Difference Between Tarsal and Carpal Bones

The key difference between tarsal and carpal bones is that tarsal bones are a cluster of seven bones present in the foot while carpal bones are the eight small bones that connect our hand into the forearm.

Wrist and ankle are important parts of the human skeleton. Wrist or carpus contains eight carpal bones. These carpal bones connect hand and forearm. Our foot consists of 26 bones. Ankle or tarsus contains seven articulating tarsal bones. They are situated between the lower end of tibia and fibula of the lower leg and the metatarsus.

1. Overview and Key Difference
2. What are Tarsal Bones
3. What are Carpal Bones
4. Similarities Between Tarsal and Carpal Bones
5. Side by Side Comparison – Tarsal vs. Carpal Bones in Tabular Form
6. Summary

What are Tarsal Bones?

Tarsus or ankle joint consists of seven tarsal bones. They are the talus, calcaneus, cuboid, navicular and three cuneiforms. Talus and calcaneus are in the hindfoot while cuboid and cuneiforms are in the midfoot. The navicular bone is an intermediate bone located between the two above groups. Talus is the most superior bone resting on the top of the calcaneus.

Difference Between Tarsal and Carpal Bones

Figure 01: Tarsal Bones

Calcaneus, also known as heel bone, is the largest and strongest bone in humans. It acts as the weight-bearing bone within the heel of the foot. Navicular bone resembles a small boat while cuneiform bones are wedge-shaped. Tarsal bones are situated between the lower end of tibia and fibula of the lower leg and the metatarsus.

What are Carpal Bones?

Carpal bones are the eight small angular bones that make the human wrist. They are arranged in two rows of four bones: the proximal row and the distal row. Scaphoid, lunate, triangular, and pisiform bones form a row towards the forearm. The other four bones – trapezium, trapezoid, capitate, and hamate – form a row towards the fingers. Moreover, each carpal bone has six phases as superior, inferior, medial, lateral, anterior, and posterior surfaces.

Figure 02: Carpus

Though humans have eight carpal bones, the number varies among different vertebrates. Furthermore, the structure of the carpus varies widely between different groups of tetrapods.

What are the Similarities Between Tarsal and Carpal Bones?

Tarsal and carpal bones are important parts of the skeleton of vertebrates.
Both are clusters of several small bones.
Moreover, they are organized into rows.

What is the Difference Between Tarsal and Carpal Bones?

Tarsal bones are the group of seven bones forming the ankle of the foot. On the other hand, carpal bones are the group of eight bones forming the joint between the forearm and the hand. Therefore, this is the key difference between tarsal and carpal bones. In fact, there are seven tarsal bones while there are eight carpal bones. Besides, talus, calcaneus, cuboid, navicular and three cuneiforms are the seven tarsal bones. Meanwhile, scaphoid, lunate, triangular, pisiform, trapezium, trapezoid, capitate, and hamate are the eight carpal bones.

Moreover, another difference between tarsal and carpal bones is their organization. Tarsal bones are organized into three rows as proximal, intermediate and distal, while carpal bones are organized into two rows as proximal and distal.

Summary – Tarsal vs Carpal Bones

Tarsal bones are found in the foot while carpal bones are found in the hand. Tarsal bones are a group of seven bones forming the ankle of the foot. They are organized into three rows in the foot. Carpal bones are a cluster of eight bones forming the wrist of the hand. They are organized into two rows in the hand. So, this is the summary of the difference between tarsal and carpal bones.

Reference:

1. Ross, Carlo. “Bones of the Foot: Tarsal Bones – Metatarsal Bone.” Geeky Medics, 4 Sept. 2018, Available here.
2 The Carpus – Human Anatomy, Available here.

Image Courtesy:

1. “Tarsal bones – animation01” By BodyParts3D is made by DBCLS. – Polygon data is from BodyParts3D (CC BY-SA 2.1 jp) via Commons Wikimedia
2. “Xray hand with color” By Original photo is by Dr. Jochen Lengerke at de.wikipedia. Painted color by User:Was a bee. – File:Xray hand.jpg (Public Domain) via Commons Wikimedia