Upper Limb Muscles
Explore the upper limb muscles by region: the shoulder, arm, forearm and hand. Each section of this free anatomy lab uses labelled images to help medical students learn the muscles, their actions and their nerve supply.
Upper Limb Muscles by Region
Practice Upper Limb anatomy questions
1230 exam-style anatomy MCQs with explanations, matched to this lab. Test what you just studied.
Upper Limb Anatomy MCQs: mixed practice questions
Try 5 sample questions drawn from across Upper Limb. Tap an answer to check it.
Which nerve innervates the muscles of the anterior compartment of the arm?
From: ArmCorrect answer: B. The musculocutaneous nerve is the motor nerve of the anterior compartment muscles.Which nerve supplies most muscles of the anterior compartment of the forearm?
From: Clinical AnatomyCorrect answer: B. The median nerve supplies most muscles of the anterior forearm, with the usual ulnar-nerve exceptions.Flexor digitorum superficialis inserts on the:
From: ForearmCorrect answer: A. Flexor digitorum superficialis inserts on the middle phalanges.Which muscles produce wrist abduction?
From: JointsCorrect answer: C. Flexor carpi radialis and the radial wrist extensors act together to abduct the wrist.Serratus anterior originates from the:
From: Pectoral RegionCorrect answer: A. Serratus anterior originates from the upper eight ribs.
What Are the Upper Limb Muscles?
The upper limb muscles move the shoulder, elbow, wrist and fingers. They give the arm its range, strength and fine control, from lifting a weight to writing with a pen. To learn them in a clear order, anatomists divide the upper limb muscles into regions: the muscles that connect the limb to the trunk, the shoulder, the arm, the forearm and the hand. Each region has its own nerve supply and its own main actions, which makes the groups easier to remember.
Seven Muscle Groups to Study
Our free anatomy lab covers seven groups. Open each page to study the muscles with labelled images:
- Anterior Thoraco-Appendicular Muscles: the muscles on the front of the chest that connect the trunk to the upper limb, including the pectoral muscles and serratus anterior.
- Posterior Axio-Appendicular Muscles: the back muscles that connect the spine to the shoulder girdle, such as trapezius, latissimus dorsi and the rhomboids.
- Scapulo-Humeral Muscles: the muscles that connect the scapula to the humerus, including the deltoid and the rotator cuff.
- Arm Muscles: the flexors at the front and the triceps at the back of the arm.
- Anterior Forearm Muscles: the flexors of the wrist and fingers and the pronators.
- Posterior Forearm Muscles: the extensors of the wrist and fingers and the supinator.
- Hand Muscles: the small intrinsic muscles that control the thumb and fingers.
Shoulder Muscles: The Rotator Cuff and Deltoid
The shoulder muscles have a hard job: they must move the most mobile joint in the body while keeping it stable. The deltoid abducts the arm, and the four rotator cuff muscles (supraspinatus, infraspinatus, teres minor and subscapularis) hold the head of the humerus in the shallow socket of the scapula. Serratus anterior holds the scapula against the chest wall, and injury to its nerve causes a winged scapula.
Arm and Forearm Muscles: Flexors and Extensors
In the arm, the anterior muscles (biceps brachii, brachialis and coracobrachialis) mainly flex the elbow and are supplied by the musculocutaneous nerve, while the triceps at the back extends it and is supplied by the radial nerve. In the forearm, the anterior muscles are mostly flexors and pronators supplied by the median and ulnar nerves, and the posterior muscles are extensors and the supinator, supplied by the radial nerve.
How to Study the Upper Limb Muscles
- Learn one region at a time, starting with the shoulder, then the arm, forearm and hand.
- For every muscle, ask four questions: where does it start and end, what does it do, which nerve supplies it, and what happens if that nerve is damaged?
- Test yourself. Practise with our upper limb anatomy flashcards, then check your knowledge with the Questions Bank.
Learn the upper limb osteology first, so you know where each muscle attaches. To compare with the leg, see our lower limb muscles page. For a full reference list of every muscle in the body, see this list of muscles of the human body. More practical sessions are available in our medical labs.
Why Do Medical Students Need to Know These Muscles?
The upper limb muscles are a favourite in anatomy exams and a daily part of clinical practice. Weakness in a muscle group often points to a nerve injury: an injured radial nerve causes wrist drop, and compression of the median nerve at the wrist causes carpal tunnel syndrome. Rotator cuff injuries are among the most common shoulder problems. Knowing which nerve supplies which group helps you examine a patient and interpret findings.
Frequently Asked Questions
What are the main upper limb muscles? They are the muscles that connect the limb to the trunk, the shoulder muscles, the arm muscles, the anterior and posterior forearm muscles, and the intrinsic muscles of the hand.
What are the rotator cuff muscles? Supraspinatus, infraspinatus, teres minor and subscapularis.
Which nerve supplies the triceps? The radial nerve.
Which muscles flex the elbow? Mainly biceps brachii and brachialis, supplied by the musculocutaneous nerve.
How do I memorise these muscles? Learn them region by region, link each muscle to its action and nerve supply, and review them with flashcards in short daily sessions.
Is this anatomy lab free? Yes. All the pages in our anatomy lab are free for medical students.