Structural Kinesiology (Biomechanics) Flashcards
What are the 5 types of bones?
Flat bones
Irregular bones
Short bones
Sesamoid bones
Long bones
What are the 6 functions of the skeleton?
Scaffold
Attachment/ lever
Movement
Mineral storage
Blood cell production
Protection
What are the 2 divisions of the skeleton + what do these consist of?
Axial skeleton = thoracic cage, skull
- pectoral girdle
Appendicular Skeleton = pelvic girdle, shoulder girdle, all 4 limbs
What does the pelvic girdle consist of?
Ilium, ischium, pubis which all fuse together to form the sacroiliac joint
What are the 3 key classifications of joints?
- Fixed (fibrous) joints
- Slightly moveable joints
- Moveable (synovial) joints
What are the 6 anatomical classifications + common joint names of the moveable (synovial) joints
Give examples
Enarthrodial = ball + socket = glenohumeral
Ginglymus = hinge = humeroulnar
Sellar = saddle = carpometacarpal
Trochoidal = pivot = radioulnar
Arthrodial = gliding = intercarpal
Condyloidal = ellipsoid = metacarpophalangeal
What are the 2 main joint related structures, explain them
Ligaments = very strong bands of fibrous connective tissue that holds bones of a joint together (BONE TO BONE)
Tendons = tough bands of connective tissue joining MUSCLES TO BONES
How many ribs are there, which are true and which are false - explain
Ribs 1-7 = TRUE RIBS = attached directly to sternum by costal cartilages
Ribs 8-12 = FALSE RIBS = attached indirectly to costal cartilages above (8-10) and some ‘floating’ (11-12)
Describe the agonist + antagonist muscles and muscle action during the following movements…
- Hip flexion
- Knee extension
- Dorsi flexion at ankle
- Agonist = iliopsoas, tensor fasciae latae
- Antagonist = gluteus maximus
- muscle action = concentric
- agonist = vastus medialis, intermedius + lateralis
- antagonist = bicep femoris, semi-tendonosus, semi-membranosus
- muscle action = concentric
- agonist = Tib ant
- antagonist = gastrocnemius + soleus
- muscle action = concentric
What are the key features of bone? [12]
- Articular cartilage
- Spongy + epiphyseal bone
- Red bone marrow
- Endosteum
- Compact bone
- Yellow bone marrow
- medullary cavity
- periosteum
- metaphysis
- proximal + distal epiphysis
What are some key skeletal disorders?
- Fractures
- Osteoporosis
- Osteoarthritis
- Rheumatoid arthritis
What are fractures + types?
Determined via snapping/ cracking sounds
- may be deformed
- tender or swollen
- verified via x-rays
Types - closed, open/compound, green-stick, comminuted
Explain what the types of fractures are
Closed = crack in the bone
Open/compound = clean snap of the bone
Green-stick = bone bends and cracks but not into multiple pieces
Comminuted = bone breaks into multiple little pieces
What is osteoporosis?
Loss of bone mass and density that makes the skeleton brittle and prone to fracture
- high impact/ high load activity (running/ resistance training) can attenuate or even reverse decline in bone mass
Age, hormone related changes + calcium deficiency also promotes loss of bone density
What is osteoarthritis?
A degenerative joint disease that can be the consequence of…
- ageing, wear + tear
- A response to traumatic sports injury (ACL rupture)
Primarily due to a deterioration of cartilage producers
- bone growth, ultimately bone spurs that restrict bone movement
- muscle weakness, poor proprioception
What is rheumatoid arthritis?
An autoimmune disorder where the cartilage is attacked
- causes inflammation, swelling and pain
- final stop is fusion of joint
What are the 4 key functions of skeletal muscle?
Producing movement
Maintaining posture
Generating heat
Storing and moving substances
How is movement produced (overview)?
- Force produced by the muscle
- Force is transmitted to the skeleton via the tendon
- Movement occurs/ joint is stabilised/ posture is maintained
What do the following terms mean?
- origin
- Insertion
Origin = tendon attachments nearest the centre of the body
Insertion = tendon attachments furthest from the centre of the body
What are the movement descriptions? Explain
Concentric contraction = muscle is in tension + shortening (lift off for a jump)
Eccentric contraction = muscle is in tension + lengthening (landing of jump)
Isometric contraction - muscle is in tension + remains constant length
What do the following terms mean?
