A Note on Discovering “New” Body Parts

We must always be careful with the idea of discovering a new part of the human body; it is not as if a Dua’s Layer magically appeared out of nowhere; it’s all of fifteen microns thick. We can expect the fourth of six corneal layers, then, to be difficult to find.

Likewise, we should be cautious in reacting to news that surgeons have discovered a ligament in the human knee.

Because, really, the question seems obvious:

Anterolateral ligament (ALL)Despite successful ACL repair surgery and rehabilitation, some patients with ACL-repaired knees continue to experience so-called ‘pivot shift’, or episodes where the knee ‘gives way’ during activity. For the last four years, orthopaedic surgeons Dr Steven Claes and Professor Dr Johan Bellemans have been conducting research into serious ACL injuries in an effort to find out why. Their starting point: an 1879 article by a French surgeon that postulated the existence of an additional ligament located on the anterior of the human knee.

That postulation turned out to be correct: the Belgian doctors are the first to provide a full anatomical description of the ligament after a broad cadaver study using macroscopic dissection techniques. Their research shows that the ligament, called the anterolateral ligament (ALL), was noted to be present in all but one of the 41 cadaveric knees studied. Subsequent research shows that pivot shift, the giving way of the knee in patients with an ACL tear, is caused by an injury in the ALL ligament.

‪Some of the researchers’ conclusions were recently published in the Journal of Anatomy. The Anatomical Society praised the research as “very refreshing” and commended the researchers for reminding the medical world that, despite the emergence of advanced technology, our knowledge of the basic anatomy of the human body is not yet exhaustive.

Even with all the caveats, it seems a strange proposition that it took 134 years to validate the original postulation.

So many medical students cutting cadavers. So many knee surgeries for athletes professional, amateur, and recreational. And yet here we are, breaking new ground in the twenty-first century.

It’s always been there, right?

Leuven, K. U. “Surgeons describe new ligament in the human knee.” ScienceDaily. 5 November, 2013. ScienceDaily.com. Retrieved 11 November, 2013.