Muscles of the Torso and Limbs

1. Muscles of the Torso and Limbs • Naming Conventions • Head and Neck Muscles Trunk Muscles • Muscles of the Upper Arm • Muscles of the Lower Arm and Hand • Muscles of the Hip and Upper Leg • Muscles of Lower Leg and Foot

2. Types of Muscles (By Function) • Prime mover – muscle with the major responsibility for a certain movement • Antagonist – muscle that opposes or reverses a prime mover • Synergist – muscle that aids a prime mover in a movement and helps prevent rotation The biceps and triceps are antagonists

3. Naming Conventions of Skeletal Muscles • Direction of muscle fibers • Example: rectus (straight) • Relative size of the muscle • Example: maximus (largest) • Location of the muscle • Example: many muscles are named for bones (e.g., temporalis) • Number of origins • Example: triceps (three heads) • Location of the muscle’s origin and insertion • Example: sterno (on the sternum) • Shape of the muscle • Example: deltoid (triangular) • Action of the muscle • Example: flexor and extensor (flexes or extends a bone)

4. Head and Neck Muscles Occipitofrontalis (epicranius) Frontal belly (o:gal apo, i: skin eyebrws, nose) (Galea aponeurotica) Corrugator supercilii Orbicularis oculi (o:frntl, max bones, i: tissue eyeld) Occipital belly (o:occ & temprl, i: gal apon) Levator labii superioris Zygomaticus major (o:zyg arch & bone, i: ramus mand) (o:manub stern, med clav, i: mast proc temprl) Posterior belly Depressor labii inferioris Digastric Anterior belly Splenius capitus

5. External Intercostal (o:inf brdr rib above, i: sup brdr rib below ) Inspiration muscles (a) Internal Intercostal (o:sup bord rib below, i: inf bord rib abv ) Expiration muscles Figure 10.10a

6. Clavicle Sternum Serratus anterior Humerus Scapula-rotating, arm raising muscle (a) Figure 10.13a

7. Trunk Muscles Pectoralis minor Diaphragm (o:pub crst & symph, i: xiph proc stern & cost carts ) Pectoralis major (o:stern end clav, stern, cost cart, i: grtr tubcle hum & intrtub sulc) Internal (o:sup bord rib below, i: inf bord rib abv ) and external (o:inf brdr rib above, i: sup brdr rib below ) intercostals Anterior views of trunk Figure 6.16

8. Deep Trunk and Arm Muscles Supraspinatus (o:supsp foss scap, i: grtr tubcle hum ) Levator scapulae Rhomboid major Splenius capitus Infraspinatus (o:lat clav, acrom & spine scap, I: delt tuber hum ) Teres major (o:lmbr vert,ilc crst, i: intertub sulc hum ) Posterior views of trunk

9. Clavicle Deltoid Sternum Pectoralis major Triceps brachii: (o:post shaft humerus, lat border by glen cav scap, i: olecranon process) Lateral head Long head Medial head Biceps brachii (o:cor proc scap, top glen foss, intertub sulc hum; I: radial tub hum) Brachialis Brachioradialis (a) Anterior view Figure 10.14a

10. Supraspinatus* Spine of scapula Deltoid (cut) Greater tubercle of humerus Infraspinatus* Teres major Triceps brachii: Lateral head Long head Latissimus dorsi Humerus Olecranon process of ulna (b) Posterior view Figure 10.14b

11. Flexor digitorum superficialis Flexor pollicis longus Flexor carpi ulnaris Flexor carpi radialis (o:medl epicond hum; I: base 2nd,3rd metcpls) Brachioradialis Medial epicondyle of humerus Tendon of biceps brachii Medial head of triceps brachii Biceps brachii (a) Figure 10.15a

12. Tendons of extensor digitorum Tendons of extensor carpi radialis brevis and longus Extensor pollicis longus Extensor carpi ulnaris Extensor digitorum Flexor carpi ulnaris Extensor carpi radialis brevis (o:lat epicon hum; I: base 3rd metacpl) Insertion of triceps brachii Brachioradialis (a) Figure 10.16a

13. Muscles of the Torso and Limbs Naming Conventions Head and Neck Muscles Trunk Muscles Muscles of the Upper Arm Muscles of the Lower Arm and Hand Muscles of the Hip and Upper Leg Muscles of Lower Leg and Foot

14. 12th thoracic vertebra 12th rib Iliac crest Anterior superior iliac spine 5th lumbar vertebra Psoas major Illiopsoas Illiacus Sartorius (o:ant sup ilc spine; i: med. prox. tibia) Adductor longus Gracilis Quadriceps femoris (o:ant & lat thigh; i: patella & tib tuber.) • Rectus femoris (o:ant inf ilc spine & sup acetab; I: pat & tib tuber) • Vastus lateralis (o:greater trocantr fmr; I: patella & tib tuber) Tendon of quadriceps femoris • Vastus medialis (o:intertroch line fmr; I: patella & tib tuber Patella Patellar ligament (a) Figure 10.19a

15. Gluteus medius Gluteus maximus (o:dors illm, sacrm,coxcy, i: gluteal tuber fmr & tibia)) Gracilis Long head Biceps femoris Short head Hamstrings Semitendinosus Semimembranosus (a) Figure 10.20a

16. Gluteus medius Gluteus maximus Gracilis Long head Biceps femoris Short head Hamstrings Semitendinosus Semimembranosus (a) Figure 10.20a

17. Fibularis longus Gastrocnemius (o:med. & lat. condyles fmr; i: post. calcan.) Tibia Tibialis anterior Extensor digitorum longus Soleus Extensor hallucis longus Fibularis tertius (a) Figure 10.21a

18. Muscles of the Lower Leg (o:med. & lat. condyles fmr; i: post. calcan.)

19. Patella Head of fibula Gastrocnemius (o:med. & lat. condyles fmr; i: post. calcan.) Soleus Fibularis longus Extensor digitorum longus Tibialis anterior Extensor hallucis longus Flexor hallucis longus (o:mid shaft fibula; i: under foot to dist phalx toe) Extensor hallucis brevis Lateral malleolus (a) 5th metatarsal Figure 10.22a

20. Muscles of the Torso and Limbs Naming Conventions Head and Neck Muscles Trunk Muscles Muscles of the Upper Arm Muscles of the Lower Arm and Hand Muscles of the Hip and Upper Leg Muscles of Lower Leg and Foot