Diseases of MSK Flashcards
What is ‘soft tissue’?
Non-epithelial extra skeletal structures exclusive of supportive tissue of organs and lymphoid/haematopoietic tissue
Name a benign tumour arising from;
a) fat tissue
b) fibrous tissue
c) smooth muscle
d) blood vessel
e) lymphatics
f) peripheral nerves
a) lipoma
b) fibroma
c) leiomyoma
d) haemangioma
e) lymphangioma
f) neuroma
Is lymph node involvement common in sarcomas?
No - tend to spread via blood
What genetic condition predisposes you to tumours growing along your nerves (i.e. neurofibromas)?
Neurofibromatosis Type 1
What are the 4 main syndromes associated with soft tissue tumours? What type of tumours do each of them cause?
1) Neurofibromatosis Type 1 –> neurofibromas
2) Gardner syndrome –> fibromatosis
3) Carney syndrome –> myxoma, melanotic schwannoma
4) Turner syndrome (monosomy X) –> cystic hygroma
What is the most common symptom of NF1?
The most common symptom of NF1 is the appearance of painless, coffee-coloured patches on the skin, called café au lait spots.
Are the tumours of NF1 typically malignant or benign?
Tumours usually benign but may cause a range of symptoms
What is fibromatosis?
A condition where fibrous overgrowths of dermal and subcutaneous connective tissue develop tumours called fibromas.
What is familial adenomatous polyposis (FAP)?
A genetic conditions characterised by multiple colorectal polyps
What is Gardner syndrome? What type of cancer does it predispose you to?
A form of familial adenomatous polyposis (FAP).
High risk of developing colorectal cancer at early age.
How can Gardner syndrome manifest?
May manifest as aggressive fibromatosis of the retroperitoneum
What 2 types of tumours does Carney syndrome predispose you to?
1) Myxoma (spotty skin pigmentation)
2) Melanotic schwannoma (a rare form of pigmented neural tumour)
What is Turner syndrome?
Genetic condition in which a female is partially or completely missing an X chromosome
What type of tumour does Turner syndrome predispose you to?
Cystic hygroma
What is a cystic hygroma?
Fluid-filled sac resulting from blockage in lymphatic system (most commonly located in neck or head area)
Diagnosis of soft tissue tumours?
o Ultrasound guided core biopsy
o Wide excision
o Cytogenetics; culture of fresh tissue and karyotypic analysis
o Molecular genetics; FISH and PCR and RT-PCR
2 types of benign bone tumours?
Osteomas and osteoblastomas
Name of a benign cartilage tumour?
Chondroma
Name of a malignant bone tumour?
Osteosarcoma
Typical age group of osteosarcomas?
Young
Commonest site of osteosarcomas?
Around the knee (60%)
Name of a malignant cartilage tumour?
Chondrosarcoma
What is Ewing’s sarcoma?
A very rare type of cancerous tumour that grows in your bones or the soft tissue around your bones
What is a Giant cell tumour?
A rare, aggressive non-cancerous tumour that usually develops near a joint at the end of the bone.
What are the 5 main types of tumour that metastasise to bone?
- Thyroid
- Breast
- Prostate
- Kidney
- Lung
Typical gender affected by SLE?
Female
Cutaneous symptoms of SLE?
Butterfly rash is typical affecting the bridge of nose and the cheeks
Cardiac symptoms of SLE?
cardiomegaly, endocarditis
CNS symptoms of SLE?
important cause for morbidity and mortality –> convulsions, hemiplegia
Renal symptoms of SLE?
45% of patients develop nephrotic syndrome/glomerulonephritis
What is systemic sclerosis?
Rare chronic disease of unknown cause characterised by diffuse fibrosis and vascular abnormalities in the skin, joints and internal organs
Pathogenesis of systemic sclerosis?
Complex and poorly understood but vessel damage, inflammatory response and cytokines
There is a limited form of systemic sclerosis. What is this called?
CREST syndrome
What characterises crest syndrome?
Limited cutaneous involvement + oesophageal involvement and SI malabsorption;
Calcinosis Raynaud's phenomenon Esophageal dysfunction Sclerodactyly Telangiectasia
What is calcinosis?
Calcinosis is the formation of calcium deposits in any soft tissue.
What is sclerodactyly?
A hardening of the skin of the hand that causes the fingers to curl inward and take on a claw-like shape.
What is telangiectasia?
A condition in which widened venules cause threadlike red lines or patterns on the skin
What is polymyalgia rheumatica?
An inflammatory disorder that causes widespread aching, stiffness, pain in the muscles of neck, limb girdles and upper limbs and flu-like symptoms.
What other disease is polymyalgia rheumatica associated with?
What are the symptoms of this?
Associated with giant cell arteritis; affects occipital or facial arteries
o Pyrexia, headache and severe scalp pain
Define myopathy
Muscle disease unrelated to any disorder of innervation or neuromuscular junction
Define myositis
Muscle fibres and overlying skin are inflamed and damaged resulting in muscle weakness
What is malignant hyperthermia? Symptoms?
A type of severe reaction that occurs in response to particular medications used during general anaesthesia;
o Fast RISE in body temperature (to 105-degree F or higher) and severe muscle contraction when the affected person gets general anaesthesia o Muscle rigidity o High fever o Fast heart rate o Dark brown urine o Bleeding
What is rhabdomyolysis?
Destruction of skeletal muscle and release of muscle fibre content into blood.
How does rhabdomyolysis cause myoglobinuria?
