Musculoskeletal/Upper Limb/Lower Limb Anatomy Flashcards
Describe the Trunk/Torso
The central region of the body.
Includes thorax, abdomen and pelvis
Doesn’t include neck,head or any of the upper or lower limbs
Describe the thorax?
The thorax is the upper part of the trunk/torso
This is from the bottom of the neck to the diaphragm.
The organs found within are the lungs and heart protected by the ribs.
Chest is the term to describe the front of the thorax
Describe the abdomen?
This is the central part of the trunk/torso
Between the diaphragm and the top of the pelvic bone
Holds most of the digestive Tract such as the stomach, intestines both small and large and liver.
Describe the pelvis?
This is the lowest part of the trunk/torso
From the lower abdomen to the start of the lower limbs
Contains the last of the digestive tract, bladder and all reproductive organs.
The bony ring structure is also called the pelvis
Describe the back?
The back anatomically is used to refer to the whole posterior surface of the trunk/torso
Describe the arm?
The arm is an anatomical term used to describe the upper section of the upper limb, this is from the shoulder to the elbow.
This is where the bicep muscle can be found
Describe the forearm?
The forearm is an anatomical term used to describe the middle/lower portion of the upper limb from the elbow to the wrist
Describe the Thigh?
The thigh is the anatomical term for the upper portion of the lower limb from the pelvis to the knee
Describe the Leg?
The leg is an anatomical term for the middle/lower portion of the lower limb from the knee to the ankle
What is the anatomical position?
The anatomical position is when a person is standing up, feet flat on the floor, facing forward, arms by their sides with the palms facing forwards
Superior meaning with example
ABOVE
Eg- The brain is superior to the heart
Inferior
Meaning and example
BELOW
Eg- the pelvis is inferior to the thorax
Anterior
Meaning and example
Anterior also known as Ventral= Front/ in front of
Eg- the nose is anterior to the ears
Posterior
Meaning and example
Posterior also known as Dorsal= Back/Behind
Eg- The spine is posterior to the sternum
Medial
Meaning and example
Close to the midline
Eg- The big to is medial to the little toe
Lateral
Meaning and example
Further away from the midline
Eg- The thumb is lateral to the palm
Proximal
Meaning and example
Closer to the origin
Eg- the elbow is proximal to the wrist
Distal
Meaning and example
Further away from the origin
Eg- the toes are distal to the knee
Ipsilateral
Meaning and example
The same side of the body
Eg- the right arm and the right leg are ipsilateral to each other
Contralateral
Meaning and example
The opposite side of the body
Eg- The right arm and the left leg are contralateral to each other
Deep
Meaning and example
Further away from the surface
Eg- the heart is deep to the sternum
Superficial
Meaning and example
Closer to the surface
Eg- The skin is superficial to muscle
Supine (position)
Meaning and example
Lying down, flat on the back, facing up
Prone (position)
Meaning and example
Lying down, on front, face down
Cranial
Meaning and example
Towards the head
Eg- the brain is cranial to the spinal coard
Caudal
Meaning and example
Towards the tail
Eg- the pelvis is caudal to the abdomen
Rostral
Meaning and example
Towards the face
Eg- the frontal lobe is rostral to the occipital lobe
Coronal Plane
Also known as frontal
Face on- this plane cuts into anterior and posterior
Sagittal Plane
Side on- cuts into left and right
Parasagittal= cut in sagittal plane but parallel to the midline (off to one side or the other)
Axial plane
Also known as transverse or horizontal
End on- cuts into superior and inferior
Axial skeleton
Central/core parts
Eg- skull, vertebral column, ribs and sternum
Appendicular skeleton
The bones of the limbs
Includes- Scapular, clavicle and the pelvic girdle
What is the skeleton?
The skeleton is split into 2 sub-divisions, the axial and appendicular.
The skeleton is bony scaffolding, made up of bone and cartilage.
The bone is hard and rigid, whereas cartilage is more flexible.
When babies are bone most of their skeleton is made of cartilage which over time ossifies to bone. Some will remain as cartilage such as the anterior of the ribs
What is a joint
A joint is where two bones meet and articulate with each other
Eg- the femur and tibia, articulate at the knee joint
SYNOVIAL JOINTS
Most common type of joint
A narrow cavity separates both articulate surfaces of the bones. The cavity contains lubricating synovial fluid which is enclosed in a joint capsule. The joint capsule consists of 2 layers- an outer fibrous capsule and an inner synovial membrane.
Each surface which articulate are covered with a articular hyaline cartilage.
Synovial joints usually allow a great deal of movement
EG- shoulders, knee and wrist.
FIBROUS JOINTS
These joints connect via strong fibrous tissue. No cavity or fluid like with synovial joints.
These have very little movement
Eg- sutures between the individual bones in the skull
CARTILAGINOUS JOINTS
These joints are like fibrous joints, but instead are separated by cartilage instead of fibrous tissue.
There are 2 subtypes
- Primary cartilaginous joints which are connected by hyaline cartilage allowing some flexibility eg- where ribs meet sternum
- Secondary cartilaginous joints which are connected by fibrocartilage and a layer of hyaline cartilage. These type are flexible but strong so can support a lot of weight. Eg- intervertebral discs between vertebrae and the spine.
BALL AND SOCKET JOINT
The end of one bone is shaped as a ball and the other is the shape of a bowl. This means the ball fits inside the bowl, eg-shoulder joint.
These joints are mobile and can allow a significant range of movement in many directions including rotation.
The stability and mobility of these joints all depends on the fit of the socket.
The better fit the more stable the joint is but less mobile.
The poorer the fit the less stable the joint is bout with better mobility so from these have an increased risk of dislocation.
HINGE JOINT
This joint acts like the hinge on a door, the joint allows for a range of movement, but only in one plane eg-elbow or knee
PIVOT JOINT
This is the joint found at the top of the spine where the first and second vertebrae articulate. The first vertebrae at the base of the skull pivots around the peg of the second vertebrae which allows rotational movement allowing us to turn our head left and right.
SADDLE JOINT
These joints are shaped like a rider sat in a saddle. This joint permits movement in 2 planes.
Eg the joint at the base of the thumb where the metacarpal of the thumb articulates with one of the small carpal bones.
