Diseases of MSK 1 Flashcards
The group of diseases causing pain, stiffness and inflammation of the MSK system
Arthritides
2 different types of arthritides
Acute and Chronic
2 different types of chronic arthritis
Osteoarthritis
Rheumatoid arthritis
Commoneste type of joint disease aka degenerative joint disease, Progressive erosion of articular cartilage.
Osteoarthritis
What forms at the margins of joints in osteoarthritis
Bony spurs and cysts
Underlying systemic diseases in OA
Diabetes
Obesity
Which joints are affected by OA in men and women?
Men-hip
Women- knees and hands
Pathogenesis of OA
Deterioration or loss of cartilage
Bone forms spurs and cysts
Results in pain and limitaiton of movements
Cells which form the cartilage around bone
Chondrocytes
How do chondrocytes contribute to OA
-Produce interleukin 1- initiates matrix breakdown. -Prostaglandin derivative induces the release of lytic enzymess- prevents matrix synthesis
Abnormal stresses in weight bearing joints
Primary OA
What joints are commonly affected in OA
Fingers, knees and cervical and lumbar spines
What forms in the fingers in primary OA
Herbeden’s or Bouchard’s nodes
Chronic systemic disorder-principally affecting the joints
Rheumatoid arthritis
Pathogenesis of RB
Production of a non suppurative proliferative synovitis-destruction of articular cartilage and ankylosis of joints
Who is more at risk of RA- emn or women?
Women
What happens to the synovium in RB
Polypoid fibrovascular thickening of the synovium, forms a pannus that invades into the articular cartilage- penetrates subchondral bone and cyst formation
Clinical features of RB
Malaise, fatigue and generalised MSK pain
Joints are swollen, warm, painful and stiff in the morning or after activity
Small joints of the hands and feet are frequently affected
Mutations in which genes predispose you to RA
HLA
DR4
DR1
Name 2 primary exogenous arthritogens
EBV
Borrelia
Describe the pathogenesis of RA
Autoimmune reaction within the synovial membranes- CD4 positive T cells.
Release of cytokines- IL1,6, TNF alpha and beta
Criteria for diagnosis
Morning stiffness Arthritis in 3 or more joint areas Arthritis of hand joints Symmetric arthritis Rheumatoid nodules Serum Rheumatoid factor Typical radiographic changes-narrowing of joint space, loss of articular cartilage
What 2 main things are required for the diagnosis of RB
Rheumatoid factor- present in most
Analysis of synovial fluid- presence of neutrophils
RA- other systems involvement
Skin- rheumatoid nodules
Lung, spleen, heart and other viscera
What do you call arthitis which lacks rheumatoid factor
Sero-negative arthritides
4 sero negative arthritides
Ankylosing spondylitis
Reiter’s syndrome
Psoriatic arthritis
Enteropathic arthritis
End point of a group of disorders producing hyperuricaemia- uric acid is the end product of purine metabolism
Gout
4 clinical features of gout
Acute arthritis
Chronic arthritis
Tophi in various sites
Gouty nephropathy
Pathogenesis of gout
Transient attacks of acute arthritis- crystallization of urates within and about joints, leading to chronic gouty arthritis and deposition of masses of urates in joints and other sites - tophi
deposition of masses of urates in joints and other sites
Tophi
Sytemic illness and marked pain over the affected region is typical of what condition?
Pyogenic (bacterial) osteomyelitis
What shows up on the X-ray for pyogenic osteomyelitis
Lytic focus of bone destruction surrounded by zone of sclerosis
3 mechanisms of cause of pyogenic osteomyelitis
Haematogenous
Contiguous
Direct implantation
Acutely painful and swollen joints with restricted movements, with fever, leucocytosis and elevated ESR
Infective arthritis
Common bacterial causes of infective arthritis
Staph, strep, gonococcus, mycobacteria
Predisposing conditions for infective arthritis
Trauma
IVDU
debilitating illness
What are the d2 types of osteoporosis
Primary or secondary
Primary osteoporosis risk factors
Age and postmenopausal
Increased porosity of the skeleton, reduction in bone mass, localised or entire skeleton
Osteoporosis
3 clinical features of osteoporosis
Vertebral fractures
Kyphosis
Scoliosis
3 causes of secondary osteoporosis
Endocrine disorders
neoplasm e.g. multiple myeloma
Malnutrition
2 examples of ednocrine disorders that predispose you to secondary osteoporosis
Hyperparathyroidism, Type 1 diabetes
Paget’s disease
Osteoclast dysfunction- matrix madness. Histological hallmark-mosaic pattern
Cause of paget’s disease
Paramyxovirus
Pathogeneisis of osteoclast dysfunction e.g. paget’s disease
Pred. osteoblastic activity- gain in bone mass. Newly formed bone is disordered and architecturally unsound
Who is most at risk of Paget’s disease
5th decade, males
What bones are most commonly affected by paget’s disease
Axial skeleton and proximal skeleton
Most common symptom of pagets
Pain
What type of fractures do you get in Paget’s disease?
Chalk stick type fractures
3 causes of paget’s disease
Giant cell tumour- benign
Malignant-osteosarcoma, chondrosarcoma, malignant fibrous histiocytoma
Defects in matrix mineralisation, related to lack of vit. D.
Ostomalacia
Decreased bone density
Osteopenia
Are skeletal deformities seen in osteomalacia?
No
Excessive secretion of parathyroid hormone
Hyperparathyroidism
