Contents
General information
- Is a part of the thenar muscles
Position
- Superficial in the area between the thumb and index finger
Origin
- Oblique-head
- Os capitatum
- Base of 2. metacarpal
- Base of 3. metacarpal
- Transverse-head
- Palmar surface of 3. metacarpal-head
Insertion
- Oblique-head
- Base of proximal phalanx of the thumb, medial side
- Dorsal digital expansion
- Transverse-head
- Base of the proximal phalanx of the thumb, medial side
Main function
- Thumb CMC
- Adduction
Secondary function
- Thumb CMC
- Flexion
- Thumb MCP
- Flexion
- Thumb IP
- Extension
Nerve innervation
- Segmental
- C8-Th1
- Peripheral
- Nervus ulnaris
Arterial supply
- Radial artery
Palpation
- Patient position: Sitting or supine
- Place your fingers in the area between the index finger and the thumb
- Ask the patient to make an adduction movement of the CMC of the thumb while you feel for the contraction
Strength test
- Patient position: Sitting or supine
- Ask the patient to hold the thumb in an adducted position
- Give resistance towards the medial surface of the thumb in the direction of abduction so that the patient is giving force towards adduction