The differentation of direct (or medial) and indirect (or lateral) hernia is important, in oredre to get a tailored approach to the disease: For a direct hernia an onlay prosthetic rapair, for an indirect hernia a 3D mesh repair.

I agree with you, but i think this differentiation is more accurate intraoperatively

Yes & No. Yes, as long as one is a resident in training for the ability to differentiate & discuss the difference is an indicator of anatomical understanding & hence the ability to plan surgical approach & surgical navigation.

No, for a surgeon proficient in TEP as not only TEP will truly display the laterality or otherwise of the culprit ring but also allow complete, adequate & appropriate prosthetic coverage of the entire myopectineal orifice of Fruv=chhard. But than, the proficiency in TEP would follow an understanding the anatomy & diffentiation of the types of hernia mentioned.

In my opinion as the management of inguinal hernias have been to a great extent rationalized apart from a point of historical interest and to confuse undergrad students there is little role left in clinical tests differentiating the direct from indirect inguinal hernias.

For a laparoscopic surgeon, I think there is no need to differentiate

At clinical examination is impossible to differentiate a direct ( medial) from a Indirect (lateral) hernia....We can find some papers in the literature about this......We can supppose only that  bilateral hernias are probably medial....In my opinion we can get a correct diagnosis only intraoparatively.

Thank for the interesting question, Dr.Alawad,

This very question is one of the favourites for my students to ask me about. I am agreed with Dr.Agarwal about his formula "Yes AND No", but not entirely.

When a groin hernia is well-developed, its presentation is usually typical and clear as well, so, having performed a well-known and easy set of clinical examination of a given patient (both in vertical and supine position), a surgeon acquired sufficient information about a kind of the hernia, direct or indirect (oblique), etc. I would not repeat the appropriate clinical diagnostic algorithm here. It is depicted in every textbook on Surgery. Indeed, the diagnosis obtained by clinical examination will be preliminary and demand verification during the future operation in terms to exclude, for example, a relative weakness of the posterior wall (the transversal fascia) in case of oblique hernia, or in so called ‘pantaloon hernia’ having both sacks, direct and indirect. On the other hand, the former is rather speculative and, to the best of my knowledge, has not been reinforced by reliable evidences yet; the latter is casuistic and occupies just a tiny part of consecutive hernia repair amount.

In my humble opinion, a certain difficulty may appear as to the differentiation between a putative hernia and other lumps in the groin region when the former is presented as a small and irreponible swollen. In that case, the ultrasound investigation is indicated. Another difficulty may be presented by, so to say, ‘just history hernia’ when a patient declares that a lump occurs from time to time, but there is nothing can be detected either in the course of routine clinical examination, or during provocative tests. I recommend in that case to perform ultrasound also, and to take a second look in a while.

However, I dare to believe that the question may be a little deeper. An educational strategy that takes over the center of weight in terms of diagnostics from the pre-operational to intra-operational time and abolish clinical examination of the groin region before operation may raise certain concerns. The duration of operation is limited (that of clinical examination is not) and the fewer would be surprises on elective surgical procedure the better. On the other hand, university education supposes to include a variety of disciplines, from Chemistry and Biology to Philosophy and Sociology, so it would be strange enough to suggest a Procrustean bed for not else, but for the learning of clinical examination.

A physician who cannot examine the inguinal region and does not possess the ability itself to distinguish between the direct and indirect hernia before operation, would hardly be able to find out a difference between the inguinal and femoral hernia. Furthermore, that physician would discover none of the obturator hernia before operation or autopsy. That physician would not differentiate the femoral hernia from the femoral artery pseudoaneurism or other vascular abnormality.

The direct and oblique hernias have got seemingly quite different pathogenesis. So, the oblique hernia does not demand a mesh insertion in each case, but the direct does without any doubt. The direct groin hernia (usually bilateral, but not exclusively) may become the first clinical manifestation of the Marfan syndrome in the children and teenagers on medical screening (the indirect does not) (for example, see PMID:1855754, and many others).

As for the maxima "At clinical examination is impossible to differentiate a direct from an indirect hernia" it needs evidence. I truly hope that Dr.Negro would be so kind as to share aforementioned papers with us.

Sorry for being too long and boring.

Sincerely,

Thank you Andrey for your Academic Lecture.

Anyway I'd like to say something about the question.

