Section 01 of 20
Introduction
Palmaris longus is a thin, spindle-shaped muscle on the front of the forearm with a short belly and a very long tendon. The tendon runs down the middle of the wrist, in front of the flexor retinaculum, and fans out into the palmar aponeurosis, the tough fascia of the palm.
It is one of the most variable muscles in the body. It is missing on one or both sides in a fair proportion of people (commonly reported around 10 to 15 percent), and its absence does not cause a noticeable loss of function.
Section 02 of 20
Origin
| Origin | Medial epicondyle of the humerus through the common flexor tendon, with fibers from the intermuscular septa and the deep fascia of the forearm. |
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An anatomical image for this section will be added when verified source media becomes available.
Section 03 of 20
Insertion
| Insertion | The distal half of the flexor retinaculum and the palmar aponeurosis of the hand. |
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An anatomical image for this section will be added when verified source media becomes available.
Section 04 of 20
Actions
No dedicated action video is currently available. This movement is explained below and video will be added when verified source media becomes available.
| Primary action | Weak wrist flexion. |
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| Secondary actions | Tension of the palmar aponeurosis, cupping the palm, and weak elbow flexion. |
| Movement at the joint | Wrist joint (and palmar fascia); weakly the elbow. |
| Heads / fiber groups | Single short belly with a long tendon. |
| Functional examples | Gripping a handle; pushing up from a surface; carrying a bag; cupping the palm. |
Wrist flexion
A weak flexor of the wrist, working with the other wrist flexors.
Tension of the palmar aponeurosis
Tightens the fascia of the palm, which helps anchor the skin and support gripping.
Cupping the palm
Helps hold the palm in a cupped position; it also weakly assists elbow flexion.
Section 05 of 20
Nerve Innervation
| Nerve | Median nerve, roots C7–C8. |
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The tendon lies very close to the median nerve at the wrist. Tingling or numbness in the thumb, index, and middle fingers may reflect median nerve involvement, not only muscle tightness.
Section 06 of 20
Blood Supply
| Blood | Branches of the ulnar artery, mainly the posterior ulnar recurrent artery and forearm muscular branches. |
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Section 07 of 20
Pictures and Visual Anatomy
An anatomical image for this section will be added when verified source media becomes available.
Section 08 of 20
Functional Movement
Palmaris longus helps with gripping and pressing through the palm, such as holding a tool handle, pushing up from a surface, or carrying a bag. Because of its many variations, its role is small compared with the other forearm flexors.
Section 09 of 20
Synergists and Antagonists
Synergists: flexor carpi radialis and flexor carpi ulnaris (wrist flexion) and flexor digitorum superficialis. Antagonists: the wrist extensors: extensor carpi radialis longus and brevis, and extensor carpi ulnaris.
Section 10 of 20
Palpation and Location
Client position and technique
Position the client with the forearm supported, palm up. Ask the client to touch the thumb and little finger together and flex the wrist against light resistance. The tendon appears as a prominent cord in the middle of the front of the wrist, over the median nerve and between flexor carpi radialis and flexor carpi ulnaris. Follow the thin belly toward the medial epicondyle. If no tendon appears, the muscle may be absent.
Protect nearby structures
The median nerve lies directly beneath the tendon at the wrist. Avoid deep or sustained pressure over the wrist crease and carpal tunnel, and stop if the client reports tingling, numbness, or sharp pain.
Section 11 of 20
Massage Therapy Relevance
Palmaris longus is a small muscle, but its tendon is a useful landmark for the median nerve and the wrist flexors, and the muscle belongs to the group involved in medial elbow pain and forearm tension. Because it is absent in some people, the wrist can look different from client to client.
Section 12 of 20
Dysfunction: What Happens When Movement Goes Wrong
Changes in how a muscle works can change how a joint moves. The points below describe possibilities that may be associated with altered muscle function; they are not diagnoses, and one muscle is never assumed to be the sole cause of a problem.
When the muscle is weak
Weakness is difficult to detect because the muscle is small and may be absent; wrist flexion is mainly carried by the other flexors.
When it is tight or shortened
Tightness may be associated with a tight forearm and limited wrist extension.
When it is overused
Repetitive gripping and wrist flexion may overload the common flexor tendon and may contribute to medial elbow and forearm ache.
