Lecture 3: Joints, Muscles and Nerves PDF

Faculty of Physiotherapy Anatomy 1 Joints, Muscles and Nerves By Dr. Hagar Yousry Rady Associate Professor of Anatomy and Embryology  Intended Learning Objectives (ILOs): By the end...

Faculty of Physiotherapy Anatomy 1 Joints, Muscles and Nerves By Dr. Hagar Yousry Rady Associate Professor of Anatomy and Embryology  Intended Learning Objectives (ILOs): By the end of this lecture, the student should be able to identify the following : 1. Identify types of joints 2. Describe synovial joints 3. Identify types of muscles 4. Describe structure of spinal nerves The Joints  The Joints A joint is a meeting of (two bones or more) OR a (bone and cartilage). They are classified according to the connecting element into: 1. Fibrous 2. Cartilaginous 3. Synovial  1. The Fibrous Joints Bones are connected by fibrous tissue The are classified into: Suture: Syndesmosis: Gomphosis: Bones joined by sutural ligaments Joined by interosseous ligament Joint between tooth & Sutures of skull Inferior tibiofibular joint mandible or maxilla Allow no movement Allow little movement Movement is pathological 2. The Cartilaginous Joints Bones are united by Hyaline cartilage :as in primary cartilaginous Fibrocartilage : as in secondary cartilaginous The Primary Cartilaginous Joints Joined by hyaline cartilage present in epiphyseal plate. Ribs &costal cartilage. Joints usually ossify  The Secondary Cartilaginous Joints A layer of hyaline cartilage covers the surface of the bones United by fibrocartilage Slightly movable Present in the mid-line of the body: ✓Symphysis pubis ✓Between vertebral bodies ✓Sternum  The Synovial Joints Most common type Bones are covered by hyaline cartilage Bones are separated by joint cavity Cavity is surrounded by fibrous capsule Capsule is lined by synovial membrane Capsule is supported by ligaments Joints might contain: ligaments, cartilage, tendons  Classification of Synovial Joints Synovial joints are classified according to number of axes Multi-axial Uniaxial Biaxial (Poly-axial)  Uniaxial Synovial Joints Hinge: Pivot: Along horizontal axis A central bony pivot is surrounded They allow flexion & extension by a bony ring Elbow joint Rotation movement around vertical axis ✓Superior radioulnar joint ✓ Atlantoaxial joint.  Biaxial Synovial Joints Saddle: Ellipsoid: ✓ Carpometacarpal of thumb ✓ Wrist joint ✓ Allow flexion , extension ✓ flexion & extension ✓ Adduction & abduction ✓ adduction& abduction ✓ Slight rotation ✓ No rotation Polyaxial Synovial Joints 1)Ball and socket: Allow all movements Shoulder joint& hip joint Hip Femur  Factors supporting joints ❑ Shape of articulating bones ❑ Supporting ligament ❑ Tone of surrounding muscles Muscular System  The Muscles Muscles are classified into Skeletal muscles: Smooth muscles: Cardiac muscles: ▪ Voluntary ▪ Involuntary ▪ Involuntary& capable of rythmic ▪ main bulk ,muscles of limbs ▪ Like muscles of GIT, urinary contractions ▪ rapid contractions bladder, uterus & blood vessels ▪ Controlled by autonomic nervous system. ▪ Controlled by autonomic nervous system or hormonal  Classification according to shape & line of pull 1- Parallel Fibers wide range of movement & less force 1- Quadrilateral: 2- Fusiform: 3- Strap: 3- Strap like with tendinous Biceps Sartorius intersections: Quadratus lumborum Rectus abdominus Biceps  2- Oblique Fibers Range of movement is less & force is more Either pennate or triangular A- Pennate Fibers B- Triangular Unipennate Bipennate Multipennate Fibers converge from wide attachment to narrow tendon – Fibers on both sides of series of bipennate Flexor pollicis longus tendon Temporalis Deltoid Dorsal interossei  3- Cruciate Fibers 4- Circular Fibers Muscle fibers made of 2 planes Forms complete circle which run in different directions Orbicularis oculi Sternomastoid 1 2 II- Way of attachment of skeletal muscles Raphe: Fibrous band separates Fleshy fibers flesh muscle from each other Tendon: Aponeurosis: A long fibrous A flat fibrous sheet cord 21 21  I- Attachment of skeletal muscles The proximal attachment of the muscle is called “origin”. The distal attachment of the muscle is called “insertion”. A muscle can act from either its origin or insertion according to the needed movement. 22 22 23  Actions of muscles Prime mover: initiate movement Antagonist: antagonize movement Synergist: prevent unwanted movements The Nervous System  Divisions of the Nervous System Central Nervous System Peripheral Nervous System (CNS) (PNS) Autonomic Nervous Somatic Nervous System System (ANS) 26  Central Nervous Somatic Nervous Autonomic Nervous System system System Includes: Includes: Includes : - The Brain. - 12 pairs of cranial nerves. - Sympathetic system. - The Spinal cord. - 31 pairs of spinal nerves. - Parasympathetic system. - +their associated ganglia. Carries sensation and It controls the smooth controls the skeletal muscles, heart, and the muscles glands 27  The Brain The brain is formed of: 1- Cerebrum 2- Brain stem 3- Cerebellum 28 The cord is divided into segments (31 segments) giving rise to 31 pairs of spinal nerves: A- Cervical segments : 8 B- Thoacic segments: 12. C- Lumbar segments: 5. D- Sacral segments: 5. E- Single coccygeal segment. 29 Peripheral nervous system 12 cranial nerves