Locomotor Flashcards
If abducting the shoulder 180 degrees how much of the movement is from which joint?
120 degrees is from glenohumeral joint and 60 from the scapulothoracic joint
What nerve is affected if there is injury to the lattimus dorsi?
Thoracodorsal
What nerve is most at risk in fractures of the medial epicondyle?
Ulna
What sign do you get in ulna injuries?
Claw hand (clawing and flexion of 4th and 5th fingers)
In what nerve injury would you get loss of thenar muscles
median
What is the name of the test for collateral circulation in hand
Allan test
What does a disruption to Shenton’s line show?
NOF
What is the strongest ligament in the hip joint?
The ilio-femoral ligament (anterior)
What does a positive Tredelenburg test show?
Damage to superior gluteal nerve
What are the borders of the femoral triangle?
Inguinal ligament, sartorius, adductor longus
What is the unhappy triad?
PCL, ACL and medial meniscus
What nerve wraps around neck of fibula?
common peroneal
What does the common peroneal innervate and what do you get if its damaged?
Muscles of anterior and lateral compartment of the leg = foot drop.
And sensory to the dorsum of the foot
What nerve passes through the tarsal tunnel?
Tibial nerve
What type of collagen is bone?
Type 1
What is a romosozumab?osteoporosis
A monoclonal antibody inhibiting sclerostin (treats osteoporosis)
How do osteoclasts absorb bone?
They acidify a matrix area and the hydroxyapatite dissolves setting free Calcium
What do osteoblasts fill lacuna with?
Osteoid
How does calcitonin regulate calcium?
It lowers plasma ca2+ by directly inhibiting osteoclast activity, increasing excretion from kideny and inhibiting absorption from intestines
how does Cinacalcet work for secondary hyperparathyroidism?
It binds to allosteric site of calcium sensing receptor of parathyroid which increases the sensitivity of the receptor to calcium. Therefore reduces PTH
What does calcitrol do?
It is the active form of vit D and binds to Vit D receptor and induces genes necessary to maintain calcium reserves. It mainly increases uptake of calcium from intestines
What hormone counters PTH affect on vit D?
Fibroblast growth factor 23
When and where is FGF23 secreted?
By osteocytes and osteoblasts in response to increased calcitrol and dietary phopshate
A mutation in what gene causes x linked hypophosphatemia?
PHEX gene (causes rickets/osteomalacia)
What hormone does Growth Hormone stimulate release of?
IGF-1
What does IGF1 do to chondrocytes
Stimulates chondrocytes in epiphyseal plate to divide
What effect does oestrogen have on bone?
It directly stimulates bone formation and reduces the number and activity of osteoclasts
What is tendinosis?
Chronic injury of a tendon
For tendon healing, when is passive motion beneficial as opposed to cast immobilisation?
Beneficial for flexor tendon healing, detrimental for tendon to bone healing
What connecting fibres do you find in fibrous enthesis?
Sharpey fibers
When are fibrocartilage enthesis better than that fibrous enthesis?
In joints where theres going to be angle changes
What HLA is enthesitis associated with?
HLA B27
What co-morbid conditions are associated with enthesitis?
inflammatory bowel disease, psoriatic arthritis, ankylosing spondylitis
What’s the difference between enthesophytes and osteophytes?
Enthesophytes originate from insertion of ligament and tendons
Osteophytes originate from border of articular cartilage
What could be used for severe autoimmune enthesitis?
Anti TNF therapy
What is a treatment for De Quervian’s?
Shave down the radial styloid as it is caused by tendon sheath rubbing over styloid
What is an undifferentiated connective tissue disease?
Systematic Lupus Erythematosus
What type of hypersensitivity is lupus?
Type 3 - anti nuclear antigens against intra-nuclear proteins
What treatment inhibits B cell activating factor and is a treatment for SLE?
Belimumab
How does rituximab work for SLE?
It is a CD20 blocker (suppresses B cells)
Difference between a T score and a Z score?
T score = number of standard dev of the mean health 30 year old of same age
Z score = number of standard devs from someone of same age, gender and ethnicity
What type of bone is most affected by osteoporosis?
