Musculoskeletal Anatomy and Physiology PDF

Musculoskeletal Anatomy and Physiology For CAST Technician Program Students Dr Amr Waked Muscular System Overview Types of Muscles: 1.Skeletal Muscle 2.Cardiac Muscle 3.Smooth Muscle  Skeletal Muscle Location: Attached to bones...

Musculoskeletal Anatomy and Physiology For CAST Technician Program Students Dr Amr Waked Muscular System Overview Types of Muscles: 1.Skeletal Muscle 2.Cardiac Muscle 3.Smooth Muscle  Skeletal Muscle Location: Attached to bones Control: Voluntary Appearance: Striated Function: Movement, posture, heat production Characteristics of Muscle Tissue: Excitability: ability to respond to stimuli Contractility: ability to shorten and generate force Extensibility: ability to be stretched without being damaged Elasticity: ability to return to original shape after stretching or contracting  Smooth Muscle Location: Found in the walls of hollow organs (e.g., intestines, blood vessels, bladder). Control: InVoluntary Appearance: Non-striated, spindle-shaped cells. Function: Responsible for slow, sustained contractions such as moving food through the digestive tract (peristalsis) regulating blood vessel diameter (vasoconstriction). Regeneration: Capable of regenerating after injury, unlike skeletal muscle.  Cardiac Muscle Location: Found in the heart only Control: involuntary Appearance: Striated muscle tissue with branched fibers. Function: Responsible for pumping blood throughout the body. Special Features: Automaticity: Can generate its own electrical impulses (pacemaker activity). High endurance and resistance to fatigue.  Skeletal Muscle Anatomy Structure: A- Muscle Fibers: 1. Long, cylindrical cells 2. Multinucleated 3. Enclosed by the sarcolemma (cell membrane) B- Myofibrils: 1. Bundles of protein filaments within muscle fibers 2. Composed of repeating units called sarcomeres C- Sarcomeres: 1. The basic functional unit of muscle fibers 2. Consists of actin (thin) and myosin (thick) filaments 3. Arranged in a striated pattern 4. Z-lines mark the boundaries of each sarcomere Skeletal Muscle (Cont’d) Skeletal Muscle (Cont’d) Types of Muscle Fibers Slow-Twitch (Type I) Fibers: (SR1) Characteristics: Red in color due to high myoglobin content Rich in mitochondria Fatigue-Slowly Generate less force but more sustain activity Function: Endurance activities such as long-distance running Types of Muscle Fibers (cont’d) Fast-Twitch (Type II) Fibers: (FP2) Characteristics: White or pale in color due to lower myoglobin content Fewer mitochondria Fatigue Rapidly Generate more force but less sustain activity Function: Power activities such as weightlifting  Muscle Shapes 1. Parallel Muscles: Fibers run parallel to the long axis of the muscle 2. Fusiform Muscles: Spindle-shaped with a central belly that tapers to tendons on each end 3. Pennate Muscles: Fibers are arranged obliquely to the central tendon Subtypes: Unipennate: Fibers on one side of the tendon Bipennate: Fibers on both sides of the tendon Multipennate: Multiple tendons with fibers obliquely arranged 4. Convergent (Triangular) Muscles: Broad origin with fibers converging to a single tendon 5. Circular Muscles: Fibers arranged concentrically around an opening  Muscle action Agonist: When muscle contract to produce the desired movement e.g.: during flexion of the elbow , biceps muscle considered agonist Antagonist: When agonist muscle contract, the antagonist will relax to allow smooth movement e.g.: during flexion of elbow, Biceps (Agonist) contract but Triceps (antagonist) will relax Synergist: When group of muscle produce the desired movement e.g.: flexion and extension of wrist  Muscle action (cont’d) Isotonic Contraction: It is muscle contraction in which length of muscle changes without increase in tension e.g.: Lifting weights, push-ups, pull-ups Isometric Contraction: It is muscle contraction in which length of muscle remain constant but tension is increase e.g.: trying to lift heavy weight (but weight actually not lifted)  Muscle action (cont’d) Concentric Contraction: It is type of muscle contraction in which muscles shorten while it generating force e.g.: lifting of weight toward shoulder , biceps contract to flex elbow Eccentric Contraction: It is type of contraction in which muscle elongated while it generating force but resistance greater than force generated e.g.: controlled lowering of heavy weight Muscle action (cont’d)  Skeletal Muscle Physiology Muscle Contraction: (Sliding Filament Theory) Muscle contraction occurs when actin (thin filaments) and myosin (thick filaments) slide on each other, lead to shortening of sarcomere and thus the muscle.  Sliding Filament Theory Steps: Resting State: Myosin binding sites on actin are covered by tropomyosin. Action Potential travels till the neuromuscular junction  Acetylcholine Release into the synaptic cleft  Binding of Acetylcholine to receptors on the muscle fiber's sarcolemma  Depolarization of the sarcolemma, initiating an action potential in the muscle fiber  Calcium Release  binding of Calcium to troponin, cause displacement of tropomyosin and exposes myosin binding sites on actin  Cross-Bridge Formation between Myosin heads and actin  Power Stroke Myosin heads pulling actin filaments toward the center of the sarcomere lead to shorting Acetylcholine Breakdown: Acetylcholinesterase breaks down acetylcholine in the synaptic cleft, ending the signal and allowing the muscle to relax.  Connective Tissues * Definition: - It is the tissue that supports, connects, or separates different types of tissues and organs in the body. * Composition: - It consists of cells embedded in an extracellular matrix and ground substance. * Function: - Connective tissue provides structural and metabolic support for other tissues and organs.  