Anatomy Revision – Some Important Question Related to Anatomy

1. In Anatomy Revision, Explain the bones and bony structure of the skull,  and the cranial fossae, and their opening in detail?

In Anatomy Revision, the cranium can be subdivided into a roof (known as the calvarium), and a base: Calvarium: Comprised of the frontal, occipital, and two parietal bones.

CRANIAL FOSSAE:

The anterior cranial fossa : Important Landmarks 
  The frontal crest. ·        The crista galli (latin for cock’s comb) ·        Nerves and other aspects:  Anterior ethmoidal foramen – transmits the anterior ethmoidal artery, nerve and vein. Posterior ethmoidal foramen – transmits the posterior ethmoidal artery, nerve and vein.

 

·        The frontal crest.
·        The crista galli (latin for cock’s comb)
·        Nerves and other aspects: 

Anterior ethmoidal foramen – transmits the anterior ethmoidal artery, nerve and vein.

Posterior ethmoidal foramen – transmits the posterior ethmoidal artery, nerve and vein.

 

The middle cranial fossa: Landmarks: 

The middle cranial fossa: Landmarks: 

 

·        CENTRAL: – The tuberculum sellae,The hypophysial fossa or pituitary fossa , The dorsum sellae.

·        LATERAL: – The depressed lateral parts the greater wings of the sphenoid bone, and the squamous and petrous parts of the temporal bones.

·   Sphenoid Foraminas: The superior orbital fissure:  transmits the oculomotor nerve (CN III), trochlear nerve (CN IV), ophthalmic branch of the trigeminal nerve (CN V1), abducens nerve (CN VI), opthalmic veins and sympathetic fibres.

·        The foramen rotundum: transmits the maxillary branch of the trigeminal nerve (CN V2).

·        The foramen ovale: transmitting the mandibular branch of the trigeminal nerve (CN V3) and accessory meningeal artery.

·        The foramen spinosum: It transmits the middle meningeal artery, middle meningeal vein and a meningeal branch of CN V3.

·        Foramina of temporal bones:

        1. Hiatus of the greater petrosal nerve  – transmits the greater petrosal nerve (a branch of the facial nerve), and the petrosal branch of the middle meningeal artery.
        2. Hiatus of the lesser petrosal nerve – transmits the lesser petrosal nerve (a branch of the glossopharyngeal nerve).
        3. Carotid canal – located posteriorly and medially to the foramen ovale. This is traversed by the internal carotid artery, which ascends into the cranium to supply the brain with blood. The deep petrosal nerve also passes through this canal.

The posterior cranial fossa 

The posterior cranial fossa 

 

·        The posterior cranial fossa is comprised of three bones: the occipital bone and the two temporal bones.

·        The floor consists of the mastoid part of the temporal bone and the squamous, condylar and basilar parts of the occipital bone

·        The posterior cranial fossa houses the brainstem and cerebellum.

FORAMINAS: 

FORAMINAS

 

 

1. Temporal Bone: The internal acoustic meatus is an oval opening in the posterior aspect of the petrous part of the temporal bone. It transmits the facial nerve (CN VII), vestibulocochlear nerve (CN VIII), and labyrinthine artery.

2. Occipital Bone: The foramen magnum, lies centrally in the floor of the posterior cranial fossa. It is the largest foramen in the skull. It transmits the medulla of the brain, meninges, vertebral arteries, spinal accessory nerve (ascending), dural veins, and anterior and posterior spinal arteries. Anteriorly an incline, known as the clivus, connects the foramen magnum with the dorsum sellae.

3. The jugular foramina are situated on either side of the foramen magnum. Each transmits the glossopharyngeal nerve, vagus nerve, spinal accessory nerve (descending), internal jugular vein, inferior petrosal sinus, sigmoid sinus, and meningeal branches of the ascending pharyngeal and occipital arteries.

4. The anterolateral margin of the foramen magnum is the hypoglossal canal. It transmits the hypoglossal nerve through the occipital bone.

5. Postero-laterally to the foramen magnum lies the cerebellar fossae. These are bilateral depressions that house the cerebellum. They are divided medially by a ridge of bone, the internal occipital crest.


