GENERAL INFORMATION
The dorsal interossei are a group of muscles located in the hand. They are responsible for controlling the movement and positioning of the fingers, particularly in actions involving abduction and adduction of the fingers.
ORIGIN
The dorsal interossei muscles originate from the adjacent sides of the metacarpal bones. Each dorsal interosseous muscle originates from the two adjacent metacarpal bones, excluding the metacarpal bone of the finger it corresponds to.
INSERTION POINT
This muscle inserts onto the extensor expansion of the fingers. They attach near the base of the proximal phalanx and extend to the extensor hood mechanism, allowing for coordinated movement and control of the fingers.
MAJOR ARTERIES
The dorsal interossei muscles receive their blood supply from branches of the radial and ulnar arteries, ensuring proper oxygenation and nutrition to support muscle function.
NEURAL INNERVATION
The deep branch of the ulnar nerve primarily innervates the dorsal interossei. This nerve arises from the brachial plexus and provides both sensory and motor innervation to the muscles.
TRIGGER POINT
Trigger points may develop in the muscles due to muscle tension, overuse, or injury. These trigger points can cause localised pain, tenderness, or referred pain in the hand and fingers.
CONCENTRIC FUNCTION
The concentric function of the dorsal interossei involves the contraction of the muscle fibres, resulting in the abduction of the fingers away from the midline of the hand. This contraction allows for actions such as spreading the fingers apart.
ECCENTRIC FUNCTION
The eccentric function of the dorsal interossei occurs when the muscle fibres lengthen under tension. This function assists in controlled relaxation and return to the neutral position of the fingers.
ISOMETRIC FUNCTION
The isometric function of the muscle involves contracting and generating tension without changing the length of the muscles. This function helps maintain stability and support in the fingers during various hand movements.
RELATED MUSCLE-SCIENTIFIC NAMES
- Musculi interossei dorsales manus: These muscles are responsible for the abduction and coordinated movement of the fingers.
ANTAGONIST MUSCLES
The antagonist muscles to the dorsal interossei include the palmar interossei and the lumbrical muscles. These muscles work in opposition to the dorsal interossei, allowing for coordinated movements and balance of the hand and fingers.
COMMON INJURIES
- Strain or sprain: Overexertion or sudden traumatic events can lead to strain or sprain in the dorsal interossei muscles.
- Tendinitis: Inflammation or irritation of the tendons of the dorsal interossei due to repetitive use or strain.
EXERCISES
- Finger abduction exercises: Perform exercises that involve spreading the fingers apart against resistance, such as using therapy putty or resistance bands.
- Grip strengthening exercises: Perform exercises that target overall grip strength, indirectly strengthening the dorsal interossei.
- Hand coordination exercises: Practice exercises that involve coordinated movements of the fingers, such as playing musical instruments or manipulating objects.
STRETCHES
- Finger adduction stretches: Gently bring the fingers together, applying gentle pressure to stretch the dorsal interossei muscles.
- Hand and finger stretch: Perform stretches that target the flexibility and mobility of the hand and fingers, including stretches for the dorsal interossei.
It’s important to note that before starting any exercise or stretching routine, it is advisable to consult with a healthcare professional or a certified hand therapist to ensure proper technique and to prevent any potential injuries.