Guidelines for instructors

R.Graf

S.Scott

Tips, Tricks, common mistakes

The base for the trainig course is the Manual:

Essentials of infant hip sonography according to GRAF

Edition Stolzalpe ,Sonocenter,2016

A-8852 Stolzalpe

Internet:

Introduction: The contempt of this paper gives only additional comments and tricks for the trainers.It is recommended to go ahead in the courses chapter for chapter from the Manual.

 

 

1. Start with the 3 Pillars of hip sonography: A/B/C

Comments:

*Explain why the anatomical idendificatio(A) is so important: German quality comission: In 48% wrong diagnosis because of wrong anat. identifcation! Tip: Ask now: "What anatomical structures are hyalin cart.preformed on the prox.fem.end"?---f.haed,trochanter,but the prox. part of the fem.neck is forgotten normally. (This question "keeps down" med. doctors,who know everything ?!?)

*Most important is the examination technique,--good technique solves the problem of A and B. (No experience and no skill is necessary for the ex.tech.,takes 1 minute (!) with a a special technique and equipment)

1.2 Fem.Haed. Point out:

* anular zone is not fluid

* because the fem.haed is not round,all measurement systems,which are  working with " 50%, more or less haed covering" are not more than eye bowling.

1.4 Joint capsule.Point out the common mistakes:

* Capsule is mixed up with the intermuscular septum (mainly in decentred joints)

*ischiofemoral lig. shoud not be misinterpreted as a "ruptured labrum".

1.6. Bony rim definition.

* Explain,that the bony rim is the lateralst point of the sound shadow and how the sound shadow comes up.(see Fig in the Manual)

* Explain,that the sono must not be used,when even 1 of the structures of checklist I is not visible!! If all the stuctures are identified,you are always on the "safe side"!  (Tilting effects and wrong anatomical identification are excluded)

2.Usability check,Checklist II.

2.1 Tip:  *Demonstrate with a sheet as a plane on your hip joint,why it is important that the plane is in the middle of the acetabulum,marked by the lower limb.

               * Make a drawing of the with a view in the acetabulum with the 3 bones and the lower limb and a sono          with the l.limb also,to demonstrate the importance of the lower limb.

                  

2.2 Tip:   *Demonstrate on your body the rotation of the pelvis during   the human evolution and where the good bony coverage is today because of the rotation,see Fig.

              

2.3 Tip: * Demonstrate with a sheet the tilting of the plane                                                                                                 * point out the typical mistakes (1/2/3) of labral misinterpretion.

 

 

 

 

3.Types

3.1 Point out: Never use the terms "healthy" or "normal"! Healthy or normal depends from the age.Use for Typ I "mature"!!!! (Type IIa is "normal " and "healthy" also!)

3.3/3.4  Point out,that the problem is not the labrum, it is the deformed hyalin.cartl.roof.The perichondrium is fixed on the cart.roof and shows indirectly wether the cartl. is pressed:  up- or downwards. The difference,type III or IV is not made by the labrum! (common mistake by "experienced delegates").

Important now: Explain now the exception from the usability check and why in decentered joints the lower limb may be not visible.(Different planes! Typical wrong answers: 1. Nucleus is blocking the beam.2.Chondrooss.border is blocking!) Checklist I first(!),because if you see according the  anatom.identification a decentred joint,---- it may be not in the plane,no measurement !!!!!!

 

Practical Session:

After the theoretical part ( Checklist I/ II and types) start with all delegates in the hall:

1. Anatomical identification: Train checklist I first. Give a pointer in the group "randomisized", not one by one! (Everybody is stressed and attentioned,because nobody knows,who is the next "victim".)

2. Demonstrate Type I -IV: Train the checklists and typing by eyebowling.

4.Standards of Reporting

Explain

 * why 2 sonos in the standard plane.( Tomogram, not a "plane",it is a "standardsector",because of the  beam club.(2    are the minimum of a tomogram)

 * Lines are sometimes covering important echoes, 1 sono with and 1 without lines makes it more precise.

5. Description:

 *  is only eye bowling to train the estimation of the covering and the anatomical structures,final diagnosis is made always by measurement. Descrepancies between description and measurement forces to check the sono again. Explain-- more than the half (50% ?) or less is only eyebowling.

6.Measurement

6.1 Hints to avoid typical mistakes:

 * Bony roof  line (BRL) never inside the echoes!

 * BRL in contact to the "bone" and not to the bony rim !

 * BRL comes from the lower l. and not from the middle of the lower limb.

 * The lines are normally not crossing in 1 point. (Rarity, in Type I only , but seldom)

 *Explain the different echoes on the lower l.: Sinus,fat,ligament.

Important hint : Explain, why this meas.system is the best from 22 systems,which had been checked by computers and is working more than 3o years:

1.The sytem is independent from the size ,deformations and the position of the haed.

2. No line is the base for the next line: If a mistake is done in one line,this mistake is not the base for the next line.( The mistake is still there, but not "exploding")   It makes the measurement safe and the diagnosis is not acc.the angles directly,it is acc. the type! So inter-/intraobserver variation does not matter.

7. Differentiation of Types/Sonometer

7.1.1 "Translate" type IIc: haevy dysplastic joint,needs treatment in any way.

7.2.1  Explain the difference in Type Ia/b: "blond or black hair" (today) and the hypothesis about pincer impingement and labral tears.(future)

8.Elastic wipping/instability.

* Explain,why the cart.roof and labrum goes up and down alway, even in "normal" joints (haed is not round,jont capsul laxity) It is necessary to seperate this harmless from the dangereous movements by measurement.

* hip sonography is always dynamicly (tomogram!), but to make it reproducable a standard plane is necessary.Additional  only in borderline cases (Typ IIc), a "stresstest" is needed. (misinterpretation of "dynamic" and "static" examination!)

* A stresstest makes only sence in type IIc to decide "stable or unstable".Not in decentred or TypeI/IIa/IIb.---It aches the baby!

9.Examination technique.

Hints:

* Explain way in this way,( +/- lists)

* Handling the mother/ positioning the baby/ handposition of the mother.Never pullon the leg,explain why it aches!!!

* Intermezzo: Gel on the skin/ Fingerposition

* Forward-backwards..... and pickup the lower limb first,never the plane first!

1o.Tilting errors.

Explain: Different speed of the ultrasound in the muscles/cart./bone of the babies: Different speed makes bowing etc of the beam and different pictures.

Linear probes only, no sector- or trapezoid probes!

11.Projection.

Explain, that the standing upright projection of the hip joints (like in an X-ray) is the best by evidence,horizontal with cranial left the worst.(No evidence,only tradition!) If standig upright not possible,than horizontal but cranial right,which is the next best.

12. Tips for practical session:

* Measurement trainig: Each delegate gets only 1 sono.If he comes back,don`t explain a mistake immediately,give him a hint only,that he has the chance to find the mistake. If he could not find,the collegue should help; only if both had not solved the problem,--explain!

* Don`t explain mistakes for the whole group: everybody should make mistakes for his own.

* Only 1 sono for each, if possible. it is better than 4 on a sheet. One per one gives more personal contact with the trainer-- and more questions.