2. In Anatomy Revision, Explain vertebral column and regional division of its bony components and curvature?

2. In Anatomy Revision, Explain vertebral column and regional division of its bony components and curvature?
 

The vertebral column is a curved structure composed of bony vertebrae that are interconnected by cartilaginous intervertebral discs. It consists of 33 vertebrae.
Key facts about the vertebral column

·        Regions

·        Cervical, thoracic, lumbar, sacral, coccygeal

·        Typical vertebra

·        Vertebral body, vertebral arch (pedicles, lamina), vertebral processes (spinous, transverse, articular)

·        Joints

·        Intervertebral discs, uncovertebral, zygapophysial (facet), craniovertebral (atlantooccipital, atlanto-axial), costovertebral, sacroiliac

·        Ligaments

·        Longitudinal (anterior, posterior), ligamenta flava, interspinous, supraspinous, nuchal, alar, cruciate ligament of the atlas, costotransverse, ligaments of the head of the rib (intra-articular, radiate)

·        Curvatures

·        cervical lordosis, thoracic kyphosis, lumbar lordosis, sacral kyphosis

·        Movements

·        Flexion, extension, lateral flexion, lateral extension, rotation

·        Vasculature

·        Segmental arteries and vertebral venous plexus (internal, external)

·        Nerves

·        Meningeal branches of spinal nerves


3. In Anatomy Revision, Give detail about the synovial joint and its type? 

3. In Anatomy Revision,, Give   detail about  synovial joint and its type? 
 

·        A synovial joint is a connection between two bones consisting of a cartilage lined cavity filled with fluid, which is known as a diarthrosis joint.

·         Diarthrosis joints are the most flexible type of joint between bones because the bones are not physically connected and can move more freely about each other. 

·        STRUCTURE: consists of A synovial membrane, Synovial fluid, synovial bursa

·        Synovial joints are further classified into six different

  1. ·        Planar:
  2. ·        Hinge
  3. ·        Pivot.
  4. ·        Condyloid.
  5. ·        Saddle:
  6. ·        Ball-and-socket joints: Ball-and-socket joints possess a rounded, ball-like end of one bone fitting into a cuplike socket of another bone.

4. In Anatomy Revision, What are the types of bones, and explain how long bone looks like?

4. In Anatomy Revision,What are the types of bones and explain how long bone looks like?
 

1.     Long bones: These bones typically have an elongated shaft and two expanded ends one on either side of the shaft. The shaft is known as diaphysis and the ends are called epiphyses. Normally the epiphyses are smooth and articular. The shaft has a central medullary cavity where lies the bone marrow.  

 

     Typical long bones: They have an elongated shaft and two ends and are represented by bones such as humerus, femur, radius, ulna, tibia, and fibula. 

 

     Miniature long bones: As the name indicates, these bones have a miniature appearance and often they have only one epiphysis. Examples of this class of long bones are metacarpals, metatarsals, and phalanges of both upper and lower limbs. 

 

      Modified long bones: These bones either have modified shafts or ends. They have no medullary cavity which is present in the typical long bones. Examples of this class of bones are the clavicle and body of vertebrae.

 

2.      Short bones: These bones are short in posture and can be of any shape. Most of them are named according to their shape. Examples of this class of bones include cuboid, cuneiform, scaphoid, trapezoid, etc. In fact, all the carpal and tarsal bones are included in this category.

 

3.     Flat bones,

4.     Irregular bones,

5.     Pneumatic bones,

6.     Sesamoid bones

 

Types based on development:

1.     Membranous bones,

2.     Cartilaginous bones,

3.     Membro-cartilaginous bones

 

Types based on region:

1.     Appendicular

2.     Axial

 

According to the Macroscopic approach;

1.     Compact bone,

2.     spongy bone

 

According to the Microscopic approach:

1.     Fibrous bone,

2.     Lamellar bone


5. In Anatomy Revision, Explain the joint that consists of the egg-shaped end of the metacarpal nestled in the depression of the neighboring phalange bone.

Explain the joint that consists of the egg shaped end of the metacarpal nestled in the depression of the neighboring phalange bone.
 