Agonist
Antagonist
Stabilisers
Synergists
- Agonist = muscle responsible for performing or controlling movement
- Antagonist = muscles that could oppose the agonists if activated
- Stabilisers = contract to stabilise nearby joints
- Synergists = assist in action of agonists (guiding muscles)
How is torque calculated?
Force x perpendicular distance from pivot
With regards to rotational movement + torque, what does a longer lever arm have an affect on?
- increases torque
- decreases ROM
- decreases joint angular velocity (speed)
Describe pennate muscles
Muscles with a look of a feather as fibres bed into a tendon that runs the whole length of the muscle with fibres at an angle
- these fibres sacrifice on speed of contraction as there are less sarcomeres in series but maximise on force production as get more sarcomeres in parallel to one another
What are multipennate muscles + what is their advantage?
Insert on multiple tendons tapering towards a common tendon
- advantage is that they can perform a broader range of joint actions
Describe parallel fusiform muscles? Give an example
Sub-category of parallel muscle that has a larger central region called the muscle belly tapering to tendons at each ends (biceps brachii)
- widening of the muscle belly has more sarcomeres in parallel for force production, so these have greater force production capabilities
What are bipennate muscles? Give an example
Pennate muscles with fascicles on both sides e.g. rectus femoris
What are parallel (non-fusiform) muscles?
The direction of the fibres is parallel to the force generating axis, making them useful for fast or explosive movements
- sub-categorised into fusiform + convergent muscles
- e.g. sartorius muscle
What are unipennate muscles?
Have fibres/ fascicle all on one side of tendon
Describe convergent muscles?
They have a broad origin and coverage at their insertion
- have a weaker pull on the attachment due to their broad structure but similarly to multipennate muscles, they are versatile as they can change direction of pull based on region of muscle stimulated
Name the positional descriptor to the description below…
- Closer to midline
- Towards the front
- Away from surface
- Closer to origin
- Sole of foot
- Pertaining the palm
- Further from origin
- Further from midline
- Above/ on top
- Back of hand/ top of foot
- Below/ bottom
- Towards the back
- Towards surface
- Medial
- Anterior
- Deep
- Proximal
- Plantar
- Palmar
- Distal
- Lateral
- Superior
- Dorsal
- Inferior
- Posterior
- Superficial
What are the 3 planes of movement and their corresponding axis of rotation?
Sagittal (left and right) = frontal axis
Frontal (front and back) = sagittal axis
Transverse (top and bottom) = longitudinal axis
Which movements occur at which planes?
Sagittal = flexion, extension
Frontal = abduction, adduction
Transverse = lateral + medial rotation
What are multiplanar movements?
Notably the ball + socket joints of the hip and shoulder have a greater ROM
- at these joints particular movements can occur across more than one anatomical plane
- circumduction, diagonal adduction/ abduction
What is reciprocal inhibition?
Describes the process of muscles on one side of a joint relaxing to allow contraction on the other side of that joint
- activation of motor units of the agonists causes reciprocal neural inhibition of antagonists
- allows lengthening of antagonists under less tension
What are the main functions of the foot and ankle?
- Load bearing
- Locomotion
- Shock absorber
- Lever for propulsion - pivot point to propel us away against ground (2nd class)
What makes up the arches of the foot?
Formed by skeleton and ligaments of the foot
- longitudinal arch
- transverse arch
Describe the longitudinal arch - what is comprises of, role
Comprises of calcaneus, talus, navicular, cuneiforms, metatarsals
- can be high, medium or low
- for weight bearing, balance (lateral side), shock absorption (medial side)
Describe the transverse arch - comprises of, role
Extends across the foot from 1st to 5th metatarsal
- role to play in adapting the foot to uneven surfaces of ground
- foot can be manipulated in transverse plane
What is pes planus and pes cavus?
Pes planus = flat feet
- low arches - softer foot type, good shock aborption, less propulsion, can be caused by excessive eversion
Pes cavus = high arch
- generally a rigid foot type, poor shock absorption but good propulsion
What is the plantar fasciae + what’s the common injury?
A web-like ligamentous structure
- attached to calcaneus, metatarsals, phalanges + skin
- helps support the base of entire foot - including both arches
Plantar fasciitis = injury exhibited as heel pain from overtraining, increased load bearing too quick, increase in activity, obesity, tightness in Achilles
- can lead to inflammation + scarring at point of insertion
What are the 6 joints of the foot and ankle?