This is the carpometacarpal joint of the thumb
CONDYLOID JOINT
This joint is like a ball and socket joint but the two surfaces of the bone are oval-shaped. These have a good range of movement but only in 2 planes. Eg- the wrist joint and the metacarpophalangeal joint of the fingers or the knuckles
PLANE JOINT
This joint is where the articulating surfaces are almost flat which glide against each other. The movement from these is usually limited and is dictated by neighbouring bones and ligaments. Eg- joints between the small bones of the wrist and the acromioclavicular joint at the top of the shoulder.
What is a ligament?
A ligament is a band of connective fibrous tissue that attaches bones, to bones. They are used to stabilise joints and limit the movement.
Ligaments can stretch over time, which in turn over time can provide greater joint mobility.
The term double jointed actually means they have ligaments which are stretchy enough to allow more movement and is known as hyper mobility.
What is a sprain?
A sprain occurs when a ligament becomes overstretched and injured.
The most often sprained ligament are those within the ankle cause by one going over on the ankle causing forced excessive inversion. The over stretched and torn ligaments can be painful and as so may never return to their original shape.
What happens to a ligament when a joint dislocates?
When a joint dislocates the ligament will be stretched. It may become so over stretched that it will be permanently lax leading to joint instability and so regular or recurrent dislocation may occur.
Flexion
Bending
Decreasing the angle between 2 parts
Extension
Straightening
Increasing the angle between 2 parts
Lateral flexion
Bending sideways
Unique to the vertebral column
Abduction
Movement from midline
Adduction
Movement towards the midline
Internal Rotation
Rotating towards the midline
External rotation
Rotating away from the midline
Pronation
Unique to forearm
Internal rotation of the radius- means palms face posteriorly
Supination
Unique to the for forearm- external rotation of the radius so the palms face anteriorly eg-anatomical position
Opposition
Unique to thumb and little finger- flexion and rotation so that the thumb and little finger can reach each other
Circumduction
Combination of flexion, extension, abduction and adduction. Such that the appendage traces a circular or conical pattern
Dorsiflexion
Unique to the ankle- the foot and toes move superiorly towards the shin
Plantarflexion
Unique to the ankle- the foot and toes move inferiorly- pointing toes down
Inversion
Unique to the foot and ankle- medial flexion so that the sole of the foot faces medially
Eversion
Unique to the foot and ankle- lateral flexion so that the sole of the foot faces laterally
Protraction
Unique to the scapula and mandible- moving the scapula or mandible anteriorly- eg moving the upper limb out in front as is pushing open a door
Retraction
Unique to the scapula and mandible- moving the scapula or mandible posteriorly- eg squaring the shoulders
Elevation
Unique to the scapula and mandible- moving the scapula or mandible superiorly eg- shrugging the shoulders or closing the mouth
Depression
Unique to the scapula and mandible- Moving the scapula or mandible inferiorly eg- returning the shoulders after elevation, opening the mouth
Skeletal muscle
Found throughout the body
Provide support, aid movement for joints and soft tissues eg- eyeball
They are under voluntary control which means we can consciously control them
They are striated in appearance
Smooth muscle
Muscle which is located in walls of the bloody vessels and internal organs eg- intestines
This muscle is involuntary and is controlled via the autonomic nervous system
We are unable to control
Not striated in appearance
Cardiac muscle
Muscle which is unique to the heart
They are involuntary controlled.
The muscle cells contact in response to the electrical impulses which are spontaneously generated by specialised cells within the heart.
The autonomic nervous system influences the cells and can either speed up or slow down the heart rate.
They are striated in appearance
Tendons
Tendons are composed of strong connective tissue which allows skeletal muscle to be attached to bone/soft tissue. The tendons are of a rounded shape like a cord but some form thin flat sheets known as aponeuroses such as in the scalp and abdominal wall.
The muscle between the tendons is off ten referred to as the muscle belly
How does skeletal muscle move
For them to move joints, muscles or tendons must cross them. When a muscle contracts on of its attachments must move while its second attachment does not. The bone or part that doesn’t move is called the origin and the attachment that does move is called the insertion.
PARALLEL Skeletal muscle
The fibres within this type of skeletal muscle are aligned parallel to each other. They can shorten significantly and quickly but are less powerful than pennate muscles. There are 2 sub-types of parallel skeletal muscle
- Fusiform= these muscles often have a long tendon at each end along with the muscle belly bulging out in the middle eg- biceps brachii
- Strap= these muscles are belt shaped and relatively uniform in width at the belly eg-sartorius in the thigh
CONVERGENT Skeletal muscle
These muscles are fan shaped which very broad attachments at one end. Fibres converging onto much smaller attachment at the other end. Eg- pectoralis major on the anterior chest wall
CIRCULAR Skeletal muscle
Within this muscle the fibres are arranged in concentric rings around a structure and often are called sphincters. When they contract they close the aperture they surround. Eg- muscles around lips and eyes
PENNATE Skeletal muscle
The fibres are arranged at an angle to the direction in which the muscle acts. They cannot shorten as much as parallel but they are powerful, there are 3 subtypes
- Unipennate= the fibres arranged diagonally in relation to the tendon and insert onto one side of the tendon only eg- extensor digitorum longus in the leg
- Bipennate= the fibres are arranged in a V-shape and insert onto both sides of the tendon eg- recuts remoris in the thigh
- Multipennate= these look like multiple bipennate muscles side by side eg- deltoid in the shoulder.
What is a motor unit?
A motor unit is composed of a single motor neuron, its axon and the muscle fibres it supplies.
There can be great variation in the size of motor units. In the small muscles that move the eyeball, a single motor nerve axon may only supply just a few muscle fibres, allowing fine control of eye movement. In contrast in the thigh muscles a motor unit may comprises thousands of muscle fibres giving the muscle power but less precision.
What does the upper limb consist of
The arm, forearm and Hand
What does the lower limb consist of?
The thigh, leg and foot
What is the gross anatomy of the upper and lower limbs
- A ball and socket joint where limbs meet the trunk/torso
-one large bone in the proximal - one hinge joint that separates the proximal and middle parts
- two bones in the middle part
- A collection of smaller bones at the start of the sitar part
-five digits
-One digit considerably larger - most of the muscle mass concentrated proximally
How has the upper limb evolved for dexterity?