Condyloid joint:

At a condyloid joint (ellipsoid joint), the shallow depression at the end of one bone articulates with a rounded structure from an adjacent bone or bones 

·        The knuckle (metacarpophalangeal) joints of the hand between the distal end of a metacarpal bone and the proximal phalanx bone are condyloid joints.

·        example is the radiocarpal joint of the wrist, between the shallow depression at the distal end of the radius bone and the rounded scaphoid, lunate, and triquetrum carpal bones.

·        In this case, the articulation area has a more oval (elliptical) shape.

·        Functionally, condyloid joints are biaxial joints that allow for two planes of movement. 

·        One movement involves the bending and straightening of the fingers or the anterior-posterior movements of the hand.

·        The second movement is a side-to-side movement, which allows you to spread your fingers apart and bring them together, or to move your hand in a medial-going or lateral-going direction.


6. In Anatomy Revision, Describe the knee joint and give detail of its menisci?

Hinge Joint: – hinge type synovial joint, which mainly allows for flexion and extension. It is formed by articulations between the patella, femur, and tibia. It consists of two articulations – tibiofemoral and patellofemoral. The joint surfaces are lined with hyaline cartilage and are enclosed within a single joint cavity. Tibiofemoral – medial and lateral condyles of the femur articulates with the tibial condyles. It is the weight-bearing component of the knee joint. The patellofemoral – anterior aspect of the distal femur articulates with the patella. It allows the tendon of the quadriceps femoris (knee extensor) to be inserted directly over the knee – increasing the efficiency of the muscle.

The medial and lateral menisci are fibrocartilage structures in the knee that serve two functions:

  1. To deepen the articular surface of the tibia, thus increasing the stability of the joint.
  2. To act as shock absorbers by increasing surface area to further dissipate forces.

Menisci: They are C shaped, and attached at both ends to the intercondylar area of the tibia.
In addition to the intercondylar attachment, the medial meniscus is fixed to the tibial collateral ligament and the joint capsule. Damage to the tibial collateral ligament usually results in a medial meniscal tear. The lateral meniscus is smaller and does not have any extra attachments, rendering it fairly mobile.


7. In Anatomy Revision, The joints of the hips and shoulders are an example of which type of joint? Explain?

Hip:  ball-and-socket synovial joint. The hip joint is the articulation of the pelvis with the femur, which connects the axial skeleton with the lower extremity. The ligaments of the hip joint act to increase stability. They can be divided into two groups – intracapsular and extracapsular.
The arterial supply to the hip joint is large via the medial and lateral circumflex femoral arteries. The medial circumflex femoral artery is responsible for the majority of the arterial supply. The hip joint is innervated primarily by the sciatic, femoral, and obturator nerves.
Shoulder: synovial ball and socket joint. The shoulder joint is formed by the articulation of the head of the humerus with the glenoid cavity of the scapula. The glenohumeral joint is a muscle-dependent joint as it lacks strong ligaments. The primary stabilizers of the shoulder include the biceps brachii on the anterior side of the arm and tendons of the rotator cuff Ligaments :

  1. Capsular ligaments – Superior, middle, and inferior glenohumeral ligaments
  2. Coracohumeral ligament
  3. Transverse humeral ligament
  4. Coraco-acromial ligament.

Innervation; The nerves supplying the shoulder joint all arise in the brachial plexus. They are the suprascapular nerve, the axillary nerve, and the lateral pectoral nerve.
Blood supply The shoulder joint is supplied with blood by branches of the anterior and posterior circumflex humeral arteries, the suprascapular artery, and the scapular circumflex artery.