Trabecular bone eg vertebral bodies and femoral neck
How can teriparatide treat osteoporosis?
It is a portion of PTH. Intermittent PTH activates osteoblasts more than osteoclasts (once daily injections)
What are some complications of bisphosphonates?
Osteonecrosis of the jaw, atypical fractures eg subtrochanteric and femoral shaft fractures
How does romosozumab work for osteoporosis?
It is an antibody against sclerostin which leads to increased osteoblast activity
What would you find in lab results for osteomalacia (rickets)?
Low serum calcium and phosphate
High alkaline phosphotase
What is a characteristic finding of osteomalacia on xray?
Looser zones - pseudo fractures (areas of unmineralised bone)
What can you label bone with to check for mineralisation?
Tetracycline
What type of cartilage is the meniscus?
Fibrocartilage
What is the tide mark?
The line in which the cartilage changes from calcified to uncalcified
Articular cartilage is mainly type II collagen, but what is the other main type of collagen present particularly in the deep layers?
Collagen type X
A loss of expression of what can cause osteoarthritis?
HMGB2 = high mobility group protein 2 which is normally prominent in superficial zone and supports chondrocyte survival
Loss of what causes water to move in an out of the joint faster and leads to osteoarthritis
Proteoglycans
What are type A and type B synoviocytes?
Type A = bone mArrow derived macrophages
Type B = fibroBlast like connective tissue
How long would a normal string of synovial fluid be?
4-6cm
What is a key interleukin in RA that induces more osteoclasts, sensitises noiceptors and attracts neutrophils?
IL8
What CD4+ cells infiltrate in RA and what do they secrete?
Th17 and they secrete IL-17
What are the most numerous cells in synovial effusion in RA
neutrophils
What does seropostive RA mean?
They are ACPA positive
What are the strongest risk alleles for seropositive RA?
HLA-DRB1
PTPN22
What interleukins and cytokines are produced by macrophages and leak into blood stream in RA?
IL-1 and IL-6 and TNF alpha. TNF alpha important to remember
What type of anemia does RA usually cause?
Normochromic, normocytic anemia but can progress to hypochromic
What does citrullination mean?
It is when arginine is converted into citrulline and then the immune system might not recognise them as self antigens
What type of Ig is rheumatoid factor?
IgM antibody that targets the Fc domain of altered IgG
What does anti-CCP target?
Citrullinated proteins
What protein can cause scelrostin to be released which inhibits osteoblast differentiation?
DKK-1
What antibodies are associated with severe, erosive RA despite treatment with TNF inhibitors?
PAD4
What is carbamylation?
Conversion of lysine into homocitrullines by chemical reaction with cyanate
How can smoking lead to RA?
It increases the levels of cyanate and so increases amount of carbamylation
What does a histological section of a classic infantile myopathic hypotonia look like?
The type 1 slow fibres (paler) are a lot smaller
(the other way around for non classic)
What might you see on biopsy for the myositis?
Variation in fibre size, central nuclei, necrosis and regeneration and infiltrate of lymphocytes (CD8 cytotoxic T cells)
What is the most common ANA in myositis that gives a worse outcome?
Anti-Jo1
What muscles are affected more in inclusion body myositis?
Finger and wrist flexors
Knee extensors (loss of quadricep reflex)
What is inheritance pattern of Duchenne and Becker muscular dystrophy?
X-linked recessive
How many points on the ACR/EULAR score do you need for an RA diagnosis?
6 or more out of 10
What are the standard treatment concepts for mild, moderate and severe RA?
Mild - methotrexate + second line DMARD
Moderate -methotrexate and TNF alpha inhibitor
Severe - methotrexate + rituximab
How does methotrexate work?
It is a folic acid antagonist- limiting RNA and DNA synthesis and it is an anti-cytokine inhibiting production of IL1 and NF-kB
What is sulfasalazine a combination of?
Sulfapyridine and 5-amino salicyclic acid. (5-ASA stays in the gut)
What RA drug also treats ulcerative collitis?