Connective Tissues (Cont’d) Types: A- Tendons 1. Connect muscles to bones 2. Provide stability and transmit force for movement B-Ligaments 1. Connect bones to other bones 2. Provide joint stability and limit excessive movement C-Cartilage 1. Flexible, rubbery tissue 2. Reduce the frictions ,cushions joints and allows smooth movement 3. Types: Hyaline (articular), Fibrocartilage (intervertebral discs), Elastic (ear)  Tendons Definition: Tendons are strong, fibrous connective tissues that connect muscles to bones. Structure: Composed primarily of collagen fibers arranged in parallel bundles for strength. Tendon sheaths and synovial fluid reduce friction during movement. Function: Transmit the force generated by muscles to bones, enabling movement. Provide stability to joints by reinforcing their structure. Healing and Repair: Tendons have a limited blood supply, leading to slower healing compared to muscles.  Ligaments Definition: Tough, elastic bands of connective tissue that connect bones to other bones. Structure: Made primarily of collagen fibers, which provide flexibility and strength. Ligaments are slightly elastic, allowing for some stretch while maintaining joint stability. Function: Stabilize and support joints by preventing excessive movement. proprioceptive function that help in balance and coordination. Injury and Healing: Ligaments have a limited blood supply, leading to slow healing power. Common injuries include ACL tears, ankle sprains, and shoulder dislocations.  Definition: Cartilage a flexible, rubbery connective tissue. Structure: Composed of chondrocytes (cartilage cells) embedded in a matrix of collagen and proteoglycans. Lacks blood vessels and nerves; nourished by diffusion from surrounding tissues. Types of Cartilage: Hyaline Cartilage: Most common type; articular cartilage. Elastic Cartilage: More flexible; found in the ear. Fibrocartilage: Tough and dense; found in intervertebral discs and menisci. Function: Provides smooth surfaces for joint movement (reduces friction). Absorbs shock in joints. Supports and maintains the shape of soft tissues. Injury and Healing: Cartilage is avascular so it has limited capacity for repair Cartilage injuries or tears lead to degeneration of articular cartilage (osteoarthritis).  MUSCULOSKELETAL ANATOMY AND PHYSIOLOGY  Regional Anatomy Key Regions: Lower limb 1.Hip Region: Composed of the pelvis and the hip joint. 2.Thigh: Contains the femur, the longest bone in the body. 3.Knee Region: A hinge joint formed by the femur, tibia, and patella. 4.Leg: Comprised of the tibia (weight-bearing bone) and fibula (supportive bone). 5.Ankle: hinge joint Connects the leg to the foot and includes the tibia, fibula, and talus. 6.Foot: Includes tarsal bones, metatarsals, and phalanges.  Lower limb (Cont’d) Functions of the Lower Limb: Mobility: essential for walking, running, jumping, and other movements. Weight-bearing: it support the weight of the body. Balance and Posture: during movement and while standing. Shock Absorption: it absorbs and distributes forces during movement.  1-Pelvic Girdle The pelvic girdle, also known as the bony pelvis, connects the spine to the lower limbs. Pelvis is formed by the fusion of three bones on each side: ilium, ischium, and pubis. Its function is weight transfer and support. Structure: Ilium Ischium Pubis Acetabulum  Pelvic Girdle (Cont’d) Function: 1.Support and Weight Bearing: 1. The pelvic girdle supports the weight of the upper body when sitting and standing. 2. It transfers weight from the axial skeleton to the lower limbs during movement. 2.Protection of Organs: such as the bladder, reproductive organs, and parts of the digestive tract. 3.Attachment for Muscles: 1. Provides attachment points for muscles of the lower limb, abdomen, and pelvic floor. 2. Important for movements like walking, running, and lifting. 4.Stabilization: The sacroiliac joints and ligaments it is the connection between the pelvis and the vertebral column. 5.Childbirth (in females): the female pelvis has wider pelvic inlet and outlet allow for childbirth.  1-Hip joint A-Structure: (ball-and-socket - synovial joint ) Articulation: between the head of the femur (ball) and the acetabulum of the pelvis (socket). Acetabulum: Deep, cup-shaped socket formed from fusion of the ilium, ischium, and pubis. Contains the acetabular labrum, a ring of cartilage that deepens the socket and added stability. Femoral Head: The rounded head of the femur fits into the acetabulum. Synovial Membrane: The hip joint is surrounded by a synovial membrane that produces synovial fluid for lubrication. 1-Hip joint (Cont’d) B-Stability: C-Movements: Ligaments Flexion. Extension. Joint Capsule Abduction. Labrum Adduction. Muscle Support Rotation (Internal and External). Circumduction Any muscle Origin Insertion Nerve supply action Origin Insertion Proximal attachment of the muscle Distal attachment of the muscle Fixed during muscle contraction Movable during muscle contraction Origin has mainly muscle mass Insertion mainly has tendon 1-Hip joint (Cont’d) D-Muscle and action: D-1- Hip Abductors: a. Gluteus Medius b. Gluteus Mimimus c. Tensor Facia Lata Innervation for all : Superoir Gluteal n.  D-1- Hip Abductors (Cont’d): Gluteus Medius: Origin: The outer surface of the ilium, just below the iliac crest. Insertion: Lateral aspect of the greater trochanter of the femur. Function: Primary abductor of the hip; stabilizes the pelvis during gait (prevents the opposite side from dropping). Gluteus Minimus: Origin : Deep to the gluteus medius, also on the outer surface of the ilium. Insertion: Anterior part of the greater trochanter of the femur. Function: Assists the gluteus medius in hip abduction and internal rotation. Tensor Fasciae Latae (TFL): Origin : Anterior part of the iliac crest and the outer surface of ASIS. Insertion: Blends into the iliotibial (IT) band, which inserts into the lateral aspect of the tibia. Function: Assists in hip abduction, flexion, and internal rotation; helps stabilize the hip and knee via the IT band.  