This document provides an overview of general myology (the study of muscles). It discusses the three main types of muscles - smooth, cardiac, and skeletal muscles. Skeletal muscles are voluntary muscles that are attached to bones and have bundles of fibers. The document describes the layers of connective tissue (epimysium, perimysium, endomysium) that surround skeletal muscle fibers. It also discusses the arrangements of skeletal muscle fibers, their attachments via tendons, and associated structures like tendon sheaths and bursae.

1. General Myyology
By
Prof. Dr. Abdelmohaimen Mostafa Saleh
Professor of Anatomy & Embryology
Assiut University
‫أ‬.‫د‬/‫صالح‬ ‫مصطفى‬ ‫عبدالمهيمن‬

2. Myology is the science which deals with the
study of muscles.
Muscles are classified morphologically &
functionally into 3 categories, smooth, cardiac
& skeleton muscles :

3. MUSCLE FUNCTIONS
• The muscles have 4 important functions:
1. Production of movement
– External and internal
2. Maintaining posture
3. Stabilizing joints
4. Generating heat

4. MUSCLE TYPES
1- Smooth muscles :
- found in the internal organs and blood vessels.
- They perform weak but sustained contractions.
- They are involuntary ( i.e. not under the control of will).
2- Cardiac muscles :
They are involuntary and form the bulk of the heart.
3- Skeletal muscles :
They are voluntry muscles, attached to the skeleton.
Some fibers appear dark ( red ), others are pale ( white(
Contraction of red fibers is tonic and prolonged.
Each muscle consists of bundles and each bundle
consists of fibers (muscle cells).

6. SKELETAL MUSCLE
• How is the muscle formed ?
• Muscles are made of several tissue types which include
muscle, connective, blood vessels, and nerves.
• There are 3 connective tissue covers of muscle fibers.
– Epimysium – dense irregular connective tissue that
surrounds a muscle (many fascicles).
– Perimysium – fibrous connective tissue that
surrounds each fascicle (bundle) of muscle fibers.
– Endomysium – reticular connective tissue that
surrounds each muscle fiber (cell).

7. THE CONNECTIVE TISSUE
WRAPPINGS – A VIEW

8. NB :
▪ New skeletal muscle fibers are not formed
after birth,
▪ Growth in muscle size is due to enlargement
of the existing fibers.
▪ Damaged muscle fibers are replaced by
connective tissue.
▪

9. Arrangements of skeletal muscle fibers :
1.Parallel arrangement.
2.Pennate ( feather-like(
The fibers attach to the tendon at an angle. They
may be :
a.Unipennate . b- bipennate
c- Multipennate
3.Fusiform : Muscle fibers converge upon a tendon at
both ends.

11. Attachment of skeleton
muscles :
- Mostly, each skeleton
muscle has 2
attachments, origin
&nsertion, the insertion is
the movable attachment
- In the limbs, the insertion
being the distal
attachment.
- The origin and insertion
may be tendinous or
fleshy.

12. Classification of skeletal muscles :
- According to function : extensors, flexors,
adductors ,abductors, levators, depressors, sphincters
& orbicularis (Muscles associated with the skin are
cutaneous muscles).
− According to number of divisions : Biceps (2
heads), Triceps (3 heads) & Quadriceps(4 heads).
− According to shape : Quadratus (rectangular),
Rhomboideus (resemble a rhomboid) & Serratus (with
serrated border)
− According to position: superficial, deep, external &
internal.

13. Structures associated with the muscles :
1- Tendons :
− It is composed of dense connective tissue to which the
muscle fibers are attached.
− It is either cord-like such as in fusiform muscles or flat
sheath as in flat muscles. ( NB : Some tendons contain
piece of bone called sesamoid bone )
2-Tendon sheath :
− Long tendons are surrounded by tendon sheath
containing synovial fluid to make its movement smooth.
3- Bursa :
− It is a sac filled with synovia.
− It facilitates the movement of a tendon over a bony
prominent.