The upper limb has evolved for dexterity and therefore is more mobile by
- the shoulder joint has only a shallow socket and lax ligaments which allow for a wider range of movement for positioning the hand
-the fingers/digits are long able to perform complex movements
How has the lower limb evolved for bipedal locomotion and to support body weight?
-The hip joint has a deep socket with strong ligaments so its stable but less mobile than that of the shoulder joint
- the foot and toes are adapted for weight-bearing rather than dexterity
The Vertebral Column
The vertebral column also known as spine or spinal column, spans from the base of the skull to the cocoyx.
The spine supports the head, neck and trunk/torso, protects the spinal cord, provides attachments for muscles and allows movement.
There are 33 vertebrae found in the vertebral column which are split into 5 sections
- Cervical= 7 vertebrae in the neck C1-7
- Thoracic= 12 vertebrae in the thorax T1-12
- Lumbar= 5 vertebrae in the abdomen L1-5
- Sacral= 5 vertebrae in the pelvis S1-5 which are fused to the sacrum
- Coccygeal= 4 vertebrae in the pelvis Co1-4 which are fused to the cocccyx
The vertebral column is not straight instead curved which helps to absorb shock. The cervical and lumbar segments curve anteriorly, forming a cervical lordosis and lumbar lordosis.
The thoracic and sacral segments curve posteriorly forming a thoracic kyphosis and sacral kyphosis
How are vertebrae in the vertebral column connected
Small synovial facet joints, intervertebral discs and several groups of ligaments connect all vertebrae to each other
What do intervertebral discs do between vertebrae
Intervertebral discs between vertebrae support the weight of the upper body and absorb shock
What are distinguishing features of the cervical vertebrae
Cervical vertebrae have bifid spinous processes, holes in the transverse processes and oval shaped bodies. The first two are uniquely modified for rotation of the head.
What are the distinguishing features of Thoracic vertebrae
The thoracic vertebrae have long sharp, downward-sloping spinous processes that overlap the vertebrae below. Additional articular facets for the attachment of ribs and heart shaped bodies
What are the distinguishing features of the lumbar vertebrae
The lumbar vertebrae are short, blunt, spinous processes and extra large oval-shaped bodies to support the weight of the body.
What are the distinguishing features of sacral vertebrae
Sacral vertebrae are fused into the sacrum, a triangular-shaped bone that sits in the posterior midline. It articulates with the left and right hip bones to form the bony pelvis
What are the distinguishing features of the coccygeal vertebrae
The coccygeal vertebrae are fused to form the coccyx which is a vestigial remnant of what used to be a tail
What are we taking about in terms of the pectoral girdle
This describes the clavicle, the scapula and the muscles which attach to these bones
When taking about the arm, what are we talking about
The arm is the region between the shoulder and the elbow joints.
The arm contains the humerus along with anterior and posterior muscle compartments
When taking about the forearm what are we talking about
This is the region between the elbow and the wrist joint
The bones of the forearm are the radius and the ulna with anterior and posterior muscle compartments
When when talking about the hand what are we talking about
The hand lies distal to the wrist. The hand is spoken about in terms of the palm and the dorsal
What is the glenohumeral joint
What type of joint is it
How is it formed
How mobile is this joint
The shoulder joint
This is a synovial ball and socket joint
This is formed by the articulation between the scapula and the proximal humerus
Highly mobile
What does the elbow joint allow for
What type of joint is this
How is it formed
It allows flexion and extension of the forearm
It is a synovial hinge joint
It is formed by the articulation of the distal humerus with the ulna and radius
What type of joints are the proximal and distal radioulnar joints
What do these joints allow
These are synovial joints
They allow for pronation and supination of the forearm and hand
What is the radiocarpal joint
What type of joint is this
How is it formed
What does this joint allow
The wrist joint
Synovial joint
Formed by the articulation between the distal radius and the two carpal bones of the wrist
This allows for flexion, extension, abduction and adduction
What is the anterior movement of the pectoral girdle called with an example
Protraction
We do this when we reach out our arm to open a door
What is the posterior movement of the pectoral girdle called and give an example
Retraction
Squaring the shoulders
What movements can be done via the shoulder joint
Flexion, extension, abduction, adduction, medial rotation, lateral rotation and circumduction.