D-1- Hip Abductors (Cont’d): Function: Hip Abduction Pelvic Stabilization: During walking or running, the hip abductors stabilize the pelvis to prevent it from dropping on the opposite side (Trendelenburg gait). Posture Maintenance: They contribute to maintaining an upright posture and balance, particularly when standing on one leg. D-Muscle and action:(Cont’d) D-2- Hip Adductors: Adductor Longus Adductor Brevis Adductor Magnus Gracilis Pectineus Innervation for all : Obturator n. Except pectineus Femoral n.  Adductor Longus: Origin: from the pubis D-2- Hip Adductors (Cont’d): Insersion: into the middle third of the linea aspera on the femur. Function: Adducts and medially rotates the thigh. Adductor Brevis: Origin: from the pubic bone Insertion into the proximal part of the linea aspera. Function: Adducts the thigh and assists in flexion and medial rotation. Adductor Magnus: Origin: from the inferior pubic ramus,. Insertion: into the linea aspera,. Function: Adducts the thigh. Gracilis: Origin from the pubis Insertion into the medial surface of uppertibia (part of the pes anserinus group). Function: Adducts the thigh and aids in knee flexion. Pectineus: Origin from the superior ramus of the pubis Insertion into the pectineal line of the femur. Function: Adducts, flexes, and medially rotates the thigh D-Muscle and action:(Cont’d) D-3- Hip Flexors: Iliopsoas (Iliacus + Psoas Major) Rectus Femoris Sartorius Pectineus Innervation for all : Femora n. Except Psoas Major: lumber plexus  Iliopsoas: D-2- Hip Flexors (Cont’d): Iliacus: Origin: from the iliac fossa Insertion into the lesser trochanter of the femur. Function: Flexes and externally rotates the hip. Psoas Major: Origin from the lumbar vertebrae (L1-L5) Insertion into the lesser trochanter. Function: Powerful hip flexor, assists in maintaining posture. Rectus Femoris: Origin : from the anterior inferior iliac spine (AIIS) Insertion into the tibial tuberosity via the patellar tendon. Function: Flexes the hip and extends the knee. Sartorius: Origin from the anterior superior iliac spine (ASIS) Insen into the medial surface of the tibia (part of the pes anserinus group). Function: Flexes, abducts, and externally rotates the hip; flexes the knee. Pectineus: Discussed before D-Muscle and action:(Cont’d) Innervation for all : Sciatic n. Except Gluteus Maximus by Inferior Gluteal n. D-4- Hip Extensors: Gluteus Maximus Hamstring Muscles: Biceps Femoris (Long Head) Semitendinosus Semimembranosus  Gluteus Maximus: D-2- Hip Extensors (Cont’d): Origin: from the ilium, sacrum, and coccyx, Insertion: into the gluteal tuberosity of the femur and the iliotibial (IT) band. Function: hip extension; also assists in external rotation and stabilization of the hip joint. Hamstring Muscles: Biceps Femoris (Long Head): Origin: from the ischial tuberosity Insertion: into the head of the fibula. Function: hip extension and knee flexion. Semitendinosus: Origin: from the ischial tuberosity Insertion into the medial surface of the tibia. Function: Extends the hip and flexes the knee Semimembranosus: Origin: from the ischial tuberosity Insertion into the medial condyle of the tibia. Function: Extends the hip and flexes the knee  2- Knee joint A-Structure: (Hinge - synovial joint ) It is formed by articulation between the femur, tibia and patella. Articular Cartilage: Covers the ends of the femur and tibia, as well as the underside of the patella, reducing friction and absorbing shock. Menisci: Two crescent-shaped cartilages (medial and lateral menisci) act as shock absorbers and provide stability by deepening the articulation between the femur and tibia.  B- Stability: 1-Knee joint (Cont’d) 1. Ligaments: a) Anterior Cruciate Ligament (ACL). b) Posterior Cruciate Ligament (PCL). c) Medial Collateral Ligament (MCL). d) Lateral Collateral Ligament (LCL). 2. Muscles and Tendons: The quadriceps and hamstring muscles, along with the surrounding tendons, provide dynamic stability to the knee joint by controlling movement and supporting the ligaments. 1-Knee joint (Cont’d) D- Muscles: Extensors: C-Movemnt: Quadriceps Femoris: Primary Movements: Rectus Femoris Vastus Lateralis 1.Flexion. Vastus Medialis 2.Extension. Vastus Intermedius Secondary Movements: Flexors: Medial and Lateral Hamstrings: Biceps Femoris Rotation. Semitendinosus Semimembranosus Gastrocnemius. Sartorius and Gracilis. a- Anterior Cruciate Ligament (ACL): B-1- Ligaments: Anatomy: Location: Runs from the anterior aspect of the tibia to the posterior aspect of the femur. Origin: Anterior intercondylar area of the tibia. Insertion: Posterior part of the medial side of the lateral femoral condyle. Function: Prevents Anterior Translation of the tibia relative to the femur. Stabilizes Rotation: Provides rotational stability, particularly during pivoting movements. Stabilize knee joint during dynamic activities.  B-1- Ligaments (Cont’d): b- Posterior Cruciate Ligament (PCL): Anatomy: Location: Runs from the posterior aspect of the tibia to the anterior aspect of the femur. Origin: Posterior intercondylar area of the tibia. Insertion: Anterior part of the lateral side of the medial femoral condyle. Function: Prevents Posterior Translation of the tibia backward relative to the femur. Provides Rotational Stability by controlling rotational movements  B-1- Ligaments (Cont’d): c- Medial Collateral Ligament (MCL): Anatomy: Location: Runs along the inner side of the knee from the femur to the tibia. Origin: Medial femoral condyle. Insertion: Medial aspect of the tibia, near the tibial plateau. Function: Prevents Valgus Stress: (inward force). d- Lateral Collateral Ligament (LCL): Anatomy: Location: Runs along the outer side of the knee from the femur to the fibula. Origin: Lateral femoral condyle. Insertion: Head of the fibula. Function: Prevents Varus Stress (outward force).  Anatomy of the Meniscus Definition: The menisci are two crescent-shaped pieces of fibrocartilage located in the knee joint, between the femur and tibia. 