MSK Flashcards
what are the bones of the upper limb and pectoral girdle (proximally to distally)?
Sternum clavicle, scapula,Humerus, ulnar+ radius, carpals( scaphoid, lunate, triquitum, pisiform, trapizum, trapezioid, capitate, hamate), metacapals (1-5) and phalanges (distal, middle and proximal except in the case of the thumb which only have proximal and distal).
what are the joints of the pectoral girdle?
sternoclavicular and acromioclavicular.
what are the functions of the skeleton?
- Movement and mobility;
- Haemopoeisis;
- calcium and fat stores;
- protection and support
what are the different types of bone?
- long
- short
- sesamoid
- pneumatic
- accessory
- flat
- irregular.
Describe bone formation and growth
Bone formation can occur via intramembranous or endochondral ossification.
Intramembranous ossification: occurs via mesenchyme differentiating into osteoblasts which then grow out from a set point laying down bone.
Endochondral: occurs via a hyaline template that undergoes ossifcation. This occurs first with the chondrocytes swelling so that the lacunae become confluent and line up. The chondrocytes undergo apoptosis and then secrete alkaline phosphatase and VEGF. This leads to the developement of the periosteal collar and then the formation of the primary ossification centre. There is a massive influx of haemopoetic cells and osteoblasts and clasts. this leads to a breakdown of the the cartillages extracellular matrix and the laying down of boney matrix. Growth continues at the epiphyseal plates after birth, these are the 2nd centres of ossification.
describe the pathophysiology of osteogenesis imperfecta
This is due to a genetic mutation in the genese coding for type one collagen. There is a mutation that results in a change in the primary sequence of amino acids so a conformational change results. There is a number of different types of varying severity with the most extreme cases being death at child birth and the milder ones being more prone to fracture. Symptoms of include increased risk of fracture, poor muscle tone, blue sclera and hearing loss. Overall height can be also be affected.
describe the pathophysiology of osteoporosis
Caused by excessive activity of osteoclasts due to loss of inhibition or over proliferation of. It presents with a decreased bone density. Most commonly it arises in post menopausal women and in old age although there is a number of other risk factors (ethnicity, gender, diet etc)
describe the pathophysiology of osteomalacia/rickets
Deficiency of vitamin D that leads to softening to the bones. This leads to easy fracture, and over curvature of the spine.
describe the pathophysiology of paget’s disease.
Pagets disease is due to the excessive breakdown and rebuilding of bone that can lead to pain and malformation of bone structure. There is a chaotic structure to the relaid bone that lacks the uniformity of healthy bone.
Describe the process of fracture repair in bone.
First a haematoma forms that then leads to swelling around the site of injury. Phagocytes then enter into the haemotoma digesting it and then this becomes granulation tissue. This is highly vascularised. Peripheral granulation tissue becomes hyaline cartilage. Then ossification occurs (a combination of both types) this leads to the formation of cancellous bone which then undergoes remodelling to form the normal uniform ostoid structures
Describe the classification of joints
fibrous (syndesmoses, sutures, gomphoses), cartilagenous (synchondrosis, symphysis), synovial
Describe the standard components of a synovial joint.
capsule, membrance, fluid, articulating cartilage, articulating bone.
what are the 5 common sites for mets in bone cancers
lung, breast, prostate, kidney, thyroid
what are the terms for bowleddedness and knock knees
genu vargus and genu valgus respectively
what are the common bone surface landmarks?
tuberosity/tubercle, spines, trochanter, epi/condyles, facet, crest, sinus, meatus, fossa, foramen, fissure, notch.
what are the 6 types of synovial joints?
hinge, saddle, plane, pivot, condyloid, ball and socket.
what contributes to joint stability?
ligaments, muscle tone, size of articular surface.
Name the tarsals an any major boney landmarks
Talus, calcaneus, cuboid, navicular, cuneiforms 3, 2, 1
What are common traumatic injuries to the bones of the foot?
Calcaneus fracture- hard impact onto heel from a high fall, typically disrupts the talocalneal joint where the talus articulates with the calcaneus.
