Bones and Joints Flashcards
Describe the difference between cortical and cancellous bone
Cortical = compact bone, layers of concentric rings (osteons)
Cancellous = Spongy bone, interconnecting layers of rods and plates
what is the main protein that forms in lamellae
Type 1 collagen
Osteoblasts ____, osteoclasts ____
Osteoblasts synthesize bone, osteoclasts resorb bone
How does the parathyroid hormone influence bone?
Stimulates osteoclasts to resorb bone to increased serum calcium levels
How does Vitamin D influence bone?
synthesized in the skin and taken in from diet, Vit D promotes calcium absorption
What is calcitonin and what does it do?
Enzyme that acts as opposite to PTH, lowers blood calcium levels by promoting calcium deposition into bones
What are the stages of bone healing?
Cellular stage, vascular stage, primary callus, bony callus, mature callus
(Haematoma, granulation tissue, bony resorption, proliferation, reorganisation)
What is the cause of osteogenesis imperfecta?
Rare, autosomal dominant genetic condition
What does osteogenesis cause?
collagen defect that causes brittle bones
4 types that vary in severity (1 least severe, 2 kills you)
Symptoms of osteogenesis imperfecta?
Blue sclera
deafness
bruising easily
can have cardiac complications
What are some dental considerations of osteogenesis imperfecta?
XLA caution > massive fracture risk
GA risk > normally have cardiac issues
What is cleidocranial dysplasia
Rare, autosomal dominant genetic condition
What are the symptoms of cleidocranial dysplasia
absent or defective clavicle
broad, short skull
hypoplastic midface
What are dental considerations of cleidocranial dysplasia?
- can cause mandibular protrusion CIII occlusion
- can cause clefts, hypodontia, supernumeraries
- abnormal root morphology
What is another name for Albers-Schonberg Disease?
Osteopetrosis
What does osteopetrosis cause?
Autosomal dominant condition
Causes defective osteoclasts, excessive bone density (opposite to osteoporosis)
What causes Rickets? (osteomalacia)
Lack of Vitamin D/calcium as a child
What is the treatment for osteomalacia (rickets)
Vitamin D supplements and dietary advice
What is osteoporosis?
A condition that causes diminished bone mass, low bone density
What are the symptoms for osteoporosis?
Back pain, reduced height, stooped posture, unexpected fractures
How do you diagnose and manage osteoporosis?
DEXA scan > measures bone density
Managed with exercise, Ca and Vit D supplements, bisphosphonates
What happens in fibrous dysplasia
Fibrous dysplasia = abnormal growth of fibrous tissues
chronic disorder, scar-like tissue grows in place of normal bone, weakening it over time
What is the presentation of fibrous dysplasia?
ground-glass appearance on radiographs
ALP is raised, but Ca and K ions normal
What is ALP?
Alkaline phosphatase
Enzyme found in osteoclasts
What is Paget’s Disease?
Unknown aetiology, causes unbalanced bone remodelling
shows areas of mixed lysis and sclerosis
Dental considerations of Paget’s Disease
- Bisphosphonates are a common Tx
- can get AV fistulas > cardiac failure
- hypercementosis of teeth
- bulging of maxilla
- risk of excessive bleeding and osteomyelitis
Calcitonin is released by the ____ when the ___ is ____
Thyroid gland, blood calcium levels are too high
What is primary hyperparathyroidism
parathyroid adenoma, causing excessive release of PTH:
hypercalcemia, bone pain, peptic ulcers, pancreatitis
What is secondary hyperparathyroidism?
a condition outside of the parathyroid gland causes parathyroid hyperplasia (chronically low vit D, kidney failure)
How can a clinician differentiate primary and secondary hyperparathyroidism?
Primary = high Ca serum levels
What is the aetiology of marfan’s syndrome?
Autosomal dominant, connective tissue disorder
What happens in Marfan’s syndrome?
connective tissue disorder causing hyper-flexible joints, lax ligaments, hernias
mitral valve prolapse, cardiac issues
What is Ehlers-Danlos Syndrome?
group of rare autosomal dominant disorders that impacts collagen formation
Signs and symptoms of Ehler-Danlos Syndrome?
Hyperflexible skin, bruising, loose joints, recurrent spontaneous dislocations, poor healing
Define osteoarthritis
Degeneration of the articular cartilage and proliferation of new bone
remodelling of joint contour
Where are you likely to find a patient presenting with osteoarthritis?
Load-bearing joints (knees, hips)
Tx for osteoarthritis
Analgesia, joint replacement, weight loss
What is rheumatoid arthritis
Systemic Auto-immune disease causing symmetrical, destructive inflammation joints
How does Rheumatoid arthritis affect the joints?
Causes inflammation of the Synovium (soft tissue inside/lining the joint space)
How do you diagnose Rheumatoid arthritis?
Stiffness of the hands/feet, worse in morning
ulnar deviation makes hands point outward
5 cardinal inflammatory signs in joints
+ve testing for rheumatoid factor
Management for Rheumatoid arthritis
NSAIDS
corticosteroids
DMARDS (Disease modifying anti-Rheumatic drugs)
Dental consideration of rheumatoid arthritis
in hands -> OHI
often associated with Sjorgen’s syndrome
Medications: risk of bleeding/MRONJ
What is ankylosing spondylitis
Form of chronic inflammatory arthritis, mostly in males, causes fusion of spinal vertebrae over time
Treatment for ankylosing spondylitis
Physiotherapy, exercise, NSAIDS
What is gout?
Form of chronic inflammatory arthritis
What is the mechanism of gout?
Chronically high urate levels (from breakdown of purines, meat and seafood) forms crystals of monosodium urate which are deposited into the joints
Clinical features of gout
-inflammatory arthritis
- inflammation of synovium membrane
- renal disease
- most common joints: joint on big toe, wrist, base of thumb
Causes of gout
High uric acid (from breaking down purines found in red meat, seafood)
high BP
diabetes, obesity
Tx for Gout
NSAIDs, Allopurinol