8. In Anatomy Revision, Describe joints and how joints classified by both structure and function?

Joints are the areas where 2 or more bones meet. Most joints are mobile, allowing the bones to move.  The structural classification divides joints into fibrous, cartilaginous, and synovial joints. The functional classification divides joints into three categories: synarthroses, amphiarthroses, and diarthrosis.
A fibrous joint is where the bones are bound by a tough, fibrous tissue.
In a cartilaginous joint, the bones are united by fibrocartilage or hyaline cartilage.
A synovial joint is defined by the presence of a fluid-filled joint cavity contained within a fibrous capsule.
Hinge permits movement in one plane – usually flexion and extension. E.g. elbow joint, ankle joint, knee joint.
Saddle . It is characterized by opposing articular surfaces with a reciprocal concave-convex shape. E.g. carpometacarpal joints.
Pivot – allows for rotation only. It is formed by a central bony pivot, which is surrounded by a bony-ligamentous ring E.g. proximal and distal radioulnar joints, atlantoaxial joint.
Condyloid – contains a convex surface that articulates with a concave elliptical cavity. They are also known as ellipsoid joints. E.g. wrist joint, meta Carpo phalangeal joint, meta tarso phalangeal joint.
Ball and Socket – where the ball-shaped surface of one rounded bone fits into the cup-like depression of another bone. It permits free movement in numerous axes. E.g. hip joint, shoulder joint.


9. In Anatomy Revision, Explain the only movable bone in the human skull?

9. In Anatomy Revision,Explain the only movable bone in human skull ?
 

The mandible, located inferiorly in the facial skeleton, is the largest and strongest bone of the face. It forms the lower jaw and acts as a receptacle for the lower teeth. It also articulates on either side with the temporal bone, forming the temporomandibular joint.
Anatomical Structure: – The mandible consists of a horizontal body (anteriorly) and two vertical rami (posteriorly). The body and the rami meet on each side at the angle of the mandible. The body; Mandible’s body is curved and shaped much like a horseshoe. It has two borders:*Alveolar border *Base. The body is marked in the midline by the mandibular symphysis. The internal surface of the ramus is also marked by the mandibular foramen, which acts as a passageway for neurovascular structures.
Muscle attachments; Mandibular body: External (lateral) surface – mentalis, buccinator, platysma, depressor labii inferioris, depressor anguli oris.Internal (medial) surface – genioglossus, geniohyoid, mylohyoid, and digastric.Mandibular rami – masseter, temporalis, medial pterygoid, and lateral pterygoid.


10. In Anatomy Revision, Explain bone in the body that has the following features and characteristics: Linea  Aspera, the intercondylar notch, and an anterior bow to its shaft? Give an account of detail about the joint located there? Explain hamstring muscles and where it is located? Give details about its type?

10. In Anatomy Revision,Explain  bone in the body which has the following features and characteristics: linea  aspera, intercondylar notch and an anterior bow to its shaft? Give account of  detail about joint located their? Explain hamstring muscles and where it is located ? Give details about its type?

Linea Aspera, shaft, notch: – This bone is the femur, Longest bone, the Thighbone, forms a ball-and-socket joint with the hip (at the acetabulum), held in place by a ligament (ligamentum teres femoris) within the socket. the neck of the femur connects the shaft and head at a 125° angle, which is efficient for walking.

The femur at the outside top of the thigh provides attachment for the gluteus medius and minimus muscles. The shaft is convex forward and strengthened behind by a pillar of bone called the lineaaspera.

Two large condyles, on either side of the lower end of the femur, form the upper half of the knee joint, which is completed below by the tibia (shin) and patella (kneecap). Internally, the femur shows the development of arcs of bone called trabeculae that are efficiently arranged to transmit pressure and resist stress.

It consists of two bony processes – the greater and lesser trochanters. There are also two bony ridges connecting the two trochanters; the intertrochanteric line, trochanteric crest posteriorly.

Head – It has a smooth surface, covered with articular cartilage and a fovea.

Neck – connects the head of the femur with the shaft, cylindrical.

Greater trochanter – The most lateral palpable projection of bone that originates from the anterior aspect, just lateral to the neck.

Lesser trochanter – smaller than the greater trochanter. It is the site of attachment for iliopsoas.

Intertrochanteric line – a ridge of bone that runs in an infero-medial direction on the anterior surface of the femur.

Intertrochanteric crest 

Like the intertrochanteric line, this is a ridge of bone that connects the two trochanters, Posterior surface of the femur, The shaft of the femur descends in a slight medial distal, increasing stability, A cross-section of the shaft in the middle is circular.

the posterior surface of the femoral shaft, there are roughened ridges of bone, called the lineaaspera. These split inferiorly to form the medial and lateral supracondylar lines. Proximally the medial border of the lineaaspera becomes the pectineal line. 