1) About 20/25 years ago a paper from Shouldice Hospital argued that "At clinical examination is impossible to differentiate a direct from an indirect hernia"

2) This is not always true. A large inguinal hernia that slips in the scrotum is almost always indirect.

3) Almost always, but not always, a contemporary bilateral inguinal bulge is suggestive for a double direct hernia

4) I operated on in emergency setting some strangled hernias in older people of male gender that surprised me because I found femoral hernias and not inguinal hernias like I had previous supposed

5) In the time that we are living I think that the preoperative diagnosis of a inguinal hernia represents a little issue especially for laparoscopic approach.

Giorgio Vasquez

Dear Dr.Vasquez,

It is pleasure always to read the profound, elegant posts of yours.

However, I should notice that the question is "Clinical differentiation of direct and indirect inguinal hernias: is it worthwhile...[still for] teaching medical students?" So, the question is about the education of future surgeons, not practising.

Every grown-up surgeon has elaborated at last, after years, his/her own ways and style of diagnostics; history taking (up to precise verbal formulas); decision making; operating; and so on. How and why he/she makes this or that in this or that way, he/she can not explain sometimes even to him/herself. All these are the results of his/her long proffesional evolution. The surgeon's cllinical examination quality is not equal to the student's one, it is evident enough. So the student should not copy the grown-up surgeon's ways blindly, he just could imitate, but could not repeat it.

I believe that medical students should be taught in the comprehensive, academic way in general and in particular. There are classical approaches have been developed from the 18th century or even earlier: to use every possibility and every stage of contact with a patient for diagnostics. So that to not avoid any possibility to make the correct diagnosis before, during, and even after operation. When (and if) a student will become a surgeon, he/she chooses him/herself what is surplus and what is really needed from the knowledge acquired during education for his/her own practice and life. Of importance, I bet that his/her perception of the neediness or needless of various methods' value will keep changing on as he/she is living.

Concerning the inguinal hernia properly: I would love to read that article from Shouldice Hospital were I have got something more definite than a phrase from it. For now (I may change my mind after reading), I think that that very phrase is not else, but a polemic exaggeration even for clinical practice. I would rather tell that 'It is not always wrong".

Doubts in classics are not seemingly for the beginners. Must know and have own experience first, then doubt, not vice versa. Polemical issue is rather a warning for those who is becoming too self-confident in Surgery.

On the other hand, I am ready to participate in an evidence-based metaanalysis or questionnaire development concerning value of the routine herniological examination of the groin region.

My dear Andey,

Thank you for your comprehensive reply, which I really appreciated.

No one can dispute the fact that the hernia chapter  is a real headache for the students, from the anatomy of the inguinal canal to reach the descriptions of the different types of hernia: inguinal, direct / indirect, femoral hernia, and rare hernias. This teaching must be academic, but given the complexity and articulation of the surgical anatomy, my experience is that this subject is taught and badly. If you want to fail a student of medicine in the course of an examination, ask the anatomy of the inguinal canal. Only recently on strong indication of the schools of surgery we obtained that  lessons of hernia surgical anatomy, a professor of anatomy participate. The result was not very different. The hernia for the young surgeon remains a mystery, from anatomy and pathophysiology to surgical treatment. Only with the frequency of the operating room and assisting a surgeon skilled in hernia pathology, the young surgeon begins to muove first steps through a not simple and not short pathway. Moreover, Professor Bassini was nominated for the Nobel Prize for his work on 'hernia, an award that was later awarded to Theodor Kocher for her thyroid surgery.

Now distinguish clinically between direct and indirect hernia is not impossible, but it must be taught by a tutor who has specific experience on the subject. More difficult is the diagnosis of femoral hernia, certainly more rare but  more dangerous  in the behavior.

Excuse me if I have dwelt, and if I went off with the theme of the application, but this is my personal experience.

Best regards,

George Vasquez

Thank you very much, Dr.Vasquez,

May I share my personal intellectual property here?

A theme 'Hernia' takes 12 academic hours in the 4th year students' schedule at our University. I begin lessons with short questions, seemingly plain and even childish. For example:

What is the aim for the inguinal channel to develop during the evolution?

Or the femoral one?

Do other animals have these anatomical structure?

The fish?

The frog?

The crocodile?

The turtle?

The bird?

The kangaroo?

etc.

