Transcript File
Human Anatomy Chapter 2 Sport Books Publisher 1 Muscles of the Human Body Sport Books Publisher 2 over 600 in the human body allow the skeleton to move to cause movement, both ends of each muscle must be attached to bone – origin or proximal attachment - the attachment closer to the centre of the body – insertion or distal attachment - the attachment away from the centre of the body Sport Books Publisher 3 Facial Muscles Sport Books Publisher 4 Various functions of the facial muscles: – enable you to change expression and display your emotions outwardly – allow you to close your eyes and blink – essential for opening and closing the mouth for: – keeping food in the mouth – allowing you to chew – allowing you to form words Tongue – function: • allows you move food around in your mouth and get it to a position to be swallowed • allows you to pronounce words and speak intelligibly Sport Books Publisher 5 Neck Muscles Sport Books Publisher 6 Neck Muscles There are muscles posterior, lateral and anterior to the neck or cervical region These muscles: – Maintain the position in which the head sits on the 1st cervical vertebra (atlas) i.e. they hold up our head – Also permit a wide range of movement Sport Books Publisher 7 Sternocleidomastoids The most important anterior pair of muscles Movements: – Acting together, they flex the head toward the chest – Individually, each muscle tilts the face up and toward the opposite side Sport Books Publisher 8 Erector spinae muscles Important posterior neck muscles Attach to sacrum inferiorly, and to the skull superiorly maintain your erect position – Therefore, they are also called anti-gravity muscles – When someone faints, these muscle no longer function and the body falls face forward to the ground Sport Books Publisher 9 Trapezius, upper fibres Important lateral neck muscles Movements: – Acting alone, tilt the head to the same side – Together, they assist in neck extension Sport Books Publisher 10 Muscles of the Pectoral Girdle Sport Books Publisher 11 Muscles acting to hold the pectoral girdle to the chest wall: Anterior – – – – Pectoralis Major Pectoralis Minor Subclavius Serratus Anterior Posterior – – – – – Trapezius Latissimus Dorsi Levator Scapulae Rhomboids Major Rhomboids Minor Sport Books Publisher 12 Pectoral Girdle - Anterior Pectoralis Major Pectoralis Minor Serratus Anterior Sport Books Publisher 13 Pectoral Girdle - Posterior Trapezius (upper fibres) Trapezius (middle fibres) Rhomboids Trapezius (lower fibres) Latissimus Dorsi Sport Books Publisher 14 Muscles which attach from the scapula to the humerus, and act across the shoulder joint: Anterior – Subscapularis Posterior – – – – Supraspinatus Infraspinatus Teres Minor Teres Major Lateral – Deltoid Sport Books Publisher 15 Anterior Lateral Deltoid (anterior fibres) Subscapularis Deltoid (middle fibres) Deltoid (posterior fibres) Sport Books Publisher 16 Superior and Posterior Supraspinatus Infraspinatus Teres Minor Teres Major Sport Books Publisher 17 Muscles of the Arm Sport Books Publisher 18 Anterior Compartment Biceps Brachii – Attaches • proximally to distal part of humerus (short head) Biceps Brachii • distally to proximal part of ulna (together with long head) – movements of the arm: • flexor of the elbow joint • supinator of the forearm Sport Books Publisher 19 Anterior Compartment Cont’d Brachialis – Attaches • proximally to the anterior surface of the humerus • distally to the coronoid process of the ulna Brachialis – movements of the arm • powerful flexor of the elbow joint • it works along with the biceps brachii. Sport Books Publisher 20 Posterior Compartment Triceps Brachii – Attaches • Proximaslly to humerus (medial and lateral head) • Distally to the olecranon process of the ulna(together with long head) Triceps – Movement of the arm: • elbow extensor Sport Books Publisher 21 Muscles of the Forearm Sport Books Publisher 22 forearm muscles act on the elbow, wrist and digits (fingers) flexor-pronator group – attached to the medial epicondyle of the humerus extensor-supinator – attached to the lateral epicondyle of the humerus Sport Books Publisher 23 Flexors of the forearm Extensors of the forearm Posterior View Anterior View Sport Books Publisher 24 Muscles of the Pelvic Girdle Sport Books Publisher 25 Anterior Muscles Iliopsoas Sport Books Publisher 26 Posterior and Lateral Muscles gluteals – include 3 muscles: Gluteus Medius • gluteus maximus – the largest of the three muscles – principal extensor of the hip Gluteus Maximus • Gluteus medius and minimus – assist it in hip extension – abduct the hip lateral or external rotators of the hip – six little muscles Sport Books Publisher 27 Thigh Muscles Sport Books Publisher 28 Medial Compartment Pectineus gracilis Adductors: Pectineus Adductor Brevis Adductor Longus – adductor longus – adductor brevis – adductor magnus Adductor Magnus Gracilis primary action adduct the thigh towards the midline Sport Books Publisher 29 Anterior Compartment Sartorius Quadriceps – – – – Sartorius rectus femoris vastus lateralis vastus intermedius vastus medialis. Rectus Femoris Vastus Lateralis Vastus Intermedius Extend at the knee Sartorius and Rectus femoris also flex at the hip Sport Books Publisher Vastus Medialis 30 Posterior Compartment Hamstrings – biceps femoris – semitendinosus – semimembranosus attach – proximally to the ischial tuberosity – distally, biceps femoris to the head of the fibula and the semitendinosus and semimembranosus to the tibia. Long Head of Biceps Femoris Short Head of Biceps Femoris Semitendinosis Semimembranosis flex the knee also extend at the hip Sport Books Publisher 31 Leg Muscles Sport Books Publisher 32 Anterior Compartment tibialis anterior extensor hallucis longus (deep) extensor digitorum (deep) arise from – anterolateral surface of the tibia – interosseous membrane between the tibia and the fibula – anterior surface of the fibula cross anterior to the ankle joint Tibialis Anterior attach distally to – medial side of the foot – distal phalanges of the digits movements: – primarily dorsi-flexors of the ankle – extensors of the toes – Tibialis anterior further inverts the foot – Peroneus tertius assist in eversion Sport Books Publisher 33 Lateral Compartment peroneus longus peroneus brevis proximaly attach to the lateral surface of the tibia Peroneus Longus pass behind the lateral malleolus distally attach to the foot movement Peroneus Brevis – plantar flexors – everters of the sole of the foot Sport Books Publisher 34 Posterior Compartment Superficial group – Gastrocnemius • has two proximal heads • proximally attaches to the medial and lateral epicondyles of the distal femur – Soleus • proximally attaches to head proximal ends of tibia and fibula – gastroc and soleus come together to form an Achilles tendon – principal plantar flexors of the ankle Gastrocnemius Soleus Achilles Tendon Sport Books Publisher 35 Posterior Compartment Deep group – primary role is flexion of the toes – assist in plantar flexion of the ankle Sport Books Publisher 36 Muscles of the Abdomen Sport Books Publisher 37 Obliques external oblique Internal oblique internal oblique transversus abdominus reach from the vertebral column, ribs, and hip bone posteriorly meet in the midline anteriorly through rectus abdominus functions: – lateral bending of the abdomen – rotation of the abdomen – extension of the abdomen during forced inspiration – allow the development of a pregnant uterus – contract to help expel fecal contents from the rectum Sport Books Publisher External oblique Transversus abdominus 38 Rectus Abdominus Rectus Sheath Paired midline muscles Powerful flexor of the anterior abdominal wall Strengthening of the abdominal muscles is a very important part of back therapy, because the abdominals act to support the back. Rectus Abdominis Sport Books Publisher Linea alba 39