The Incredible Human Hand!

I remember watching a couple of months ago, a documentary about the anatomy of the human hand. However I revisited the documentary not too long ago and I thought it would be great to post on here how extraordinary it was.

I must put it simply… it was truly fascinating! Never before on a television broadcast had a dissection been shown to the general public audience. It amazes me how the producers managed to obtain permission to do so. It just shows their passion for showing the world how remarkable the human body really is.

The programme was broadcasted by the BBC, this episode called Dissected: The Incredible Human Hand, presented by George McGavin.

The documentary can be seen here:



At the start of the programme, it was definitely a new experience for me when an arm was brought onto the dissection table. An unnamed person has donated this part of their body to medical science, and I appreciate that enormously as this programme did open my eyes a little more and enrich my learning experience.

Mr Donald Sammut, one of the worlds leading hand surgeons performed this dissection.



An incision was first made at the top of the forearm, and a skin "flap" was created in order to remove the integumentary layer and adipose (fat) tissue. Once this was done, the main muscles of the forearm could be seen. In association with these muscles, tendons are seen to be attached to each end of the muscle - and as I know from my biology classes, tendons transmit the forces of muscles onto bones.

At one point, Mr Sammut used his surgical instrument to tug on the tendon, which in turn caused the 5th digit (little finger) to be pulled upwards - almost if it were about to grip onto an object. I found this absolutely fascinating; a dead, motionless hand becoming animated once more.

How complex and intricate the very details of the internal structure are made me appreciate how we are able to carry out an infinitely diverse array of tasks with our hands.

Obviously you could see each tendon for each digit which also shows the very mechanical nature of our hands.

A tough protective layer was then removed which is located directly below the skin. This allows us to see the vital major structures and fine details such as the major artery and the major nerves.

The many muscles around our thumbs is quite extraordinary as it allows us to carry out a great multitude of tasks using various grips. Many ligaments hold in place a saddle joint made up of the thumb meta-carpel and the trapezium to minimise injury. This joint is in fact according to Mr Sammut one of the most likely to wear over time. What was most impressive to me in this section of the documentary was how the tendons are arranged in the hand. Moving towards the distal part of the hand from the wrist, the tendons are each encased in a sheath which offers protection. Quentin, the dissection assistant notes that this sheath, when removed allows the tendons to be seen in their 'pristine' condition. The deep tendon runs all the way to the most distal joint, and the superficial one splits part-way to attach to the one-but-most-distal joint. This to me is a marvel of biomechanics.

According to Quentin, the nerves are "probably the most difficult part in the hand to dissect, but it also makes them the most exciting". It's truly amazing how every part of the hand, every tissue in fact is supplied with a nervous network. At the fingertips alone, 20,000 nerves terminate at each finger to allow for as much sensory information to be obtained from the environment.

Overall, what was most surprising is that if we were to lose one finger by choice, the index finger would be the one we could 'most do without'. In the words of Mr Donald Sammut:

"Although it is included in everything [you] do, you can exclude it from everything you do."

I highly recommend anyone to watch this documentary, even if it is just for appreciation!

Feel free to leave a comment below, I'd be interested to hear what you thought about that dissection!