The lateral border becomes the gluteal tuberosity, Distally, the lineaaspera widens and forms the floor of the popliteal fossa, the medial and lateral borders form the medial and lateral supracondylar lines.

Medial and lateral condyles – rounded areas at the end of the femur,

The posterior and inferior surfaces articulate with the tibia and menisci of the knee, while the anterior surface articulates with the patella. The more prominent lateral condyle helps prevent the natural lateral movement of the patella; a flatter condyle is more likely to result in patellar dislocation.

Medial and lateral epicondyles – bony elevations on the non-articular areas of the condyles. medial epicondyle larger.

Intercondylar fossa – a deep notch on the posterior surface of the femur, between the two condyles.


11. In Anatomy Revision, Describe the movements of the ankle joint and explain muscles allowing them?

11. In Anatomy Revision,Describe the movements of the ankle joint and explain muscles allowing them?
 
Plantarflexion

The anterior part of the talus is held in the mortise, and the joint is less stable. Produced by the muscle of the posterior compartment of the leg. The posterior compartment of the leg contains seven muscles, organized into two layers – superficial and deepSuperficial muscles are Gastrocnemius, soleus, and plantaris.

1)Gastrocnemius:Attachments:  originates from the lateral femoral condyle, and the medial head from the medial femoral condyle combines with the soleus to form the calcaneal tendon. Actions: It plantarflexes ankle joint.

2)Plantaris: Attachments: Originates from the lateral supracondylar line of the femur. The muscle descends medially. Actions: It plantarflexes at the ankle joint, it is flexor.

3)Soleus:-. Attachments: Originates from the so leal line of the tibia and joins the calcaneal tendon.Actions: Plantarflexes the foot. Deep muscles are popliteus, Tibialis posterior, Flexor Digitorum longus

1)Popliteus:-Attachments: Originates from the lateral condyle of the femur and the posterior horn of the lateral meniscus.Actions: Laterally rotates the femur on the tibia – flexor.

2)Tibialis posterior:-Attachments: Originates from the interosseous membrane between the tibia and fibula, and posterior surfaces of the two bones. Actions: Inverts and plantarflexes the foot.

3)Flexor Digitorum Longus:-Attachments: Originates from the medial surface of the tibia, attaches to the plantar surfaces of the lateral four digits.Actions: Flexes the lateral four toes.part part of the talus is held in the mortise, and the joint is less stable. Produced by the muscle of the anterior compartment of the leg. Nerve innervation for all muscles is tubular nerve.

Dorsiflexion

more stable. Produced by an anterior compartment of the leg. four muscles in the anterior compartment of the leg; tibialis anterior, extensor digitorum longus, extensor hallucis longus, and fibularis tertius.

1) Tibialis Anterior:- Attachments: Originates from the lateral surface of the tibia, attaches to the medial cuneiform and the base of metatarsal IActions: Dorsiflexion and inversion of the foot.

2) Extensor digitorium longus:- Attachments: Originates from the lateral condyle of the tibia and the medial surface of the fibula. The fibers converge into a tendonActions: Extension and dorsiflexion of the toe.

3)extensor hallucis longus:- Attachments: Originates from the medial surface of the fibular shaft.Action: Extension of the great toe, dorsiflexion of the foot. Nerve innervation for all muscles is deep fibular nerve


12. In Anatomy Revision, What are the three types of muscle fibers found in the skeletal muscles. explain?  Identify two structural and two functional differences in their characteristics?

12. In Anatomy Revision,What are the three types of the muscles fibers found in the skeletal muscles. explain?  Identify two  structural and two functional difference in their characteristics?
Skeletal Muscles
3 types of muscle fibre in skeletal muscles: –
1)    red/slow(type1 muscle fibre)
2)    red/fast (type2a muscled)
3)    White/fast (type2b muscle f).

1) type1:- twitch fibers (Type I):  Slow twitch fibers contract slowly but can contract repeatedly over long periods.  They have a good blood supply, hence they are ‘red fibers’, and are suited to endurance activity using the aerobic energy system which relies on oxygen from the blood for the supply of energy. Slow-twitch fibers are smaller and develop less force than fast-twitch fibers.

