---
title: "Lateral Epicondyle of the Humerus | Anatomy I"
description: "The lateral epicondyle of the humerus is the outer elbow bump where forearm extensor muscles attach in Anatomy and Physiology I."
canonical: "https://fiveable.me/anatomy-physiology/key-terms/lateral-epicondyle-of-the-humerus"
type: "key-term"
subject: "Anatomy and Physiology I"
unit: "Unit 8"
---

# Lateral Epicondyle of the Humerus | Anatomy I

## Definition

The lateral epicondyle of the humerus is the bony bump on the outer side of the lower humerus, just above the elbow. In Anatomy and Physiology I, you use it as a muscle attachment landmark for the forearm extensor group.

## What It Is

The lateral epicondyle of the humerus is the small bony prominence on the outer side of the distal humerus, right above the elbow joint. In Anatomy and Physiology I, it is mainly a landmark for muscle attachment, especially for the forearm muscles that extend the wrist and fingers.

If you place your hand on the outside of your elbow, you are near the lateral epicondyle. It is part of the humerus, not a separate bone, and it sits close to the joint where the humerus meets the radius and ulna. Because it sticks out, it is easy to identify on diagrams, models, and sometimes on a living person.

This spot matters because many muscles that move the wrist and hand begin, directly or indirectly, from the common extensor tendon attached near the lateral epicondyle. When those muscles contract, they help you lift your wrist, straighten your fingers, and stabilize the forearm during gripping. That is why this landmark is tied to movement even though the bone itself does not move.

It also helps you orient the upper limb. If you can find the lateral epicondyle, you can tell left from right, locate the elbow region, and compare it with the medial epicondyle on the inner side of the arm. That comparison comes up a lot when you are learning bone markings, muscle origins, and joint anatomy.

A common mistake is treating the lateral epicondyle like a muscle or a joint surface. It is neither. It is a projection of the humerus that serves as a roughened attachment area, and its size and texture reflect the pull of the muscles and ligaments that anchor there. In lab, it is usually identified by position, not by a smooth articular surface.

## Why It Matters

The lateral epicondyle of the humerus shows how bone markings connect structure to movement in Anatomy and Physiology I. You are not just memorizing a bump on a bone. You are learning where muscles anchor, how the elbow region is organized, and how the upper limb produces coordinated motion.

This landmark is especially useful when you study the extensor muscles of the forearm. Those muscles are responsible for actions like extending the wrist and fingers, and their relationship to the lateral epicondyle explains why force transfers from the humerus into the hand. If you know the attachment site, it is easier to make sense of muscle names, origins, and actions instead of memorizing them as random facts.

It also shows up in clinical discussion. Pain near the lateral epicondyle can be linked to overuse of the wrist extensors, which is why anatomy labs and class examples often connect this area to repetitive gripping or lifting. Even if your course does not go deep into pathology, this landmark gives you a clear example of how anatomy connects to real movement and strain.

When you can identify this feature on a skeleton, model, or image, you are also proving you can read anatomical landmarks accurately. That skill carries over to the rest of the upper limb, where small differences in bone markings tell you a lot about function.

## Connections

### Humerus

The lateral epicondyle is one specific landmark on the humerus, so you need the larger bone first. When you study the humerus, you are learning how its distal end forms the elbow region and provides attachment points for muscles that move the forearm and hand. The epicondyle only makes sense in relation to the whole bone.

### [Medial Epicondyle of the Humerus](/anatomy-physiology/key-terms/medial-epicondyle-of-the-humerus)

This is the closest comparison because both epicondyles are bony projections on the distal humerus. The lateral epicondyle is on the outer side, while the medial epicondyle is on the inner side. In lab, comparing them helps you orient the bone correctly and avoid mixing up the medial and lateral sides of the arm.

### [Elbow Joint](/anatomy-physiology/key-terms/elbow-joint)

The lateral epicondyle sits just above the elbow joint, so the two structures are easy to confuse at first. The elbow joint is where bones articulate and movement happens, while the epicondyle is a nearby attachment landmark. Knowing the difference helps you separate joint surfaces from bone markings that support movement.

### [coronoid fossa](/anatomy-physiology/key-terms/coronoid-fossa)

The coronoid fossa is another distal humerus landmark, but it is a depression rather than a bump. It works with elbow flexion by receiving the coronoid process of the ulna. Pairing it with the lateral epicondyle helps you see how the distal humerus includes both attachment points and spaces for movement.

## On the AP Exam

A lab practical or bone-identification quiz usually asks you to point out the lateral epicondyle on a skeleton, model, or image and name its location relative to the elbow. You may also be asked which muscle group attaches there or how it helps you orient the humerus as left or right. On written tests, this term often appears in questions about bone markings, muscle origins, or upper-limb movement. If a question mentions pain on the outside of the elbow, you should connect the region back to the lateral epicondyle and the forearm extensor tendons rather than guessing a random bone name. In diagrams, look for the outer distal bump of the humerus, just superior to the elbow joint.

## lateral epicondyle of the humerus vs Medial Epicondyle of the Humerus

These are both bumps on the distal humerus, but they are on opposite sides. The lateral epicondyle is on the outer side and is linked more with the forearm extensor muscles, while the medial epicondyle is on the inner side and is easier to feel as the larger, more prominent inner elbow bump. If you mix them up, you will also mix up muscle attachment patterns and bone orientation.

## Key Takeaways

- The lateral epicondyle of the humerus is the bony bump on the outer side of the lower humerus, just above the elbow.
- In Anatomy and Physiology I, it matters because it is an attachment site for forearm muscles, especially the extensor group.
- You can use it as a landmark to orient the humerus and tell the lateral side from the medial side.
- It is a bone marking, not a muscle and not the joint itself.
- If a question mentions the outside of the elbow, think about the lateral epicondyle and the muscles that attach there.

## FAQs

### What is the lateral epicondyle of the humerus in Anatomy and Physiology I?

It is the small bony projection on the outer side of the distal humerus, just above the elbow. In A&P I, you learn it as a muscle attachment landmark, especially for muscles that extend the wrist and fingers.

### Is the lateral epicondyle part of the elbow joint?

It is nearby, but it is not the joint surface itself. The elbow joint is where the humerus meets the radius and ulna, while the lateral epicondyle is a projection above that joint that helps anchor muscles and ligaments.

### What attaches to the lateral epicondyle of the humerus?

The common extensor tendon and related forearm extensor muscles attach there. That is why this landmark is tied to wrist and finger extension and to the mechanics of gripping and lifting.

### How do I tell the lateral epicondyle from the medial epicondyle?

Use side and shape. The lateral epicondyle is on the outer side of the arm, while the medial epicondyle is on the inner side and is usually easier to feel as the larger bump. Comparing the two helps you orient the humerus correctly in lab.

## Related Study Guides

- [8.2 Bones of the Upper Limb ](/anatomy-physiology/unit-8/2-bones-upper-limb/study-guide/TisVx2uINDAYy67v)

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