Sulfasalazine
How does hydroxychloroquine work?
It increases the lysosomal pH in antigen presenting cells and blocks TLR9
What pro drug efficacy is similar to methotrexate?
Leflunomide
How does leflunomide work?
Inhibits pyrimidine biosynthesis
Name some TNFalpha blockers
Infliximab - monoclonal antibody against TNFalpha
Etanercept- binds to TNFalpha and stops signal transduction
Adalimub -monoclonal antibody
How do you measure the Q angle?
Draw a line from ASIS to centre of patella
Draw a line from tibial tuberosity to patella.
Normal Q angle = 15-20 degrees
What are the nodes that grow on the distal interphalangeal joint in OA?
Herberden’s node
What are the nodes that grow on the proximal interphalangeal joint in OA?
Bouchard’s node
What spinal joint is most often damaged in RA?
Atlanto-axial (misalignment of 1st and 2nd vertebrae). You get subluxation
What infections can go on to result in reactive arthritis?
Urethritis / cervicitis /infectious diarrhea
What can sausage toe be a sign of?
Reactive arthritis
What prostaglandin inhibits gastric secretion?
PGE2
What kind of drug is diclofenac?
Preferential COX-2 inhibitor
What is an example of an irreversible non selective NSAID?
Aspirin
What is basement membrane composed of?
Laminin 332, collage IV, collagen VII
What type of collagen is papillary dermis?
Type III collagen
What type of collagen is reticular dermis?
Type I
What are the two types of hair follicles?
Vellus - body hair, Terminal - scalp and secondary sexual hair
What are the three main phases of hair cycle?
Anagen -active
Catagen - regressive
Telogen -resting
What hip replacement material has least wear and tear?
Ceramic on ceramic
What muscles are often used for free muscle transfer?
Gracilis muscle and rectus femoris
What does a Colles fracture refer to?
Dorsal displacement of distal fragment of radius - dinner fork look. Think fallen with wrist extended
What is a torus fracture?
A buckle fracture, happens in kids, axial loading causes trabecular compression on one side
In bone healing, how long does fibrocartilaginous callus last?
About 3 weeks
What are the cells involved in fibrocartilaginous callus formation?
Fibroblasts and osteogenic cells invade procallus and make collagen
Chondroblasts begin to produce fibrocartilage
How long does the bony callus last?
from week 3 to about 3-4 months (woven bone)
What is neurotmesis?
Complete transection of a peripheral nerve
What is a common bacteria that can cause septic arthritis in children?
Haemophilus influenza
What is talipes equinovarus?
Club foot - fixed varus and equinus deformity
What are associated with club foot?
Breech, connective tissue disorders eg Ehlers Danlos, oligohydramnios, genetic syndromes
What is the Ponseti method?
Use of multiple manipulative casts to correct club foot
What is Perthes disease?
Avascular necrosis of femoral head (normally self limiting)
What does SUFE stand for?
Slipped upper femoral epiphysis
(more common in boys and in the left hip)
What type of fracture is a SUFE?
Salter Harris type 1
How do you detect SUFE on XRAY?
No femoral head above Klein’s line
What is Blount’s disease?
A growth problem of medial part of proximal tibia, causes tibial varus (knees bow outwards)
What risk factors are associated with Blount’s disease?
Obesity and walking early
What is sever’s disease
Calcaneal apophysis
What causes Kohler’s disease?
Avascular necrosis to navicular bone often associated with infection
What causes Kienbock disease?
Interruption of blood supply to the lunate, cause not known.
maybe think KienBOCK like BOX, think Boxing to remember its in the hand
What crystals get deposited in gout?
Monosodium urate crystals
What is podagra?
Inflammation of 1st MTP joint (big toe)
Eating a diet high in what substance can lead to gout?
Purine
What cells would you see in the synovial fluid in gout?
Polymorphonuclear neutrophils (PMNS), would have a high WBC too
How does colchicine work for gout?
It stops microtubule polymerisation hence stopping neutrophils
What’s the MAO of Allopurinal?