- Myoglobin is released into the blood stream from muscle
* Filtered through the kidney and enters urine –> myoglobinuria (brown urine)
Presentation of myoglobinuria?
Brown urine
Rhabdomyolysis is not always a disease but can be a result of other causes.
Give some examples of some other causes;
o Trauma, crush injuries o Drugs; cocaine, amphetamine o Extreme temperature o Severe exertion-marathon running o Lengthy surgery o Severe dehydration o Important complication- acute renal failure
What is arthritides?
Inflammation of a join causing pain and stiffness
Not a single disease but seen in 100s of diseases
Symptoms of acute arthritides?
pain, heat, redness & swelling
What are the 2 commonest types of chronic arthritides?
1) osteoarthritis
2) rheumatoid arthritis
What is the commonest type of joint disease?
Osteoarthritis?
What characterises osteoarthritis?
- Progressive erosion of articular cartilage
* Results in the formation of bony spurs and cysts at the margins of joints
What systemic diseases can often underly osteoarthritis?
diabetes and marked obesity
Common place of osteoarthritis in men vs women?
Women - knees and hands
Men - hip
Pathogenesis of OA? What cell is implicated?
CHONDROCYTES
1) Chondrocytes produce interleukin-1 which initiates matrix breakdown
2) Prostaglandin derivatives induces the release of lytic enzymes which prevents matrix synthesis
What are Herberden’s nodes?
Heberden’s nodes are a symptom of osteoarthritis.
The lumps grow on the joint CLOSEST TO THE TIP of your finger (DIP joint)
What are bouchard’s nodes?
Symptom of osteoarthritis.
Lumps grow on MIDDLE JOINT of finger (PIPJ)
What is rheumatoid arthritis?
Chronic systemic disorder principally affecting the joints. Producing a non-suppurative proliferative synovitis causing destruction of articular cartilage and ankylosis of joints.
Define ankylosis
abnormal stiffening and immobility of a joint due to fusion of the bones.
Clinical presentation of rheumatoid arthritis?
o Malaise, fatigue and generalised musculoskeletal pain to start off
o Involved joints are swollen, warm, painful and stiff in the morning or after activity.
o Slow or rapid disease course and fluctuates over 4-5 years
o Small joints of the hands and feet are frequently affected-ending in a deformed joint
What gene is inherited susceptibility to rheumatoid arthritis (RA) associated with?
DRB1 genes encoding the human leukocyte antigen (HLA)-DR4 and HLA-DR1 molecules
What are the mediators of joint damage in RA?
Cytokines; IL-1/6 and TNF-alpha/beta
What is the criteria needed for RA diagnosis?
NEED 4; o 1) Morning stiffness o 2) Arthritis in 3 or more joint areas o 3) Arthritis of hand joints o 4) Symmetric arthritis o 5) Rheumatoid nodules o 6) Serum Rheumatoid factor
Autoimmune diagnostic test for RA?
- Rheumatoid factor (indicative but not diagnostic)
- Anti-CCP (ACPA)
Also analysis of synovial fluid to confirm the presence of neutrophils & inflammatory picture
What is the most common cutaneous manifestation of RA?
Rheumatoid nodules
What 4 diseases are defined as sero-negative arthritides (lack rheumatoid factor)?
- 1) Ankylosing spondylitis
- 2) Reiter’s syndrome
- 3) Psoriatic arthritis
- 4) Enteropathic arthritis
What is gout?
End point of a group of disorders producing hyperuricaemia
Clinical features of gout?
o Acute arthritis (transient attacks)
o Chronic arthritis
o Tophi in various sites
o Gouty nephropathy
What causes transient gout attacks?
Crystallisation of urates within and about joints, leading to chronic gouty arthritis and deposition of masses of urates in joints and other sites (tophi)
What is pyogenic osteomyelitis? What organism is mostly likely?
Inflammation of bone caused by an infecting organism.
S. aureus is most common
What is infective arthritis? Presentation?
Joint infection;
• Acutely painful and swollen joints with restricted movements
• Fever, leucocytosis and elevated ESR
Predisposing factors to infective arthritis?
trauma, IV drug abuse, debilitating illness
Clinical features of osteoporosis?
o Vertebral factures
o Kyphosis
o Scoliosis
2ary causes of osteoporosis?
o Endocrine disorders; Hyperparathyroidism, Type1 diabetes
o Neoplasia; Multiple myeloma
o Malnutrition
What infection is Paget’s disease of bone caused by?
Paramyxovirus infection
What is Paget’s disease of bone?
o Initial osteolytic stage o Predominant osteoblastic activity o Burnt out osteosclerotic stage o Net effect --> gain in bone mass o Newly formed bone is disordered and architecturally unsound
What can Paget’s disease of bone progress to?
o Tumours; Benign & Malignant
o Giant cell tumour; benign tumour
o Malignant; Osteosarcoma, chondrosarcoma, malignant fibrous histiocytoma
What is osteomalacia?
Defects in matrix mineralisation related to lack of vitamin D
Leads to decreased bone density (osteopenia) but skeletal deformities are not seen
How does hyperparathyroidism affect calcium?
o Increases bone resorption and calcium mobilisation from the skeleton
o Increases renal tubular reabsorption and retention of calcium
HYPERCALCAEMIA
What bone condition can hyperparathyroidism lead to?
Osteitis fibrosa cystica; loss of bone mineral with osteoporosis
What is renal osteodystrophy?
Skeletal changes of chronic renal disease; o Increased osteoclastic bone resorption o Delayed matrix mineralization o Osteosclerosis o Growth retardation o Osteoporosis