What movements can be seen with the elbow joint
Flexion and extension
What movements can be observed with the radioulnar joint
Pronation and supination
What movements can be seen from the wrist joints
Flexion, extension, abduction, adduction
What movements can be seen from the fingers
Flexion, extension, adduction, abduction
What does the clavicle articulate with
The clavicle articulates with the sternum at the medial end via the sternoclavicular joint
The clavicle articulates with the acromion of the scapula at the lateral end via the acromioclavicular joint
Both joints are synovial
What is the clavicle for
The clavicle holds the limbs away from the trunk so that they can move freely
What is the posterior surface of the scapula like
The posterior surface bears a ridge of bone called the spine which is usually easily palpable
Where is the acromion found
The lateral end of the spine expands to form the acromion which articulates with the lateral end of the clavicle
What forms the pectoral girdle
The clavicle, the scapula and the associated muscles
What is the glenoid fossa
This is the shallow fossa on the lateral aspect of the scapula
What does the glenoid fossa articulate with
The glenoid fossa articulates with the proximal humerus to form the should joint
What is the shoulder joint also known as
The glenohumeral joint
Why is the shoulder joint an unstable joint
The glenoid fossa is shallow making it a poor fit for the humerus to fit into, this increases the range of movement that the shoulder can do and so compromises the stability of the joint
What can be found superior and inferior to the glenoid fossa
2 small projections of bones known as the supraglenoid tubercle and the infraglenoid tubercle
Why are the supraglenoid and infraglenoid tubercles important for
Muscle attachements
What is the humerus
The long bone of the arm
What does the head of the humerus articulate with
The glenoid fossa of the scapula
What is the anatomical neck
This is the groove in the head of the humerus
What is the greater tubercle
This si a projection of bone off the proximal humerus
What is the greater tubercle important for
Muscle attachements
What is the surgical neck
This is where the bone of the humerus narrows and becomes continuous with the shaft just distal to the tubercles
Why is the surgical neck clinically important
This area is commonly fractured especially seen in the elderly when they fall and because the axillary nerve runs close to the region and can be injured by any fractures of the surgical neck or dislocations of the humeral head
What is the deltoid tuberosity
This is a slight pro tuba c4 of the humeral shaft on the upper lateral aspect
What is the deltoid tuberosity for
For the deltoid muscle to attach to
What is the radial groove
This is a groove which marks the path of the radial nerve over the posterior aspect of the upper part of the humeral shaft
Why can the radial nerve become injured
The radial nerve runs very close to the humerus and so can be injured in mid-shaft humeral fractures
Where is the scapula found
On the posterior chest wall
What are the movements of the scapula
With examples
Protraction- extend the arm out to push open a door
Retraction- squaring the shoulders
Elevation- shrugging the shoulders
Depression- lowering the shoulders
Rotation- this tilts the glenoid fossa cranially to aid elevation of the upper limb
Why is rotation of the scapula important
When raising the arm above the head for every 2 degrees of abduction of the shoulder the scapula rotates 1 degree
What determines the direction in which the scapula can move when muscles contract
The attachments points of the muscles and the orientation of the muscle fibres
What is the key muscle involved in protraction
Serratus anterior
What are the 2 large superficial muscles of the posterior pectoral girdle
The trapezius
The latissimus dorsi
Where does the trapezius and latissimus dorsi attach to
They have extensive attachments to the vertebral column
Does the latissimus dorsi attach to the scapula
No it doesn’t, the latissimus dorsi attaches to the anterior aspect of the proximal humerus so it moves the shoulder joint rather than the scapula
Does the trapezius only attach to the vertebral column
No it attaches the the vertebral column and the skull
What 3 muscles attach the medial border of the scapula to the vertebral column
The lavator scapulae
The rhomboid major
The rhomboid minor
What movement os produced of the scapula when the trapezius contracts
Upper part- elevates
Middle part- Retracts
Lower part- Depresses, rotates the scapula
What movement is produced when the latissimus dorsi contracts
This extends, adducts and medially rotates the humerus
What movement is produced when the levator scapulae contracts
This elevates the scapula
What movement is produced when the rhomboid major contacts
It retracts the scapula
What movement is produced when the rhomboid minor contracts
It retracts the scapula
What is the origin of the trapezius
The skull, cervical and thoracic vertebrae
What is the insertion of the trapezius
Clavicle and scapula (spine and acromion)
What is the origin of the latissimus dorsi
Lower thoracic vertebrae
What is the insertion of the latissimus dorsi
The upper anterior of the humerus
What is the origin of the levator scapulae
Upper cervical vertebrae
What is the insertion of the levator scapulae
Medial border of the scapula
What is the origin of the rhomboid minor
C7 and T1
What is the insertion of the rhomboid minor
The medial border of the scapula
What is the origin of the rhomboid major
Thoracic vertebrae
What is the insertion of the rhomboid major
The medial border of the scapula
What are most of the muscles of the posterior pectoral region innervated by
By branches that arise from the brachial plexus
Which muscle of the posterior pectoral region isn’t innervated by nerve of the brachial plexus
The trapezius is not innervated by the brachial plexus but instead is innervated by the 11th cranial nerve known as the accessory nerve
What is the latissimus dorsi innervated by
The latissimus dorsi is innervated by a branch of the brachial plexus known as the thoracodorsal nerve
What six muscles attach the scapula to the humerus
Deltoid
Supraspinatus
Infraspinatus
Subscapularis
Teres minor
Teres major
What are the 4 rotator cuff muscles
Supraspinatus
Infraspinatus
Subscapularis
Teres minor
Where can the deltoid muscle found
The deltoid is the large muscle found over the lateral aspect of the shoulder
Where does the deltoid muscle attach to
The deltoid muscle attaches the humerus to the lateral part of the clavicle to the spine of the scapula
Where does the deltoid muscle insert
The deltoid muscle inserts onto the humerus at the deltoid tuberosity
What is the role of the deltoid muscle
It is a powerful abductor of the shoulder joint
Can the deltoid muscle initiate abduction
No the deltoid muscle cannot initiate abduction, another muscle initiates the first 20 degrees before the deltoid takes over
What does the deltoid muscle do to the shoulder joint
The anterior and posterior fibres of the deltoid muscle contribute to the flexion and extension of the shoulder joint
What is the deltoid muscle innervated by
It is innervated by a major branch of the brachial plexus called the axillary nerve
What can injury to the axillary nerve cause
Weakness and atrophy or even paralysis of the deltoid muscle which would impact the ability to move the shoulder joint
What is the origin of teres major
This muscle arises from the posterior aspect of the scapula
Where does teres major insert
Teres major inserts on the anterior aspect of the humerus
What movements can be made by the contraction of the teres major
Medial rotation and adduction of the shoulder joint
Where do the rotator cuff muscles attach
The rotator cuff muscles attach the scapula to the tubercles of the humerus
Where do the Supraspinatus, Infraspinatus and teres minor all originate
The origin of all 3 of these muscles is the posterior surface of the scapula
Where do the Supraspinatus, Infraspinatus and teres minor all insert
They all insert onto the greater tubercle
Where dose the tendons of the the Supraspinatus, Infraspinatus and teres minor fuse
All the tendons fuse with the fibrous capsule that surrounds the shoulder joint
What is the quadrilateral space
This is a square-shaped space bounded by the teres minor above, teres major below and the long head of the triceps medially and the surgical neck of the humerus laterally
What travels through the quadrilateral space
The axillary nerve travels through this space so it can enter the posterior scapula region and innervate the deltoid and teres minor
What is the origin of the Subscapularis
This muscle originates from the anterior surface of the scapula
Where does the subscapularis insert
This muscle inserts on the lesser tubercle of the humerus
What is the action of the deltoid muscle at the shoulder joint
Abduction beyond 20 degrees
Whar is the origin from the scapula of the deltoid muscle
The spine, acromion and clavicle
What is the insertion of the deltoid muscle on the humerus
The deltoid tuberosity
What is the action of the teres major at the shoulder joint
Medial rotation and adduction
What is the origin of the teres major from the scapula
