What Is Included In The Appendicular Skeleton? | Bones You Can Name

The appendicular skeleton includes the shoulder and hip girdles plus all arm, hand, leg, and foot bones—126 bones in most adults.

If you’ve ever stared at a skeleton chart and thought, “Okay… which bones count as appendicular?” you’re not alone. The appendicular skeleton sounds technical, yet the idea is simple: it’s the set of bones that form your limbs and the bony “bridges” that connect those limbs to the body’s central axis.

This matters in real life. If you’re learning anatomy, you’ll get tested on which bones belong where. If you’re reading an X-ray report, you’ll see limb-bone names everywhere. If you’re building study notes, this is one of those categories that becomes easier once it’s sorted into clean buckets.

Let’s pin it down in plain language, then walk through every region in a way that’s easy to remember.

Appendicular Skeleton Basics In Plain Terms

The human skeleton is often grouped into two big parts: axial (the central line of the body: skull, spine, ribs) and appendicular (the limbs plus their attachment points). The appendicular portion includes the bones of the upper limbs and lower limbs, plus the girdles that anchor each limb to the trunk. A standard adult count is 126 bones in this portion alone.

Two details make people second-guess themselves:

• “Girdles” count. The shoulder girdle and hip girdle are part of appendicular, even though they sit close to the trunk.
• Hands and feet count fully. Wrists, palms, ankles, toes—those small bones are a big chunk of the total.

One quick anchor: if the bone is part of an arm or leg, it’s appendicular. If it connects that arm or leg to the trunk, it’s appendicular too. If it forms the skull, spine, or rib cage, it’s axial.

What Is Included In The Appendicular Skeleton? By Region

This is the clean map most classes use. The appendicular skeleton splits into four main areas, and each area has a predictable “pattern” you can learn:

• Pectoral (shoulder) girdle — the bones that anchor the upper limb.
• Upper limb — arm, forearm, wrist, hand, fingers.
• Pelvic (hip) girdle — the bones that anchor the lower limb.
• Lower limb — thigh, leg, ankle, foot, toes.

If you want an official breakdown with bone counts by region, both OpenStax’s “Divisions of the Skeletal System” and the NCI SEER “Appendicular Skeleton (126 bones)” page list the same core grouping and counts.

Pectoral Girdle Bones And What They Do

The pectoral girdle is your upper-limb anchor. It’s built for reach and range of motion, so it trades some stability for mobility. That’s why shoulders can move in so many directions—and why shoulder injuries are common.

Clavicle

The clavicle (collarbone) runs from the upper sternum area out toward the shoulder. Think of it as a strut that holds the shoulder out from the chest, giving room for arm movement and muscle attachment. It also helps transmit forces from the arm back toward the trunk.

Scapula

The scapula (shoulder blade) sits on the back of the rib cage. It’s a sliding platform that changes position as you move your arm. The socket for the upper arm bone is part of the scapula, which helps explain why scapular motion and shoulder motion are linked.

Both sides together: two clavicles and two scapulae.

Upper Limb Bones From Shoulder To Fingertips

The upper limb has a tidy progression: one long bone in the arm, two long bones in the forearm, then clusters in the wrist and hand. If you learn the order, you can label most diagrams fast.

Humerus

The humerus is the long bone of the arm (shoulder to elbow). Its top end forms part of the shoulder joint. Its lower end forms part of the elbow joint.

Radius And Ulna

Your forearm has two bones:

• Radius — on the thumb side when your palm faces forward.
• Ulna — on the pinky side, with the prominent elbow point at its top end.

Those two bones allow rotation of the forearm (turning the palm up and down). That rotation is a big reason the upper limb is so versatile in daily tasks.

Carpals, Metacarpals, And Phalanges

The hand includes three sets of bones:

• Carpals — the wrist bones, eight per hand (16 total).
• Metacarpals — the palm bones, five per hand (10 total).
• Phalanges — the finger bones, 14 per hand (28 total).

Study trick that stays honest: carpals are “close” to the forearm (wrist), metacarpals are the “middle” of the hand (palm), phalanges are the “far” end (digits).

That’s the entire upper limb side: humerus, radius, ulna, carpals, metacarpals, and phalanges—plus the pectoral girdle bones that connect the limb to the trunk.

Pelvic Girdle Bones And Why They’re Built Differently

The pelvic girdle is the lower-limb anchor. Unlike the shoulder region, this area is built for stability and load transfer. When you stand, walk, jump, or carry weight, the pelvis helps route force between the spine and the legs.

Hip Bones (Coxal Bones)

Each side has one hip bone, and each hip bone forms from three parts that fuse during growth:

• Ilium — the broad upper “wing.”
• Ischium — the lower back portion that bears weight when you sit.
• Pubis — the lower front portion that meets at the midline.