Describe the superficial and deep lymph drainage of the lower limb and any common pathological changes and indications of these
Superfically they accompany the great/small saphoneus vein, terminating at the superficial inguinal lymph nodes/ popliteal lymph respectively.
Deep lymph drainage is from the popliteal to the deep inguinal which then joins the lumbar thoracic lymph.
If enlarged could be due to micro sepsis or uterine cancer mets.
Which veins are autografted in heart bypass surgery and why?
The great saphoneous vein due to it being muscular.
How do varicose veins occurs? What can they result in?
Damage to to valves in superfical veins result in veins remaining engorged. They result in blood pooling and stasis which can lead to the formation of thrombus and as a result Pulmonary embolism.
What is a saphoneus cut down?
Finding the great saphoneous by cutting down anterior to the medial malleoulus but there is a risk to the saphoneous nerve.
Describe the anterior deep venous network of the lower limb
Formed from the common illiac proximally. this branches into the internal and external common illiac. Then there is an internal branch of the obturator., below which the great saphoneous vein joins in the femoral triangle to the femoral vein. lateral circumflex gives rise to the perforating branch and descending lateral. This communicates with the genvicular veins of the knee. Then the anterior tibial and the dorsal arch
Describe the posterior deep venous network of the lower limb
plantar arch, fibular (with perforating veins) and posterior tibial, popliteal vein and(medial, lateral, superior, inferior), femoral vein and femoral profunda. Also the superior and inferior gluteal.
Describe the anterior-medial superficla venous network of the lower limb
dorsal venous arch, great saphonous then passes anterior of the medial malleolus and then medially of the patella. going up the leg until it drains in the femoral vein.
Describe the posterior superfical venous network of the lower limb
plantar venous network, lateral margin vein of the foot, drains into popliteal vein.
what does DR CUMA stand for?
wrist Drop= radial nerve
ulnar Claw- Ulnar nerve
Ape hand=mediun nerve
What does digit ischaimia from cold/stress suggest?
Primary raynaud’s syndrome.
Describe a common pathology of the tendonous synovial sheath of the fingers and its cause.
Tenosynovitis, from an infected puncture wound.
Describe the symptoms of ulnar claw and describe how it originates.
Cant make a fist or fully straighten hand. This is doe to ulnar nerve injury. Only the 4th and 5th digits affected. due to them being supplied by the medial aspect of the flexor digitorum profundus.
What common upper limb injury can cyclists get?
Handle bar neuropathy. Characterised by medial sensory loss and atrophy of thenar muscles.
What intrinsic hand muscles are innervated by the mediun nerve?
Meat LLOAF: 2 most lateral lumbricals, Oponens pollicis, abductor pollicis brevis, Flexor policis brevis.
Describe the role and location of the interossei
3PAD, 4DAB towards/away the midline respectively. also flex and extend with the lumbricals
What is the role and location of the lumbricals?
operate over the metocarpalpharengeal joint, flex and extend this.1 and 2 are unipenate, and 3 and 4 are bipenate.
Describe the sensory nerve regions on the hand.
ulnar all of 5th and half of 4th digit. This is symetrical on palm and dorsum.
Medium: remainder of palm except most superior region of thumb. finger tops of of medial 2.5 fingers.
Radial: dorsal thumb, medial 2.5 fingers and the hand below them except for the distal region, On palm its the region superior on the thumb (in anatomical position)
Describe the aterial supply to the hand.
3 main supplies from the radius, ulnar and interosseous. Interosseous forms a network merging with both radial and ulnar. Radial and ulnar form a deep and superficial palmar arch with the superficial extending most distaly. The superficial gives rise to the common palmar digits and the deep gives rise to the palmar metacarpal. These both merge to form the proper palmar digital arteries. The ulnar has a dorsal branch as does the radial which forms the dorsal arch which is aided by the presence of perforating arties between the digits..
What is signigicant about the overlap of dermatomes?
Multiple spinal nerves will be innervating one region so a sensory loss will be due to damage to more than one spinal nerve.
Describe the anterior cutaneous nerves from proximal to distal of lower limb.