- Talocrural joint - ankle
- Subtalar joint - ankle
- Transverse tarsal joint - ankle
- Tarsometatarsal joint - foot
- Metatarsophalangeal joint - foot
- Interphalangeal joint - foot
Describe what makes up the talocrural joint, type, movements + plane
Mortise joint where tibia, fibula, talus articulate
- hinge joint only allowing plantar + dorsi flexion = uniaxial
- movement occurs in sagittal plane + frontal axis
40-50 degrees = plantar flexion
10-20 degrees = dorsi flexion
Describe the subtalar + transverse tarsal joint - type + movements
Gliding joint - allowing for inversion (25 degrees) / eversion (15 degrees) and as a result pronation / supination
what are the 4 compartments to categorise muscles of foot and ankle?
- Superficial posterior
- Deep posterior
- Anterior
- Lateral
Describe the gastrocnemius - compartment, origin, insertion + movements
Superficial posterior
- 2 points of origin - off posterior surfaces of 2 femoral condyle
- inserts into calcaneus
Allows flexion at knee + plantar flexion
Describe the soleus - compartment, origin, insertion + movements
Superficial posterior
- originates off posterior surface of head of fibula + upper Half of posterior surface of tibia
- inserts into calcaneus
Line of pull only passes joint at ankle - not knee
- allows plantar flexion + inversion
Describe the tibialis posterior - compartment, insertion + movements
Deep posterior
- wraps around lower leg medially + inserts to navicular, cuneiform + base of metatarsals
Line of pull similar to soleus = plantar flexion + inversion
Describe the tibialis anterior - compartment, insertion + movements
Anterior
- Sits on the front of the tibia (upper 2/3rds)
- inserts onto most medial cuneiform + little of navicular
Pulls on top of foot + pulls medial side of foot = dorsi flexion + inversion
Describe the extensor hallucis longus - compartment, insertion + movements
Anterior
- middle 2/3rds of anterior fibula
- inserts onto distal hallucis
Pulls on top of foot = dorsi flexion
Pulls on medial side of foot = inversion
Describe the extensor digitorum longus - compartment, origin, insertion + movements
Anterior
- origin is at lateral condyle of tibia and head of fibula
- inserts at end of lesser toes
Dorsi flexion, toe extensor, eversion (pulls on lateral side of foot)
Describe the peroneus longus - compartment, origin, insertion + movements
Lateral
- Origin is upper part of lateral fibula (proximal half)
- inserts under base of foot - comes round lateral side
Foot eversion, plantar flexion (but weak)
Describe the peroneus brevis - compartment, origin, insertion + movements
Lateral
- originates at lateral part of distal half of fibula
- inserts onto base of foot
Foot eversion, plantar flexion (but weak)
Describe the peroneus tertius - compartment, origin + movements
Lateral
- attaches onto distal part of anterior fibula
Eversion + weak contributor to dorsi flexion
What’s are some common injuries to the foot and ankle?
Achilles tendon rupture
Shin splints
Ankle sprains
Describe the symptoms + causes of Achilles tendon rupture
Symptoms = sudden onset of sharp pain in heel, snapping sound, difficulty walking
Causes = sudden dorsi flexion when muscle is in tension, sudden heavy activation of Achilles after prolonged periods of inactivity (atrophy)
What are shin splints?
Small tears/ inflammation of muscles attaching to tibia
What do ankle sprains less commonly occur by?
Via eversion - anatomy means excessive eversion normally results in a different outcome
- once a sprain has occurred, the chance of re-injury increases by roughly 50%
What are the 3 articulating bones and 2 joints of the knee?
Bones = tibia, femur, patella
Joints = tibiofemoral joint, patellofemoral joint
What are the 4 ligaments of the knee?
- Anterior cruciate ligament (ACL)
- Posterior cruciate ligament (PLC)
- Lateral collateral ligament - lateral condyle of femur to head of fibula
- Medial collateral ligament - medial condyle of femur to tibia
What is the medial collateral ligament continuous with?
Medial meniscus
What are the menisci?
A shock absorbing pad
- allows pockets for head of femur to articulate with
- creates stability + lubrication
What type of bone is the patella and where is it?
Sesamoid bone
- embedded in the quadriceps and patella tendon
What’s the functions of the patella?