𝐹𝑜𝑟𝑐𝑒 Pressure = 𝑆𝑢𝑟𝑐𝑒 𝐴𝑟𝑒𝑎 Function: They act as shock absorbers. improve the stability of the knee joint. distribute weight across the knee. Proprioception  Anatomy of the Meniscus (Cont’d) Structure of the Meniscus: Medial Meniscus: Location: Located on the inner side of the knee joint. Shape: C-shaped. Attachment: Firmly attached to the joint capsule and the medial collateral ligament (MCL), making it less mobile and more prone to injury. Lateral Meniscus: Location: Located on the outer side of the knee joint. Shape: O-shaped. Attachment: loosely attached to the tibia and lateral collateral ligament (LCL), which gives it more flexibility and reduces its susceptibility to injury.  Anatomy of the Meniscus (Cont’d) Zones of the Meniscus: Red Zone: The outer third of the meniscus. Blood Supply: Well-vascularized, which good healing potential. Red-White Zone: The middle third of the meniscus. Blood Supply: Partially vascularized, meaning some healing potential. White Zone: The inner third of the meniscus. Blood Supply: Avascular (no direct blood supply), with poor healing potential. D-Muscle and action: 1- Knee Extensors: (Quadriceps Femoris) Rectus Femoris Vastus Lateralis Vastus Medialis Vastus Intermedius Innervation for all : Femoral n. D-1- Knee Extensors: (Cont’d) Innervation for all : Femoral n. Rectus Femoris: Origin: Anterior inferior iliac spine (AIIS) and the superior part of the acetabulum. Insertion: Patella via the quadriceps tendon, then to the tibial tuberosity via the patellar ligament. Function: In addition to knee extension, it assists in hip flexion due to its origin on the pelvis. D-1- Knee Extensors: (Cont’d) Vastus Lateralis: Origin: Greater trochanter and the lateral lip of the linea aspera of the femur. Insertion: Patella via the quadriceps tendon, then to the tibial tuberosity via the patellar ligament. Function: knee extension.  D-1- Knee Extensors: (Cont’d) Vastus Medialis: Origin: Intertrochanteric line and the medial lip of the linea aspera of the femur. Insertion: Patella via the quadriceps tendon, then to the tibial tuberosity via the patellar ligament. Function: knee extension and stabilizing the patella  D-1- Knee Extensors: (Cont’d) Vastus Intermedius: Origin: Anterior and lateral surfaces of the femoral shaft. Insertion: Patella via the quadriceps tendon, then to the tibial tuberosity via the patellar ligament. Function: knee extension.  D-Muscle and action: (Cont’d) 1- Knee Flexors: Hamstrings Group (Sciatic n) Biceps Femoris Semitendinosus Semimembranosus Gracilis (Obturator n.) Sartorius (Femoral n) Gastrocnemius (Tibial n.) Popliteus (Tibial n.) D-2- Knee Flexors: (Cont’d) Gastrocnemius: Origin: Medial and lateral condyles of the femur. Insertion: Calcaneus via the Achilles tendon. Function: Plantarflexion of the ankle help in knee flexion.  D-2- Knee Flexors: (Cont’d) Popliteus: Origin: Lateral condyle of the femur. Insertion: Posterior surface of upper tibia. Function: Unlocks the knee by initiating flexion and medially rotates the tibia on the femur (or laterally rotates the femur on the tibia).  MUSCULOSKELETAL ANATOMY AND PHYSIOLOGY For Cast Technician Program Students Dr Amr Waked  2- Knee joint A-Structure: (Hinge - synovial joint ) It is formed by articulation between the femur, tibia and patella. Articular Cartilage: Covers the ends of the femur and tibia, as well as the underside of the patella, reducing friction and absorbing shock. Menisci: Two crescent-shaped cartilages (medial and lateral menisci) act as shock absorbers and provide stability by deepening the articulation between the femur and tibia.  2-Knee joint (Cont’d) B- Stability: 1. Ligaments: a) Anterior Cruciate Ligament (ACL). b) Posterior Cruciate Ligament (PCL). c) Medial Collateral Ligament (MCL). d) Lateral Collateral Ligament (LCL). 2. Muscles and Tendons: The quadriceps and hamstring muscles, along with the surrounding tendons, provide dynamic stability to the knee joint by controlling movement and supporting the ligaments. 2-Knee joint (Cont’d) C-Movement: D- Muscles: Primary Movements: Extensors: 1.Flexion. Quadriceps Femoris: Rectus Femoris 2.Extension. Vastus Lateralis Secondary Movements: Vastus Medialis Vastus Intermedius Medial and Lateral Rotation. Flexors: Hamstrings: Biceps Femoris Semitendinosus Semimembranosus Gastrocnemius. Sartorius and Gracilis.  B-1- Ligaments: a- Anterior Cruciate Ligament (ACL): Anatomy: Location: Runs from the anterior aspect of the tibia to the posterior aspect of the femur. Origin: Anterior intercondylar area of the tibia. Insertion: Posterior part of the medial side of the lateral femoral condyle. Function: Prevents Anterior Translation of the tibia relative to the femur. Stabilizes Rotation: Provides rotational stability, particularly during pivoting movements. Stabilize knee joint during dynamic activities.  B-1- Ligaments (Cont’d): b- Posterior Cruciate Ligament (PCL): Anatomy: Location: Runs from the posterior aspect of the tibia to the anterior aspect of the femur. Origin: Posterior intercondylar area of the tibia. Insertion: Anterior part of the lateral side of the medial femoral condyle. Function: Prevents Posterior Translation of the tibia backward relative to the femur. Provides Rotational Stability by controlling rotational movements  B-1- Ligaments (Cont’d): c- Medial Collateral Ligament (MCL): Anatomy: Location: Runs along the inner side of the knee from the femur to the tibia. Origin: Medial femoral condyle. Insertion: Medial aspect of the tibia, near the tibial plateau. Function: Prevents Valgus Stress: (inward force). d- Lateral Collateral Ligament (LCL): Anatomy: Location: Runs along the outer side of the knee from the femur to the fibula. Origin: Lateral femoral condyle. Insertion: Head of the fibula. Function: Prevents Varus Stress (outward force).  