The posterior surface, inferior part of the lateral border
What is the insertion of the teres major on the humerus
The anterior humerus
What is the action of the supraspnatus at the shoulder joint
The first 20 degrees of abduction
What is the origin of the supraspinatus from the scapula
The supraspinous fossa
What is the insertion of the supraspinatus on the humerus
The greater tubercle= superior facet
What is the action of the infraspinatus at the shoulder joint
Lateral rotation
What is the origin of the infraspinatus from the scapula
The infraspinous fossa
What is the insertion of the infraspinatus on the humerus
The greater tubercle= middle facet
What is the action of the teres minor at the shoulder joint
Lateral rotation
What is the origin of the teres minor from the scapula
The lateral border
What is the insertion of the teres minor on the humerus
The greater tubercle= inferior facet
What is the action of the subscapularis at the shoulder joint
Medial rotation
What is the origin of the subscapularis from the scapula
The Subscapular fossa
What is the insertion of the subscapularis on the humerus
The lesser tubercle
Why is supraspinatus clinically impaortant
This muscle is clinically important because as it travels from the suprasinous fossa to the greater tubercle it travels under the acromion. The tendon may become inflamed and pinched between the humerus and the acromion during movements of the shoulder. This is called impingement and patients would present with a painful arc
What allows for good range of movements at joints
The poor fit of articulating surfaces facilitated by loose joint capsules
What is the role of the rotator cuff muscles
They provide vital stability for the shoulder joint which compensates for the poor fitting articulating surfaces
What does contraction of the rotator cuff muscles do
Contraction of the rotator cuff muscles hold the head of the humerus in the shallow glenoid fossa
What is the glenoid labrum
This is a rim of fibrocartilage around the margin of the glenoid fossa to contribute to stability by deepening the shallow fossa
What is the inter muscular septa
This extends from the deep brachial fascia separating the arm into anterior and posterior compartments
What is the triceps brachii
This is a single large muscle that lies in the posterior compartment of the arm
What are characteristics of the triceps brachii
It has 3 muscle bellies/heads which all converge via a common tendon onto a single insertion point
What is the insertion point of the tricep brachii
The olecranon of the ulna
When the tricep brachii contacts what does this cause and why
When the tricep brachii contacts it causes the elbow to extend due to the muscle crossing the posterior aspect of the elbow joint
What are the names of the 3 heads of the tricep brachii
Long head
Lateral head
Medial head
Where does the long head of the tricep brachii originate from
The long head of the tricep brachii originates from the infraglenoid tubercle of the scapula and is the most medial part of the tricep
Where does the lateral head of the tricep brachii originate from
The lateral head originates from the posterior humerus proximal to the radial groove
Where does the medial head of the tricep brachii originate from
The medial head originates from the posterior humerus distal to the radial groove
Why can the long head of the tricep brachii contribute to extension of the shoulder joint
Due to its attachements to the scapula
What are all 3 parts o the tricep brachii innervated by
They are innervated by the radial nerve
Where does the radial nerve run
The radial nerve winds around the posterior aspect of the humerus in the radial groove between the medial and lateral heads of the tricep brachii
What is adhesive capsulitis
Frozen Shoulder
What is the main symptoms of adhesive capsulitis
Pain and stiffness in the shoulder
What is the cause of adhesive capsulitis
The capsule of the joint becomes inflamed, stiff and tight, adhesions may develop.
Who is more likely to get adhesive capsulitis
Middle age people more common with women and people who suffer with diabetes
What is the treatment for adhesive capsulitis
There is no cure for this but supportive treatments of physiotherapist is the main treatment but can take up to 3 years to resolve.
What can cause rotator cuff injury
Acute trauma or repetitive use but can also be cause due to degeneration of the muscles due to age
What happens if the supraspinatus tendon becomes injured
If this tendon becomes injured or inflamed it may become impinged between the acromion and the humeral head, this would mean that the first part of abduction would be normal but between 60 and 120 degrees of abduction the patient would experience pain, after 120 degrees the pain would subside this is what is known as a painful arc. If left untreated the inflamed tendon may rupture
What has happened if someone dislocated there shoulder
In a shoulder dislocation the humeral head moves out of the glenoid fossa
What type of dislocation Is most common of the shoulder
An anterior dislocation is most common and almost all dislocations will be anterior
What usually causes a dislocation to the shoulder
Blunt force trauma eg-fall
Why is a posterior dislocation usually missed
This is usually missed due to it been very uncommon
What causes a posterior shoulder dislocation
Usually associated with vigorous muscle contraction eg- epileptic seizure
What can a dislocation of the shoulder cause injury to
The axillary nerve
Why can the axillary nerve become injured
Because it lies close to the surgical neck of the humerus so can be injured by fractures in this region or dislocation of the shoulder
Why would injury to the axillary nerve cause weakness to the deltoid muscle
Injury to the axillary nerve can result in weakness or paralysis of the deltoid due to the motor fibres of the axillary nerve innervate the deltoid and teres minor, if this is injured this presents functionally as difficultly abducting the shoulder
What causes weaknesses of the tricep
The radial nerve travels along the radial groove of the posterior humerus. Fractures of the humeral shaft can injury the nerve. This can lead to weakness or paralysis of the muscles that are innervated by the radial nerve
What are the bony prominences called that expend dismally from the shaft
The medial and lateral epicondyles
Where are the trochlea and capitellum
There a prominences found on the distal humerus
What does the trochlea and capitellum articulate with
They articulate with the trochlear notch of the ulnar and the head of the radius at the elbow joint
What is the axilla
The armpit
What is the armpit
The space between the trunk and the upper arm
How many boundaries does the axilla have
6
What are the 6 boundaries of the axilla
Anterior wall
Posterior wall
Lateral wall
Medial wall
Apex
Base
What makes up the anterior wall of the axilla
Pectoralis major and minor
What makes the posterior wall of the axilla
Subscapularis, teres major and latissimus dorsi
What makes up the lateral wall of the axilla
Upper humerus
What makes up the medial wall of the axilla
Serratus anterior and chest wall
What makes up the apex of the axilla
First rib, clavicle, scapula
What makes up the base of the axilla
Skin and fascia between the chest wall and arm
What does the axilla contain
Fat
Lymph nodes
Axillary artery
Axillary vein
Brachial plexus
How many groups of lymph nodes are found in the axilla
5 groups
What do the lymph nodes drain in the axilla
The lymph nodes in the axilla drain the upper limb, breast, chest wall, scapular region and the abdominal wall as far as the umbilicus
Where are the lymph nodes in the axilla located
They are located in the apex
What are the lymph nodes in the axilla also known as
The apical nodes
What are the lymph nodes usually involved in
They are usually involved in the spread of cancer due to them draining lymph from a large area
What type of cancer are the lymph nodes usually associated with
Breast cancer
What might be a first sign of breast malignancy
A lump in the armpit
What 2 things could a lump in the armpit mean
Infection
Breast malignancy
What is the axillary artery a continuation of
The subclavian artery
What does the axillary artery become
The brachial artery
What does the axillary artery give rise to
The axillary artery gives rise to several branches above the pectoralis minor- 2 behind and 3 in front
When does the axillary artery become the brachial artery
The axillary artery becomes the brachial artery when it crosses the inferior border of the teres major
What is the axillary vein
This is a large vein which drains the upper limb
What is the axillary vein a continuation of
The axillary vein is a continuation of the subclavian vein
How is the axillary vein formed
The axillary vein is formed by the union of the deep veins of the arm with the basilic vein
Penetrating wounds of the axilla could be life-threatening, how can the bleeding be stopped here
Compressing the vessels against the humerus
What is the brachial plexus
This is a network of nerves that provides motor and sensory innervation to the upper limb
What is the brachial plexus formed by
The brachial plexus is formed by spinal nerves that leave the lower cervical spinal cord segments and the first thoracic spinal cord segment.