- Protects anterior knee structure from trauma
- Acts as a lever - increase lever arm of quads
- Provides bony protection
- In high loading impact (squat) - patella dissipates load to reduce tension on tendons by increasing distance from axis of rotation (increases torque of quads)
- 10-30% contribution from quadriceps torque (more in extension)
What makes up the pelvis?
3 sections - ischium (comes out posteriorly), ilium (upper part), pubis (anterior between the 2)
- acetabulum = where head of femur articulates with pelvis
Name the different areas of the ilium
Iliac crest = top of ilium
ASIS = anterior superior iliac spine
AIIS = anterior inferior iliac spine
- these act as bony landmarks + points of attachment
What is the ischial tuberosity?
A large bony prominence acting as a point of anchorage
List the key areas of the femur
Head of femur = articulation point
Greater trochanter = increases torque at hip joint (increases lever arm)
Lesser trochanter = attachment point for iliopsoas muscle
Linea Aspera = line down back of femur (rough) for muscle attachment
List the 4 main muscles that make up the quadriceps group and their origins and insertions
- Rectus Femoris - O: off AIIS and I: tibial tuberosity
- Vastus Medialis - O: off medial femur and I: tibial tuberosity
- Vastus Lateralis - O: off greater trochanter + lateral side of linea aspera and I: tibial tuberosity
- Vastus intermedius - O: anterior surface of femur and I: tibial tuberosity
List the 4 main muscles that make up the hamstrings group and their origins and insertions
- Biceps Femoris - long head - O: ischial tuberosity and I: head of fibula
- Bicep Femoris - short head - O: linea aspera and I: head of fibula
- Semitendonosus - O: ischial tuberosity and I: anteromedial portion of tibia
- Semimembranosus - O: ischial tuberosity and I: medial condyle of femur
- all knee flexors and hip extensors
Apart from the key ones already mentioned, what are the knee flexors?
Gastrocnemius
Popliteus - O: lateral femoral condyle and sits proximal to soleus (contributes to internal rotation)
Sartorius - O: ASIS and I: anteromedial surface of tibia (+ hip abduction and external rotation)
Gracilis - O: ischium + pubis and I: anteromedial tibia (+ hip abduction + flexion + external rotation)
When a muscle with multiple joint actions is activated it attempts to…
Shorten and pull insertion closer to origin
= applying equal force at the O and I, generating torque at both joints, attempting to perform all of its actions
What are the 2 kinds of misalignments of the knee and describe them
Valgus = Knock knees (knees fall inwards)
Varus = bow-legged (knees fall outwards)
What is chondromalacia patella?
Also called runners knee…
- associated with mistracking of patella + damage to patella-femoral cartilage
Risk factors include - valgus knee, pronation, high patella, weak Vastus medialis
How does an ACL rupture occur?
From excessive anterior tibial translation
- during cutting / landing movements
- relatively extended knee joint position
- often some knee valgus
- internal rotation of tibia
- often very soon after ground contact
What are the 4 joints at the pelvic girdle?
Sacroiliac joint - gliding joint between sacrum and ilium
Pubic symphysis - slightly moveable - contains cartilaginous pads between 2 sides of pelvis to prevent collision during impact
Acetabulofemoral joint - ball + socket - between acetabulum and femur
Lumbosacral joint - between 5th lumbar vertebrae + sacrum (last point of articulation of spine)
What is the obturator foramen?
An opening formed by pubis and ischium
What are the 4 main hip flexors?
Rectus femoris
Iliopsoas
Sartorius
Tensor fasciae latae
Describe the origins and insertions of the 4 hip flexors
- Iliopsoas - O: iliacus portion with iliac fossa and psoas portion between T12 - L5 and sacrum and I: at lesser trochanter (top of femur)
- Rectus femoris - O: AIIS and I: tibial tuberosity
- Sartorius - O: ASIS and I: anteromedial tibia
- Tensor fascia latae - O: ASIS and I: iliotibial band + then down to lateral tibial condyle
What are the main hip extensors?
Gluteus maximus
Hamstrings - semimembranosus, semitendonosus and bicep femoris (only long head)
Describe the origins and insertion of the gluteus maximus
- Gluteus maximus - O: 1/4th of crest of ilium and I: oblique ridge on lateral side of greater trochanter
Apart from hip flexion and extension, what are the other movements that can occur and which planes / axis do these occur in?
