LOCO Revision5 Flashcards
Which would commonly present with a fracture from a low force injury?
RA
OA
OP
Gout
OP
Osteoporosis patients are likely to present with
lordosis
kyphosis
scoliosis
kyphosis: called
Osteonecrosis is associated with the treatment of
RA
OA
OP
Gout
OP
Recombinant PTH used to treat OP is called? [1]
Teriparatide
Name drug A used to treat osteoporosis [1]
Denosumab
Name drug A used to treat osteoporosis [1]
Teriparatide
alkaline phosphatase (ALP) is produced by which cell type? [1]
Osteoblast
Which disease is shown in this CT [1]
Describe the pattern shown in the skull [1]
Pagets disease; cotton wool skull
Osteoporosis
What is T and Z score on a DEXA scan? [2]
Which is more commonly used? [1]
T-score = number of standard deviations from the mean young (30 yr) same gender and ethnicity. More commonly used
Z-score = number of standard deviations from same age, gender and ethnicity. Used for younger populations
Which 3 locations do you measure a T score from in the body? [3]
Why do you measure these areas? [1]
Neck of femur, lumbar vert or distal radius
Have high areaa trabecular bone here [1]
What T score is a clinical cut off that suggests osteoporosis? [1]
What T score is a clinical cut off that suggests osteopenia?
Osteoporosis: T-score lower than -2.5. [1]
Osteopenia: T-score between –1.0 and –2.5 standard deviations below normal.
How would a patient present with osteoporosis? [1]
Have a fracture due to low force injury
Name two bones that are more likely to suffer from osteoporosis [2]
Vertebral bodies
Femoral neck
Describe pathophysiology of osteoporosis [3]
- Bone formation is normal
- Just relative increase in bone resorption not matched by formation
- Trabecular bone more at risk
Trabecular bone almost dissapeared on R (L is normal)
Describe the clinical presentation of osteoporosis [3]
- Fracture is the only cause of symptoms in osteoporosis
- Sudden onset of severe pain in the spine, often radiating to the front
- Thoracic vertebral fractures may lead to kyphosis - ‘widows stoop’
What is first line treatment for osteoporosis? [1]
Describe MoA [3]
Bisphosphonates:
- inhibits osteoclast activity
- promotes osteoclast apoptosis
- Decreases RANKL expression (so osteoblasts don’t turn into osteoclasts [?])
Describe complications of bisphosphonates
Kills off osteoclasts: don’t remove old bone: thickened bone
Get giant osteoclasts: poisoned osteoclasts
Osteonecrosis occurs
Osteoporosis treatment
Describe the MoA of Teriparatide [2]
Teriparatide is a recombinant PTH:
- PTH upregulates RANKL - signals osteoblast to differentiate when have low Ca2+: work indirectly on osteoclasts to boost bone making potential
- Intermittent exposure to PTH activates osteoblasts more than osteoclasts
Osteoporosis treatment
Describe the MoA of Denosumab [2]
PTH normally inhibits OPG.
Denosumab is a an osteoprotegrin artificial antibody & acts as a monoclonal antibody to RANK:
Denosumab: human monoclonal antibody that inhibits RANKL and helps regulate turnover in healthy bone. Denosumab binds with high specificity and affinity to the cytokine RANKL, inhibiting its action; as a result, osteoclast recruitment, maturation and action are inhibited, and bone resorption slows
Descibe pathophysiology of Pagets disease [2]
Describe the three phases of Pagets disease [3]
(Theory) osteoclasts: may be infected with a virus that alters them AND genetics
Phases:
1. increased rate of bone resorption:
* large number of giant osteoclasts
2. Compensatory phase / proliferative:
* increased bone formation & accelerated depostion in disorganised manner
3. Burnt out phase: sclerotic:
* Hyper-vascular bone marrow; Bone hypercellularity may diminish leaving dense “Pagetic bone”
How do serum results for Ca, PO4, ALP, PTH and 1,25(OH)D2 present for osteoporosis? [1]
Normal
How do serum results for Ca, PO4, ALP, PTH and 1,25(OH)D2 present for osteomalacia? [1]
Explain each result
Low Ca
Low PO4
ALP high
PTH high
Vit D low
- Main cause of osteomalacia: low vitamin d
- Low PO4 and Ca due to phosphate being excreted in order to keep any calcium possible via renal regulation).
