Extensor Indicis Anatomy: Origin, Insertion, Action
Muscle Anatomy of the Extensor Indicis
Origin: Posterior surface of the ulna and the interosseous membrane
Insertion: Dorsal surface of the base of the middle phalanx and distal phalanx of the index digit
Actions: Extension of the second digit (index finger)
Innervation: Radial nerve (C6, C7, C8)
Blood Supply: Posterior interosseous artery from the ulnar artery
Muscle Anatomy: Extensor Indicis Actions
Primary Actions of the Extensor Indicis
1. Extension of the second digit at the metacarpophalangeal joint
Agonists:
- Extensor Digitorum
Antagonists:
- First Dorsal Interosseous
- First Palmar Interosseous
- First Lumbrical
- Flexor Digitorum Superficialis
- Flexor Digitorum Profundus
2. Extension of the second digit at the proximal interphalangeal joint
Agonists:
- Extensor Digitorum
- First Lumbrical
- First Dorsal Interosseous
- First Palmar Interosseous
Antagonists:
- Flexor Digitorum Superficialis
- Flexor Digitorum Profundus
3. Extension of the second digit at the distal interphalangeal joint
Agonists:
- Extensor Digitorum
- First Lumbrical
- First Dorsal Interosseous,
- First Palmar Interosseous
Antagonists:
- Flexor Digitorum Profundus
Secondary Actions of the Extensor Indicis:
1. Assists with adduction of the second digit at the carpometacarpal joint
Agonists:
- First Palmar Interosseous
Antagonists:
- First Dorsal Interosseous
Information about cause and effect of Extensor Indicis pain:
Recommended Anatomy Books:
Anatomy Coloring Book
The Anatomy Coloring Book is one of the best study and reference books for beginning anatomy students. The diagrams are clearly labeled and allow you to see the relationship and placement of the various structures of the body. You will also be surprised how the act of coloring will help with recall. But this is not just a beginners book, it is also great for practitioners and therapists to have on hand to use with clients and patients to use as a visual reference.
Human Muscle Anatomy
The Trail Guide To The Body is another excellent book to help you learn the musculature of the human body. Though the book is geared toward massage therapists and physical therapist assistants, the book with its illustrations and text helps anyone gain a thorough understanding of the human musculoskeletal system and movement. I highly recommend this book for anyone studying anatomy and believe that MTs, PTAs, and teachers of body movements should have this book in their possession. I also highly recommend this book for the lay person who wants to gain understanding of the muscle, skeletal system and how our bodies move. This book will not disappoint!
Basic Clinical Massage Therapy
Out of the scores of books in my office Basic Clinical Massage Therapy is by far the most referenced book in my library. The musculoskeletal system is overlaid on human models allowing you to learn the precise location, origin and insertions of each muscle. The models are pictured in various poses throughout the book which also helps you visualize muscles in motion and their actions relationship with the skeletal structure and other muscles. Though it is written for massage therapists, it is an excellent book for anyone who wants to learn about the muscular system. MT's will benefit from recommended treatments for each muscle.
Muscle Anatomy Flashcards
Musculoskeletal Anatomy Flashcards Are you a student or professional therapist who needs to brush up on the musculoskeletal system? Dr. Joseph E. Muscolino DC has developed a comprehensive set of flashcards that will help develop a mind's picture of exactly where the muscles lie under the skin. A highly recommended study aid for students. Great for non students who want an easy comprehensive anatomy guide.