- Abduction / Adduction - frontal plane, sagittal axis
- Rotation - transverse plane, longitudinal axis
What are the 5 hip adductors?
Adductor brevis
Adductor Magnus
Adductor longus
Pectineus
Gracilis
List the origins and insertions of the 5 hip adductors
- Adductor brevis - O: pubis and I: linea aspera
- Adductor longus - O: pubis and I: linea aspera
- Adductor Magnus - O: pubis + ischial tuberosity and I: linea aspera + medial condyle of femur
- Pectineus - O: anterior pubis and I: inferior of lesser trochanter
- Gracilis - O: pubis and I: anteromedial tibia
What are the main hip abductors and their origins and insertions
Gluteus medius - O: lateral ilium below crest and I: greater trochanter
Gluteus minimus - O: lateral ilium, below GM and I: greater trochanter
What muscles are involved in external rotation of hip?
6 deep external rotators of the hip
- piriformis
- gemellus superior + inferior
- obturator externus + internus
- quadratus femoris
What muscles cause internal rotation of hip?
No real primary muscle - just many contribute
- gluteus minimus
- gluteus medius
- Gracilis
- Tensor Fasciae latae
- semitendonosus
- semimembranosus
Describe Lombard’s paradox?
Describes how we don’t get stuck during sit-stand motion…
- Hip extension + knee extension are occurring
- rectus femoris are agonist for knee extension, but antagonist for hip extension
- hamstrings are agonist for hip extension but antagonists for knee extension
How is Lombard’s Paradox overcome? - what allows us to carry out sit-stand motion
- Extensor muscles at knee + hip have a greater lever arm than flexors
- quadriceps larger muscle is activated to a greater extent than hamstrings
- only part of quadriceps spans the hip (RF) vs all (except BF short head) of hamstrings
All means that there is a net extensor torque at knee which overcomes flexor torque produced at hip and net extensor torque at hip
List some key injuries at the hip region
Femoroacetabular impingement
Iliotibial band syndrome
Hamstrings strain
What is femoroacetabular impingement?
Abnormal growth / deformity of femur / acetabulum
- caused by twisting/ pivoting movements
- causes butting together at end of range
- can damage cartilage of acetabulofemoral joint
- risk factor for hip osteoarthritis
Describe IT band syndrome
IT band is a fibrous reinforcement for tensor fascia latae which if tight…
- inflammation on lateral aspect of knee
- friction between IT band and lateral condyle of femur
Caused by running downhill, running on banked camber and common in breastroke swimmers
What are some risk factors for hamstrings strain?
- Previous hamstring strain
- Fatigue
- Strength imbalance
- Poor flexibility
What are the different regions of the spine (in order) and number of vertebrae for each?
Cervical - 7
Thoracic - 12
Lumbar - 5
Sacrum - 5 (fused)
Coccyx - 4 (fused)
What changes occur as you get further down the spine?
- Vertebral body gets larger
- Spinal processes come down more sharply = limit extension in thoracic region
- Extra facet joints
What type of joints are intervertebral joints?
Slightly-moveable = aphiarthrosis
List and describe the locations of the main joints of the spine
Atlanto-occipital Joint – between atlas + occipital condyles of skull
Atlantoaxial joint – between atlas + axis (pivot joint to turn head left + right)
Intervertebral joint – between intervertebral discs (cartilaginous pads for shock absorption)
Lumbosacral joint – between lumbar + sacrum in pelvic girdle (position of pelvis influences posture of spine)
Describe the key parts of the vertebrae
- Spinous process
- Body
- Vertebral foramen
- Transverse process
- intervertebral foramen between vertebrae + intervertebral disc
What is the ideal posture?
Ears, shoulders, greater trochanter of hip, knees and ankle all line up
- level shoulders + pelvis
- no excessive valgus or varus
- not excessively pronated or supinated
- vertical Achilles tendons
- neutral head position
List the 3 main deformations of the spine
Kyphosis
Lordosis
Scoliosis
Explain what kyphosis is + what its caused by
- forward head position
- hyperextended cervical region
- flexion of thoracic region
- ear line ahead of ‘normal’ and shoulders behind
Typically caused by muscle imbalances + inflexibility (short neck flexors)
Explain what lordosis is and what it’s caused by
- hyperextended lumbar region
- tilt of pelvis (forward) - anteriorly
- weak rectus abdominus relative to lumbar extensors and strong quads relative to hamstrings
What is scoliosis?