Genitofemoral, illiguinal, lateral cutaneous, anterior femoral, obturator, lateral sureal, saphoneous, fibular,
Describe posterior cutaenous nerve from proximal to distal of lower limb.
Medial, superficial, inferior clunial, Lateral cutaneous, posterior, saphoneous, medial sureal, lateral sureal, medial calcaneal, medial and lateral plantar.
Describe the arterial supply to the lower limb. from proximal to distal naming branches lateral to medial
Common illiac, external illiac, internal illiac,
External–> femoral, gives off epigastric laterally, branches into lateral and medial circumflex. Femoris profunda and descencing branch of lateral circumflex run paralle to femoral down leg. Profunda gives off perforating arteries posteriorly. Femoral moves behind knee (travelling through adductor hiatus) becoming popliteal artery. Meshwork of genicular arteries anterior to the knee.
Describe the structure of the brachial plexus
has roots from c5–>T1. C5 merges with c6, c7 doesnt merge, c8 and t1 merge. these form the trunks respectively. After the trunks are the divisions. from the inferior is a posterior branch to the middle, from the middle is an anterior branch to the superior. From the superior is a posterior branch to the middle. These then form the cords which are named due to their relative location to the axillery artery. (posterior, medial and lateral). medial gives off 2 branches, one forms the ulnar nerve the other contributes to the mediun nerve along with a branch from the lateral branch. The lateral branch also gives rise to the musculocutaneous nerve. The posterior cord gives rise to the radial artery and the axillery artery.
What are the root values of the terminal branches of the brachial plexus?
radial: c5678, T1
ulnar: C8, T1
Mediun:c6,7,8 t1
Musculocutaneous:c5,6,7
Axillery: c5,6
What key nerves are given off directly from the brachial plexus?
dorsal scapular (c5) long thoracic (c5,6,7), suprascapular (c5,6) subclavian (c5,6), thoracodorsal (c678) medial pectoral, medial cutaneous of arm/forarm (c8,t1), lateral pectoral (c5.6.7)
What can cause an upper brachial plexus injury? what are the symptoms?
rapid force that increases the angle between the neck and shoulder (landing on your head at and angle). Damages the upper roots resulting in likely lesions affecting the axillery and musculotcutaneous and branches off the lateral branch.
What can causes a lower brachial plexus injury? what is its symptoms?
klumpke injury is common by having the arm rapidly abducted to above the head. this damages the inferior roots of the brachial plexus. Would manifest as damage to the ulnar nerve and branches off the medial cord. This would result in ulnar claw most probably but also could manifest as weakness in flexion of shoulder and also loss of innervation in the medial cutaneous region of forearm and arm.
Describe the path of the radial nerve in the upper limb.
Leaves the brachial plexus via the posterior cord and travels down behind the humerus in the radial groove behind the long head of triceps. It then rotates fully and enters the cubital fossa from the lateral side where it is the most lateral of the contents. It then innervates the extensor compartment which originates from the common extensor origin at the lateral epicondyle. It also has cutaneous innervation the hand (predominantly on the dorsal aspect)
Describe the path of the musculocutaenous nerve
from the lateral cord of the brachialplexus, pierces the coracobrachialis, travels deep in the arm passes laterallly to the tendon of biceps brachii where it pierces the deep fascia becoming the lateral cutaneous nerve to the forearm.
What is the path of the mediun nerve?
travels in front of the brachial artery moving medially as it approaches the cubital fossa. Innervates the flexors of the forearm with 2 exceptions.
What is the path of the ulnar nerve?
originates from the medial cord of the brachial plexus, moves distally passing behind the medial epicondyle. Innervates the flexor carpi ulnaris, and the medial half of flexor digitorum profundus.
What should be looked for as indicators of joint injury?
redness, instability, deformity, swelling gait, and systemically a fever, weightloss and raised WBC-count.
What is the trendelunberg sign?
patient stands on one leg, if weak abductors of hip then pelvis will drop. namely gluteus medius and minimus.
What is valgus and varus?
valgus=knocked knees
Varus=bowlegged
How can a joint be imaged?
MRI, CT, US, Xray, arthroscopy
What are the common causes of bone mets?
breast, prostate,lung, kidney, thyroid
How can muscles be catagorised based on their movements?
