Musculoskeletal (Week 11) Flashcards
Define compartment syndrome
Elevated interstitial pressure in a closed fascial compartment = microvascular compromise
What is the equation for calculating local blood flow (LBF)
(Pa - Pv)/R
List 3 end stage limb changes
- Stiff fibrotic muscle
- Limb clawing
- Loss of function
Name the four compartments of the leg
- Anterior
- Lateral
- Superficial posterior
- Deep posterior
What is the link between compartment syndrome and renal impairment?
Myoglobin/muscle breakdown products can damage kidneys
What genetic predisposition is related to rheumatoid arthritis?
HLA-DR4
Name three deformities seen in rheumatoid arthritis
- Swan neck
- Boutonniere
- Ulnar deviation
What is rheumatoid factor?
IgM antibody against Fc portion of IgG antibody
Name the three convention DMARDs
Methotrexate
Sulfasalazine
Hydroxychloroquine
What percentage of bone is organic matrix?
40%
What feature of cortical bone makes it resistant to bending and torsion?
Higher Young’s modulus
What are the four steps of indirect bone healing?
- Fracture haematoma
- Soft callus
- Hard callus
- Remodelling
Which bone in the hand is susceptible to necrosis and why?
Proximal pole of scaphoid due to retrograde blood supply
What type of bone is always affected first in AVN?
Spongy bone
What is the Crescent sign in AVN?
Subchondral radiolucency preceding subchondral collapse
Name the 5 most common primary tumours leading to bone metastasise?
Breast Prostate Thyroid (follicular) Renal Bronchi
What is Paget’s disease?
Excessive bone turnover leading to weak bones
What specific chromosome translocation is seen in Ewing’s sarcoma?
11:22 translocation
What is a comminuted fracture?
Fractures at lots of different sites on a bone
Name the 4 radiographic features of osteoarthritis
- Joint space loss
- Subchondral cysts
- Subchondral sclerosis
- Osteophytes
Name three risk factors for gout
Age
Male gender
Obesity
What is the difference between reactive and septic arthritis?
In septic, bacteria can be aspirated from the joint but it cannot in reactive arthritis
What gene is strongly associated with reactive arthritis?
HLA-B27
What is vasculitis?
AI condition causing blood vessel inflammation
What vessels does giant cell arteritis affect?
Aorta and major branches
What are the 3 main categories for causes of chronic back pain?
Mechanical
Systemic
Referred
What is spinal stenosis?
Anatomical narrowing of spinal canal
In compression fractures, where does pain classically radiate to?
Belt around the chest/abdomen
Name three red flags of chronic back pain
After trauma
New onset <16 or >50
Previous cancer
What gene is associated with Axial Spondyloarthritis?
HLA-B27
Name three extra-articular effects of axial spondyloarthritis
Uveitis
Psoriasis
IBD
Name the three types of ANCA associated vasculitis
Microscopic polyangitis
Granulomatosis with polyangitis
Eosinophilic granulomatosis with polyangitis
