant age, the hips are categorised as borderline dysplastic or dysplastic ready to subluxate or subluxated ,dysplastic luxated or dislocated .
Reimer Index app is indicated for assisting healthcare professionals. The build-in comparison feature with the normal reference values according to patient age may help decide what could be considered normal or borderline dysplastic or dysplastic and help also judge which hip is subluxate or at risk and help monitor objectively the treatment in time. The app is not a simple goniometer, is an enhanced product which offers the ability to compare all the input data with medical reference database. This feature it is particular useful especially in clinical settings where you need a quick results without losing time in looking for reference data in textbooks.
see tutorial videos
ABOUT ORTHOPRACTIS APPS ORTHOPRACTIS CONTACT US
© Copyright Orthopractis.com 2020