It inhibits xanthine oxidase hence reducing generation of uric acid
What is pseudogout?
It is the deposition of calcium pyrophosphate, you often get it in OA
What are the spinal changes in osteoporosis kyphosis?
Increased thoracic curvature (kyphosis) and then a compensatory increase in cervical lordosis
What is Sheuermann’s disease?
A disease of adolescence (epiphyseal growth plates of vertebral bodies) that causes hyper kyphosis
What muscle dysfunction is associated with excessive lumbar lordosis
Shortened Psoas muscle
How great a curve in scoliosis before you do surgery?
50 degrees
What are the most common levels for herniated disc?
L4/L5, L5/S1
What does DISH stand for?
Diffuse idiopathic skeletal hyperostosis (ossification of anterior longitudinal ligament, looks like candle wax dripping)
What radiographic signs do you get on MRI of ankylosing spondylitis?
Dagger sign and bamboo shoot spine
If impetigo is just in one place how should you treat it?
1% hydrogen peroxide cream
What is the pathophysiology behind scalded skin syndrome?
Exotoxins to staph aureus are produced which destroy the desmosomes holding together keratinocytes so you get detachment of epidermal cells
What does molluscum contagiosum cause?
water warts
What is pityriasis versicolour an example of?
Yeast infection
What are permethrin, ivermectin and crotamiton examples of?
Anti parasite medications, used to treat scabies
What bacteria is spread by ticks causing Lyme disease?
Borrelia
What causes lupus vulgaris?
TB infection
What causes Leishmaniasis?
Sandflies
What does type 1 hypersensitivity refer to?
IgE mediated hypersensitvity. IgE bound to mast cells, when allergen binds causes degranulation
What is type 2 hypersensitivity?
IgG mediated cytotoxic hypersenstivity eg blood transfusion RBCs destroyed
What is type 3 hypersensitivity?
Immune complex mediated, eg antigen-antibody complexes desposited in tissues causing activation of complement
eg RA, systemic lupus erythematosus
What is type 4 hypersensitivity?
Cell mediated hypersensitivity. Th1 cells secreting cytokines etc eg contact dermatitis, tuberculin reaction, MS
What type of hypersensitivity is uticaria (hives)?
Type 1
What common allergens do dust mites release?
Der P1
What is a new biological treatment for urticaria and asthma (IgE mediated)?
Omalizumab (binds to IgE decreasing cell bound IgE)
What antibodies cause pemphigus vulgaris? (blisters on mucus membranes)
antibodies to desmoglein 3 (an epidermal desmosomal adhesion protein)
What are new treatments for alopecia and vitiligo?
JAK inhibitors - Ruxolitinib
What cell is the link between adaptive and innate immunity?
APCs
What do hybrid hip replacements involve?
The use of a cemented femoral stem with an uncemented acetabular cup
In what injury do you get loss of rounded profile?
anterior dislocation
(normally from deltoid muscle)
What nerve is damaged in winging of the scapula?
long thoracic
What are the signs of deltoid paralysis?
loss of roundness of shoulder, numbness over regimental badge and weakness in abduction
What palsy do you see shoulder falling?
trapezius palsy (spinal accessory)
What do radius and ulna articulate with in the hand?
radius articulates with scaphoid and lunate
ulna doesnt articulate with any carpals (fibrocartilage fills the gap)
What nerve passes through the carpal tunnel?
median nerve
What artery runs through ligamentum teres?
obturator
What nerve palsy would result in paralysis of plantar flexors and sensory loss back of leg and sole of foot?
tibial nerve palsy
Nerve roots of femoral nerve?
L2, L3, L4
What nerve provides sensation to the skin between big and second toe?
deep peroneal nerve
What is the inorganic part of bone?
Calcium hydroxyapatite
Where is preferred for bone marrow transplantation?
iliac crest
What cells sense mechanical strain on the bone?
osteocytes
What is sclerostin secreted by and what inhibits its secretion?
produced by osteocytes
inhibited by PTH, and mechanical strain
What regulates elimination of phosphate via kidneys?