These are spinal nerves C5,C6,C7,C8 and T1
Mixture of nerves which carry motor and sensory fibres
How many segments is the brachial plexus split into
5 segments
What are the 5 segments of the brachial plexus
Roots
Trunks
Divisions
Cords
Branches
What are the roots of the brachial plexus
The roots of the brachial plexus are the 5 spinal nerves C5-T1 that exit the spinal cord and collectively give rise to the brachial plexus
These are found in the neck
Where is the trunks of the brachial plexus found
In the neck
What makes up the trunks of the brachial plexus
C5 and C6 combine to form the superior trunk
C7 continues as the middle trunk
C8 and T1 combine to form the inferior trunk
What are the divisions of the brachial plexus
Each trunk then divides into a posterior and anterior division under the clavicle
What are the cords of the brachial plexus
Anterior divisions of the superior and middle trunks combine to make the lateral cord
Posterior divisions of all the trunks combine to make the posterior cord
Anterior divisions of the inferior trunk continue as the medial cord
What branches of the brachial plexus are located in the axilla
Axillary branch
Radial branch
Musculocutaneous branch
Ulnar branch
Median branch
Where does the axillary branch arise from
The posterior cord
What does the radial branch arise from
The posterior cord
Where does the musculocutaneous branch arise from
The lateral cord
Where does the ulnar branch arise from
The medial cord
Where does the median branch arise from
They arise from the lateral and medial cords
As well as giving rise to the terminal branches in the axilla the different segments of the brachial plexus give rise to other nerves which innervate what
The shoulder and the pectoral muscles
What does the axillary nerve innervate
The deltoid and teres minor and small regions of the skin over the upper lateral arm
Where does the axillary nerve arise from
It is a branch of the posterior cord
What spinal nerves does the axillary nerve contain
C5 and C6
Where does the axillary nerve run
It runs close to the surgical neck of the humerus and is vulnerable to injury through fractures of the surgical neck or dislocations of the humeral head
What does the radial nerve innervate
It innervates the tricep in the posterior arm, and innervates all the muscles in posterior compartment of the forearm, these muscle are extensors of the wrist and digits
What is the radial nerve a continuation of
The radial nerve is a continuation of the posterior cord
What spinal nerves does the radial nerve contain
C5-T1
Where does the radial nerve run
It runs along the radial groove on the posterior surface of the humerus and is vulnerable to mid-shaft fractures
What does the musculocutaneous nerve innervate
The musculocutaneous nerve innervates the 3 muscles in the anterior arm
Where does the musculocutaneous nerve arise from
The musculocutaneous nerve arises from the lateral cord
What spinal nerves does the musculocutaneous nerve contain
C5-C7
What does the musculocutaneous nerve continue as
The musculocutaneous nerve continues as a sensory nerve that innervates a region of the skin over the forearm
What do the median and ulnar nerves innervate
These 2 nerves don’t innervate any muscles in the arm, these innervate muscles in the anterior forearm and hand
How is the median nerve is formed from the contribution of what
The median nerve is formed from the contributions from both the lateral and medial cords
What spinal nerves does the median nerve contain
C6-T1
What does the median nerve innervate
The median nerve innervates most of the muscles of the anterior forearm which are the flexors of the wrist and digits, along with innervation the small muscles of the thumb and the skin over the lateral aspects of the palm of the hand and over the lateral digits
Where is the median nerve at its most vulnerable
The median nerve is most vulnerable in the arm as it crosses the anterior aspect of the elbow known as the cubital fossa
How is the ulnar nerve formed
The ulnar nerve is formed by the continuation of the medial cord after it has given a contribution to the median nerve
What spinal nerves are found in the ulnar nerve
C8-T1
What does the ulnar nerve innervate
The ulnar nerve innervates most of the small muscles in the hand and is vital for fine movements of the digits. It also innervates skin over the medial aspect of the hand and medial digits
Where is the ulnar nerve most vulnerable
The ulnar nerve is most vulnerable to injury behind the medial epicondyle as it lies most superficially here
What is the most catastrophic type of brachial plexus injury
The most catastrophic brachial plexus injury occurs when all 5 roots of the brachial plexus are injured, this is uncommon but devastating as it effectively denervates the whole upper limb
What are the 3 muscles found in the anterior compartment of the arm
Biceps brachii
Brachialis
Coracobrachialis
What are are all 3 muscles in the anterior compartment of the arm
All 3 are flexors
All 3 are innervated by the musculocutaneous nerve
What are the characteristics of the biceps brachii
Lies most superficially in the anterior arm
2 muscle bellies
What are the 2 muscle bellies of the bicep brachii
The long head
The short head
Proximally what are both muscle bellies attached to
The scapula
Apart from the scapula what does the long head attach to
The supraglenoid tubercle
Apart fro the scapula what else does the short head attach to
The Coracoid process
What doe the 2 muscle bellies of the bicep brachii converge onto
The 2 muscle bellies converge via a common tendon onto the radial tuberosity of the radius
How does the long head of the bicep brachii help to stabilise the shoulder joint
The tendon of the long head of the bicep pierces the capsule of the shoulder joint to help and stabilise it
What type of muscle is the bicep
The bicep is a flexors of the elbow joint but because it crosses the shoulder joint it can contribute to flexion of the shoulder joint
Where is the brachialis located
The brachialis is located deep to the bicep
What does the brachialis attached to
The brachialis is proximally attached to the anterior aspect of the lower half of the shaft of the humerus
Where does the brachialis insert
The brachialis crosses over the the elbow joint and inserts distally upon the ulna tuberosity.