Anatomy of the Meniscus Definition: The menisci are two crescent-shaped pieces of fibrocartilage located in the knee 𝐹𝑜𝑟𝑐𝑒 joint, between the femur and tibia. Pressure = 𝑆𝑢𝑟𝑐𝑒 𝐴𝑟𝑒𝑎 Function: They act as shock absorbers. Improve the stability of the knee joint. Distribute weight across the knee. Proprioception  Anatomy of the Meniscus (Cont’d) Structure of the Meniscus: Medial Meniscus: Location: Located on the inner side of the knee joint. Shape: C-shaped. Attachment: Firmly attached to the joint capsule and the medial collateral ligament (MCL), making it less mobile and more prone to injury. Lateral Meniscus: Location: Located on the outer side of the knee joint. Shape: O-shaped. Attachment: loosely attached to the tibia and lateral collateral ligament (LCL), which gives it more flexibility and reduces its susceptibility to injury.  Anatomy of the Meniscus (Cont’d) Zones of the Meniscus: Red Zone: The outer third of the meniscus. Blood Supply: Well-vascularized, which good healing potential. Red-White Zone: The middle third of the meniscus. Blood Supply: Partially vascularized, meaning some healing potential. White Zone: The inner third of the meniscus. Blood Supply: Avascular (no direct blood supply), with poor healing potential. D-Muscle and action: 1- Knee Extensors: (Quadriceps Femoris) Rectus Femoris Vastus Lateralis Vastus Medialis Vastus Intermedius Innervation for all : Femoral n. D-1- Knee Extensors: (Cont’d) Innervation for all : Femoral n. Rectus Femoris: Origin: Anterior inferior iliac spine (AIIS) and the superior part of the acetabulum. Insertion: Patella via the quadriceps tendon, then to the tibial tuberosity via the patellar ligament. Function: In addition to knee extension, it assists in hip flexion due to its origin on the pelvis. D-1- Knee Extensors: (Cont’d) Vastus Lateralis: Origin: Greater trochanter and the lateral lip of the linea aspera of the femur. Insertion: Patella via the quadriceps tendon, then to the tibial tuberosity via the patellar ligament. Function: knee extension.  D-1- Knee Extensors: (Cont’d) Vastus Medialis: Origin: Intertrochanteric line and the medial lip of the linea aspera of the femur. Insertion: Patella via the quadriceps tendon, then to the tibial tuberosity via the patellar ligament. Function: knee extension and stabilizing the patella  D-1- Knee Extensors: (Cont’d) Vastus Intermedius: Origin: Anterior and lateral surfaces of the femoral shaft. Insertion: Patella via the quadriceps tendon, then to the tibial tuberosity via the patellar ligament. Function: knee extension. D-Muscle and action: (Cont’d) 1- Knee Flexors: Hamstrings Group (Sciatic n) Biceps Femoris Semitendinosus Semimembranosus Gracilis (Obturator n.) Sartorius (Femoral n) Gastrocnemius (Tibial n.) Popliteus (Tibial n.)  D-2- Knee Flexors: (Cont’d) Gastrocnemius: Origin: Medial and lateral condyles of the femur. Insertion: Calcaneus via the Achilles tendon. Function: Plantarflexion of the ankle help in knee flexion.  D-2- Knee Flexors: (Cont’d) Popliteus: Origin: Lateral condyle of the femur. Insertion: Posterior surface of upper tibia. Function: Unlocks the knee by initiating flexion and medially rotates the tibia on the femur (or laterally rotates the femur on the tibia).  Talus  ‫تهاني‬ Calcaneus  ‫كلت‬ Cuboid  ‫كباب‬ Navicular  ‫نيفه‬ Cuneiforms  ‫ كتاكيت‬3  3- Ankle joint A- Structure (Synovial Hing Joint) It formed by articulation of: Tibia (medial malleolus) Fibula (lateral malleolus) Talus (superior surface of talus articulates with tibia and fibula) Tibia and Fibula: Form a socket-like structure called the mortise. Talus: Fits into the mortise, forming the talocrural joint Subtalar Joint: Between the talus and calcaneus, allowing inversion and eversion movements.  3- Ankle joint (Cont’d) B- Stability: Ligaments: a) Medial Deltoid Ligament b) Lateral Ligament Anterior Talofibular Ligament (ATFL) Posterior Talofibular Ligament (PTFL) Calcaneofibular Ligament (CFL) c) Syndesmosis: Inferior Tibio-fibular ligament (ITFL) Anterior inferior tibio-fibular ligament (AITFL) Posterior inferior tibio-fibular ligament (PITFL) 3- Ankle joint (Cont’d) C- Movement : 1. Primary movement: Dorsiflexion Muscles: Plantarflexion Muscles: 2. Secondary movement: (occur at subtalar joint) Eversion Muscles: Inversion Muscles: 3- Ankle joint (Cont’d) D-Muscles : Dorsiflexion Muscles: Eversion Muscles: Tibialis Anterior … Peroneus Longus Extensor Digitorum Longus … Peroneus Brevis Extensor Hallucis Longus … Peroneus Tertius Inversion Muscles: Tibialis Posterior Plantarflexion Muscles: Tibialis Anterior Gastrocnemius Soleus Plantaris Tibialis Posterior … Flexor Digitorum Longus … Flexor Hallucis longus …  D-1- Ankle Dorsiflexors: Innervation for all : Anterior tibial n. Tibialis Anterior: Origin: Lateral condyle and superior half of the lateral surface of the tibia. Insertion: Medial cuneiform and base of the first metatarsal. Function: Primary muscle responsible for dorsiflexion of the foot and inversion.  D-1- Ankle Dorsiflexors: (Cont’d) Innervation for all : Anterior tibial n. Extensor Hallucis Longus: Origin: Middle part of the anterior surface of the fibula and the interosseous membrane. Insertion: Dorsal aspect of the base of the distal phalanx of the big toe. Function: Dorsiflexion of the foot and extension of the big toe.  D-1- Ankle Dorsiflexors: (Cont’d) Innervation for all : Anterior tibial n. Extensor Digitorum Longus: Origin: Lateral condyle of the tibia, superior three-quarters of the anterior surface of the fibula, and interosseous membrane. Insertion: Middle and distal phalanges of the lateral four toes. Function: Dorsiflexion of the foot and extension of the toes.  D-1- Ankle Dorsiflexors: (Cont’d) Innervation for all : Anterior tibial n. Peroneus tertius: (considered part of the extensor digitorum longus) Origin: Distal third of the anterior surface of the fibula and interosseous membrane. Insertion: Dorsum of the base of the 5th metatarsal. Function: Assists in dorsiflexion and eversion of the foot. D-2- Ankle Planter flexors: A. Superficial group: (innervated by medial popliteal n.) Gastrocnemius Soleus Plantaris B. Deep Group: (innervated by posterior tibial n.) Tibialis Posterior Flexor Hallucis Longus Flexor Digitorum Longus  D-2- Ankle Planter flexors: (Cont’d) Superficial group: (innervated by medial popliteal n.) Gastrocnemius: Origin: Two heads originate from the medial and lateral condyles of the femur. Insertion: Calcaneus via the Achilles tendon. Function: Powerful plantar flexor and assists in knee flexion.  