Fibroblast growth factor 23
What essentially has the opposite effect to PTH?
Calcitonin
Where does the final step of hydroxylation of vit D to active form take place?
Proximal tubule via 1-alpha hydroxylase
What is the central target organ of calcitrol/ activated vit d?
Duodenum
How can chronic kidney disease have affect on bones?
Increased FGF23 and decreased calcitrol, leads to increased PTH and therefore bone disorder
What is FSH effect on bone?
stimulates osteoclast activity but is compensated by actions of oestrogen
What are centrally located nuclei a sign of?
muscle repair
What can be given prophylactically to prevent heterotopic ossification?
NSAIDs (inhibit COX2)
How would you control loading for ruptured achilles?
Cast immobilisation, as it is tendon to bone
When does intrinsic tendon healing occur?
In any tendon that is covered by a tendon sheath
What essentially is ankylosing spondylitis?
Enthesitis of IV disc and anterior longitudinal ligament
What is a surgical treatment for trigger finger?
cut the annular ligament
What are more than 95% patients with SLE positive for?
ANA - anti-nuclear antigens
What is raloxifene? (used for osteoporosis)
it is a selective oestrogen receptor modulator (estrogenic effects on bone)
During which part of ovulatory cycle does bone resorption decrease?
Decreases during luteal phase bc of high progesterone
How does denosumab work for osteoporosis?
It is a monoclonal antibody to RANK L
(RANKL is what binds to RANK receptor on osteoclasts)
What do you see on osteomalacia bone biopsies?
wide seams of unmineralised osteoid
What type of collagen is the ECM of cartilage?
II, IX, X and XI
How do collagen fibre orientations change as you move down the articular layers?
superficial - parallel, highest tensile strength
intermediate - criss-crossed oblique allows compression
deep zone - perpendicular
What is presence in cartilage and can hold up to 50x their dry weight in water?
proteogylacans
What is synovial fluid?
The ultrafiltrate of blood with added hyaluronic acid
What is added to synovial fluid in mucin clot test?
2-5% acetic acid
What is produced by osteoclasts that leads to more osteoclasts, attracts neutrophils and sensitises nociceptors increasing pain?
IL8
Which autoantibodies do not seem to play a major pathogenic role in RA?
Rheumatoid factor autoantibodies
What is polymyositis and dermatomyositis?
They are inflammatory myopathies, autoimmune and associated with microbial infection
When in dermatomyositis or polymyositis would you need long term immunosuppression?
If there are anti Jo-1 antibodies
What do you see on a biopsy for inclusion body myositis?
fibres contain empty vacuoles and clumps of cellular material that contain amyloid like material ( congo red)
What is Duchenne’s a problem of?
Dystrophin (responsible for connecting cytoskeleton of muscle fibre to basal lamina)
Which muscle fibres get more affected by corticosteroids and statins?
type 2
Foods rich in this could help improve osteoarthritis symptoms?
Omega-3 (oily fish)
What is used in mosaicplasty?
undamaged cartilage from less weight bearing regions
What are future options for biological treatments for OA?
IL-1 blockage, TNF inhibition
What do you need to check at least every three months in methotrexate patients?
complete blood count and liver function tests
What drugs aren’t really used much anymore for RA?
D-pencillamine and gold salts
Anakinra, canakinumab and rilonacept all work on what?
IL-1 (for gout)
What is the first oral biological option?
JAK inhibitors (tofacitinib, barcitinib and upadacitinb)
When might you see gull-wing or saw-tooth appearance?
In erosive OA, post-menopausal women more affected
What effects can NSAIDs have on kidney?
They can leads to Na and water retention = hypertension and kidney injury
Where is the only place that both COX1 and COX2 are found under resting conditions?
CNS
What links keratin cytoskeleton to basement membrane?
Hemidesmosomes
What is the most abundant cell in the dermis?
fibroblast
Which layer of skin contains many blood vessels?
Papillary layer (directly below epidermis and BM)
What antibody activates osteoclast in RA?
ACPA causes monocytes to differentiate
What does reverse hybrid hip replacement mean?
