GENERAL INFORMATION
The abductor digiti minimi is a muscle located in the hand that plays a role in controlling the movement and stability of the little finger. It is also responsible for the abduction of the little finger away from the other fingers.
ORIGIN
This muscle originates from the pisiform bone of the wrist, which is a small bone located on the anterior (palm) side of the wrist.
INSERTION POINT
This muscle inserts onto the ulnar side of the base of the proximal phalanx of the little finger. It attaches near the metacarpophalangeal joint of the little finger.
MAJOR ARTERIES
It receives its blood supply from branches of the ulnar artery, which provide oxygenated blood to the muscle for its proper function.
NEURAL INNERVATION
The abductor digiti minimi is innervated by the deep branch of the ulnar nerve. This nerve arises from the brachial plexus and provides both sensory and motor innervation to the muscle.
TRIGGER POINT
Trigger points in this muscle may develop due to muscle tension, overuse, or injury. These trigger points may cause localised pain, tenderness, or referred pain in the palm or along the ulnar side of the hand.
CONCENTRIC FUNCTION
The concentric function of this muscle involves the contraction of the muscle fibres, resulting in the abduction of the little finger away from the other fingers. This contraction allows for actions such as spreading the fingers apart.
ECCENTRIC FUNCTION
The eccentric function of this muscle occurs when the muscle fibres lengthen under tension. This function assists in controlled relaxation and return to the neutral position of the little finger.
ISOMETRIC FUNCTION
The isometric function of the abductor digiti minimi involves contracting and generating tension without changing the length of the muscle. This function helps maintain stability and support in the little finger during various hand movements.
RELATED MUSCLE-SCIENTIFIC NAMES
The abductor digiti minimi is also known by its scientific name:
- Abductor minimi digiti manus: This muscle abducts the little finger, moving it away from the other fingers to enhance grip and hand function.
ANTAGONIST MUSCLES
The antagonist muscles to the abductor digiti minimi include the muscles of the adductor group, such as the adductor pollicis and the adductor digiti minimi. These muscles work in opposition to the abductor digiti minimi, allowing for coordinated movements of the hand and fingers.
COMMON INJURIES
Common injuries associated with the abductor digiti minimi may include:
- Strain or sprain: Overexertion or sudden traumatic events can lead to strain or sprain in this muscle.
- Tendinitis: Inflammation or irritation of the tendons of the abductor digiti minimi due to repetitive use or strain.
EXERCISES
Exercises that target and strengthen the abductor digiti minimi include:
- Finger spreads: Spread the fingers apart as wide as possible, focusing on the abduction of the little finger.
- Hand grip strengthening exercises: Gripping objects or using hand grip strengthening tools can indirectly strengthen the abductor digiti minimi.
- Resistance band exercises: Attach a resistance band around the fingers and perform abduction movements against the resistance.
STRETCHES
Stretching the abductor digiti minimi can help improve flexibility and prevent stiffness. Some stretches that target this muscle include:
- Little finger stretch: Gently pull the little finger towards the palm using the opposite hand, feeling a stretch along the ulnar side of the hand.
- Wrist and finger stretches: Perform wrist and finger stretches to maintain flexibility and mobility in the hand and fingers.
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.