In adult anatomy lists, you’ll often see “hip bone” as the single named bone per side, even though its three parts are still taught for landmarks and muscle attachment points.

Both sides together: two hip bones total in the appendicular skeleton.

Region	Bones Included	Typical Adult Count
Pectoral girdle	Clavicle, scapula	4
Arm	Humerus	2
Forearm	Radius, ulna	4
Wrist	Carpals	16
Hand	Metacarpals	10
Digits (hand)	Phalanges	28
Pelvic girdle	Hip (coxal) bones	2
Thigh	Femur	2
Knee	Patella	2
Leg	Tibia, fibula	4
Ankle	Tarsals	14
Foot	Metatarsals	10
Digits (foot)	Phalanges	28

Lower Limb Bones From Hip To Toes

The lower limb mirrors the “one bone, two bones, many small bones” vibe, but it’s tuned for bearing weight and moving the body through space. If you’re memorizing, go from top to bottom and keep your landmarks straight.

Femur

The femur is the thigh bone. It’s the longest bone in the body and forms the main bony part of the hip joint at its top end. Its lower end helps form the knee joint.

Patella

The patella (kneecap) sits within the tendon of the thigh muscles and improves leverage at the knee. It also protects the front of the joint. Not everyone thinks of it as a “real bone” at first glance, but it’s part of the standard appendicular count.

Tibia And Fibula

Your lower leg has two bones:

• Tibia — the shin bone, the main weight-bearing bone below the knee.
• Fibula — the thinner lateral bone that helps with ankle stability and muscle attachment.

On many diagrams, the tibia looks like the star of the show. That’s fair. Still, the fibula has a real job—especially near the ankle.

Tarsals, Metatarsals, And Phalanges

The foot follows the same three-part naming pattern as the hand, with slightly different terms:

• Tarsals — ankle and rear-foot bones, seven per foot (14 total).
• Metatarsals — mid-foot bones, five per foot (10 total).
• Phalanges — toe bones, 14 per foot (28 total).

One reason feet feel complex is that tarsals form arches and meet the ground at shifting angles. That’s also why ankle sprains and mid-foot issues can be stubborn.

Common Mix-Ups That Trip People Up

These mix-ups show up in quizzes and lab practicals all the time. If you lock these down, you’ll save yourself points.

Shoulder Girdle Vs. Rib Cage

The scapula sits on the back of the rib cage, but ribs are axial. The scapula is appendicular. The clue is function: the scapula belongs to upper-limb mechanics, while ribs form the chest cage.

Hip Bones Vs. Sacrum

The hip bones are appendicular. The sacrum is axial because it’s part of the spine. They meet at the sacroiliac joints, which makes the border feel blurry at first.

Wrist And Ankle Bone Names

“Carpals” are wrist bones. “Tarsals” are ankle bones. If you swap them, the rest of the hand/foot labeling tends to unravel. Say it out loud: carpal = wrist, tarsal = ankle.

How These Bones Link Up At Major Joints

Knowing which bones belong to the appendicular skeleton is step one. Step two is knowing how they meet. That’s where the names on diagrams start to feel logical.

Here are the big joint meetups you’ll see again and again:

• Shoulder joint — humerus meets scapula.
• Elbow region — humerus meets radius and ulna.
• Wrist region — radius meets carpals.
• Hip joint — femur meets hip bone.
• Knee region — femur meets tibia, with the patella in front.
• Ankle region — tibia and fibula meet tarsals.

Area	Main Bones In Contact	Easy Reminder
Shoulder	Scapula + humerus	Upper arm plugs into the shoulder blade socket
Elbow	Humerus + radius/ulna	One bone above, two below
Wrist	Radius + carpals	Thumb-side forearm bone meets wrist cluster
Hip	Hip bone + femur	Thigh bone head sits in the pelvis socket
Knee	Femur + tibia (+ patella)	Big hinge with kneecap in front
Ankle	Tibia/fibula + tarsals	Leg bones form a bracket over the foot

A Simple Checklist To Test Yourself Fast

If you want a quick self-check without flipping pages, run this list in your head. If you can say it cleanly, you’ve got the category.

Upper Side

• Pectoral girdle: clavicle, scapula
• Arm: humerus
• Forearm: radius, ulna
• Hand: carpals, metacarpals, phalanges

Lower Side

• Pelvic girdle: hip bones (ilium, ischium, pubis as parts)
• Thigh: femur
• Knee: patella
• Leg: tibia, fibula
• Foot: tarsals, metatarsals, phalanges

That’s the full set most courses expect when they ask this question. Once it clicks, it stops feeling like a random list and starts feeling like a map.