What type of muscle is the brachialis
The brachialis is a powerful flexor of the elbow joint
Where is the caracobrachialis found attached to
The coracobrachialis is a smaller muscle that attaches proximally to the coracoid process of the scapula and distally to the medial aspect of the middle part of the humerus
Where does the coracobrachialis cross over
The coracobrachialis crosses the shoulder joint and acts upon it as a weak flexor
What is the cubital fossa
The cubital fossa is a region anterior to the elbow joint
How many borders does the cubital fossa have
3
What were the 3 borders if of the cubital fossa
The lateral border
The medial border
The superior border
What is the lateral border of the cubital fossa made up of
The lateral border is formed by brachioradialis a posterior forearm muscle
What is the medial border of the cubital fossa made up of
The medial border is formed by the pronator teres which is an anterior forearm muscle
What is the superior border of the cubital fossa made up of
The superior border or base of the cubital fossa is formed by an imaginary line drawn between the medial and lateral epicondyles of the humerus
What is the apex of the cubital fossa
The apex is the most distal part of the cubital fossa and pointing towards the forearm and hand
Can the tendon of the bicep brachii found in the cubital fossa
The tendon of the bicep can be traced through into the cubital fossa as it travels to its insertion point on the radial tuberosity
What is the bicipital aponeurosis
This is a fascial extension of the biceps tendon
What is the role of the bicipital aponeurosis
It seperates the superficial veins from the deeper structures in the cubital fossa: the brachial artery and the median nerve
Where is the brachial artery located
The brachial artery lies medial to the biceps tendon
What does the brachial artery become
The brachial artery bifrucates into its terminal branches the radial and ulnar arteries in the cubital fossa
Where is the median nerve found
The median nerve lies medial to the brachial artery
Where is the radial nerve located
The radial nerve is found deep to the brachioradialis
Why are the superficial veins in the cubital fossa clinically important
The superficial veins are clinically important for venipuncture and intravenous access
When axillary lymph nodes are removed what 2 nerves could be at risk of injury
The long thoracic nerve
The throacodorsal nerve
What does the long thoaracic nerve innervate
The serratus anterior
What would be caused by injury to the long thoracic nerve through axillary lymph node removal
Injury to this nerve causes weakness or paralysis of serratus anterior which would cause the scapula to appear raised up due to the medial border of the scapula not sitting flat on the posterior chest wall, this is known as winged scapula
Why is the throacodorsal nerve vulnerable to injury in the removal of the axillary lymph nodes
The thoracodorsal nerve to the latissimus dorsi is vulerable as it runs along the subscapularis muscle which forms the posterior wall of the axilla
Why is the ulnar nerve vulnerable to injury
The ulnar nerve is vulnerable to injury in the lower arm as it travels behind the medial epicondyle. If the medial epicondyle is fractured the nerve may be injured. Injury to this nerve can lead to motor impairment of the hand as it innervates most of the small muscles of the hand along with causing sensory impairment in the hand.
What is upper brachial plexus injury also known as
Erb’s palsy
What causes Erb’s palsy
This injury in uncommon.
The upper parts of the brachial plexus are affected which can involve the C5-C6 or C5-C7
This injury occurs with paralysis of one of the lateral rotators of the shoulder and the extensors of the wrist, the affected limb will typically appear medially rotated and wrist flexed
What usually causes Erb’s Palsy
It it typically caused by trauma where the head is stretched away from the shoulder so typically seen when someone is thrown from a motorbike or horse or in newborns if a baby’s shoulder becomes stuck and the neck is extensively stretched
What is lower brachial plexus injury also known as
Klumpke’s Palsy
What is Klumpke’s Palsy
This is another uncommon injury where the lower parts of the brachial plexus are affected C8-T1
This is where the small muscles in the hand become paralysed
What causes Klumpke’s Palsy
It is typically caused by trauma where the arm is forcefully pulled upwards which stretches the nerves of the plexus
Can be seen in babies during delivery if the arm is forcefully pulled
What is horners syndrome
Horners syndrome is seen through 3 main symptoms including drooping of the eyelid, constriction of the pupil and lack of sweating
What causes horners syndrome
It is caused when the sympathetic nerve supply to the face is interupted. T1 spinal nerve carries sympathetic fibres which are destined to supply the face but if an injury occurs in the brachial plexus to T1 horners syndrome would occur
What is a brachial plexus block
This is a form of regional anaesthesia which can be used as an alternative to general anaesthetic for surgery of the upper limb
How does a brachial plexus block work
The anaesthetic is injected via the help of ultrasound guidance around the nerves of the brachial plexus which anaesthetises the upper limb which is checked before surgery commences via tests of sensory and motor function
What are the 2 bones of the forearm
Radius
Ulnar
How are the radius and ulnar bones connected in the forearm
They are connected by the interosseous membrane
What do the radius and ulnar articulate at there proximal ends
They articulate with the distal humerus at there proximal ends
What does the articulation of the ulnar and radius with the humerus form
The elbow joint
What does the trochlea notch of the ulnar articulate with
It articulates with the trochlea of the humerus
What does the radial head articulate with
It articulates with the capitellum of the humerus
What movements can occur at the elbow joint
Flexion and extension
Where do the radius and the ulnar articulate with each other
They articulate with each other at the radioulnar joints
What movements does the radioulnar joints allow for
Pronation and supination of the forearm and hand
What forms the radiocarpal joint
The radius articulates with 2 small bones of the wrist forming the radiocarpal joint