That the cemented version is the bit in the acetabulum and not in femur
What tendons are often used for ACL?
semitendinosous or gracilis tendon
Neck of fibula fractures what nerve is at risk?
common peroneal
What are you looking for on xrays of stress fractures and why?
Periosteal lifting as they are fractures of the trabeculae network within the bone
What are the stages of bone healing?
1) fracture haematoma
2) fibrocartilaginous callus
3) soft callus
4) bony callus lasts about 3-4 months
5) bone remodelling
In pelvic fractures where is the majority of the haemorrhage coming from?
posterior venous plexus
What is a complication of fractures that can lead to deterioration in consciousness and petchiae rash?
Fat embolism - fat getting into blood stream
What is normal compartment pressure and at what pressure would it be an emergency?
normal = 0-10
emergency = 30 plus
What is the most common organism causing septic arthritis?
staphylococcus aureus
What is a common lab finding in septic arthritis particularly in children?
neutrophilia
What is i can’t see, can’t pee, can’t climb a tree about?
reactive arthritis bc it affects eye, urinary system and hands and feet
What is the name for necrotic bone?
sequestrum
What can be used to treat gram pos osteomyelitis?
flucloxacilin
How do you test for congenital hip dysplasia?
Barlow test - adduct and push downwards
Ortolani - abduct and push forwards with fingers
Galeazzi sign - leg length discrepency
complications of congenital hip dysplasia?
Avascular necrosis and femoral nerve palsies
What are the four stages of Perthes?
1) necrosis - up to one year
2) fragmentation - dead cells absorbed and replaced, variable femoral head shapes
3) reossification - femoral head continues to grow
4) remodelling - continues
What age does Perthes frequently occur?
between 4-8 years
What are the steps to a gout attack?
proteins lower Ph making more crystals form
white blood cells attack
crystals pop the cell
cell releases proteins
proteins call in more white blood cells
What is inside the tophi in gout?
urate crystals surrounded by lymphocytes, macrophages and foreign body cells
How high does serum uric acid need to be before it should definitely be treated?
11mg/dL
What biologicals can be used for gout?
IL1 biologicals - rilonacept, canakinumba, anakinra
How does probenecid work for gout?
It increases uric acid excretion
How does rasburicase work for gout?
it catalyses the conversion of uric acid to allantoin
What can acute pseudogout be triggered by?
trauma, rapid reduction of serum calcium
What direction would gout and pseudogout crystals face?
gout - yellow diagonally up, blue diagnonally down
pseudo-gout - other way around
What crystals might you find in a rare case of RA?
cholestrol crystals / lipid spherules
What is a treatment for osteoporosis kyphosis?
kyphoplasty - inserting and inflating balloon into bone to make it less wedge shaped
What are Schmorl’s nodes?
They are herniated discs bulging upwards or downwards - common in Sheuermann’s disease
How do you treat Sheuermann’s disease?
physio - increase strength of paraspinals
bracing - if less than 65 degree angle
surgical if greater than 65 degrees
What type of collagen is annulus fibrosus?
type 1
What bacteria tend to cause folliculitis (carbuncles, boils)
stayphyloccous aureus
Difference between cellulitis and erysipelas?
cellulitis - infection in subcut tissuess
erysipelas - superficial cellulitis (infection just in dermis and not the sub cut fat)
what is Scrofuloderma?
tuberculous involvement of skin from TB infection in underlying lymph nodes
What causes leprosy?
mycobacterium leprae or mycobacterium leptomatosis
What is the treatment for leprosy?
rifampicin, dapsone and clofazimine
How do you treat pemphigus vulgaris?
immunosuppression with c mycophenolate motefil or azathioprine
rituximab - targeting CD20 on b cells
What are five types of salter harris fracture
S - straight across type 1
A - Above type 2
L - lower type 3
T - two or through type 4
ER - erasure type 4
What kind of injury will lead to hand of benediction when asked to make a fist?
a high median injury (common in supracondylar fractures of humerus). results from paralysis of flexor digitorum superficialis, and pollicis longus