D-2- Ankle Planter flexors: (Cont’d) Superficial group: (innervated by medial popliteal n.) Soleus: Origin: Posterior surface of the tibia and fibula. Insertion: Calcaneus via the Achilles tendon (joins with the gastrocnemius). Function: Strong plantar flexor, particularly during standing and walking.  D-2- Ankle Planter flexors: (Cont’d) Superficial group: (innervated by medial popliteal n.) Plantaris: (sometimes absent in some individuals) OriginLateral supracondylar ridge of the femur. Insertion: Calcaneus via a long, thin tendon (which merges with the Achilles tendon).. Function: Assists in plantar flexion and knee flexion.  D-2- Ankle Planter flexors: (Cont’d) Deep group: (innervated by Posterior Tibial n.) Tibialis Posterior: Origin: Posterior surfaces of the tibia, fibula, and interosseous membrane. Insertion: Navicular and medial cuneiform bone. Function: Plantar flexion and inversion of the foot, supports the arch.  D-2- Ankle Planter flexors: (Cont’d) Deep group: (innervated by Posterior Tibial n.) Flexor Hallucis Longus: Origin: Posterior surface of the fibula. Insertion: Base of the distal phalanx of the great toe.. Function: Flexes the great toe and assists in plantar flexion..  D-2- Ankle Planter flexors: (Cont’d) Deep group: (innervated by Posterior Tibial n.) Flexor Digitorum Longus: Origin: Posterior surface of the tibia. Insertion: Bases of the distal phalanges of the lateral four toes. Function: Flexes the toes and assists in plantar flexion  D-3- Ankle Evertors: Innervation for all : Superficial peroneal n. Peroneus Longus: Origin: Head and superior two-thirds of the lateral surface of the fibula. Insertion: Base of the first metatarsal and medial cuneiform. Function: Eversion of the foot and assists in plantar flexion  D-4- Ankle Invertors: Discussed Before Tibialis Anterior: (innervated by Anterior Tibial n.) Tibialis Posterior: (innervated by Posterior Tibial n.)  MUSCULOSKELETAL ANATOMY AND PHYSIOLOGY For Cast Technician Program Students Dr Amr Waked  Talus  ‫تهاني‬ Calcaneus  ‫كلت‬ Cuboid  ‫كباب‬ Navicular  ‫نيفه‬ Cuneiforms  ‫ كتاكيت‬3  3- Foot Regions of the Foot: Hindfoot: Calcaneus and talus. Midfoot: Navicular, cuboid, and three cuneiforms. Forefoot: Metatarsals and phalanges.  3- Foot (Cont’d) Joints of the Foot: Ankle Joint : For dorsiflexion and plantarflexion. Subtalar Joint (between the talus and calcaneus): For inversion and eversion. Transverse Tarsal Joint: For pronation and supination. Metatarsophalangeal Joints: For flexion, extension, and abduction of the toes.  3- Foot (Cont’d) Arches of the Foot: (Tripod) Medial Longitudinal Arch Lateral Longitudinal Arch Transverse Arch  4- Ankle joint A- Structure (Synovial Hing Joint) It formed by articulation of: Tibia (medial malleolus) Fibula (lateral malleolus) Talus (superior surface of talus articulates with tibia and fibula) Tibia and Fibula: Form a socket-like structure called the mortise. Talus: Fits into the mortise, forming the talocrural joint Subtalar Joint: Between the talus and calcaneus, allowing inversion and eversion movements. 4- Ankle joint (Cont’d) Ligaments: a) Medial Deltoid Ligament b) Lateral Ligament Anterior Talofibular Ligament (ATFL) Posterior Talofibular Ligament (PTFL) Calcaneofibular Ligament (CFL) c) Syndesmosis: Inferior Tibio-fibular ligament (ITFL) Anterior inferior tibio-fibular ligament (AITFL) Posterior inferior tibio-fibular ligament (PITFL) 4- Ankle joint (Cont’d) C- Movement : 1. Primary movement: Dorsiflexion Muscles Plantarflexion Muscles 2. Secondary movement: (occur at subtalar joint) Eversion Muscles Inversion Muscles  C- Movement (Cont’d): Dorsiflexion: Movement of foot upwards towards the leg. Supination: ‫تحت – جوه جوه‬ plantarflexion + inversion + adduction, Plantarflexion: where the foot rolls outward. Movement of foot away from the leg. Pronation : ‫ بره‬- ‫فوق – بره‬ Inversion: dorsiflexion + eversion + abduction, Turning the sole of the foot inward where the foot rolls inward. Eversion: Turning the sole of the foot outward 4- Ankle joint (Cont’d) D-Muscles : Dorsiflexion Muscles: Eversion Muscles: Tibialis Anterior … Peroneus Longus Extensor Digitorum Longus … Peroneus Brevis Extensor Hallucis Longus … Peroneus Tertius Inversion Muscles: Tibialis Posterior Plantarflexion Muscles: Tibialis Anterior Gastrocnemius Soleus Plantaris Tibialis Posterior … Flexor Digitorum Longus … Flexor Hallucis longus …  D-1- Ankle Dorsiflexors: Tibialis Anterior: Origin: Lateral condyle and superior half of the lateral surface of the tibia. Insertion: Medial cuneiform and base of the first metatarsal. Function: Primary muscle responsible for dorsiflexion of the foot and inversion.  D-1- Ankle Dorsiflexors: (Cont’d) Extensor Hallucis Longus: Origin: Middle part of the anterior surface of the fibula and the interosseous membrane. Insertion: Dorsal aspect of the base of the distal phalanx of the big toe. Function: Dorsiflexion of the foot and extension of the big toe.  D-1- Ankle Dorsiflexors: (Cont’d) Extensor Digitorum Longus: Origin: Lateral condyle of the tibia, superior three-quarters of the anterior surface of the fibula, and interosseous membrane. Insertion: Middle and distal phalanges of the lateral four toes. Function: Dorsiflexion of the foot and extension of the toes.  D-1- Ankle Dorsiflexors: (Cont’d) Peroneus tertius: (considered part of the extensor digitorum longus) Origin: Distal third of the anterior surface of the fibula and interosseous membrane. Insertion: base of the 5th metatarsal. Function: Assists in dorsiflexion and eversion of the foot. D-2- Ankle Planter flexors: A. Superficial group: (innervated by medial popliteal n.) Gastrocnemius Soleus Plantaris B. Deep Group: (innervated by posterior tibial n.) Tibialis Posterior Flexor Hallucis Longus Flexor Digitorum Longus  D-2- Ankle Planter flexors: (Cont’d) Gastrocnemius: Origin: Two heads originate from the medial and lateral condyles of the femur. Insertion: Calcaneus via the Achilles tendon. Function: Powerful plantar flexor and assists in knee flexion.  