(adapted for medical students after Kardong KV. Vertebrates. Comparative anatomy, Function, Evolution. 5th ed., McGraw-Hill, 2009)

A comparative anatomy etude leads to the surgical embryology (mainly after JE.Skandalakis et al. The embryology of the inguinofemoral area. Hernia 1997; 1:45-54, a little simplified).

___________

At second:

Some words introducing into Sphincterology concerning the general pattern of various sphincters anatomical structure and relationships:

1) oblique implantation of the oesophagus into the stomach;

2) oblique implantation of the common bile duct into the duodenal wall;

3) oblique implantation of the ureters into the urine bladder wall;

4) oblique course of the cord through the abdominal wall

5) why has this general rule been developed?

(from Kolesnikov LL. The Sphincterology. Moscow, GEOTAR-Press, 2008).

At thirst:

A simple task on Physics:

Given: a thin-walled rubber ball under the high inner pressure.

Question: How to place a tube for the measurement of its inner pressure in its wall in that way so that the tube would not be pulled out by inner the pressure

(See the 2nd attachment)

As far as I know, some scholars are afraid of the matter complexity. I believe that it is scholastics and absence of the logical chain what should be afraid of. My students dig the business soon and well to the end of the first lesson.

So, the next picture is following which outlined the outer patterns of hernias in the groin area: indirect (putatively developed due to some degree of the processus vaginalis retainment); direct inguinal and (direct) femoral. So, the indirect inguinal hernia is unique in terms that it is the only hernia in the groin which has had the oblique course and oval outlines. The remain hernias have had direct channel and roundish outlines. The indirect hernia always begins from the acute angle of the medial side of the deeper inguinal ring. This very place a surgeon should seek for the hernia at.

The IH with direct channel has been developed due to destruction of the transversal fascia of this angle pulling vv.epigastricae inf. medially.

There may be exceptions in real clinical practice, but it is the basic knowledge to start with.

Thank you for attention

Here is below a well-written monograph, perhaps remained unknown to Western readership:

Kukudjanov NI. Pakhovye gryzhi [The Inguinal Hernia]. Moscow, 1949, 440 pages, 156 figures.

Dear Professor,

Thank You for the interesting links. Unfortunately I'm not able to open the monograph.

Anyway thanks a lot for your precious suggestions.

Giorgio Vasquez

Thank you for this interest!

It is a .djvu file. It can be opened by several free programmes, for example, WinDjView. You will find it in the Internet.

Just for example, several pictures from the monograph:

Thanks for the suggestion.

Giorgio Vasquez

I started remembering my student days when we used to struggle to decide whether the hernia is direct or indirect.But presently it is not relevant because we advice surgery whether it is direct or indirect.From pt point of view indirect hernias may obstruct/srangulate.From surgeons point of view LHR for indirect hernia takes longer time.

Very Interesting comments Dr Borodach. I will be able to use it in my teaching. 

I am sorry I a bit different from Dr Reddy. I still believe it is essential to differentiate between a direct and indirect, even though the treatment is the same. One it is a good technical exercise. But more importantly if an elderly person with lot of co-morbidities (as a significant majority now have) comes with a direct inguinal reducible inguinal hernia, I reassure them that they can easily live without having an operation unless it is very uncomfortable or patient is very keen to have it repaired, in which case I will repair it under LA in my Walk in Walk Out Hernia clinic. 

However if they present with Indirect inguinal hernia, which carries a risk of strangulation, I rather repair it electively under LA if possible, than wait for it to become bigger (inguinoscrotal) or gets strangulated when one has no choice but to operate under GA.

Dr.Bhutani,

Thank you for the comment. I have been about to think about a voice crying in the wilderness. It is a good point about the elder patients with co-morbidities that did not come to my mind. However, one should notice that the direct hernia does not guarantee from a strangulation in every case.

Actually, everything is not said about the hernia. For example, of the strangulation mechanims. The famous surgeon and researcher Th.Kocher, the future Noble laureate, used to investigate mechanisms of various types of incarcerations experimentally. He could not reproduce the Richter type (partial) and called it as 'the most intriguing riddle. Indeed, if a soft and gentle loop of the small intestine can introduce itself into a small opening with rigid, non-elastic edge to become strangulated, so that the copulative disfunction is just idle talk.