2) Type2a.:-Fast-twitch IIa fibers have a fast contraction speed and can use aerobic (oxygen dependant) energy sources as well as anaerobic (no oxygen used) energy sources.  Fast-twitch IIa fibers are ‘white fibers’ as they are less reliant on oxygen supplied by the blood for energy and therefore fatigue faster than slow-twitch fibers. These fibers are also suited to speed, strength, and power type activities, such as moderately heavy weight training.

3) Type2b:twitch IIb fibers contract extremely rapidly, create very forceful muscle contractions, and fatigue quickly.  Fast-twitch IIb fibers are also ‘white fibers’ but unlike IIa fibers they can only use anaerobic energy sources. Like type IIa fibers the fast-twitch type IIb fibers are also suited to speed, strength, and power type activity.  


13. In Anatomy Revision, Describe the shoulder joint under the following headings: Articular surfaces, ligaments, relations, muscles and movement, and applied anatomy.

13. In Anatomy Revision,Describe the shoulder joint under the following headings: Articular surfaces, ligaments, relations, muscles and movement and applied anatomy.

Shoulder joint: –

Articular surface: – head of the humerus with a glenoid cavity. glenohumeral joint. The articulating surfaces are covered with hyaline cartilage. head of the humerus is larger than the glenoid fossa, giving the joint a wide range of movement at the cost of inherent instability. To reduce the disproportion in surfaces, the glenoid fossa is deepened by a fibrocartilage rim, called the glenoid labrum.

Ligaments: – for stabilizing the bony structure.

1) Glenohumeral L.:- to stabilize the anterior aspect of the joint.

2) Coracohumeral L:-attaches the base of the coracoid process to the greater tubercle of the humerus.

3)Transverse humeral L:-holds the tendon of the long head of the biceps in the intertubercular groove.

4)Caraco Clavicular Ligament:- composed of the trapezoid and conoid ligaments and runs from the clavicle to the coracoid process of the

 

movements:-

1) Extension (upper limb backward in the sagittal plane).

2) Flexion (upper limb forwards in the sagittal plane) – pectoralis major, anterior deltoid, and coracobrachialis.

3) Abduction (upper limb away from the midline in the coronal plane).

4) Adduction (upper limb towards the midline in the coronal plane) – pectoralis major, latissimus dorsi, and teres major.

5) Internal rotation (rotation towards the midline, so that the thumb is pointing medially).

6).External rotation (rotation away from the midline, so that the thumb is pointing laterally). 


14. In Anatomy Revision, Shoulder, Elbow, Hip, Knee, and Ankle joints are all synovial joints: 1)Explain the bone that articulates at each of these joints 2)Explain the type of synovial joint located at each of these joints.

1) Elbow joint: – The elbow joint is a complex hinge joint formed between the distal end of the humerus in the upper arm and the proximal ends of the ulna and radius in the forearm. The elbow allows for the flexion and extension of the forearm relative to the upper arm, as well as rotation of the forearm and wrist.
2) Ankle jointThe Ankle Joint, also known as the Talocrural Articulation, is a synovial hinge joint connecting the distal ends of the tibia and fibula in the lower limb with the proximal end of the talus.


15. In Anatomy Revision, Write in brief about the muscles arises from the third, fourth, and fifth ribs and are inserted into the coracoid process of the scapula?

Pectoralis Minor:
Origins: – Anterior surface of the 3rd, 4th, and 5th ribs and the fascia overlying the intercostal spaces
Insertions: – Medial border and coracoid process of the scapula
Innervation: – Medial pectoral nerve (C8-T1)
Function: – Scapulothoracic joint: Draws scapula anteroinferior, stabilizes scapula on the thoracic wall.