Anatomical difference as opposed to imbalances
- uneven shoulders + pelvis
- top of head does not fall at midpoint of feet
- one knee in flexed position - as pelvis is lower on one side)
- curvature of the spine (S-shaped)
How can a bent back during lifting be bad?
It compresses the vertebral discs leading to a herniated disc as everything is pushed to one side of disc
What movements can occur at the spine?
- Lumbar flexion
- Lumbar extension
- Lumbar rotation - to left or right (where thoracic region is facing)
- Lumbar lateral flexion - to left or right (drop shoulders)
What movements can occur at the pelvic girdle?
- Lumbar flexion - anterior pelvic rotation - active
- Lumbar extension - posterior pelvic rotation - active
- Anterior pelvic rotation - lumbar extension - maintain posture
- Posterior pelvic rotation - lumbar flexion - maintain posture
Name the muscles associated at spine
Rectus abdominus
Obliques
Transverse abdominus
What are the posterior muscles at the spine?
Erector spinae (extensor muscles)
- spinalis
- longissimus
- iliocostalis
(All assist in flexion of spine as well)
- quadratus lumborum
Describe the origin and insertion of rectus abdominus + functions
O: crest of pubis
I: cartilage of 5th, 6th, 7th ribs + xiphoid process
Functions…
- both sides = lumbar flexion
- right side = lateral flexion to right
- left side - lateral flexion to left
What is the role of linea alba and tendonous inscriptions?
Linea alba - attachment in middle of rectus abdominus (tendonous structure)
Tendonous inscriptions - divides muscle into pairs = greater control over lumbar flexion
Describe the origin and insertion of obliques + role
External oblique = lumbar rotation to opposite side + lateral flexion to same side
O: lower 8 ribs off side of chest
I: anterior half of crest of ileum
Internal oblique = lumbar rotation to same side + lateral flexion to same side
O: iliac crest
I: costal cartilages of 8th, 9th, 10th ribs
Describe origin and insertions of transverse abdominus and role
O: outer 3rd of inguinal ligament + inner rim of iliac crest
I: crest of pubis
Functions in forced expiration by pulling abdominal wall inward (maintaining abdominal pressure)
- maintains a stable and balanced abdomen during exercise
Describe the origin + insertion of quadratus lumborum + functions
O: posterior inner lip of iliac crest
I: 12th rib and lumbar vertebrae 1- 4
- assist in stabilisation off pelvis + lumbar spine
- core stability
- posture
What is core stability + how does it help?
The ability of muscles of abdomen, particularly deeper postural muscles, to maintain a stable and balanced abdomen + pelvis
- aids performance - solid base for forceful movement of limbs
- being unstable = injury risk due to unwanted movements of pelvis + lumbar spine
- reduces load on spine
What are the risk factors for low back pain?
- Poor posture
- Muscle imbalance
- Poor core stability
What are the key structures involved in the shoulder girdle?
- Scapula
- clavicle
- humerus
- manubrium of sternum
Describe the articulation of the acromioclavicular joint and what this allows…
Articulate is between the acromion process of scapula and the outer end of clavicle
- this allows for greater freedom of movement between the shoulder girdle and shoulder
Describe the sternoclavicular joint - type, movements etc
It’s the only bony connection between the upper appendicular skeleton and axial skeleton
- saddle joint - multiaxial
The movement of the clavicle relative to the sternum in shoulder girdle allows add/abduction and elevation / depression
Outline the anatomy of the scapula - 6 key areas
- Coracoid process
- Acromion process
- Glenoid fossa (articulation for glenohumeral joint)
- Inferior angle
- Scapula spine
- Superior angle
Outline the 6 movements of the shoulder girdle + simply explain
- Elevation + depression - hunching / pushing shoulders down
- Abduction and adduction - moving scapula away from / towards midline
- Upward / downward rotation - inferior angle is moving away / toward midline
Attached to the scapula are 2 groups of muscles involved in movement - what are these groups and outline the muscles within them
Posterior muscles - trapezius, rhomboid, lavator scapulae
Anterior muscles - pectoralis minor, serratus anterior
What muscles makeup the rotator cuff?
Supraspinatus, infraspinatus, teres minor + subscapularis
What are the 3 regions of the trapezius?