- ALP high because produced in osteoblasts
- PTH high due to low Ca2+
How do serum results for Ca, PO4, ALP, PTH and 1,25(OH)D2 present for Pagets disease? [5]
Explain your answer [1]
Ca: normal
PO4: normal
ALP: raised
PTH normal
Vit D: normal
ALP raised due to characterised by high burn turnover
How do serum results for Ca, PO4, ALP, PTH and 1,25(OH)D2 present for renal failure [5]
Explain your answer [1]
failure leads to vitamin D deficiency, as 1,25(OH)2 D3 is made in the kidney.
This results in high PO4, low calcium and normal/high alkaline phosphatase
Name a rare complication of Paget’s disease that occurs in 1% of cases [1]
Osteosarcoma
What would lab results of a patient with osteomalacia show:
- Ca2+ levels [1]
- PO4- levels [1]
- ALP levels [1]
- Vitamin D levels [1]
- Reduced serum calcium and phosphorous
- High alkaline phosphatase (as this is a product of osteoblasts, so there is increase compensatory osteoblastic activity)
- Low vitamin D levels
Describe the pathophysiology of osteomalacia [2]
Osteomalacia is a condition that is the result of insufficient calcium and phosphate to mineralise new bone osteoid.
This results in bones becoming softer and more liable to bend or fracture
. It is usually result of vitamin D deficiency either in diet or production, and has different clinical presentation in adults and kids:
How would you diagnose osteomalacia from a bone biopsy? [1]
Normal bone:
- approx. 20% unmineralized bone osteoid
Osteomalacia:
- wide seams of unmineralized osteoid. In severe cases, up to 100% of the bone is covered by unmineralised osteoid.
Which drug would allow you to determine the level of bone mineralisation [1]
Tetracycline chelates: less labelling would be seen
What phase of Pagets Disease is depicted? [1]
Explain your answer [1]
Burnt-out sclerotic phase of Paget disease (Phase 3):
Woven bone appears as bony shelves divided by cement lines into irregular regions.
What are the arrows pointng to in this slide from a Pagets disease patient? [1]
Cement lines
Which pathology is depicted in this X-ray
Osteoporosis
Osteomalacia
Pagets Disease
Osteoarthiritis
Osteosarcoma
Which pathology is depicted in this X-ray
Osteoporosis
Osteomalacia
Pagets Disease
Osteoarthiritis
Osteosarcoma
How would you confirm Osteosarcoma from a biopsy? [1
Giant cells confirm the diagnosis of an osteosarcoma arising out of Paget’s disease.
Osteosarcoma arises as a complication from:
Osteoporosis
Osteomalacia
Pagets Disease
Osteoarthiritis
Osteosarcoma arises as a complication from:
Osteoporosis
Osteomalacia
Pagets Disease
Osteoarthiritis
How do you treat Pagets disease? [5]
- Bisphosphonates work directly on osteoclasts to slow bone resorption. Can be given orally for 2-6 months, or IV single infusion-3 infusions. Bisphosphonates can almost cure Paget’s disease if you catch it early, and stop the osteoclast hyperactivity, as this will prevent sclerotic bone from forming.
- Calcium and vitamin D supplements
- Pain management
- Surgery
- Calcitonin used to be used more often, but now less than bisphosphonates
What is sclerostosis caused by? [1]
How do patients with sclerotosis present? [2] Explain your answer [1]
Absence, abnormal or reduced produced of sclerostin
Sclerostin produced by healthy osteocytes and inhibtis osteoblasts to prevent XS bone formation
Condition results in resistance to fractures and XS height
Which nerve is at risk here? [1]
median
Ptx has normal serum calcium, phosphate, ALP & PTH. Which condition are they most likely to have?