D-2- Ankle Planter flexors: (Cont’d) Superficial group: (innervated by medial popliteal n.) Soleus: Origin: Posterior surface of the tibia and fibula. Insertion: Calcaneus via the Achilles tendon (joins with the gastrocnemius). Function: Strong plantar flexor, particularly during standing and walking.  D-2- Ankle Planter flexors: (Cont’d) Plantaris: (sometimes absent in some individuals) OriginLateral supracondylar ridge of the femur. Insertion: Calcaneus via a long, thin tendon (which merges with the Achilles tendon).. Function: Assists in plantar flexion and knee flexion.  D-2- Ankle Planter flexors: (Cont’d) Tibialis Posterior: Origin: Posterior surfaces of the tibia, fibula, and interosseous membrane. Insertion: Navicular and medial cuneiform bone. Function: Plantar flexion and inversion of the foot, supports the arch.  D-2- Ankle Planter flexors: (Cont’d) Flexor Hallucis Longus: Origin: Posterior surface of the fibula. Insertion: Base of the distal phalanx of the big toe. Function: Flexes the great toe and assists in plantar flexion.  D-2- Ankle Planter flexors: (Cont’d) Flexor Digitorum Longus: Origin: Posterior surface of the tibia. Insertion: Bases of the distal phalanges of the lateral four toes. Function: Flexes the toes and assists in plantar flexion  D-3- Ankle Evertors: Peroneus Longus: Origin: Head and superior two-thirds of the lateral surface of the fibula. Insertion: Base of the first metatarsal and medial cuneiform. Function: Eversion of the foot and assists in plantar flexion  D-4- Ankle Invertors: Discussed Before Tibialis Anterior: (innervated by ) Tibialis Posterior: (innervated by ) Blood Supply of lower limb Arterial Venous  External Iliac a. Femoral a. Popliteal a. Ant Tibial a. Post Tibial a. Dorsalis Pedis Peroneal a. Med & lat planter a. Blood Supply of lower limb (Cont’d) Venous system: 1. Superficial a) Great Saphenous Vein b) Small Saphenous Vein 2. Deep a) Femoral Vein b) Popliteal Vein c) Anterior and Posterior Tibial Veins d) Peroneal Veins 3. Perforating veins (connect superficial and deep)  Clinical Importance of Venous Drainage in Cast Application: In Casted limb  Venous Stasis  high risk of DVT Monitoring for signs of venous stasis such as Swelling, pain, and discoloration. elevation of the limb to improves venous return. Early Mobilization improves venous return and prevent DVT Nerve Supply of lower limb:  MUSCULOSKELETAL ANATOMY AND PHYSIOLOGY For Cast Technician Program Students Dr Amr Waked Key Regions: 4.Forearm: 1.Shoulder Joint: Formed by Radius and Ulna. Formed by Articulation of Head of humorous and 5.Wrist Joint: scapula (Glenohumeral). Formed by Articulation of Radius and Ulna with 2.Arm: Carbal bone. Contains the Humorous. 6.Hand: 3.Elbow Joint: Includes Carbal bones, Metacarbal, and phalanges. Formed by Articulation of: humorous and Ulna (Ulno-humeral joint). Humorous and Radius (Radio-capitellar joint) 2- Shoulder Girdle Bones: - Clavicle - Scapula - Proximal Humerus Joints: - Glenohumeral (GH) - Acromioclavicular (AC) - Sternoclavicular (SC) 1- Shoulder Joints: Glenohumeral Joint : - Articulation between the head of the humerus and the glenoid cavity of the scapula. - Provides a wide range of motion but is prone to dislocations. Acromioclavicular (AC) Joint: - Between the acromion of the scapula and the clavicle. Sternoclavicular (SC) Joint: - Between the clavicle and the sternum. 1-a- Shoulder Joint (Glenohumeral) A- Structure: (Synovial - Ball and Socket Joint)  Articulation: Between head of humorous (Ball) and Glenoid fossa of the scapula (Socket)  Labrum It is fibrocartilage cause deepening of the glenoid fossa, increasing joint stability. Shoulder Joint: (Cont’d) B- Stability: 1- Bony 2- Labrum 3- ligaments 4- Joint Capsule 5- Muscles 3- Ligaments of shoulder joint Coracoclavicular lig Acromioclavicular lig Glenohumeral Ligaments (GHL) Superior GHL Middle GHL Inferior GHL Coracoacromial Ligament Coracohumeral ligament Coracoclavicular ligament Acromioclavicular Ligament 4- Muscles of the Shoulder 1- Deltoid 4- Latissimus Dorsi 2- Rotator Cuff (SITS) 5- Biceps Brachii Supraspinatus Infraspinatus 6- triceps Brachii Teres Minor Subscapularis 3- Pectoralis Major Muscles of the Shoulder (Cont’d) 1- Deltoid: Function: Anterior fibers: Flexion and internal rotation. Middle fibers: Abduction of the arm. Posterior fibers: Extension and external rotation. Nerve supply: Axillary n. Muscles of the Shoulder (Cont’d) 2- Rotator Cuff (SITS) a) Supraspinatus Function: Abduction of shoulder b) Infraspinatus Function: Extension of shoulder c) Teres Minor Function: External rotation and extension of shoulder d) Subscapularis Function: internal rotation of shoulder  Supraspinatus Infraspinatus Teres Minor Nerve Supply: Supraspinatus  Suprascapular n. Subscapularis Infraspinatus  Suprascapular n. Teres Minor  Axillary n. Subscapularis  subscapular n. Muscles of the Shoulder (Cont’d) 3- Pectoralis Major: Function: Flexion, adduction, and internal rotation of the arm. Nerve supply: medial and lateral pectoral n Muscles of the Shoulder (Cont’d) 4- Latissimus Dorsi: Function: Extension, adduction, and internal rotation of the shoulder. (Climbing and swimming) Nerve supply: nerve to latissimus dorsi (Thoraco-dorsal n.) Muscles of the Shoulder (Cont’d) 5- Biceps Brachii: (long & short head) Function: Flexion, of the shoulder and elbow. Nerve supply: Musculocutaneous n. Muscles of the Shoulder (Cont’d) 6- Triceps Brachii: (Long , Lateral & Medial Head) Function: Extension of the shoulder and elbow. Nerve supply: Radial n.  5- Movements of shoulder joints Flexion: Anterior deltoid, pectoralis major, biceps brachii. Extension: Posterior deltoid, latissimus dorsi, triceps brachii. Abduction: Middle deltoid, supraspinatus. Adduction: Pectoralis