Agonists, antagonists, synergists and fixators
How is MND diagnosed?
EMG
What are the types of levers used by muscles in the body?
1st- pivot
2nd- force and weight on same side favouring force.
3rd- force and weight on same side favouring weight.
What is the role of skeletal muscle?
Thermogenesis, mobility, posture and balance, joint stability.
What are the different types of skeletal muscle myocyte?
I- slow twitch, red due to many mitochondria
IIa- pink- intermediate
IIb- white with many glycolytic enzymes like the gastronemius and eye muscles.
What is intermittant claudication?
Pain on exertion relieved by rest, the next pain occurs sooner then the first. typically a sign on peripheral vascular disease.
What is compartment syndrome?
Where a leakage into a compartment leads to compression of important structures. I.e in the arm if the brachial artery is perforated and expels blood it will compress the nerves of the arm due to being unable to compress the solid structures of bone and muscle present.
What is the effect of clostridium tetani on motor neurones?
bacterium produce 2 toxins. Tetanospasmin gets into the blood and enters the neurones where it travels up using dyneins via retrograde axonal transport into the CNS where it inhibits gamma amino butaric acid channels stopping the inhibitory input into the neurone. this results in a fused tetany
What is a motor unit?
It is one motor neurone and all the muscle fibres that is innervates and so one impulse results in the contraction of a number of fibres however a motor neurone can innervate anything from 1-1000 mucle fibres depending on the degree of fine motor skills needed.
How does recruitment occur?
By spatial summation. By increasing the number of motor neurones and therfore fibres involved in a particular action. This is done through the use of golgi tendon organs, spindle fibres and joint receptors.
What is muscle tone? How is muscle tone increased? regulated?
Muslces have high levels of elastin.
Muscles can be made to contract harder by temporal summation. This is where the impulse to contract becomes more frequenct increasing the force of contraction from a fasiculation to an unfused tetany to a fused tetany. This is regulated by the feedback to the brain from the proprioreceptors in the muscles which defom due to stress.
What could the possible causes on hypotonia be?
Lesions in any of the nervous pathways.
Motor nerves, sensory afferents, CNS *cerebrellum motor cortex)
Damage/infection in the muscle.
How does being innervated prevent muscle hypertrophy?
Loss of innervation removes cross talk between muscle and nerve which can lead to atrophy of both.
What are the eneregy stores in skeletal muscle?
ATP, creatine phosphate, Glucose–>pyruvate and then pyruvate to lactate or into the link and TCA cycle.
What are the different types of musclular contraction?
Isotonic (concentric, eccentric) , isometric
How does rigor mortis occur?
No ATP after death and so the actin and myosin filaments remain attached and so do not allow for movement (contracture) this leads to a stiffening of muscles in the body.
Describe the flexors of the hip
Sartorius:flex, abducts and laterally rotates thigh when leg is straight, when knee is bent it medially rotates thigh and flexs at knee. (femoral nerve) (iliac spine to tibia)
Pectineus: adducts and flexors hip (femoral nerve) superior pubic rami to pectineal line
Iliopsoas: composed of the 2 below muscles
-psoas major: lumbar rami
-Iliacus:femoral nerve
Psoas minor: lumbar rami
describe the extensors of the knee
Vastas medius: lesser trochanter and medial lip of line of apeara.
Vastas lateralis:greater trochanter and lateral line of apeara
Vastas intermedius: anteriolateral surface of femur
Rectus femoris: anterior infirior illiac spine (also aids in flexing thigh)
All attach to common quadraceps tendon and all by femoral nerve.
Describe the muscles of the gluteal region
Tensa of fascia lata: Superior gluteal, superior anterior illiac crest to lateral condyle of tibia.
Piriformis: anterior of sacrum to greater trochanter
Obturator internus: Nerve of obturator, inferior rami of ischium to greater trochanter.
Maximus: Inferior gluteal, above posterior gluteal line to gluteal tuberosity.