What movement is permitted at the radiocarpal joint
Flexion
Extension
Abduction
Adduction
How many bones is the carpus made up of and how are they arranged
8 small bones which are roughly arranged in 2 rows one proximally and one distally
What bones does the distal radius articulate with in the carpal
The distal radius articulates with 2 bones in the proximal row of the carpal, the scaphoid and lunate, which forms the radiocarpal joint
What does the proximal row of the carpal bones consist of
Scaphoid
Lunate
Triquetral
Pisiform
Which bone of the proximal row of the carpals isn’t considered as a true bone and why
The pisiform isn’t considered as a true bone but more of a small bone that develops in the tendon of the flexor carpi ulnaris
What does the distal row of the carpal consist of
Trapezium
Trapezoid
Capitate
Hamate
What is the hook
A Bony prominent on the hamate which you can palpate
What is the most commonly fractured carpal bone
The scaphoid
How is the scaphoid bone most commonly fractured
Usually done by a fall onto an outstretched hand
Where are the metacarpals
They lie distal to the carpus
What are the bones of the digits
The phalanges
How many phalanges are in each finger and thumb
3 in each finger
2 in the thumb
What is the cubital fossa bound laterally and medially
The cubital fossa is bound laterally by the brachioradialis and laterally by the pronator teres
What is the superior border of the cubital fossa made up of
The superior border is formed by a line between the medial and lateral epicondyles of the humerus
What structures are found in the cubital fossa
Biceps tendon
Median nerve
Brachial artery = the radial and ulnar arteries
Superficial veins
How many muscles make up the anterior compartment of the forearm
8 muscles which are arranged into 3 layers
What are the 3 muscle layers of the anterior compartment of the forearm called
Superficial
Middle
Deep
What are most of the 8 muscles of the anterior compartment of the forearm
Most of them are flexors
What nerve innervates most of the muscles in the anterior compartment of the forearm
Median nerve
How many muscles make up the superficial layer of the anterior compartment of the forearm
4 muscles
What are the 4 muscles of the superficial layer
Pronator teres
Flexor carpi radialis
Palmaris longus
Flexor carpi ulnaris
Where do all the muscles in the superficial layer attach to proximally
They attach to the medial epicondyle of the humerus
What is the medial epicondyle of the humerus usually known as
Common flexor origin
What type of muscle is the pronator teres
It is a pronator
What movement does the flexor carpi radialis allow
Allows for flexion and abduction at the wrist
How can you easily recognise the palmaris longus
It has a small belly but is long and thin
Where does the palmaris longus insert onto
It inserts into the fascia of the palm of the hand
What movement does the flexor carpi ulnaris allow
Flexion and adduction of the wrist
What nerve innervates the flexor capri ulnaris
It is innervated by the ulnar nerve
What muscle forms the middle layer of the anterior compartment of the forearm
The flexor digitorum superficialis
How many tendons does the flexor digitorum superficialis give rise to
4 tendons
What is the function of the muscle, flexor digitiorum superficialis
It is a flexor of the digits
What nerve innervates the flexor digitorum superficialis
It is innervated by the median nerve
How many muscles make up the deep layer of the anterior compartment of the forearm
3 muscles
What 3 muscles of the anterior compartment of the forearm make up the deep layer
Flexor digitorum profundus
Flexor pollicis longus
Pronator quadratus
What is the function of the flexor digitorum profundus
It is a flexor of the digits
Where is the flexor digitorum profundus located
It lies deep to the flexor digitorum superficialis
How many tendons does the flexor digitorum profundus give rise to
It gives rise to 4 tendons
What nerve innervates the flexor digitorum profundus
The muscle is innervated by 2 nerves
The lateral half of the muscle which gives rise to the tendons that travel to the index and middle fingers is innervated by the median nerve
The medial Half of the muscle which gives rise to the tendons that travel to the ring and little fingers is innervated by the ulnar nerve
What is the function of the flexor pollicis longus
Flexion of the thumb
What is the deepest muscle of the forearm
The pronator of the quadratus
What is the function of the pronator quadratus
Pronation of the distal radioulnar joint
What is the carpal tunnel
It is a narrow passageway at the wrist
What makes up the floor and sides of the carpal tunnel
They are formed by the carpal bones
What is the flexor retinaculum
It is a fibrous band that completes the carpal tunnel forming the roof
What does the flexor retinaculum attach to laterally and medially
The flexor retinaculum attaches to the scaphoid and trapezium laterally
The flexor retinaculum attaches to the hook of the hamate and the pisiform medially
What tendons pass through the carpal tunnel
The tendons of the flexor digitorum superficialis
The tendons of the flexor digitorum profundus
The tendons of the flexor pollicis longus
What nerve travels through the carpal tunnel
The median nerve
What would a patent with carpal tunnel syndrome usually present with
Impaired/altered sensation over the skin of the hand so they may experience tingling, numbness or pain
Weakness of the hand muscles supplied by the median nerve so small muscles of the thumb
What can happen if carpal tunnel goes untreated
Thumb may atrophy and weakness may become permanent
How can carpal tunnel be treated
The flexor retinaculum is divided to alleviate pressure
Do the radial artery, ulnar artery and the ulnar nerve travel inside or outside the carpal tunnel
They travel outside the carpal tunnel
Where does the brachial artery bifurcate
The cubital fossa
What are the 2 terminal branches of the brachial artery
The radial artery and the ulnar artery
Where does the radial artery run
The radial artery runs along the lateral aspect of the forearm
Where can the redial artery be palpated
The wrist
Where does the ulnar artery travel
The ulnar artery runs down the medial aspect of the forearm
Where can the ulnar artery be palated
In the wrist
Why is the ulnar artery harder to palpate than the radial artery
It may be partially covered by the tendon of the flexor carpi ulnaris