Paget’s disease
Chronic kidney disease
Primary hyperparathyroidism
Osteoporosis
Osteomalacia
Osteoporosis
Damage occurs from twisting injuries:
Posterior cruciate ligament injury
Menisical injury
Medial collateral ligament injury
Lateral collateral ligament injury
Menisical injury
A female immigrant from the Indian subcontinent presents with ‘bone pain’, muscle weakness and anorexia. Bloods show a decreased calcium and phosphate level is a stereotypical history of ? [1]
Osteomalacia
A patient is found to have the following results: low serum calcium, low serum phosphate, raised ALP and raised PTH. Which condition are these findings most consistent with?
Paget’s disease
Chronic kidney disease
Primary hyperparathyroidism
Osteoporosis
Osteomalacia
Osteomalacia
Which of the following commonly affects the DIP and PIP joints?
Paget’s disease
Osteoathritis
Osteoporosis
Osteomalacia
Rheumatoid arthritis
Osteoathritis
Which of the following commonly affects the MCP and PIP joints?
Paget’s disease
Osteoathritis
Osteoporosis
Osteomalacia
Rheumatoid arthritis
Rheumatoid arthritis
X-ray findings include osteophytes forming at joint margins
Paget’s disease
Osteoathritis
Osteoporosis
Osteomalacia
Rheumatoid arthritis
Osteoathritis
Which of the following antibodies is most associated with RA?
P-ANCA
Anti-dsDNA
Anti-Ro
Anti ACPA
Anti La
Anti ACPA
SLE
SLE
An elderly man is investigated for ‘bone pains’. He is known to be deaf. Bloods show a raised ALP and a skull x-ray shows a thickened vault is a stereotypical history of? [1]
Paget’s disease
Colchicine - inhibits microtubule polymerization by binding to tubulin, interfering with mitosis. Also inhibits neutrophil motility and activity
STI –> arthritis, urethritis, conjunctivitis in a question is most likely to indicate ? [1]
Reactive arthritis
State three categories of inflammatory joint disease [3]
- Infection: septic arthiritis or generalised arthralgia
- crystal arthropathy: gout and pseudogout
- Autoimmune disorders: RA, spondarthritis, connective tissue disease
Many joints / polyarthralgia would be suggestive of what type of disease? [1]
Single joint / monarthralgia would be suggestive of what type of disease? [1]
polyarthralgia: autoimmune disorders
monarthralgia: inflammatory disorder
Draw a flow chart for diagnosis of joint pain
Describe the features of RA [3]
Symmetrical
Hands and feet in 80% of cases
Early morning stiffness
Valgus deformity
Bakers cyst: synovial fluid at popliteal area
What is this sign of RA [1]
Bakers cyst: synovial fluid at popliteal area
State three eye complications of RA [3]
Why is the eye commonly a problem? [1]
RA effects type 2 collagen; get lots of type 2 collagen in they eye
Keratoconjunctivitis sicca
Scleritis & episcleritis
Scleromalacia perforans: intraocular contents prolaspes out of the sclera
Describe three neuromuscular complications of RA [3]
Muscle wasting
Carpal tunnel syndrome
Atlanto-axial subluxation: odointal peg impinges on the spinal cord
What causes cervical myelopathy in RA patients? [1]
What are signs of cervical myelopathy? [5]
Compression of the spinal cord and brain stem is typically caused by atlantoaxial instability (AAI) or atlantoaxial subluxation (AAS)
spasticity (sustained muscle contractions)
hyperreflexia
pathologic reflexes
digit/hand clumsiness
gait disturbance
State a cardiac [1] and bone [1] complication of RA
ischaemic heart disease
osteoporosis
State three connective tissue diseases
Systemic lupus erythematosus:
Scleroderma / Systemic sclerosis: progressive atrophy of soft tissue
Dermatomyositis: high level of creatine kinase; muscle weakness - get lots of rashes. proximal weakness
Describe pathophysiology of Systemic lupus erythematosus
Characterised by anti nuclear antibodies (antibodies to proteins within the persons own nucleus): causes immune system to target these proteins and generates inflammatory response / loss of tolerance
Inflammation leads to the symptoms
Describe the symptoms of SLE
90% of patients have arthritis:
* symmetrical small joint polyarticular arthiritis (most common)
* jaccoud arthropathy (rare)
* avascular necrosis
Fatigue
Weight loss
arthralgia
myalgia
fever
butterfly rash: gets worse with sunlight
shortness of breath
hair loss