Upper fibres
Middle fibres
Lower fibres
Describe the origins and insertions of the 3 regions of trapezius as well as movements they produce
Upper: originate off occipital bone and inserts onto lateral 3rd of clavicle (adduction, elevation)
Middle - originate from C7 to T3 and insert across whole of superior border of scapula spine (adduction)
Lower - originate from T4 to T12 and insert onto triangular space at base of spine of scapula (adduction, depression, downward rotation)
Describe the origin and insertion of the rhomboid + movements
Originates from spinous processes of C7 to T5 and inserts onto medial border of scapula
- elevation, adduction, downward rotation
Describe the origin and insertion of the lavator scapulae + movements
Originates from C1 to C4 and inserts onto point above base of spine of scapula
- elevation, adduction, downward rotation
Describe the origin and insertion of the Pectoralis minor + movements
Originates off anterior surface of ribs 3-5 and inserts onto coracoid process of scapula
- abduction, depression, downward rotation
Describe the origin and insertion of the serratus anterior + movements
Originates from upper nine ribs and inserts onto anterior and medial aspect of scapula
- adduction, upward rotation
What is the role of the nuchal ligament + describe origin / insertion
Originates from occipital pertuberance and inserts onto spinous process of C7
- supports weight of head
- point of attachment for some muscles
Describe an injury to the clavicle
Fractured Clavicle
- most commonly fractured bone in body
- most caused by a direct impact to shoulder
Fracture usually occurs in the middle or towards lateral third
What’s a the treatment for a fractured clavicle?
- rest and minimal movement - use sling
- typically takes 12 weeks to return to full activity
- surgery unusual unless a comminuted fracture
Describe the articulation of the glenohumeral joint
Between the humeral head and glenoid fossa (depression in part of scapula)
List key anatomical landmarks on the superior portion of humerus
Greater tubercule
Lesser tubercule
Intertubercular groove (bicipital groove)
Deltoid tuberosity - point of insertion for deltoid muscle
Explain the discussion between mobility vs stability for the shoulder
Shoulder has a high range of movements
- Rotation can occur in all anatomical planes and axes - maximises MOBILITY but sacrifices STABILITY
Labrum and fibrosis joint capsule ADD stability as well as rotator cuff tendons and glenohumeral ligaments
What are the movements that can occur at the shoulder?
- Backward extension and forward flexion
- Abduction and adduction
- Horizontal abduction and adduction
- Inward rotation and outward rotation (sideways and up/down)
What are the superficial and deep muscles of the shoulder joint
Superficial:
- anterior - pectoralis major
- latissimus dorsi + teres major
- deltoid
- biarticular brachial muscles - biceps and triceps brachii
Deep:
- rotator cuff - supraspinatus, infraspinatus, teres minor + subscapularis
Describe the origin and insertion + muscle movements of latissimus dorsi
Originates off sacrum, posterior part of iliac crest and T6 - L5 and inserts onto medial lip of intertubercular groove of humerus
Actions: adduction, horizontal abduction, extension and internal rotation
Describe the origin and insertion + muscle movements of pectoralis major
Originates off medial half of clavicle and anterior surfaces of costal cartilages and inserts via a flat tendon to outer lip of intertubercular groove of humerus
Actions: adduction, horizontal adduction, internal rotation
Describe the origin and insertion + muscle movements of teres major
Originates off inferior third of lateral wall of scapula and inserts onto medial lip of intertubercular groove of humerus
Actions: adduction, horizontal abduction , extension and internal rotation
What is different about the deltoid muscle?
It consists of 3 portions - anterior, middle and posterior
Describe the origin and insertion + muscle movements of anterior deltoid
Originates off lateral part of clavicle and inserts onto deltoid tuberosity
Actions: abduction, flexion + horizontal adduction
Describe the origin and insertion + muscle movements of middle deltoid
Originates off acromion process and inserts onto deltoid tuberosity
Actions: abduction (greatest for it)
Describe the origin and insertion + muscle movements of posterior deltoid
Originates off spine of scapula and inserts onto deltoid tuberosity
Actions: abduction, extension, horizontal abduction
Describe the origin and insertion + muscle movements of subscapularis
Originates at front of scapula and inserts onto lesser tubercule of humerus
Actions: internal rotation
Describe the origin and insertion + muscle movements of supraspinatus
Originates above spine of scapula and inserts onto head of humerus
Actions: external rotation + weak abduction
Describe the origin and insertion + muscle movements of infraspinatus
Originates below spine of scapula and inserts onto head of humerus
Actions: external rotation
Describe the origin and insertion + muscle movements of teres minor
Originates off lateral border of scapula and inserts onto head of humerus
Actions: external rotation
What are some key injuries of shoulder?
