Since the time one enters the realm of clinical medicine, the general area just inferior to the costal margins is introduced as the right and left hypochondriac regions (or, the right or the left hypochondrium). In the following discussion, I will confine myself to the example of the ‘right hypochondrium’.
As the years pass, in the course of medical education, one learns (rather, is taught) to say with increasing frequency, “pain in the right hypochondrium”; “mass in the right hypochondrium”; “tenderness in the right hypochondrium” until, the right hypochondrium gets so firmly ingrained in a student’s mind, as the part of the abdomen below the right costal margin.
Before we analyze further, a brief recollection of the various “regions” on the surface of the anterior abdominal wall may be in order.
The anterior abdominal wall is divided into 9 regions by drawing the
- two midclavicular (mid-inguinal) lines,
- the transpyloric line (plane),
- the intertubercular line (plane),
To call it a ‘Plane’, the line has to go all around the trunk.
The transpyloric line is drawn horizontally halfway between the jugular notch and the pubic symphysis.
The intertubercular line is drawn horizontally joining the tubercles of the iliac crests.
Midclavicular (mid-inguinal) lines, one on either side (self explanatory).
Try drawing these lines, or look up any text book of anatomy, and then identify the right hypochondrium. You will surely notice that there is hardly any right hypochondrium below the right costal margin! In individuals with wide costal angles, there may be small triangle of right hypochondrium below the costal margin; or, if one uses the subcostal line instead of the transpyloric line, you may be able to salvage a little more of right hypochondrium below the right costal margin. The subcostal line passes through the lowest parts of the costal margins (SC). It lies approximately at the level of the 3rd lumbar vertebra; in contrast to the transpyloric line which corresponds to the level of the lower border of the first lumbar vertebra.
It is surprising, that at times, the rules of anatomy are forgotten so soon. A student may even be failed in an anatomy examination for not knowing how to draw a transpyloric plane! It is surprising that this controversy is rarely, if ever, explained to the students and I have never personally come across any student who raised doubts about this aberration. This only goes to show how students tend to accept things they are taught without as much as a question (and worse still, teach ‘their’ students in the future).
It is understandable that certain concepts change or are discarded over time. My plea is that we should discuss with our anatomy colleagues regarding the rationale of continuing to use and teach certain anatomical landmarks/terminology in clinical medicine, (and even at times deciding the fate of an unfortunate student in an examination)!
Although it is of hardly any clinical significance, and has become acceptable, I felt that I should put it across. As for myself, it has taken decades to even realize that right hypochondrium is not in fact, the “right” hypochondrium!
CITE THIS ARTICLE:
M. Aroon Kamath, M.D.. The right hypochondrium… Is it really “right”? A territorial dispute. Doctors Lounge Website. Available at: http://www.doctorslounge.com/index.php/blogs/page/13346. Accessed December 18 2014.