MSK - Knee Examination Flashcards
VIVA
Please list some causes of a knee effusion
Trauma (e.g. ligamentous, osseous and meniscal injuries)
Osteoarthritis
Inflammatory arthritis (e.g. RA, post-streptococcal, reactive, rheumatic fever, IBD-related)
Septic arthritis
Malignancy
Gout/pseudogout
Varus vs valgus force
VIVA
The ‘unhappy triad’ also known as a ‘blown knee’ refers to which three injuries?
Rupture of the medial collateral ligament
Damage to the medial meniscus
Rupture of the anterior cruciate ligament
VIVA
A patient presents with a red, hot and swollen knee, what are your differentials?
Septic arthritis
Gout
Pseudogout
Inflammatory arthritis
Haemarthrosis
VIVA
Anterior lag on the anterior drawer test would indicate which pathology?
Anterior cruciate ligament laxity
This can be damaged by hyperextension of the knee joint
VIVA
What is a bursa and how does a bursitis develop?
A bursa is a fluid-filled sac that reduces friction between bone and soft tissue. It may be come inflamed due to infectious or non-infectious causes and this is termed bursitis.
The common types in the knee include:
Prepatellar bursitis: the prepatellar bursa becomes inflamed when there is increased friction between the skin and patella. This is sometimes referred to a ‘housemaid’s knee’.
Infrapatellar bursitis: friction between the skin and tibia can also lead to inflammation of the infrapatellar bursae. This is sometimes called ‘clergyman’s knee’.
What are the classical features of osteoarthritis on an X-ray?
LOSS
– Loss of joint space
– Osteophytes
– Subchondral sclerosis
– Subchondral bone cysts
What are the possible complications of joint replacement?
– Wound infection
– Prosthetic joint infection
– Venous thromboembolism
– Nerve, ligament or vascular damage
– Prosthesis malfunction
– Bleeding/haematoma
– Periprosthetic fracture
– Joint dislocation
What is capsaicin? How does it work? What is a common adverse effect?
Capsaicin is a component of chili peppers. It is thought to deplete neuropeptide substance P, which has been implicated in the pathogenesis of arthritis-related inflammation and pain. Its common adverse effect is transient burning at the site of application.
What are the classical features of gout on an X-ray?
Soft tissue swelling around a single joint
– Erosions
– Sclerosis
– Periarticular tophi (punched out lesions in bone)
NB: NO loss of joint space
What is pseudogout?
Abnormal deposition of calcium pyrophosphate dihydrate crystals in joints. Cause unknown but may be related to breakdown of ATP.
What are the findings of gout and pseudogout on polarising microscopy?
Gout = negatively-birefringent needle shaped crystals (Negative Needles)
Pseudogout = positively-birefringent rhomboid shaped crystals
What are the classical features of rheumatoid arthritis on a radiograph?
Classic features of rheumatoid arthritis on radiograph:
– Loss of joint space
– Soft tissue swelling
– Periarticular osteopenia
– Marginal erosions
Which HLA genes are associated with inherited susceptibility to rheumatoid arthritis?
DRB1 genes encoding the HLA-DR4 and HLA-DR1 molecules
Which complications may be related to Paget’s disease?
– Secondary osteosarcoma
– Nerve compression
– Kidney stones
– Heart failure
– Osteoarthritis
What are Angioid streaks?
Breaks in a weakened Bruch’s membrane (innermost layer of the choroid of the eye). They can be seen on fundoscopy and may be caused by:
– Pseudoxanthoma elasticum
– Paget’s disease
– Sickle cell disease
– Ehlers–Danlos syndrome
– Idiopathic
What is the cause of Marfan syndrome?
Autosomal dominant FBN-1 gene mutation which transcribes Fibrillin-1, a major constituent of elastin in connective tissues.
What are the possible complications of Marfan’s syndrome?
Eyes: lens dislocation (50%), myopia
Weak thoracic aorta: aneurysms, dissection
Valves: aortic regurgitation, mitral prolapse/regurgitation
What conditions may cause joint hypermobility?
– Marfan syndrome
– Down’s syndrome (chromosomal disorder)
– Cleidocranial dysostosis (inherited bone development disorder)
– Ehlers-Danlos syndrome (inherited elasticity disorder)
– Morquio syndrome (inherited metabolic disorder)
Knee flexor muscles?