Moreover, there are not any reliable bacteriological data about the hernial sac's content in the incarcetation either in clinic, or in experiment which impairs any evidence-based guidelines concerning the mesh reconstruction in the conditions of incarceration. And so on, see the links below.

Sincerely,

Andrey

https://www.researchgate.net/post/What_are_the_current_views_on_Richters_hernia

https://www.researchgate.net/post/Is_there_any_data_on_a_correlation_between_visual_Cruse_criteria_and_the_bacterial_count_of_hernial_sac_fluide_for_incarcerated_strangulated_hernia

https://www.researchgate.net/post/Do_you_perform_mesh_based_reconstruction_of_abdominal_wall_hernias_with_incarcerated_bowel

It is not really important to classify the inguinal hernia for planning the type of treatment to be given.This is especially so in our mesh free and tension free repair. We will recommend mesh free and tension free open repair in all cases to avoid dangers of a foreign body. Pl. visit www.desarda.com

Dear Dr.Desarda,

Do you recommend open repair in ALL cases, including bilateral and recurrent hernias?  There is no role of laparoscopy here?

I think there is NO need to clinically differentiate between direct & indirect hernias.  Either way, the repair technique is the same

Good discussion,remembering my fellowship days ,during the primary FRCS course we were informed that any mistake as for as hernia is concerned NOT ACCEPTABLE,which means the candidate has to face the exam again.Last month when I was examining Minimal access surgery candidates co examiners were asking about direct or indirect Hernias.After listening I feel that students must be taught to differentiate.It is important for MIS surgeon also to differentiate as planning OR timing, costs and any post operative problems like scrotal swelling,pain can be discussed and planned.As surgeons we know surgery is full of surprises that makes us to keep one step ahead of others.

A through critical analysis of the inguinal hernia classification in to direct and indirect hernias is impressive and enlightening . It is the Hasselbach who recommended this classification of inguinal hernias in to direct and indirect hernias on the basis of the relationship of the sac to inferior epigastric vessels. The classical teaching had been to repair the indirect inguinal hernias on the basis of likely future complications if left untreated even though at the time of presentation they do not cause any symptoms other than the bulge. The trend had slowly shifted to watchful observation especially for asymptomatic hernia ( considering that simple groin bulge is not a symptom) when specified conditions are fulfilled and is an acceptable option. We now know that even the direct inguinal hernias can strangulate if they are of " funicular or diverticular variety" ( i.e., the hernia can protrude through the rupture in transeversalis fascia unlike the more common ones that bulge through attenuated transeversalis fascia. There is no way either clinically or imageolgically to differentiate between the two. Further , such funicular or diverticular type of direct inguinal hernias can descend in to the scrotum). This could be one justification for subjecting the patients with clinically or imageologically confirmed direct inguinal hernias to surgery on par with the indirect inguinal hernias. The other pitfall in the diagnosis of the indirect inguinal hernia is the ambiguity of the surface marking of the internal inguinal ring, which is described in the literature as " mid inguinal point" " mid point of inguinal ligment" and finally as per the department of anatomy Manipal as " mid inguinal region"

I’m not sure it makes much difference really. Potentially if the patient is inclined to manage conservatively , it might be worth differentiating purely because conventional teaching suggested indirect have a higher chance of complications. Marginal though

Sermons rate is higher with direct alone herniae than indirect but majority that I see as direct are in fact Pataloon

@I am also teaching to my UGs and PGs and want to have really the research over that , are the clinical tests , ring occlusion and ring invagination tests can differentiate the direct or indirect hernias . Is these test having any clinical significance ? ..... After 4-5 months of clinical testings of inguinal hernias ,

I concluded that in large hernias and pantaloon hernias we would not be able to differentiate direct and indirect hernias clinically by these test . It is only by the intraoperative findings we can be made the diagnosis of direct and indirect hernias .

Hi Priynka

I am afraid it did not need 4-5 months of testing to realise that Irreducible herniae one cannot say that they are Direct or indirect, but significant majority would be indirect. Pantaloon hernia basically means that patient has a hernia with both direct and indirect component. I am sorry I am not able to understand what was your testing about. Please advise me so I may learn something.

This was just the clinical and intraoperative correlation .

Now we are adding the Zeeman test and occluding the superficial inguinal ring to differtiate the direct and indirect inguinal hernia even in pantaloons hernias .