Hip dysplasia App
Hip dysplasia leads to premature osteoarthritis of the hip and accounts for many of total hip replacements in patients. The early diagnosis is extremely important and is based mainly on the radiological findings. In a radiographs correctly performed measurements of Indexes like the Acetabular Index (AI), the Center-Edge (CE), the Acetabular Depth-Width Ratio (ADR), the femoral head extrusion index or Reimer Index (RI), the Congruity Index (CI), the Sharp’s angle (SA), Tonnis grade of dislocation (TG), the Acetabular Index of the Weight-Bearing Zone (AIW) or Horizontal Toit externe angle (HTE), and Congruence Index (CG) are important for an the orthopaedic surgeon who wants objectively to asses and monitor optimally on standard radiographs the hips. These measurements usually performed in one X-ray by the traditional way which is time-consuming and cumbersome.
We offer this new app, in which simply by marking five points at each hip you measure in an instant, all these indexes. The app also compares the results with normal age, gender and side specific reference databases retrieved from the international literature.
The Hip dysplasia 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 nine Indexes of hip dysplasia at once. By inserting the gender the age and marking five points at the same X-ray, at each hip, the App calculates the nine above mentioned indexes (AI, AIWB, CE, RI, ADR ,CI, SA,TG, CG) without to have to repeat each measurement separately. You measure all radiographic Indexes in one picture. Gender age and side-specific normal reference databases are used and in cases where values are out of normal ranges, the hips are categorized according the measured Index normal categorization.
-Save the planned images, the measured values and results compared by normal reference databases, for later review or consultation.
-The app also is independent from errors produced by image inclination. Especially developed module allows the user to measure accurately without to worry about the tilting of the picture or the X-ray.
All information received from the software output must be clinically reviewed regarding its plausibility before patient treatment! Hip dysplasia App indicated for assisting healthcare professionals. Clinical judgment and experience are required to properly use the software. The software is not for primary image interpretation.
In a busy everyday practice, measuring in X-rays in clinical settings it is time consuming and cumbersome. Accessory instruments like protractors, goniometers, well sharp pencils, rulers or even transparent papers must be available. In case you have a packs system usually you don’t have the reference data. The app offers a very convenient and also accurate way to perform most common radiographic measurements for hip dysplasia, in a blink of an eye in front of your I-phones screen. The build in feature of the app, allows results to be compared and categorized according to gender, age and side-specific normal reference databases and may help decide what could be considered normal or pathologic.
The app is not a simple goniometer, is an enhanced product which helps to monitor objectively the course of the treatment and evaluate optimally the remodeling of the hip. This App is particular useful especially in clinical settings where you need a quick results without losing time. Please see tutorial videos at the developer’s web site.
1.Wiberg G. The anatomy and roentgenographic appearance of a normal hip joint. Acta Chir Scand. 1939;83:7-38
2 .Tönnis D. Normal values of the hip joint for the evaluationX-rays in children and adults. Clin Orthop Relat Res 1976; (119):39-47
3. Novais EN1, Pan Z, Autruong PT, Meyers ML, Chang FM.Normal Percentile Reference Curves and Correlation of Acetabular Index and Acetabular Depth Ratio in Children. J Pediatr Orthop. 2016 Jun 2. [Epub ahead of print]
4.Murphy SB, Ganz R, Muller ME: The prognosis of untreated dysplasia of the hip: A study of radio-graphic factors that predict the outcome. J BoneJoint Surg 77A:985–989, 1995
5.Delaunay S, Dussault RG, Kaplan PA, Alford BA Review Radiographic measurements of dysplastic adult hips Radiographic measurements of dysplastic adult hips. Skeletal Radiol. 1997 Feb;26(2):75-81.
6.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
7.Sharp IK. Acetabular dysplasia. The acetabular angle. J Bone Joint Surg Br 1961; 43B:268–272.
How to measure with the Hip dysplasia App
The app offers a very convenient way to asses Hip Dysplasia by measuring the following ,The Acetabular Index (AI) the Center-Edge (CE), the acetabular depth-width ratio (ADR), the femoral head extrusion index or Reimer Index (RI), the Congruity Index (CI) , the Sharp’s angle (SA) and the Tonnis grade of dislocation (TG) based at the Tonnis classification, Acetabular Index of the Weight-Bearing Zone (AIWB) or Horizontal toit externe angle (HTE), and Congruence Index (CGI).
The first thing is to load one image from your photo library or capture a photo from x-rays photos of a patient.
Measurements by default are starting by the right side and choosing in orderly manner certain points of the hip sequentially are important for proper measurements. By starting first of or the right hip ,the he transparent circular template -Moses template- that consisted of several concentric circles appears. First you aim 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 find the best-fitted circle superimposed over the femoral head then you click the button ‘point’ and the center of the femoral head is marked and the first point of measurement is marked (P1). Next a dynamic red circle appears with the P1 center point marked over the screen. The radius of the circle is changed dynamically and by moving the attached finger, you try again 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 blue circle (P2). Next you aim at lateral acetabular border and by pressing the ‘point ‘ option you mark the P3 point. Next by the same manner you aim at the juncture of the triradiate cartilage of the acetabulum and you mark the P4 point. In case the patient is over 7years of age the triradiate acetabular cartilage is ossified and you have to choose the most medial edge of the weight bearing surface of the acetabulum.The Weight-bearing portion of the acetabulum is recognised by its sclerotic, arched appearance, resembling an eyebrow (sourcil). After that you aim at the last point the tear drop of the acetabulum and by pressing again the ‘point’ option you mark the P5 point.
For the left hip , by repeating the same task you locate with the same above mentioned manner, in orderly sequentially way.The procedure start over again with the same manner over the left hip this time
In quick view , the points you have to choose sequentially in each hip, are shown below by the following order:
P1 —> femoral head center
P2 —> dynamic cycle -radius of femoral head
P3 —> lateral acetabular margin of acetabulum
P4.—- > triradiate acetabular juncture, if patient over 7 year of age medial edge of the weight bearing surface of the acetabulum.
P5. —-> tear drop of acetabulum
P6 —> femoral head center
P7 —> dynamic cycle- radius of femoral head
P8 —> lateral acetabular margin of acetabulum
P9. —>triradiate acetabular juncture, if patient over 7 year of age medial edge of the weight bearing surface of the acetabulum.
P10. tear drop of acetabulum