major, latissimus dorsi, teres major. Internal Rotation: Subscapularis, pectoralis major, latissimus dorsi, anterior deltoid. External Rotation:Infraspinatus, teres minor, posterior deltoid. Circumduction:  combination of previous movements 2- Elbow Joint: Elbow Joint: (Cont’d) A- Structure: (Hing - synovial Joint)  Articulation: Humerous (Distal end) Ulna (Proximal end) Radius (Proximal end)  Elbow Joint: (Cont’d) B- Joints of the Elbow 1. Humeroulnar Joint: (Hing - Joint) Site: between distal end of humerus and proximal end of the ulna. Movements: flexion and extension 2. Humero-radial (Radio-capitellar) Joint: Site: between distal end of humerous and proximal end of radius Movement: Flexion and extension + supination and pronation 3. Proximal Radio-ulnar Joint: (Pivot - Joint) Site: between proximal end of radius and ulna Movement: supination and pronation Elbow Joint: (Cont’d) C- Stability: 1. Bony 2. Muscle 3. Capsule 4. Ligaments:  Medial collateral ligament (MCL)  Lateral Collateral Ligament (LCL)  Annular ligament D- Muscles of the Elbow 1- Biceps Brachii (Musculocutaneous n.) 2- Brachialis (Musculocutaneous n.) 3- Brachioradialis (Radial n.) Muscles of the Elbow (Cont’d) 1- Triceps Brachii (Radial n.) 2- Anconeus (Radial n.) Muscles of the Elbow (Cont’d) 1- Biceps Brachii (Musculocutaneous n.) 2- Supinator (Radial n.) Muscles of the Elbow (Cont’d) 1- Pronator Teres (Median n.) 2- Pronator Quadaratus (Median n.) E- Movements of the Elbow 1- Flexion:  Biceps brachii, brachialis, brachioradialis. 2- Extension:  Triceps brachii, anconeus. 3- Supination:  Biceps brachii, supinator. 4- Pronation:  Pronator teres, pronator quadratus.  MUSCULOSKELETAL ANATOMY AND PHYSIOLOGY For Cast Technician Program Students Dr Amr Waked Proximal Row: Scaphoid  ‫سام‬ ‫ي‬ Lunate  ‫الم‬ Proximal Triquetrum  ‫تهان‬ ‫ي‬ Pisiform  ‫بعنف‬ Distal Distal Row: Trapezium  ‫ضب‬ Trapezoid  ‫ضاري‬ Capitate  ‫كريم‬ Hamate  ‫هناء‬ A- Structure: (Condyloid - synovial Joint)  Articulation: 1. Distal Radio-Ulnar joint (DRUJ) Radius (Distal end) + Ulna (Distal end) 2. Radio-Carpal Joint  Radius (Distal end) + Carpal bones (Proximal row) 3. Mid-Carpal Joint  Proximal + Distal row of carpal bone 4. Inter- Carpal joint  between each individual carpal bone  Mid-Carpal Joint Radio-Carpal Joint Distal Radio-Ulnar joint (DRUJ) B- Stability: 1. Bony 2. Muscle 3. Capsule 4. Ligaments:  Ulnar collateral ligament (UCL) = MCL  Radial Collateral Ligament (RCL) = LCL  Palmar and Dorsal Radiocarpal ligament  Inter carpal ligament C- Muscles around wrist Flexor Carpi Radialis. All muscles supplied by  Median n. Except Flexor carpi ulnaris and medial ½ of flexor digitorum Flexor Carpi Ulnaris. profundus supplied by  ulnar n. Palmaris Longus (may be absent). Flexor Digitorum Superficialis. Flexor Digitorum Profundus. Flexor Carpi Radialis: Flexion and abduction of the wrist. Flexor Carpi Ulnaris: Flexion and Adduction of the wrist. Flexor Digitorum Superficialis: Flexion of the fingers and help in wrist flexion. Flexor Digitorum Profundus: Flexion of the fingers and help in wrist flexion.  All muscles supplied by  Radial n. Extensor Carpi Radialis (Longus & Brevis). Extensor Carpi Ulnaris. Extensor Digitorum. Extensor Digiti minimi. Extensor Carpi Radialis: (longus & Brevis) Extension and abduction of the wrist. Extensor Carpi Ulnaris: Extension and Adduction of the wrist. Extensor Digitorum : Extension of the fingers and help in wrist extension. Extensor Digiti Minimi : Extension of the little finger and help in wrist extension. D- Movement of the wrist Flexion: flexor carpi radialis, flexor carpi ulnaris. Extension: extensor carpi radialis, extensor carpi ulnaris. Abduction: flexor carpi radialis, extensor carpi radialis. Adduction: flexor carpi ulnaris, extensor carpi ulnaris. Circumduction: combination of flexion, extension, abduction, and adduction. E- Tendon around the wrist Flexor Tendons: Pass through the carpal tunnel, secured by the flexor retinaculum on palmer aspect of the wrist. Extensor Tendons: Secured by the extensor retinaculum on the dorsal aspect of the wrist. Intrinsic Muscles Extrinsic Muscles Located within the hand. Located in the forearm and control the hand by tendons. 1. Thenar Muscles (Thumb): a) Adductor Pollicis. b) Abductor Pollicis Brevis. c) Flexor Pollicis Brevis. d) Opponens Pollicis. 2. Hypothenar Muscles (Little Finger): a) Abductor Digiti Minimi. b) Flexor Digiti Minimi Brevis. c) Opponens Digiti Minimi. 3. Lumbricals 4. Interossei Muscles: a) Palmar Interossei. b) Dorsal Interossei.  Adductor pollicis Thenar Muscles (Thumb): 1. Adductor pollicis  adduction of the thumb 2. Abductor Pollicis Brevis abduction of the thumb 3. Flexor Pollicis Brevis flexion of the thumb 4. Opponens Pollicis.  opposition of thumb All supplied by Median n. except Adductor pollicis supplied by ulnar n. Hypothenar Muscles (Little Finger): a) Abductor Digiti Minimi. abduction of little finger b) Flexor Digiti Minimi Brevis  flextion of little finger c) Opponens Digiti Minimi  opposition of little finger All supplied by Ulnar n. Lumbricals: Flex the metacarpophalangeal (MCP) joints and extend the interphalangeal (IP) joints. Nerve supply: Lateral 2 supplied by Median n. and medial 2 supplied by ulnar n. Interossei Muscles: a) Palmar Interossei  adduction of fingers. b) Dorsal Interossei abduction of fingers All interossei supplied by Ulnar n. 1. Flexor Group: (all supplied by Median except flexor digitorum profundus) a) Flexor pollicis longus ** b) Flexor Digitorum Superficialis. c) Flexor Digitorum Profundus. 2. Extensor Group:(all supplied by Radial n.) a) Extensor Digitorum. b) Extensor Pollicis Longus & Brevis. ** 3. Abductor Group:(supplied by Radial n.) a) Abductor Pollicis Longus. ** Flexor Pollicis longus: Flexion of the thumb. Nerve supply: Median n. Extensor Pollicis longus and Brevis: extension of the thumb. Nerve supply: radial n. Abductor Pollicis longus: Abduction of the thumb. Nerve supply: radial n. Blood supply of upper limb