When it is strained
A strain may cause forearm pain with resisted wrist flexion; medial elbow and nerve problems can look similar.
When it is inhibited or others compensate
Reduced activation may be associated with more work by the other wrist flexors.
When it does not coordinate well with synergists and antagonists
Poor coordination with the other flexors and the wrist extensors may alter grip mechanics and may be associated with forearm and elbow symptoms.
Section 13 of 20
Conditions, Pathologies, and Pain Relationships
Medial elbow pain (golfer's elbow)
Overuse of the common flexor tendon at the medial epicondyle may cause pain and tenderness there, and the wrist flexors including palmaris longus may be involved.
Palmar fascia tension and Dupuytren contracture
Thickening of the palmar aponeurosis may cause firm nodules and finger contracture in the palm; this needs assessment and is not treated as simple muscle tightness.
Anomalous muscle belly
Uncommon variants of the muscle may crowd the carpal tunnel and may be associated with median nerve symptoms.
Differential considerations
Carpal tunnel syndrome, flexor tendon problems, cervical radiculopathy, and medial elbow problems can cause similar forearm and wrist symptoms.
Section 14 of 20
Example Clinical Relationship
A client who grips a tool handle for many hours reports an ache on the inner side of the elbow and a tight front of the forearm. The common flexor group, including palmaris longus when present, may be involved, and the pattern may be associated with golfer's elbow, but nerve and joint problems can look similar. Gentle work along the forearm flexors may support comfort, while progressive hand weakness or a hot swollen wrist needs referral.
Section 15 of 20
Massage and Treatment Approaches
For healthy, non-acute tissue, position the client supine or seated with the forearm supported, palm up. Begin with light effleurage from the wrist to the elbow, then use gentle kneading, thumb strokes along the flexor group, and comfortable stretching of the wrist into extension.
| Movement | Use gentle wrist and finger extension stretches within comfort; do not force range. |
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| Regional work | Consider flexor carpi radialis, flexor carpi ulnaris, flexor digitorum superficialis, pronator teres, and the common flexor origin at the medial epicondyle when assessment supports it. |
| Avoid | Deep pressure over the wrist crease and carpal tunnel, over an acute tendon injury, or at any point that reproduces numbness or tingling. |
Section 16 of 20
Precautions and Contraindications
Precautions and contraindications
- Recent forearm, wrist, or elbow injury, fracture, or surgery, including recent tendon harvest.
- Use caution with known carpal tunnel syndrome, rheumatoid arthritis, or palmar nodules.
- Use caution with anticoagulant use or easy bruising.
- Stop if pressure causes numbness, tingling, or sharp pain.
Section 17 of 20
Red Flags and When to Refer
Red flags and referral
- Progressive numbness, weakness, or wasting in the hand.
- A hot, red, swollen wrist or palm, especially with fever.
- A firm nodule or cord in the palm with progressive finger bending.
- Arm pain with neck pain, chest pain, or shortness of breath.
Section 18 of 20
Study Summary
Attachments
Origin: medial epicondyle via the common flexor tendon. Insertion: flexor retinaculum and palmar aponeurosis.
Actions
Weak wrist flexion; tenses the palmar aponeurosis.
Supply
Median nerve (C7–C8); ulnar artery branches.
Section 19 of 20
Instructor Narration
Open narration transcript
Palmaris longus is a slender forearm muscle with a long tendon. It is absent in some people.
It arises from the medial epicondyle through the common flexor tendon and inserts on the flexor retinaculum and the palmar aponeurosis of the hand.
It weakly flexes the wrist and tenses the palmar aponeurosis. The other wrist flexors help it, and the wrist extensors oppose it.
The median nerve supplies it, from C7 to C8, and branches of the ulnar artery provide its blood.
To find the tendon, ask the client to touch the thumb to the little finger and flex the wrist, then look for the cord at the middle of the wrist. If it is not there, the muscle may be absent. Avoid deep pressure over the carpal tunnel.
Golfer's elbow, palmar fascia problems, carpal tunnel syndrome, and neck problems can overlap. Refer progressive hand weakness, a hot swollen wrist, a palm nodule with finger contracture, or arm symptoms with neck or chest pain.
Remember: medial epicondyle to the flexor retinaculum and palmar aponeurosis; weak wrist flexion; median nerve.
Section 20 of 20