Susceptible to damage from rapid/ ballistic overhead activities
- Muscle / tendon strain - occasional rupture due to excessive forces
- Impingement - due to compression of supraspinatus in subacromial space
- risk factors include… small subacromial space, hypertrophy of supraspinatus, shoulder joint laxity
Describe the origin and insertion + muscle movements of triceps brachii
2 heads - only long head acts in shoulder joint
Long head originates off infraglenoid tubercule of scapula and inserts onto olecranon process of ulna
Actions: extension, adduction, horizontal abduction
Describe the origin and insertion + muscle movements of biceps brachii
Long head originates off supraglenoid tubercule of scapula and inserts onto radial tuberosity
Short head originates off coracoid process of scapula and inserts onto radial tuberosity
Actions: weak shoulder flexion and horizontal adduction
What causes shoulder dislocation?
Caused by excessive abduction and external rotation and impact forcing the humeral head forwards
What are the joints of the upper limbs?
- Shoulder
- Elbow
- Radioulna joints
- Wrist
- Carpo-metacarpal
- Metacarpophalangeal
- Interphalangeal
What movements can occur at the proximal radioulna joint?
Pronation - turning palm to face down
Supination - anatomical position
- angular ligament allows radius to be rotated over ulna
Where does the biceps brachii originate and insert? What movements can occur?
- Long head = originates off supraglenoid tubercule of scapula and inserts onto radial tuberosity
- Short head = originates off coracoid process of scapula and inserts onto radial tuberosity
- flexion of elbow, weak shoulder flexion and horizontal adduction at shoulder
Where does the brachialis originate and insert. What movements?
- Originates a off distal half of anterior portion of humerus
- inserts onto coronoid process of ulna
Allows flexion at elbow
Where does the Brachioradialis originate and insert. What movements?
- originates off distal 2/3rds of lateral condyloid ridge of humerus
- inserts onto radius at styloid process
Permits flexion at elbow, pronation and supination
Where does the Pronator teres originate and insert? What movements?
- originates off medial condyloid ridge of humerus and medial side of proximal ulna
- inserts onto middle third of radius
Pronation and weak flexion of elbow
Where does the Pronator quadratus originate and insert? What movements?
- originates off distal fourth of radius
- inserts onto distal fourth of ulna
Allows pronation
Where does the triceps brachii long head originate and insert and what movements?
- originates off infraglenoid tubercule of scapula
- inserts onto olecranon process of ulna
Permits elbow extension, shoulder extension, adduction and horizontal abduction
Where does the anconeus originate and inserts. What movements?
- originates off posterior surface of lateral epicondyle of humerus
- inserts onto posterior surface of upper ulna and olecranon
Allows extension
Where does the supinator originate and insert?
- originates off lateral epicondyle of humerus
- inserts onto lateral surface of proximal radius
Carries out supination
What are the key joints of the wrist?
- Condyloid joints between radius and scaphoid + lunate
- Carpometacarpal of thumb - saddle joint
List the 7 wrist flexors + the general origin and insertion of these
- Flexor carpi radialis
- Flexor carpi ulnaris
- Pulmoris longus
- Flexor digitorum superfacialis
- Brachioradialis
- Flexor digitorum fundus
- Flexor pollices longus
All originate anteromedially at forearm and insert anterior at hand
And are the 5 wrist extensors + their general origins and insertions?
- Extensor carpi radialis brevis
- Extensor carpi radialis longus
- Extensor digiti minimi
- Extensor digitorum
- Extensor carpi ulnaris
All originate posterolaterally at forearm and insert posteriorly at hand
What are some key injuries of the elbow / wrist?
Tennis elbow
Carpal tunnel syndrome
Ex[lain what tennis elbow is
An overuse injury of wrist extensors / supinators where they attach to the lateral epicondyle of humerus
- likely caused by repetitive wrist extension and supination particularly if eccentric muscle actions are involved
Explain what carpal tunnel syndrome is
Overuse injury and common form of repetitive strain injury
Symptoms = numbness, tingling and decreased sensation in hand
Causes = repetitive and forceful gripping = tendon inflammation within carpal tunnel = compresses the median nerve to the hand
