Hands and Feet: Tarsals

The tarsalsSeven ankle bones forming the hindfoot and midfoot. are a feat of architecture. They have a weight-supporting arch. The instep proves hard to fit when knitting socks.

Tarsals are the bones of the ankle.  There are seven tarsals, but they are not aligned into rows like the carpalsEight small wrist bones arranged in two rows; allow wrist flexibility. claim to be. It is useful to start with 3 bones that all have the same name: cuneiform. I had to look that one up.  It means hieroglyphics. The three cuneiform bones are the medialToward the midline of the body, intermediate, and lateralAway from the midline of the body..  In that order they articulate with metatarsal #1, #2, and #3. Sometimes students get mixed up and call the intermedial cuneiform the medial.  Remember that intermediate means “between” and medial means “to the middle.”  It’s a subtle but significant difference.

First and foremost with the foot, you want to identify if you have a left or a right. This is easily done via identification of the “big toe” or the 1st digit. Many of the tarsals articulate with specific metatarsalsLong bones of the foot; numbered big toe (1) to pinky toe (5).. This is a useful way to identify the tarsals. As with any group of bones, you should designate 1 or 2 bones that you just know without question. Then, know how the other bones relate to those 1 or 2.

Also a name starting with C is the cuboidCube-shaped bone on lateral side of foot in front of calcaneus. bone. It articulates with the metatarsals of digits #4 and #5. These 4 bones are easily identified with their names all beginning with C and their articulation with the metatarsals.

Knowing the 4 bones that articulate with the metatarsals leaves only 3 tarsals left to identify. Luckily, the navicularBoat-shaped bone in front of talus; medial side of foot. bone articulates with all 3 of the cuneiform bones on its anteriorThe front of the body or toward the front when standing in the anatomical position. face. On the posterior face, it articulates with a bone called the talusAnkle bone that articulates with tibia and fibula; sits atop calcaneus..

I had taken a geology course before taking anatomyThe study of the structure of the human body. and physiologyThe study of how the body functions.. I knew that the word talus is the rock and debris that falls down a mountain. It collects at the baseA substance that accepts hydrogen ions (H⁺) or releases hydroxide ions (OH⁻)..  You’ve seen rock formations like this on the side of the road.  The talus bone is the base of Leg Mountain.  The talus is the bone on which the tibiaShinbone; large, weight-bearing medial bone of the lower leg. sits.  There are fractures called Pott’s fractures, where the tibia and talus disconnect.  Horrid. 

Lastly, we have heel bone, which is larger and more strangely shaped than you think. The calcaneusHeel bone; largest tarsal; attachment site for Achilles tendon. or heel bone is not just the back of your heel. It sits under the talus as well.  Look at the extent of this bone on medial pictures, not superiorAbove or toward the upper part of the body. view pictures.  The calcaneus is underneath this bone here called the talus. 

The medial cuneiformMost medial of the three cuneiform bones; articulates with first metatarsal. articulates with the metatarsal (foot, not ankle, bone) of the 1st digit or the big toe.  Once you identify the medial cuneiform, you can move laterally to name the other two.  This last bone here is often times forgotten by students.  I don’t know why, they just forget.  It’s the cuboid bone and it articulates with the 5th metatarsal.