16. In Anatomy Revision, Explain three types of fibrous joints? Give detail about vertebro- costal joint?

fibrous joints:  simpler, less mobile. The articulating edges of bones attached to fibrous connective tissue. Motion at these joints is negligible. Fibrous joints are found in the body’s three areas.
In the skull, by three years of age, all the fontanelle (soft regions between cranial bones) would have fused. The remnants, referred to as cranial sutures, are fibrous connections (sutural ligaments) that occupy the joint space. The adjacent bones will completely ossify with time, which may result in obliteration of the suture lines.
The second example of fibrous joints is those of the distal tibiofibular and the cuboid-navicular (cuboid and navicular bones) joints. By interosseous ligaments, they are held in place which is also known as syndesmosis joints.
The final fibrous joint is found in the mouth, where the pegged end of the teeth articulates with the dental alveoli. This joint is referred to as a gomphosis joint.

Vertebro-coastal joint:

A synovial, gliding joint between a vertebra and rib which is strengthened by the ligament of the head and the inter-capital ligament. Articulated by a dorsal costotransverse ligament.
It consists of:

      The superior costal facet of the corresponding vertebra

      An inferior costal facet of the superior vertebra

      Intervertebral disc separating the two vertebrae

The costovertebral joint and costovertebral ligaments play a pivotal role in thoracic stabilization, load-bearing, mobility, protection, and chest wall movement, all while contributing heavily to respiratory effort.


17. In Anatomy Revision, Explain in detail the heaviest and longest bone of the human body?    

The femur bone is the strongest and longest bone in the body, occupying the space of the lower limb, between the hip and knee joints.

Landmarks: –
Proximal end – head, neck, greater trochanter, lesser trochanter, intertrochanteric crest
Shaft – Borders: lateral and medial; Surfaces: anterior, medial, lateral; Ridges: lateral ridge (gluteal tuberosity), pectineal line, spiral line (these three lines converge and form the linea Aspera)
Distal end – lateral and medial condyles, intercondylar fossa, lateral and medial epicondyles

Joints
Hip: femoral head with the acetabulum of the pelvis
Knee: lateral and medial condyles of the femur with the tibial plateaus of the tibia (tibiofemoral joint); Patellar surface of the femur with the posterior surface of the patella (patellofemoral joint)

Blood supply – Trochanteric anastomosis, cruciate anastomosis

Disorders of the femur – neck of femur fractures, slipped capital femoral epiphysis, femoro-acetabular impingement.


20. In Anatomy Revision, Explain four muscles forming ‘’the rotator muscle cuff ’’.  Give their attachments and mention their importance?

In the human body, the rotator cuff is a functional anatomical unit located in the upper extremity.
Its function is related to the glenohumeral joint, where the muscles of the cuff function both as the executors of the movements of the joint and the stabilization of the joint as well.
 Rotator cuff
Teres minor muscle (Musculus teres minor)
In the human body, the rotator cuff is a functional anatomical unit located in the upper extremity.
Its function is related to the glenohumeral joint, where the muscles of the cuff function both as the executors of the movements of the joint and the stabilization of the joint as well.
Injuries of the rotator cuff interfere with the function of the glenohumeral joint and correspond with an inability to perform the movements associated with this joint.

Key facts

Supraspinatus muscle

·        Origin: supra-spinatous fossa of scapula

·        Insertion: greater tubercle of the humerus

·        Innervation: suprascapular nerve (C4, C6)

·        Function: initiation of the abduction of arm to 15° at the glenohumeral joint; stabilization of humeral head in the glenoid cavity.

 

Infraspinatus muscle

·        Origin: infra-spinatous fossa of scapula

·        Insertion: greater tubercle of the humerus

·        Innervation: suprascapular nerve (C5, C6)

·        Function: external rotation of the arm at the glenohumeral joint; stabilization of the humeral head in the glenoid cavity.

 

Teres minor muscle

·        Origin: lateral border of the scapula

·        Insertion: greater tubercle of the humerus

·        Innervation: axillary nerve (C5, C6)

·        Function: external rotation and adduction of the arm at the glenohumeral joint; stabilization of the humeral head in the glenoid cavity.

 

Subscapularis muscle

·        Origin: medial two-third of the subscapular fossa

·        Insertion: lesser tubercle of the humerus

·        Innervation: upper and lower subscapular nerves (C5, C7)

·        Function: internal rotation of arm; stabilization of humeral head in the glenoid cavity.

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