Medius: superior gluteal posterior–>anterior gluteal line to greater trochanter
Minimus: superior gluteal anterior–>inferior gluteal line to greater trochanter
Quadrate fermoris: nerve of quadrate femoris ischial tuberosity to quadrate tubercle
superior gemelli: n. of obturator ishial spine –> greater trochanter
Inferior by nerve to quadrate femoris.
Describe the adductors of the thigh
adductor longus: inferior Pubis–>
adductor brevis: superior pubis–>
adductor magnus: dorsal pubis–>gluteal tuberosity and linea apeara (most lateral)
gracilis: pubis to tibia
obturator externa: lip of obturator foramen–> intertrochanteric fossa.
Pectineus: superior rami of pubis–> pectineal line
All by obturator nerve except the hamstring part of the adductor magnus which is by the sciatic nerve.
Describe the arterial supply to the gluteal region.
Superior and inferior gluteal arteries branch off the internal iliac artery and “flick up” through the greater sciatic notch.
Describe the nervous supply to the gluteal region
both the superior and inferior gluteal nerves branch off the sciatic nerve as it passes through the greater sciatic notch.
What is carpal tunnel syndrome? causes of? symptoms? diagnosis? treament? epidemiology?
compression of the structures in the carpal tunnel. Causes include hypothroidism, pregnancy, obesity, trauma, infection, arthritis, diabetes acromegaly, bleed, tumour. Diagnosis is a combination of factors and symptoms. symptoms include pain, loss of grip strength (atrophy and thenar weakness). Treatment is carpal tunnel release, and treatment of underlying conditions. Most commonly affects white pregnant women also in the age range of 45-60 is a factor outside of pregnancy.
What is contained within the carpal tunnel?
Tendons of the flexor digitorums and flexor policis longus, synovial sheaths covering them. Also the mediun nerve.
What is hilton’s law?
A nerve that passes across a joint also innervates it.
How can the neck of femur be fractured?
Intracapsular: Loss of blood supply leading to necrosis.
Introchanteric fracture: across the trochanters,
What is significant about epiphyseal fractures?
15% of long bone fractures, important to fix quickly, limping gives it away in young children, the shaft moves forwards and upwards in relation to the head. typically caused by acute trauma or repetitive trauma
Describe the hip joint
Acettabulum has triradiate cartiladge which forms the joint cavity.
This is deepened by a fibrocartiladge labrum, the base of the acetabulum is formed by the transverse ligamament, behind which is the acetabulum foramen. The head of femurarticulates with this surface and the fovea capitis allows the joining of the ligament of HOF and a branch of the obturator artery.
The capsule extends over the neck of femur and attaches to the acetabulum and transverse ligament.
The Bursae: Ischialgluteal, trochanteric, iliopsoas.
Ligaments: ILF, PF, ISF
Describe dislocations of the hip
Posterior: requires huge force i.e car accident can cause damage to sciatic nerve, leg is medially rotated.
Describe the osteology of the femur
Anteriorly: fovea of HOF, head of femur, neck of femur, intratrochnateric line, greater and lesser trochanter, adductor tubercle, condyles and epicondyles.
Posterior: interrtrochnateric crest, gluteal tuberosity, pectineal line, quadrate tubercle, spiral line, linea aspera, supraepicondylar lines, intercondylar fossa
Describe the osteology of the fibular and tibia
tibia has anterior line and on the back has the soleal line. It has an intercondylar eminence that articulates with the femur.
Fibular and tibia both has malleloui?
Describe the osteology of the foot
talus calcaneous, cuboid, navicular, cuniforms (1,2,3)
Describe the osteology of the pelvic girdle
illium articulates with the pubis and the ishium in the acetabulum with the triradiate cartiladge and the pubis and the ishium communicate on the obturator foramen. the ishium helps form the greater sciatic notch and also has the ischial tuberosity which is sat on. The illium has anterior-medially the superior and inferior illiac crest and in the centre is the illiac fossa. Posteriorly are the gluteal lines.
what % of total height does the spinal cord make up
42%
What are the roles of the spinal column?
balance (centre of gravity), muscle attachements, boney attachements, protection of the spinal cord, segmented innervation of the body
What movements can the verterbral column undergo?
Flexion, extension, adduction and rotation.
